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Post Options Post Options   Quote sybersitizen Quote  Post ReplyReply Direct Link To This Post Posted: 08 May 2013 at 15:39
Originally posted by grispie grispie wrote:

... A57 or A77...

On paper, the video specs for the two cameras are identical. However, as you say, the downsampling processes must be different. It makes sense that a camera has to work harder to downsample more pixels in the same video time frame, so it's possible that the routine employed by Sony for 24mp sensors results in somewhat degraded output. None of this is proven to my satisfaction, but it seems logical.

Another possible difference is microphone quality. My A55's built-in mics are mediocre, and I was greatly surprised to discover that my much less expensive HX9V's built-in mics are far better. Who knows what differences might exist within the SLT line?
 



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Post Options Post Options   Quote windhorse Quote  Post ReplyReply Direct Link To This Post Posted: 11 March 2019 at 22:15
I would like to share my (unhappy) experience with the problem of focus breathing while recording a video interview with my A7RII in AF-C mode with the hope this may help others avoid falling in the same trap.

Bad news: it looks terrible

Good: it seems to be quite avoidable

So-so: it can be (somewhat) fixed using warp stabiliser in Adobe Premiere

Trying to figure out what causes this, I read here that the cause of the problem may be, according to Bender73, "at apertures smaller than f8 PDAF no longer works and contrast detect takes over, resulting in focus breathing. You get it also at all apertures if you force the focus point out of the PDAF zone."

I am not sure if this is right or not? But if it is, that would explain why I got focus breathing, since the face of the person who was being interviewed was in the top third of the frame (out of the PDAF zone, right?). The aperture was greater than f8 so that was not the reason.

Throughoout the interview the camera was focussing with face detection auto focus turned on and working (I thought at the time) very well, as I kept seeing the white box around the face coming and going during the filming - though no green focus confirmation box? It was only when I got home that I realized I had a problem.

Fortunately applying warp stabilizer effect in Premiere really helped. It did not entirely get rid of the problem but reduced it to such a minimal degree that the focus breathing is barely visible.

How do you avoid focus breathing?


Edited by windhorse - 13 March 2019 at 02:00
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Post Options Post Options   Quote sybersitizen Quote  Post ReplyReply Direct Link To This Post Posted: 11 March 2019 at 23:29
Focus breathing is a result of inherent lens design. It is not avoidable and it has nothing to do with AF.

Somebody somewhere is abusing the term ... and I think it's you. ;)

What you're describing is rapid focus hunting due to some inability to lock on. I don't have E-mount stuff, so I'll let others handle the troubleshooting.
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Post Options Post Options   Quote Photosopher Quote  Post ReplyReply Direct Link To This Post Posted: 12 March 2019 at 02:00
Nothing to do with a7RII, so you should consider removing that from the title. The camera doesn't deserve to be associated with the topic. It confuses the issue.

Originally posted by sybersitizen sybersitizen wrote:

Focus breathing is a result of inherent lens design. It is not avoidable and it has nothing to do with AF.


Absolutely correct.

Originally posted by sybersitizen sybersitizen wrote:

What you're describing is rapid focus hunting due to some inability to lock on.


Yes, the description is more akin to focus hunting.

Originally posted by windhorse windhorse wrote:

Trying to figure out what causes this, I read here that the cause of the problem may be, according to Bender73, "at apertures smaller than f8 PDAF no longer works and contrast detect takes over,...


Perhaps. Sounds true enough.

Originally posted by windhorse windhorse wrote:

resulting in focus breathing. You get it also at all apertures if you force the focus point out of the PDAF zone."


No. That's going too far. The result is not focus breathing. But it may make focus hunting more prevalent in lower lighting conditions, and with certain camera/lens combos. It's not a universal. The degree of focus hunting that arises is dependent upon compound factors. But it does sound like a problem with focus hunting, and not focus breathing.

Originally posted by windhorse windhorse wrote:

I am not sure if this is right or not?


Good to have an open mind. It's not completely wrong, but it's not completely right either.

Originally posted by windhorse windhorse wrote:

But if it is, that would explain why I got focus breathing, since the face of the person who was being interviewed was in the top third of the frame (out of the PDAF zone, right?).


