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STF mode in Maxxum 7 recreated for DSLR's

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Printed Date: 15 February 2025 at 23:58


Topic: STF mode in Maxxum 7 recreated for DSLR's
Posted By: photoman
Subject: STF mode in Maxxum 7 recreated for DSLR's
Date Posted: 03 November 2009 at 04:02
I recently was pining over the 135mm STF lens because of the beautifully smooth bokeh that it can produce. It manages to smooth out the bokeh of an image much better than pretty much any lens ever made. For those of you who arent familiar with the amazing bokeh of this lens, here is a website that gives a good comparison:
http://www.artaphot.ch/lens-comparisons/17-bokeh-sal-135mm28-stf-cz-135mm18-and-af-70-200mm-apo-ssm - bokeh comparison

During my longing for this lens, I happened to remember that the Minolta Maxxum 7 had on it an STF emulator mode. This mode was supposed to give you a similar amazingly smooth bokeh on any lens that you owned. I'm pretty sure this was the only camera in the Minolta/Sony line ever to offer this feature. It was a great feature, but I dont think people really understood it well which is probably why it is no longer included in any cameras.

Well, I decided that I was going to make an attempt to manually recreate this feature on my a700. Here is how it worked on the Maxxum 7: The camera would take a sequence of 7 photos in rapid succession while varying the aperture for each shot. All exposures would be made on the exact same frame. The idea was to vary the aperture for each shot and then it would smooth over the circles from the aperture blades in the background.

I tried to recreate this by setting my camera up on a tripod and taking seven individual exposures of the same scene at varying apertures.   I then blended the images in photoshop so that each image composed 1/7th of the final exposure. Interestingly, it actually worked! The background is creamy and smooth smooth in the shots where I tried to recreate the STF mode.

I tested this on two lenses: minolta 50mm f/1.7 and an old Sigma 24mm f/2.8 macro

The aperture sequence for the 50mm was as follows:
f/1.7
f/2
f/2.2
f/2.5
f/2.8
f/3.2
f/3.5

Here are the results:

50mm STF mode recreated


50mm f/1.7


50mm f/2.5


50mm comparison




24mm STF mode recreated


24mm f/2.8


24mm f/4


24mm comparison



I like the results and can definitely notice a difference. I think the results would be even more interesting with lenses such as the 85mm f/1.4 or the CZ 135mm f/1.8.

Let me know what you think of these results.



Replies:
Posted By: zk-cessnaguy
Date Posted: 03 November 2009 at 04:31
Very interesting. Can you please explain your method for blending the images in Photoshop? I like the results you got with the 50/1.7 especially.


EDIT: just figured out how to do it. In CS4: File/Automate/Photomerge

very cool.

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There is nothing, absolutely nothing, half so much worth doing, as simply messing about in boats


Posted By: wallyb
Date Posted: 03 November 2009 at 04:39
That is VERY cool. I never noticed the STF function for the few months I tried out (and loved) a Maxxum 7. I'm going to have to give that a shot!


Posted By: skm.sa100
Date Posted: 03 November 2009 at 05:12
By 1/7th exposure, do you mean to say that you set the opacity to 1/7th and used overlay mode?

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More Dyxumer, less photographer.


Posted By: photoman
Date Posted: 03 November 2009 at 05:24
Here is how I did the blending. In one photoshop document, I created a layer for each of the seven images. The blending mode was set to "normal" for each layer. The blending was done by changing the opacity of the layers. The layers were ordered from "Layer 0" through "layer 6" with "layer 6" being the layer on top. Here are the opacity settings for each layer.

Layer          Opacity
Layer 6        14%
Layer 5        17%
Layer 4        20%
Layer 3        25%
Layer 2        33%
Layer 1        50%
Layer 0        100%


This results in each image making up 1/7th of the final image.   It doesn't matter what order you have the actual photos in as long as you arrange them so that the topmost photo has 14% opacity and the second topmost photo has 17% opacity... and so on.


Posted By: photoman
Date Posted: 03 November 2009 at 05:27
Originally posted by skm.sa100 skm.sa100 wrote:

By 1/7th exposure, do you mean to say that you set the opacity to 1/7th and used overlay mode?


I just tried what you suggested and it gave me ugly results with ugly contrast and ugly color.


Posted By: photoman
Date Posted: 03 November 2009 at 06:24
Open Letter to Sony: If anybody from Sony browses this forum, Why have you decided to not include an STF mode in your cameras? Please reinstate this mode in your cameras (firmware update). It was a wonderful feature that Minolta had and I see no reason to not include it.


Posted By: AlexKarasev
Date Posted: 03 November 2009 at 06:34
I also believe the STF mode goes well with Sony's philosophy of adding value to all lenses via the body (e.g. SSS)

I've written on this subject on this forum before. Even a single-shot STF should be possible, enabling it to be used handeld


Posted By: zk-cessnaguy
Date Posted: 03 November 2009 at 06:38
Just tried a quick and dirty attempt...


50/1.7 wide open


50/1.7 composited STF image.

I'm very impressed how it works, especially how the specular highlights top left are smoothed out.

Well done photoman!

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There is nothing, absolutely nothing, half so much worth doing, as simply messing about in boats


Posted By: wolfdagon
Date Posted: 03 November 2009 at 07:12
I think I tried the STF mode on my Maxxum 7 maybe once, but at the time I didn't really understand it. I now have the 135 STF for my A700, and i love it. It woud be great if they could implement the STF function in the A700 in firmware upgrade.

Great experiment photoman.


Posted By: albnok
Date Posted: 03 November 2009 at 08:11
It is easy to see how STF mode works on the Dynax 7 provided there is no film inside - open the film back and shoot while looking through the shutter.