Not focus breathing. Focus hunting.

Originally posted by windhorse windhorse wrote:

Throughoout the interview the camera was focussing with face detection auto focus turned on and working (I thought at the time) very well, as I kept seeing the white box around the face coming and going during the filming - though no green focus confirmation box?


Youtube is rife with poor examples of using face detection for talking head interviews. I've even seen many so called instructors using it for professional work. This is just flat out wrong. There is no reason for talking head interviews to use face detection, or any auto focus whatsoever. I'm still trying to figure out if Philip Bloom was mocking the trend, or actually expecting it to work in his Part 2 rambling video autofocus mega-test shown HERE.. I'd like to think a professional such as Philip is mocking the idea.

Just use manual focus. And if your subject is bouncing around like the man on Philips clip, you should cancel the shoot and call a doctor to check him out. Talking head videos don't bounce around like that.

Originally posted by windhorse windhorse wrote:

It was only when I got home that I realized I had a problem.


Manual focus for talking heads. No reason for AF, and risking AF hunting. I don't care how good the technology claims to be.

A professional would have tested this out many times before ever shooting an actual job. Be as professional as possible and don't test technology on client time. Check clips while on set, preferably with a larger external monitor.

Originally posted by windhorse windhorse wrote:

How do you avoid focus breathing?


Hunting... Not breathing. I dismantle focus hunting by using manual focus when appropriate. I'll consider using auto focus for sports and action, but I still might manually focus. Try it, you'll like the control and peace of mind.

Breathing is best overcome by testing lenses to discover when and where it arises. First, the Sony dedicated Cine lenses are designed to minimize focus breathing throughout the zoom range. If that expense is out of line, then consider the 18-105/4 G or the 24-70/2.8 GMaster. Both have minimal focus breathing through much (but not all) of their zoom range. The problem with those two lenses is that their manual focus rings are accelerated fly-by-wire, than thus very difficult to use for manual focus live video. Those are the only lenses I have experience with E-Mount focus breathing.

Sony A-Mount has some options that have little to no focus breathing. The 50/1.4 ZA and 24/2 ZA show little to no breathing. They have good linear manual focus rings too.

The Minolta 28-70/2.8 G is a beautiful cine lens with practically no focus breathing and a great manual focus ring and superior smooth internal zoom that's light to the touch. I use the Minolta as my dedicated A-Mount cine lens, actually having removed the AF gears to make it full time manual focus. The ZA 24-70/2.8 has terrible focus breathing by comparison.

The old Tamron 20-40/2.8 A-Mount lens is a brilliant little thing with absolutely no focus breathing.

The A-Mount lenses can be adapted to E-Mount, so you have some budget options with linear focus rings.

Edited by Photosopher - 12 March 2019 at 02:05
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Post Options Post Options   Quote windhorse Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 00:49
Thanks very much for the informative replies that have provided even more learning opportunities than I had hoped to get. That is much appreciated.

Now I realize that I not only did not know the cause of the problem I was encountering, or what to do about it, I also did not know the correct technical term to describe it. Now I do, thanks to everyone who pointed this out. Unfortunately I don't know how to change the heading of the thread, perhaps to "(Old) Fools Rush in Where Angels Fear to Tread!"

What I still do not completely understand is what triggers focus hunting in AF mode, when a subject is standing stationary facing the camera, and how to mitigate it. I also cannot understand how it can have nothing to do with the way the focusing system of the camera or the lens or the software works, since it is an AF ie automatic not a MF operater instigated movement, right?

Unless it has something to do with the movement of the subject? However in the case I encountered this problem the subject was stationary, facing the camera, and only occassionally moving their hands, and there was nothing else moving in the frame apart from a little wind in the grass?

In this scenario, why is it wrong to use face detection auto focus? One reason I can think of may be that it is not always right, but in my experience neither is manual or any other type of focusing, and mostly it does almost always deliver very accurate eyeball focus.

Would the way contrast detection auto focus works make focus hunting more likely than phase detect auto focusing. If so (here comes another dummmie question) how can I be sure which mode, contrast or phase detect, the camera is in at any one particular moment?

The advice about using manual focus is quite understandable and most likely useful for those who prefer manual focus. For me, using AF to find focus works better than my eyes working in low light at the same time as conducting an interview, despite the odd upsetting encounter with focus hunting.

Hoewever, given the useful feedback, I am thinking about reverting to focusing with AF then switching to MF that I have also tried before and found that it works well - until the subject moves out of focus.

I agree it would be better to have solved this before doing interviews in the field! The reason I did not was because in the practice interviews I did before doing the interviews the problem did not appear - perhaps because the light in the interview situation was lower, the straightness of the horizon in the background made the movement more obvious and the movement of the hands of the person in front of the camera was not identical to the movement in the practice session?

Yes, it would be better to have asked the person being interviewed to wait while I checked the recording before going home, living is learning.

By mentioning the A7RII in the heading of my post, I did not wish to cast any blame for the problem on this very fine camera. I just thought this would indicate the relevance of the post to the topic of the forum and help with problem-solving - just as I would indicate the model and operating system of a computer if I were to post in a computer forum about a problem I was encountering. Apologies to anybody who interpreted this as an attack on the camera.

There is no doubt the problem is the way I am using the camera. Fotunately this ought to be easy and and cheap to fix through sharing experiences, asking questions and learning, even if it enrages some.






Edited by windhorse - 13 March 2019 at 01:16
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Post Options Post Options   Quote Photosopher Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 01:41
Originally posted by windhorse windhorse wrote:

What I still do not completely understand is what triggers focus hunting in AF mode, when a subject is standing stationary facing the camera, and how to mitigate it.


As stated earlier, the components which contribute to focus hunting are not universal. Age of camera (the technology, the processor speed), brand and maximum fstop of lens (Tamron f4 vs Zeiss f1.4 vs adapted Canon f2.8), and available light (sunny day vs jail cell), will all play critical roles in the level of focus hunting.

Dyxum lens reviewers often list what camera a lens is tested upon, and the comments section often provides feedback for how a particular combination works together. If in doubt, ask the forum about a particular combination. Chances are someone here has used whatever you're interested in.

Originally posted by windhorse windhorse wrote:

I also cannot understand how it can have nothing to do with either the camera or the lens, since it is an AF ie automatic not a MF operater instigated movement, right?


Focus breathing is a characteristic of optical design. Example HERE.. It has nothing to do with focus hunting.

Focus hunting is a characteristic of the compound elements listed above. It has nothing to do with focus breathing. The term denotes how much a particular camera/lens/lighting combo can acquire a focus target. "Stickiness" denotes how well the combo can stick to the target without jumping to another object. "Tracking" denotes how well the combo can track objects moving towards or away.
Hunting, Tracking, Stickiness, and Breathing are independent.

Originally posted by windhorse windhorse wrote:

Unless it has something to do with the movement of the subject?


Not universal. A fast moving high contrast target in good light may be easier to track than a slow moving low contrast target in poor lighting. Not all face detection systems are equal. Not all lenses track the same. Not all cameras have equal AF processing power.

Originally posted by windhorse windhorse wrote:

In this scenario, why is it wrong to use face detection auto focus?


Because it didn't satisfy the results you hoped for.

Originally posted by windhorse windhorse wrote:

Would the way contrast detection auto focussing work make focus hunting more likely than phase detect auto focussing.


In most cases, probably. Not universal.

Originally posted by windhorse windhorse wrote:

If so (here comes another dummmie question) how can I be sure which mode, contrast or phase detect, the camera is in at any one particular moment?


Read your camera manual. View YouTube tutorials on your camera. Experiment.

Originally posted by windhorse windhorse wrote:

The advice about using manual focus is quite understandable and most likely useful for those who prefer manual focus.


I assure you, it's not necessarily preferred. It's just necessary. I'd love to just "think" my shots in focus. I'd love if the camera could always do the same. But neither I, nor it, can. Some work better than others.


Originally posted by windhorse windhorse wrote:

For me, using AF to find focus works better than my eyes working in low light at the same time as conducting an interview, despite the odd upsetting encounter with focus hunting.


Why are you shooting an interview in low light? It doesn't sound like it "works better" for you. Why are we having this talk if it works better for you?

Originally posted by windhorse windhorse wrote:

Hoewever, given the useful feedback, I am thinking about reverting to focussing with AF then switching to MF that I have also tried before and found that it works great - until the subject moves out of focus.