I believe it shoots 7 frames at 1 stop intervals, thus:

F1.4 F2.0 F2.8 F4.0 F5.6 F8.0 F11

It does sound like it slows down considerably once it gets to the darker apertures, much darker than your 2-stop interval. Will record the sound to get an idea of the intervals.

Using the A900 I intentionally shot a closeup using my Minolta 50mm F1.4 Original, and the heptagonal aperture blades show very obviously. What is worse is that the heptagons maintain orientation as they stop down. Pictures are at home though. They didn't turn out as nice.

Probably I should try with 2/3rd stops instead so it's:

F1.4 F1.7 F2.2 F2.8 F3.5 F4.5 F5.6

I like the math you've done for the layer opacities - I'd been previously blending 2 pictures at 50% and guessing which of the pictures will take a higher precedence.

I still have a roll in my Dynax 7, waiting for when I can take it out with a tripod, and I'll do STF on night traffic. I know I've posted this somewhere but I can't find it.


Posted By: LetoAtreidesII
Date Posted: 03 November 2009 at 08:23
I can't see it working so well on night traffic since your subject isn't going to hold still while you shoot 7 frames...

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a200 | Sony 18-70 | Sony 24-105 | 50/1.7 | Beercan | 5400HS


Posted By: albnok
Date Posted: 03 November 2009 at 08:28
Oh, that is exactly the point, that the points of light are moving... think out of the box. ;)


Posted By: mhohner
Date Posted: 03 November 2009 at 09:32
Also note that with some lenses the focus shifts when stopping down. So the individual frames will not only have different bokeh and DOF, but also a different plane of focus. That's another advantage of a true STF lens.

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Sony/Minolta http://www.mhohner.de/sony-minolta/index.php" rel="nofollow - F.A.Q., bodies, lenses, flashes .


Posted By: dd001
Date Posted: 03 November 2009 at 09:53
Nice experiment, thanks a lot for sharing

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David - http://www.defoort.com/photos - My Gallery


Posted By: matthiaspaul
Date Posted: 03 November 2009 at 12:12
The Minolta Dynax 7 STF mode is based on an automatic multi-exposure of 7 shots with a constant exposure of 1/7th each, shifting both, aperture and speed at the same time.

The Minolta patents describing the background of this feature can be found in this thread:

http://www.mi-fo.de/forum/index.php?showtopic=22619 - http://www.mi-fo.de/forum/index.php?showtopic=22619 [de]

Since the DSLRs don't support multi-exposures, unfortunately, I would try to shot 7 exposures with constant (correct) exposure, shifting aperture and speed, and then combine them in postprocessing with a weight of 1/7th each, or shot with 1/7th and add the values of all 7 shots in postprocessing.

Greetings,

Matthias

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--

Minolta-Forum (MiFo) - German forum for the Minolta, Konica, Konica Minolta and Sony world of photography: http://www.mi-fo.de" rel="nofollow - http://www.mi-fo.de


Posted By: TallPaul
Date Posted: 03 November 2009 at 12:57
Actually DSLR's can do multiple exposures, its just ours that can't! I forget which bodies have it, but some definitely do, possibly the Fujifilm S5 or a Nikon body from memory.

Can't see why they can't do it in-camera with enough processing, would expect A850/900 to have the horsepower.

I must confess I have never tried the STF mode on my 7, but, you can guess what I will be doing later

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A900, 16-35/2.8Z, 70-200/2.8G, 85/1.4Z, 28-75/2.8, 50/1.7. Nex 6, 16-50mm & Rokkor MC/MD lenses.


Posted By: MarkSangenito
Date Posted: 03 November 2009 at 14:34
Actually DSLR's can do multiple exposures, its just ours that can't! I forget which bodies have it, but some definitely do, possibly the Fujifilm S5 or a Nikon body from memory.


count the canon 7d in there too, but I dont think that was intentional, haha.

Really well done photoman, seems to work well, and a pretty ingenious process.   


Posted By: photoman
Date Posted: 03 November 2009 at 14:36
Originally posted by mhohner mhohner wrote:

Also note that with some lenses the focus shifts when stopping down. So the individual frames will not only have different bokeh and DOF, but also a different plane of focus. That's another advantage of a true STF lens.


Upon close inspection of the individual images from the 50mm, I didnt notice any real shift in focus between the different images. The focus may shift on other lenses, but I don't know.

The sharpness of the in-focus parts of the final composite seem to be on par with that of the image shot at f/3.5. Of the individual images, the one shot at f/3.5 is definitely the sharpest.


Posted By: photoman
Date Posted: 03 November 2009 at 14:41
Also, feel free to share your results. I am interested to see how it works on the many different lenses of Sony/Minolta. Especially the high end large aperture lenses that I cannot afford to test myself.


Posted By: kefkafloyd
Date Posted: 03 November 2009 at 16:27
Originally posted by MarkSangenito MarkSangenito wrote:

Actually DSLR's can do multiple exposures, its just ours that can't! I forget which bodies have it, but some definitely do, possibly the Fujifilm S5 or a Nikon body from memory.


count the canon 7d in there too, but I dont think that was intentional, haha.

Really well done photoman, seems to work well, and a pretty ingenious process.   


The a500/550's auto HDR mode is multiple exposure.

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http://www.dvincentphotography.com - Daniel Vincent Aviation Photography


Posted By: wallyb
Date Posted: 03 November 2009 at 16:35
Originally posted by kefkafloyd kefkafloyd wrote:

Originally posted by MarkSangenito MarkSangenito wrote:

Actually DSLR's can do multiple exposures, its just ours that can't! I forget which bodies have it, but some definitely do, possibly the Fujifilm S5 or a Nikon body from memory.


count the canon 7d in there too, but I dont think that was intentional, haha.

Really well done photoman, seems to work well, and a pretty ingenious process.   


The a500/550's auto HDR mode is multiple exposure.
They mean multiple exposures on the same frame, not multiple consecutive exposures.