Why would the subject move out of focus? Are they sitting in a rocking chair? Swinging on a swing? Drop their pencil?

Look, sorry about the sarcasm. But seriously, can you point me to any quality talking head interview where the subject is poorly lit, and moving around enough to go out of focus? If this is a trend, then I'd like to see it for myself. If not, then stick with standard practice, and learn how to shoot an interview properly.

Originally posted by windhorse windhorse wrote:

I agree it would be better to have....


I hope you find the knowledge you desire with the tutorial link above. Good luck.
 



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Post Options Post Options   Quote stiuskr Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 01:44
Originally posted by windhorse windhorse wrote:

..Unfortunately I don't know how to change the heading of the thread, perhaps to "(Old) Fools Rush in Where Angels Fear to Tread!"...


I think we'ere past the point of editing the title and avoid confusion with the already posted replies, or maybe put it in parentheses (hunting) to clarify the topic but for future reference if you edit the original post you'll also see the title box (Subject:) there too if you want to edit the title
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Post Options Post Options   Quote sybersitizen Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 01:45
Originally posted by windhorse windhorse wrote:

What I still do not completely understand is what triggers focus hunting in AF mode, when a subject is standing stationary facing the camera, and how to mitigate it.

I hope someone can shed light on your particular scenario. Because AF doesn't work the same in all cameras, the answer should ideally come from someone with some deep knowledge about the A7RII.

I also cannot understand how it can have nothing to do with the way the focusing system of the camera or the lens or the software works, since it is an AF ie automatic not a MF operater instigated movement, right?

Focus hunting is very much about AF. Focus breathing is the thing that is independent of AF. Focus breathing is the rather strange name given to the condition wherein a lens changes its focal length* when the focus distance is changed. Most lenses exhibit noticeable breathing but some are designed to have very little or none. Even if the focus changes smoothly (no hunting) from one subject to another subject at a different distance, a lens that inherently breathes can still be observed to breathe during that change. This is not at all uncommon even in major motion pictures and television.

By mentioning the A7RII in the heading of my post, I did not wish to cast any blame for the problem on this very fine camera. I just thought this would indicate the relevance of the post to the topic of the forum and help with problem-solving - just as I would indicate the model and operating system of a computer if I were to post in a computer forum about a problem I was encountering.

I agree - the camera model might be a piece of relevant info.

There is no doubt the problem is the way I am using the camera.

I presume there are some cameras you could have used in the same way without anything weird happening; but I don't know enough about all the AF variations to expound on that.

* I suppose it would be more accurate to say the angle of view changes when the focus distance is changed because lots of simple prime lenses exhibit breathing.

Edited by sybersitizen - 13 March 2019 at 01:56
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Post Options Post Options   Quote windhorse Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 02:07
Thanks Stiuskr for the tip on how to change the title. I hope what I just did hasn't made this more confusing than it already is (at least to me) or needs to be.

Unknown to me when I posted this post, the problem has nothing to do with focus breathing. Also, I use prime lenses, so it has nothing to do with zoom lenses either.

Syber good to hear from you. As well as using the A7RII I am also trying to figure out how to do time lapse with that NEX6. The camera works perfectly but the thing behind the camera still has a way to go.
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Post Options Post Options   Quote windhorse Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 03:35
Photosopher, I usually film interviews as head shots with Zeiss Batis 85mm f/1.8 Lens in APS-C mode in quite low (but not very low) light, and while doing so I have hardly ever encountered the problem with focus hunting that I got when I switched to doing exactly the same with a Sony Sonnar T* FE 35mm f/2.8 ZA Lens in APS-C crop mode on my last outing (to get a medium shot instead of a close up). Could that change of lens account for part of the problem I encountered?

One major difference resulting from this change of angle was that the head of the subject moved from the center of the screen to the top third. Could that also be a reason why the AF worked less well and hunted more, though not continuosly - just enough to be extremely annoying when I realised what I had done!

On balance I would say I get more focus problems when manually focusing than I do with auto focusing and usually the win margin with AF is sufficiently greater than the lose margin that it does not bother me. I also find it much harder to manually focus a DSLR than I used to do with my old Crown Graphic though this perhaps has more to do with advancing age than advancing (or receding) camera technology. Maybe I should start using a dark cloth and loupe again or go back to the Graphic, as we are about the same vintage.

I did try manual focusing with a Zacuto viewfinder loupe but it worked for me about as well as tryig to focus a seagull through a submarine periscope and felt just as clunky (though realise others may have different experience). Not enough room in my gear suitcase for an extra monitor mounted on the camera like I see others use. Hence my preference for AF.

Looks like low light may be a contributing factor to the focus hunting, though in the case that disturbed me so much that I made this post the camera was set at about f4 asa800 s/s160 so the light level (just as the sun started to rise above the horizon) was not extremely low.

Working in a controlled studio environment would be easier - but perhaps not as much fun?

Edited by windhorse - 13 March 2019 at 03:43
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Post Options Post Options   Quote rosspa29 Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 08:26
Hi Windhorse
Manual focus with any of the A7 series cameras is easiest using focus magnification.
manual Focus using focus magnification will give precise focus.
You can move the area around to select the spot you need to focus on after the scene is magnified.
use enough light to increase your fstop to F8 should also compensate for movement of the interviewee's head. As mentioned above if you intend to conduct an interview with your subject seated there will be very little movement or need to refocus.
Regards Ross
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Post Options Post Options   Quote jkp1 Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 08:29
A remark to the reference to lens database by Photosopher....:
There are "no" info about lens quality related to video usage in the lens database, if, then only by coincidence somewhere hidden in text. (ie Focus breathing, aperture breathing, change in focus during zoom, estimates of T-values, af or aperture noise, things like that...)

Secondly, no matter if it is in low light or good light, my A7R3 do the same. Finding focus, but after a while it makes a quick front/back focus and back to focus. Really annoying. (That other camera brands do the same, fx panasonic, is giving no satisfaction)

This happens w kitlens, 24-105 and 70-200. Not all the time...

I use the AF-On button to tackle the problem. Finding focus by AF, then pressing the AF-On button to go to MF, keeps pressing the button.
(Or, if the situation cater for it, full manual focus.)

btw....wondering if changing any settings like:
- Phase detect area on/off
- AF track sensitivity
- Focus area
- Swt V/H AF Area
- If you are in M, Movie or any other modes
would do any magic ?


Edited by jkp1 - 13 March 2019 at 09:22
Unused stuff in stock: A700, 24-105, 28-135, FE28-70, Sony A7mk2, A100, beercan, 100-200, Sony 70-200f2.8
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Post Options Post Options   Quote jkp1 Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 08:41
btw. I often use AF with live interviews, well its often pretty necessary if you walk around with the cam on a monopod or handheld
Unused stuff in stock: A700, 24-105, 28-135, FE28-70, Sony A7mk2, A100, beercan, 100-200, Sony 70-200f2.8
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Post Options Post Options   Quote Photosopher Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2019 at 13:27
Originally posted by windhorse windhorse wrote:

...with Zeiss Batis 85mm f/1.8 Lens in APS-C mode in quite low (but not very low) light, and while doing so I have hardly ever encountered the problem


Originally posted by jkp1 jkp1 wrote:

...no matter if it is in low light or good light, my A7R3 do the same. Finding focus, but after a while it makes a quick front/back focus and back to focus. Really annoying.


That's the thing guys, "hardly ever" and "after a while" is not good enough. A near perfect three minute video clip is absolutely ruined with one single micro second focus blip. Not worth the risk using any type of AF during the recording. I honestly cannot fathom why anyone would risk continuous AF for a talking head interview.

I see some advantage for using AF for initial focus acquisition. But even then, manual confirmation is absolutely necessary. And the tools I use for doing so are plentiful with magnification, focus peaking, and sometimes with external 7 inch monitor with a good set of reader glasses on.

Originally posted by windhorse windhorse wrote:

...with focus hunting that I got when I switched to doing exactly the same with a Sony Sonnar T* FE 35mm f/2.8 ZA Lens in APS-C crop mode on my last outing (to get a medium shot instead of a close up). Could that change of lens account for part of the problem I encountered?