Posted By: skm.sa100
Date Posted: 03 November 2009 at 16:50
It was much simpler in the film days. Just don't move to the next and you'll get as many multiple exposures as you want. Especially where manual forwarding was required.
In DSLRs, the captured picture is written out to the card.
How will the camera know which image is to be superimposed on? Maybe the latest image? The user will probably have select a picture and tell the camera that multiple exposure is needed for that picture. The camera will end up taking a second picture and blend them together.
This is exactly what we do in an editor which supports layers. Maybe it's computationally expensive and hence isn't that widely supported.
Surely this is one of the most frequently requested features. There's gotta be a good explanation why it isn't supported widely.

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More Dyxumer, less photographer.


Posted By: beline
Date Posted: 03 November 2009 at 16:56
Do you know what the irony is here?

The CHDK firmware project. They have had multi exposure HDR for some time now, and they could implement this STF mode in a heartbeat. And they very-well MAY if they get wind of it.

And you know why thats ironic? Because a rebel project, unfunded, contributed to by janitors and web designers will implement a feature on a camera before Sony ever considers it. Or considers considering it...

Lame...

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http://www.coverthisphotography.com/" rel="nofollow">


Posted By: TallPaul
Date Posted: 03 November 2009 at 16:57
If my Minolta XD7 can do multi exposures and came from eBay for less than a Sony strap, you would have thought an A900 could

Sure you can do it on computer, but the camera is a tool, and I have lots of tools that do the same job, but sometimes I prefer to use a certain type of tool to another, its nice to have an option.

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A900, 16-35/2.8Z, 70-200/2.8G, 85/1.4Z, 28-75/2.8, 50/1.7. Nex 6, 16-50mm & Rokkor MC/MD lenses.


Posted By: beline
Date Posted: 03 November 2009 at 17:01
Oh, and in regards to implementation, You would have the camera take the shots, automatically varying the settings, buffering the frames and running a quick algorithm to calculate the final frame.

The process would actually smooth out random noise, and I would be happy if it was limited to JPG mode. However, limiting it to JPG wouldn't make sense, as doing the math on the compression algorithm would actually entail more overhead.

I don't know, just my 10cents.

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http://www.coverthisphotography.com/" rel="nofollow">


Posted By: Gabriel
Date Posted: 03 November 2009 at 17:01
Originally posted by skm.sa100 skm.sa100 wrote:

It was much simpler in the film days.

On my side, I find it easier in a DSLR. In the digital cameras featuring multi-exposure (I'm using a k20d myself, but several other ones also provide this feature), you can choose to either do an additive multi-exposure (in the same way as on film) or an averaging multi-exposure. While both modes have different uses, the possibility to let the camera handle the averaging itself ease the process.
If you want to combine 7 exposures (as an example), you can simply take 7 consecutive correctly exposed pictures. In the film days, you had to take 7 consecutive pictures exposed to 1/7th of a correct exposure. Of course you could do it, but automation doesn't hurt here.

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Pic a day http://tinyurl.com/2008-p-a-d - 2008 / http://tinyurl.com/2009-pad - 2009 / http://gabriel.mp3-tech.org/pics/galleries/2010_pic_a_day - 2010 galleries


Posted By: skm.sa100
Date Posted: 03 November 2009 at 17:05
Originally posted by photoman photoman wrote:

Originally posted by skm.sa100 skm.sa100 wrote:

By 1/7th exposure, do you mean to say that you set the opacity to 1/7th and used overlay mode?


I just tried what you suggested and it gave me ugly results with ugly contrast and ugly color.


Full points to you for trying!
I don't know what I was thinking. Yes, normal mode is the way to go, sorry!

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More Dyxumer, less photographer.


Posted By: Alanbrowne
Date Posted: 03 November 2009 at 17:09
I think you should re-do this with specular highlights in the BG and a scene that is more representative of what the STF lens is made for: portraits.

Having said that, doing portraits with 7 shots (or even 3 - 5) would be difficult no matter how fast the shutter is fired.

I also shudder to think how it could be done in the studio while maintaining lighting ratios and reciprocity - even the TTL flash system would likely not be able to keep up except at high ISO numbers.

Great effort though.

(The STF is still on my 2nd priority list - I have the 135 f/1.8 CZ which has admirable bokeh (not to mention a paper thin DOF at f/1.8)).


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I have discovered photography. Now I can kill myself. I have nothing else to learn.- Pablo Picasso


Posted By: Peek
Date Posted: 03 November 2009 at 17:13
Lol I didn't even know my dynax 7 had that feature!
Doh!
I still want an stf lense though.


Posted By: oldguy
Date Posted: 03 November 2009 at 17:21
I also didn't know the 7 did this. can't wait to try it.


Posted By: photoman
Date Posted: 03 November 2009 at 17:26
Originally posted by skm.sa100 skm.sa100 wrote:

Originally posted by photoman photoman wrote:

Originally posted by skm.sa100 skm.sa100 wrote:

By 1/7th exposure, do you mean to say that you set the opacity to 1/7th and used overlay mode?


I just tried what you suggested and it gave me ugly results with ugly contrast and ugly color.


Full points to you for trying!
I don't know what I was thinking. Yes, normal mode is the way to go, sorry!


Hey, it was worth giving a try. It is hard to understand how the different blending modes in photoshop actually work without trying them out. I tried different blending methods until I found out that the method I described seemed to give the best results. Nothing else I tried looked natural.

I was hoping for a more "automatic" method where I could use the same blending settings for all photos rather than manually selecting the opacities. However my search was unable to come up with anything better than manually varying the opacities.

Thanks for the idea though.


Posted By: photoman
Date Posted: 03 November 2009 at 17:56
at the request of Alanbrowne, i have redone this technique with a scene that has more specular highlights. Its not exactly a portrait scene, but the highlights are more intense than before.