Good that you stated "account for part"... Yes, it's a compound problem. Depending upon lighting conditions (later you mention sun rising... is that backlighting?)... What was your aperture? E-Mount does much better AF with wide open aperture. Stopping down exponentially degrades AF performance, stickiness, accuracy... And what settings is your camera set for...? Responsive, Normal, or Locked On? It's a symphony, not a soloist.

Originally posted by windhorse windhorse wrote:

One major difference resulting from this change of angle was that the head of the subject moved from the center of the screen to the top third. Could that also be a reason why the AF worked less well and hunted more, though not continuosly - just enough to be extremely annoying when I realised what I had done!


Chasing the wrong dragon. What you really want to know is why the shot is out of focus... Not why the camera failed to focus it. The shot is out of focus because it was left to automation instead of manual expertise. Establish and inform the talent of their range of position. Let them know they can't just do or move any way they want. Then manual focus with an appropriate depth of field with appropriate lighting will accommodate any talent movement within the predefined range of acceptable movement.

It's much easier and more efficient to diagnose the mechanics of the shoot than it is to diagnose the mechanics of your camera. I can't say why for sure that your particular gear setup didn't accomplish the results you desired. But I can recommend a better shooting methodology that can achieve the results you desire with any gear setup.

Originally posted by windhorse windhorse wrote:

On balance I would say I get more focus problems when manually focusing than I do with auto focusing and usually the win margin with AF is sufficiently greater than the lose margin that it does not bother me.


On guitar, I have more success with the major scale than the minor scale. So I practice the minor scale more. It's amazing what practice can do. All professionals practice. How can one be professional otherwise?

Originally posted by windhorse windhorse wrote:

I also find it much harder to manually focus a DSLR than I used to do with my old Crown Graphic though this perhaps has more to do with advancing age than advancing (or receding) camera technology. Maybe I should start using a dark cloth and loupe again or go back to the Graphic, as we are about the same vintage.


Yes, but with an external monitor and eyeglass readers, focus peaking, focus magnifier, and the confidence that manual focus won't shift during the recording.

One thing very different between A-Mount and E-Mount cameras, both allow video shooting from stills mode.
And in stills mode, the A-Mount a99II will allow focusing at wide open aperture, even when using a smaller aperture. This makes for an easier magnified focus for initial acquisition (even if using AF). The lens won't close aperture until the video is engaged. E-Mount forces magnified focus at the actual aperture, therefor using magnifier at smaller apertures is more challenging because the EVF/LCD must gain up (with fuzzier view) and the smaller aperture depth of field makes it more difficult to differentiate critical focus.

The way to overcome this with E-Mount is to use a manual focus lens with preset aperture. Then you can focus wide open, lock it it, and then close aperture down (adjusting shutter speed appropriately) for the actual clip.

Or, use LA-EA3 or 4 adapter with A-Mount lens onto E-Mount camera, and use the A-Mount method previously described.

Originally posted by windhorse windhorse wrote:

I did try manual focusing with a Zacuto viewfinder loupe but it worked for me about as well as tryig to focus a seagull through a submarine periscope and felt just as clunky (though realise others may have different experience).


There are many different kinds of Zacuto finders. Are you talking about the Gratical, or just a loupe?

Originally posted by windhorse windhorse wrote:

Not enough room in my gear suitcase for an extra monitor mounted on the camera like I see others use. Hence my preference for AF.


My friend, that may be the most original excuse for preferring auto focus that I've ever heard. You have a small camera bag, so you prefer auto focus. I like that.

Originally posted by windhorse windhorse wrote:

Looks like low light may be a contributing factor to the focus hunting, though in the case that disturbed me so much that I made this post the camera was set at about f4 asa800 s/s160 so the light level (just as the sun started to rise above the horizon) was not extremely low.


Those settings are fairly decent levels. Was it backlit? That would contribute to poor AF.

Originally posted by windhorse windhorse wrote:

Working in a controlled studio environment would be easier - but perhaps not as much fun?


More fun to control out of studio shoots than be victimized by them.

External monitors are fairly cheap. Eyeglass readers are even cheaper. And yes, you can use them with your dark cloth no problem.

Edited by Photosopher - 13 March 2019 at 13:30
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Dyxum.com - Home of the alpha system photographer

In memory of Cameron Hill - brettania

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