50mm STF mode


50mm @ f/1.7


Posted By: Pekka L
Date Posted: 03 November 2009 at 20:07
Is there really something mechanical preventing this from happening in one go, if the masters presiding over incamera software so desire?

I mean, can the aperture lever not be moved during the exposure? I would imagine that must be possible. They could take out any further problems by rolling the shutter seven times during the exposure, to make sure every aperture position let's light through only for the exact time required.


Posted By: albnok
Date Posted: 03 November 2009 at 20:27
From the Dynax 7 in STF mode:



And here's one that shows the approximate diameters:



Posted By: Gabriel
Date Posted: 03 November 2009 at 20:59
Flektogon 35/2.4:


and Flektogon 35/2.4 in "STF mode":


("STF" combined in camera)

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Pic a day http://tinyurl.com/2008-p-a-d - 2008 / http://tinyurl.com/2009-pad - 2009 / http://gabriel.mp3-tech.org/pics/galleries/2010_pic_a_day - 2010 galleries


Posted By: beline
Date Posted: 03 November 2009 at 23:22
Originally posted by Pekka L Pekka L wrote:

Is there really something mechanical preventing this from happening in one go, if the masters presiding over incamera software so desire?

I mean, can the aperture lever not be moved during the exposure? I would imagine that must be possible. They could take out any further problems by rolling the shutter seven times during the exposure, to make sure every aperture position let's light through only for the exact time required.


Exactly, I really see no reason the aperture lever can not be moved during exposure, it would be interesting to see if the aperture could be "slide" from one f-stop to the next, with the camera doing the correct calculation to determine the shutter speed.

Or, like you suggest, rolling the shutter without dropping the mirror (which I actually don't think is possible, IIRC the mirror return is mechanicaly significant to the shutter resetting, I may be wrong though)...

However, I distinctly remember getting into the firmware debate some time ago that was decisively ended after one commenter pointed out the REALITY: No mater how simple the update may seem to us, they must go through the same process; concept, approval, development, debugging, submittal, approval, finalizing, distribution. And many little steps in between.

It sucks, but the costs are there, and it is pointless for Sony to implement niche updates that won't actually PAY for themselves.

Sure WE would love it, but how many consumers are going to know what STF means, or even want it? How many people do you think it would sway? not many...

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http://www.coverthisphotography.com/" rel="nofollow">


Posted By: N_Raged
Date Posted: 04 November 2009 at 04:39
This looks sweet. Time to find me a Fantasy card for my Maxxum 7000i, which does this very effect.


Originally posted by wolfdagon wolfdagon wrote:

It woud be great if they could implement the STF function in the A700 in firmware upgrade.
Can we stop dwelling on the A700?
It's discontinued, EOL, kaput. Sony is not going to add new features through firmware .
And it wouldn't make sense for Sony to include an STF mode in camera. Doing so would kill sales of the 135/2.8 STF lens itself.

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http://www.afxproductions.ca" rel="nofollow - afx productions

| A700 A55 7 7000i | Sigma 17-70/2.8-4.5 30/1.4 | Minolta 35-70/4 70-210/4 24/2.8 50/1.4 85/1.4G |


Posted By: wolfdagon
Date Posted: 04 November 2009 at 07:02
Originally posted by N_Raged N_Raged wrote:

Can we stop dwelling on the A700?
It's discontinued, EOL, kaput. Sony is not going to add new features through firmware .


I'm afraid that I will be dwelling on the A700 for at least a few years. I dont plan on upgrading anytime soon. I realize that it is discontinued, and that we will not be getting any more firmware upgrades (at least not from Sony). I'm just saying it would be nice.


Originally posted by N_Raged N_Raged wrote:

And it wouldn't make sense for Sony to include an STF mode in camera. Doing so would kill sales of the 135/2.8 STF lens itself.


I also agree with you on this. I was always surprised that Minolta included it in the Maxxum 7 for this reason.


Posted By: Lazer13
Date Posted: 04 November 2009 at 08:05
STF mode in the cameras would not kill the sales of the 135 STF lens.
The 135STF achieves the effect in one shot which makes it possible to use on moving targets. (Flowers outdoors, portraits etc..)
The STF mode would only be useful on tripod with still targets.

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http://lazer.mywire.org - Prime Challenge Galleries

A700 | Sig 10-20 | M 50 f1.7 | M 70-210 f4 | M 35-70 f4 | M 100 f2.8 Macro | Tok 300 f4


Posted By: LetoAtreidesII
Date Posted: 04 November 2009 at 08:07
If they implement "STF mode" by moving the aperture blades during a single exposure, then it would be useful handheld and with non-static targets.

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a200 | Sony 18-70 | Sony 24-105 | 50/1.7 | Beercan | 5400HS


Posted By: AlexKarasev
Date Posted: 04 November 2009 at 08:24
Originally posted by LetoAtreidesII LetoAtreidesII wrote:

If they implement "STF mode" by moving the aperture blades during a single exposure, then it would be useful handheld and with non-static targets.


... and with any lens (incl 135/1.8 :) and in AF mode as well, and last but not least the STF effect can be far more tunable/flexible as far as strength and character, compared to a fixed STF effect implemented in the 135 STF.

The only real limitation is for the in-camera STF mode is that the shutter speed must be no higher than the camera's X-sync shutter speed (1/250...1/300 sec on high-end shutters; slower on lower end cams) and likely even a little slower. While limiting, this would still be plenty useful considering this would be free with all of one's lenses as opposed to the 135STF, which is just one expensive manual focus lens. This limitation is due to the fact that the entire frame has to be exposed when the shutter blades are being moved during the exposure to create the STF effect. On speeds faster than X-sync, the frame is exposed sequentially as the gap between the shutter blades is traveling vertically, exposing corresponding areas of the frame.

The other limitation is the aperture has to be stopped down from wide open some (to allow the blades to move in both directions from the "average" aperture of the shot, for optimal STF effect). The reason this is not a real limitation is that the apodization element responsible for the STF effect on the 135/2.8T4.5STF lens is doing the exact same thing. Think of that apodization element (which gets darker towards the periphery and is clear in the middle) as the "motion blur" of those moving aperture blades, captured permanently in a piece of glass. That's where the T4.5 comes from. The advantage of the mechanical STF effect over a fixed element is the former is a lot more flexible and configurable. In particular it can be made more pronounced at smaller apertures compared to what's possible with the fixed apodization element that also has to serve wider apertures.

-- Alex Karasev


Posted By: AlexKarasev
Date Posted: 04 November 2009 at 08:38
Originally posted by wolfdagon wolfdagon wrote:

Originally posted by N_Raged N_Raged wrote:

And it wouldn't make sense for Sony to include an STF mode in camera. Doing so would kill sales of the 135/2.8 STF lens itself.


I also agree with you on this. I was always surprised that Minolta included it in the Maxxum 7 for this reason.


Actually I think it goes well with Minolta's (and now SONY's) philosophy of adding value to all lenses with camera body function. Think of in-body SSS vs. one that has to be built dedicated in each lens that is to have this function. It is pretty clear the advantage is to have a common function in a common place, strengthening the system overall. That's what drives the market share and profits and economies of scale for further R&D investment - not any individual instrument.

If SONY had added STF in-body plus sensor tilt (at least along the long axis) in-body (thus making every lens a tilt lens e.g. for DOF control in macro and product photography), they could further strengthen the system's appeal and reinforce the value they are already delivering with SSS being applicable to all lenses due to being implemented in the body.

-- Alex Karasev


Posted By: albnok
Date Posted: 04 November 2009 at 08:56
Did somebody say Zeiss 135mm F1.8 through the Dynax 7's STF?



Dare I say that from memory (since I did not shoot a reference F1.8 shot) that the DOF seems deeper due to the apodization on the OOF areas. This might also explain why the STF lens itself doesn't seem to have an easily shallow DOF at times. (While the Minolta 135mm F2.8 would scream bokeh in your face.)

Probably will revisit this subject with my A900 and 135mm F1.8 as I'm sure it would yield a shallower DOF.


Posted By: tuanle
Date Posted: 04 November 2009 at 08:56
I did use this idea on my A350 with the CZ 16-80

f 4.5-10



My conclusion: I should not use f > 7 :D


Posted By: Alanbrowne
Date Posted: 04 November 2009 at 23:23
Originally posted by N_Raged N_Raged wrote:

And it wouldn't make sense for Sony to include an STF mode in camera. Doing so would kill sales of the 135/2.8 STF lens itself.


Hardly. The STF is really in its element doing portraiture and there is no way to use the simulated STF mode for that unless the subject is embalmed waiting for the wake to end...

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I have discovered photography. Now I can kill myself. I have nothing else to learn.- Pablo Picasso


Posted By: Alanbrowne
Date Posted: 04 November 2009 at 23:26
Originally posted by photoman photoman wrote:

at the request of Alanbrowne, i have redone this technique with a scene that has more specular highlights.


I notice a couple places where the highlights exhibit a harsh ring in them (upper left in phots as well as upper right).

Not "STF" class, alas.


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I have discovered photography. Now I can kill myself. I have nothing else to learn.- Pablo Picasso


Posted By: matthiaspaul
Date Posted: 05 November 2009 at 11:27
Originally posted by beline beline wrote:

Originally posted by Pekka L Pekka L wrote:

Is there really something mechanical preventing this from happening in one go, if the masters presiding over incamera software so desire?

I mean, can the aperture lever not be moved during the exposure? I would imagine that must be possible. They could take out any further problems by rolling the shutter seven times during the exposure, to make sure every aperture position let's light through only for the exact time required.

Exactly, I really see no reason the aperture lever can not be moved during exposure, it would be interesting to see if the aperture could be "slide" from one f-stop to the next, with the camera doing the correct calculation to determine the shutter speed.

This is exactly how it should work, slowly close the aperture in a defined way during the exposure. It may not work for the shorter shutter speeds (the shortest emulated shutter speed the Dynax 7 STF mode can work with is 1/500s), but for the longer speeds (say 1/20s and longer) it should be possible to implement it this way. Actually, this is on our list of improvements for (Konica Minolta and) Sony for quite a while, but so far they didn't even bother to reintroduce the Dynax 7 STF mode at all. :-(

http://www.mi-fo.de/forum/index.php?showtopic=9250&view=findpost&p=130071 - http://www.mi-fo.de/forum/index.php?showtopic=9250&view=findpost&p=130071 [de]

Or, like you suggest, rolling the shutter without dropping the mirror (which I actually don't think is possible, IIRC the mirror return is mechanicaly significant to the shutter resetting, I may be wrong though)...

It may depend on the camera. In the Dynax 9, closing and reopening the aperture (DOF preview) requires to flip the mirror as well (but not to open the shutter). In cameras implementing "silent" DOF preview (since Dynax 7), the aperture is driven independent of the mirror and shutter mechanism, thereby also providing means to change the aperture in DOF preview.
Moving the mirror without opening the shutter is possible with other cameras as well, for example the MLU mode of the DSLR-A900 and DSLR-A850 works this way, when it resets back to normal after some idle time (unfortunately). You may be right about recocking the shutter without moving down the mirror being mechanically impossible, though. However, if so, it shouldn't be to hard to implement it in slightly different way so that both actions can be decoupled.

Regarding multi-exposures on DSLRs further up in this thread, of course, I meant Sony Alpha DSLRs, which don't provide this feature. Providing a buffer large enough for x frames for a generic multi-exposure might be a problem, but this would not be a problem for an STF mode unless combined with very long shutter speeds, because Sony won't need 7 buffers to combine the shots in camera. Instead, in perfect analogy to a film multi-exposure they could just fire the shutter 7 times in short succession (and as per STF program) without reading out the image, so the sensor will work as a charge buffer (that's what an imaging sensor is designed for, after all ;-). Since STF mode normally finishes within less than 2 seconds - at least in the range of short shutter speeds where the above approach to slowly close the aperture during a single exposure might not work - the dark current may not become much of an issue in STF mode, but if it does, the camera could utilize the dark frame subtraction method just as it does for normal long exposures.

Sure WE would love it, but how many consumers are going to know what STF means, or even want it? How many people do you think it would sway? not many...

But the combination of many such features makes up what can convince users to buy into the Sony system, whereas now, many such features are driving users into the Nikon system... Sony will just have to get their act together and significantly fine-tune their products to make them more attractive to users. In the past year, however, they have worked in the opposite direction, removing one useful feature after the other.

This is how I see Sony's offerings such as the DSLR-A900 right now: Raw cameras, capable, but still very basic in the feature department. A good hardware base to improve on, but still missing alot of detail-refinement and customization.

Greetings,

Matthias

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--

Minolta-Forum (MiFo) - German forum for the Minolta, Konica, Konica Minolta and Sony world of photography: http://www.mi-fo.de" rel="nofollow - http://www.mi-fo.de


Posted By: kiklop
Date Posted: 05 November 2009 at 13:36
Originally posted by matthiaspaul matthiaspaul wrote:


But the combination of many such features makes up what can convince users to buy into the Sony system, whereas now, many such features are driving users into the Nikon system... Sony just will have to get their act together and significantly fine-tune their products to make them more attractive to users. In the past year, however, they have worked in the opposite direction, removing one useful feature are the other.

This is how I see Sony's offerings such as the DSLR-A900 right now: Raw cameras, capable, but still very basic in the feature department. A good hardware base to improve on, but still missing alot of detail-refinement and customization.


And i second all of the above. Sony DSLR's Achilles heel isn't high image quality as many do imply but rather lack of features and options that modern DSLR cameras should provide.

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We may have http://www.dyxum.com/dforum/unawsered_forum_topics_date-range13.html - questions waiting for answers !


Posted By: kefkafloyd
Date Posted: 05 November 2009 at 14:27
Regarding multi-exposures on DSLRs further up in this thread, of course, I meant Sony Alpha DSLRs, which don't provide this feature. Providing a buffer large enough for x frames for a generic multi-exposure might be a problem, but this would not be a problem for an STF mode unless combined with very long shutter speeds, because Sony won't need 7 buffers to combine the shots in camera. Instead, in perfect analogy to a film multi-exposure they could just fire the shutter 7 times in short succession (and as per STF program) without reading out the image, so the sensor will work as a charge buffer (that's what an imaging sensor is designed for, after all ;-). Since STF mode normally finishes within less than 2 seconds - at least in the range of short shutter speeds where the above approach to slowly close the aperture during a single exposure might not work - the dark current may not become much of an issue in STF mode, but if it does, the camera could utilize the dark frame subtraction method just as it does for normal long exposures.


The a500/550's auto HDR is a multiexposure mode. I do not see it as unlikely that more multiexposure modes may come in the future.

Of course, people forget that it wasn't Sony that took the STF feature away from us - it was Minolta, because it was missing in our old KM 5D/7D too.

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http://www.dvincentphotography.com - Daniel Vincent Aviation Photography


Posted By: TallPaul
Date Posted: 05 November 2009 at 21:48
now kefkafloyd, we all know that Minolta are saints and Sony are evil, stop confusing the matter

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A900, 16-35/2.8Z, 70-200/2.8G, 85/1.4Z, 28-75/2.8, 50/1.7. Nex 6, 16-50mm & Rokkor MC/MD lenses.


Posted By: 6tyNine
Date Posted: 05 November 2009 at 22:47
this is brilliant. i'm gonna try this tonight.

edit: just remember reading about this a looong time ago. 2 years actually... seems like PP has come a long way since then.

http://www.dyxum.com/dforum/stf-mode-on-dynax-7_topic22064.html?KW=stf+mode - STF mode on Dynax 7

another related thread... http://www.dyxum.com/dforum/maxxum-7-stf-mode-experiments_topic26328_page1.html?KW=stf+mode - http://www.dyxum.com/dforum/maxxum-7-stf-mode-experiments_topic26328_page1.html?KW=stf+mode

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Sony α100, Sony 18-70mm f/3.5-5.6, Sony 75-300mm f/4.5-5.6


Posted By: AlexKarasev
Date Posted: 05 November 2009 at 23:32
... I distinctly remember getting into the firmware debate some time ago that was decisively ended after one commenter pointed out the REALITY: No mater how simple the update may seem to us, they must go through the same process; concept, approval, development, debugging, submittal, approval, finalizing, distribution. And many little steps in between.


:-) With the benefit of only having waited a few days I can smugly reply that apparently SONY is not above releasing a firmware update, even for a single and somewhat obscure (to average user of the cameras in question) feature, that nobody has even particularly complained about.

Originally posted by beline beline wrote:

It sucks, but the costs are there, and it is pointless for Sony to implement niche updates that won't actually PAY for themselves.


I think you are absolutely right on this one. It is clear SONY is willing to update firmware, but if it is for something WE want the burden is on us to unite and collectively tell SONY in an organized way that this is in fact what we want and we are prepared to be the ambassadors / marketers of the feature's benefit to make it worth their while. And if this past firmware update is any indication, SONY's threshold to justify a FW isn't even very high - they probably just want to hear it from a few warm bodies around the world with non-zero online reputations and experience/portfolios.

-- Alex


Posted By: beline
Date Posted: 06 November 2009 at 00:33
Alex. What are you talking about?

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http://www.coverthisphotography.com/" rel="nofollow">


Posted By: kefkafloyd
Date Posted: 06 November 2009 at 16:32
Originally posted by TallPaul TallPaul wrote:

now kefkafloyd, we all know that Minolta are saints and Sony are evil, stop confusing the matter


The KM 7D/5D also missed out on a lot of neat stuff that the Film 7 had, like the metering readout display, or the focus distance with DOF calculations on D lenses, etc.

These are things that IMO are less useful in the digital age because instant feedback destroys a lot of their need. They're toys, doodads.

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http://www.dvincentphotography.com - Daniel Vincent Aviation Photography


Posted By: sybersitizen
Date Posted: 06 November 2009 at 17:04
Originally posted by beline beline wrote:

Alex. What are you talking about?

He's talking about the recent firmware update being discussed in http://www.dyxum.com/dforum/topic54675.html - this other thread . I agree that it was an unnecessary update and I can't help wondering if Sony also implemented some other change(s) that they aren't mentioning.


Posted By: 6tyNine
Date Posted: 09 November 2009 at 06:23
went for a stroll tonight and decided to try it out. kinda odd. i think it'll take a bit more playing around with the opacities to make the final results best suited.

one of my greatest complaints about the stf is the thick DOF. i'm learning to see how this might be preferred which gives some structure to the bokeh as opposed to typical minolta cream.



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Sony α100, Sony 18-70mm f/3.5-5.6, Sony 75-300mm f/4.5-5.6


Posted By: parv
Date Posted: 09 November 2009 at 10:34
6tyNine, I would have stopped at f/4 as the star pattern had started to emerge at this point. Have you tried shots at 1/3 stop interval instead of 1 stop?

I will try with Minolta 80-200mm f/2.8 HS, which http://farm4.static.flickr.com/3447/3281125704_fb3cd3b7f3_o.jpg - lacks inherent good bokeh .


Posted By: 6tyNine
Date Posted: 09 November 2009 at 13:26
yea i was thinking about the stf range of f-stops.

that's quite strange, i always thought 80-200G had pretty good bokeh.

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Sony α100, Sony 18-70mm f/3.5-5.6, Sony 75-300mm f/4.5-5.6


Posted By: photoman
Date Posted: 09 November 2009 at 15:23
When using a very large aperture range like 6tyNine did, it seems to create a somewhat dreamy/soft focus look to the image. I think that in order to get a good STF look, one must use a somewhat smaller aperture range. I think the third image gives the best bokeh and still has a very shallow DOF.

These were shot on the Minolta 50mm f/1.7


STF on A700
Aperture range: f/1.7 - f/20
1-stop increments
8 images


Normal on A700
f/8



STF on A700
Aperture range: f/1.7 - f/3.5
1/3-stop increments
7 images



Normal on A700
f/1.7


Posted By: parv
Date Posted: 09 November 2009 at 16:20
Well, after a search I failed to come up with another contrary view about Minolta 80-200mm f/2.8 HS bokeh; perhaps the background was just brutal. Anybody wants to loan out 135mm STF for me to try?

I will need to find out some other place then. Any suggestions to avoid another brutality?


Posted By: zk-cessnaguy
Date Posted: 10 November 2009 at 02:32
Another attempt, this time using the following lenses:
Pentax Super Takumar 50/1.4; Pentax Super Takumar 85/1.9 and Pentax SMC Takumar 135/2.5

All lenses shot at wide open aperture then stopped down one click per shot until 7 images per lens were taken.

1. 50/1.4 at f1.4

Nasty bokeh! (and you can really see the yellowing colour cast...)

2. 50/1.5 STF simulation

Much better...

3. 85/1.9 at f1.9

Nice bokeh open... but we already knew that.

4. 85/1.9 STF simulation

Not much of an improvement, maybe a little bit smoother.

5. 135/2.5 at f2.5

Similar results to the 85/1.9.

6. 135/2.5 STF simulation

The smaller apertures used in the STF sim are starting to have an effect here.



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There is nothing, absolutely nothing, half so much worth doing, as simply messing about in boats


Posted By: Gabriel
Date Posted: 19 November 2009 at 21:32
Trial with a super-takumar (7 exposures blended):

standard:

stf:


It is indeed a huge improvement.

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Pic a day http://tinyurl.com/2008-p-a-d - 2008 / http://tinyurl.com/2009-pad - 2009 / http://gabriel.mp3-tech.org/pics/galleries/2010_pic_a_day - 2010 galleries


Posted By: Joe Appleby
Date Posted: 20 November 2009 at 14:24
I guess I will give this a try this weekend. Maybe with the Zeiss 135 3.5 M42. Although I have to check whether the aperture still closes correctly.

A friend of mine, Nikon user, will try this probably tonight on his new 14-24 2.8.


Posted By: 6tyNine
Date Posted: 20 November 2009 at 14:54
Originally posted by Gabriel Gabriel wrote:

Trial with a super-takumar (7 exposures blended):

standard:

stf:


It is indeed a huge improvement.


um... how?

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Sony α100, Sony 18-70mm f/3.5-5.6, Sony 75-300mm f/4.5-5.6


Posted By: kefkafloyd
Date Posted: 20 November 2009 at 15:39
I'm guessing because there's less outlining going on in the upper left.

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http://www.dvincentphotography.com - Daniel Vincent Aviation Photography


Posted By: Gabriel
Date Posted: 20 November 2009 at 17:05


Bokeh is smoother in the STF version(and we lost the hexagonal aperture shape). To my own taste, it is better.

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Pic a day http://tinyurl.com/2008-p-a-d - 2008 / http://tinyurl.com/2009-pad - 2009 / http://gabriel.mp3-tech.org/pics/galleries/2010_pic_a_day - 2010 galleries


Posted By: tleeds
Date Posted: 09 February 2011 at 00:30
Old topic, but I figured I'd interject.

I've used the STF and done a couple of these photoshop versions.

The point everyone seems to be missing is that the STF lens great bokeh is just a side effect. The real star (and the reason the lens is so nice) is the STF part. Smooth Trans Focus <- They're referring to the transition from in-focus to out-of-focus. On most lenses, that transition is abrupt and well defined. The STF magically gets progressively sharper as you approach the focal plane and progressively blurrier as you leave it. This is why images taken with the STF seem to *jump*. Focus on the STF is a gradient instead of being a hard cutoff.

Some of the photoshop renders here exhibit that awesome STF transition, but others look like regular photos with slightly better bokeh.

The STF is always a strange beast to use. It works better for some shots than others. (A portrait with a far-off background is not a good use of the lens or technique)... but a portrait taken at an oblique angle with your subject close to the background is a wonderful use of the lens.


Posted By: dekie
Date Posted: 09 February 2011 at 05:08
Recreated the effect in Photoshop with two layers and a layer mask on the
f1.7 version of your picture.

Lens blur on the upper layer.

This method is usable on handheld pictures with moving objects.



Gr.


Posted By: photoman
Date Posted: 18 May 2011 at 22:18
I just got a Minolta 85mm f1.4 and was wanting to try this technique out on this lens. Here are the results. I experimented with different f-stop ranges and with using different numbers of photos in the composite. I believe that using at least 7 images while varying the aperture at 1/3 stop increments gives the best results (this is the 7 image f1.4-2.8 case).

here is the original at f1.4



and here are comparison of the different setups I tried. Using only 3 or 4 images in the STF composite, it is pretty easy to see the overlapping image circles in the out of focus areas. Its hard to see this in the small image (darn you flickr). So http://dl.dropbox.com/u/3146906/STF%20comparison.jpg" rel="nofollow - here is a download for the original. Unfortunately it wont be permanently available. The image is full resolution from my a700.




Originally posted by tleeds tleeds wrote:

Old topic, but I figured I'd interject.

I've used the STF and done a couple of these photoshop versions.

...The real star (and the reason the lens is so nice) is the STF part. Smooth Trans Focus <- They're referring to the transition from in-focus to out-of-focus. On most lenses, that transition is abrupt and well defined. The STF magically gets progressively sharper as you approach the focal plane and progressively blurrier as you leave it. This is why images taken with the STF seem to *jump*. Focus on the STF is a gradient instead of being a hard cutoff.


Since you've got the STF lens and done several of the photoshop STF images, could you show us any examples of this?


Originally posted by dekie dekie wrote:

Recreated the effect in Photoshop with two layers and a layer mask on the
f1.7 version of your picture.

Lens blur on the upper layer.

This method is usable on handheld pictures with moving objects.



What did you do to the masked layer? Did you apply a gaussian blur or lens blur filter in photoshop?

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A700, Sig 10-20, 17-70, 24 f2.8 400 f5.6 telemacro, Min 85 f1.4, 50 f1.7, 70-210, Cosina 100 macro,


Posted By: dekie
Date Posted: 25 May 2011 at 23:52

Posted by Photoman
What did you do to the masked layer? Did you apply a gaussian blur or lens blur filter in photoshop?


Lens Blur in PS gives a blur that looks more like a lens blur. You can simulate the number of diafragm blades, rounded diafragm blades and specular highlights.

With a good masking technique you can create STF-like images in pp.

Gr.


Posted By: dekie
Date Posted: 26 May 2011 at 00:05
Example of lens blur applied on a Sony R1 image

original



after lens blur in PS, and lightening the background




Posted By: PieterB
Date Posted: 27 May 2011 at 06:00
How much time did this cost you?

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Pieter
Sony A7mk3
Sony 24-105/f4


Posted By: dekie
Date Posted: 27 May 2011 at 06:14

PieterB
How much time did this cost you?


Much less time than shooting and stacking 6 pictures.

And with the refine edge tool in CS5 it is quite easy to create a mask
in a more complex picture. The sample used here is an easy one.

Gr.






Posted By: Photosopher
Date Posted: 27 May 2011 at 06:41
Originally posted by dekie dekie wrote:

Lens Blur in PS gives a blur that looks more like a lens blur.


While I get your point, and appreciate the example, I must respectfully disagree with your assessment for all situations.

Without addressing the oddness in the hand/mouth area of your sample, what works adequately enough for quick web shots does not always translate properly for large art or portfolio images worthy of lengthy closeup inspection. As with any Photo Shop blurring technique, the texture of the blurred area is nearly impossible to match to the texture of the non blurred area. Although this is not apparent in web shots, I find it is apparent in print work both published and private. And I certainly don't want to start filtering any more than I have to just to match granularity and noise between foreground and background. That makes it difficult to keep an entire series consistent.

My goal is to always shoot it the best possible, and then use PP only when necessary, if at all.



Posted By: dekie
Date Posted: 27 May 2011 at 13:30

by Photosopher
Without addressing the oddness in the hand/mouth area of your sample, what works adequately enough for quick web shots does not always translate properly for large art or portfolio images worthy of lengthy closeup inspection. As with any Photo Shop blurring technique, the texture of the blurred area is nearly impossible to match to the texture of the non blurred area.


This was a quick example, and somewhat overdone with the blurring, only to illustrate the possibility.

Starting from a picture with more dof and applied slightly used, the pp is barely or not visible.

Both techniques are not the same as the result of a real STF picture.

Changing the aperture often changes the focal length of the lens. And shooting a series of pictures to stack is only possible with static subjects.

And blur is by definition the absence of texture.







Posted By: Photosopher
Date Posted: 27 May 2011 at 14:05
Sure I understand, and don't want to downplay the technique, as it certainly is a viable one.

My experience has shown the PP background blur works well for shots that don't show the ground. But getting the transitional defocus necessary for shots showing the feet is much more challenging.



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