FAQ FAQ  Forum Search   Events   Register Register  Login Login

Topic ClosedMirror lenses!

Page  <1 1617181920 33>
Author
mariuszlo View Drop Down
Senior Member
Senior Member

Joined: 17 December 2007
Country: United States
Location: Jersey City
Status: Online
Posts: 3286
Direct Link To This Post Posted: 02 December 2021 at 14:43
I agree that this comparison is a bit pointless. I just wanted to justify my statement that I am not satisfied with the image quality of the Reflex 500. Now for the last comparison.
Reflex

Minolta 200
Sony a7R4, a6400. E, A and MD lenses.
 



Back to Top
XKAES View Drop Down
Senior Member
Senior Member

Joined: 24 September 2021
Country: United States
Location: Colorado
Status: Offline
Posts: 269
Direct Link To This Post Posted: 02 December 2021 at 14:57
Given the DOF seen in both, the f-stops were not the same -- again apple vs orange.
Back to Top
mariuszlo View Drop Down
Senior Member
Senior Member

Joined: 17 December 2007
Country: United States
Location: Jersey City
Status: Online
Posts: 3286
Direct Link To This Post Posted: 02 December 2021 at 15:15
F-stops are not everything. First of all, ISO is different.
But I was not able to get a sharp shot with Reflex at ISO100. I used remote control, but with AF the camera shook so much that the picture was blurry. On the other hand, with MF I couldn't get a better focus.
This additionally discourages me from using Reflex. It goes deep into the closet.
And it's not much cheaper than the Minolta 200/2.8
Sony a7R4, a6400. E, A and MD lenses.
Back to Top
Matt View Drop Down
Senior Member
Senior Member

Joined: 30 November 2005
Country: Netherlands
Location: Limburg
Status: Offline
Posts: 740
Direct Link To This Post Posted: 02 December 2021 at 15:36
One thing definitely to use with the 500 Reflex is EFCS as (due to the low weight), the 500 Reflex is very susceptible to shutter shock.

See here: https://www.flickr.com/groups/500mmf8reflex/discuss/72157632076839713/
Back to Top
XKAES View Drop Down
Senior Member
Senior Member

Joined: 24 September 2021
Country: United States
Location: Colorado
Status: Offline
Posts: 269
Direct Link To This Post Posted: 02 December 2021 at 15:56
Originally posted by mariuszlo mariuszlo wrote:

F-stops are not everything. First of all, ISO is different.


The f-stop will effect the resolution/clarity/sharpness -- as will "shutter shock", ISO and camera movement. The comparisons need to be at the same ISO, at the same f-stop, and on a tripod.

And instead of putting the Reflex in the attic, sell it to someone who appreciates it.

I have a Soligor 200mm f2.8 C/D and Tokina APO 80-200mm f2.8. I'll have to run some tests against my Spiratone (Tomioka) 500mm f8 CAT -- at ISO 100, at f-8, and on a tripod.
Back to Top
woodrim View Drop Down
Senior Member
Senior Member

Joined: 19 October 2009
Country: United States
Location: Charleston, SC
Status: Offline
Posts: 1975
Direct Link To This Post Posted: 02 December 2021 at 17:11
As someone else said, comparing a cat to a refractor is apples to oranges. Unlike telescopes, most terrestrial mirrors aren't very good at infinity, as odd as that sounds. I don't think there has ever been a debate about sharpness and bokeh when compared to a refractor, and especially with today's better lenses.

There may be more than two reasons a person will choose a mirror but I think the most common are size and weight, and just liking them. I fit into both categories. Okay, I'm weird. I do like the unique rendering aside from extreme donuts and I enjoy the challenge of using them.

If anyone knows better, you can correct me. I think the laws of refractor optics do not apply equally to mirrors. Depth of field is one of them. I think a mirror has more shallow depth when compared at the same focal length and aperture.

We are better off comparing mirrors to mirrors, which can be useful.    
Regards,

woodrim
 



Back to Top
XKAES View Drop Down
Senior Member
Senior Member

Joined: 24 September 2021
Country: United States
Location: Colorado
Status: Offline
Posts: 269
Direct Link To This Post Posted: 02 December 2021 at 17:52
Originally posted by woodrim woodrim wrote:

I think a mirror has more shallow depth when compared at the same focal length and aperture.   


Perhaps my simple test (above) will shed some light on your believe.

I encourage other to try it as well.

My A850 has mirror lock up to reduce vibration, but I'll be using a fast shutter speed anyway, on a tripod.
Back to Top
neilt3 View Drop Down
Senior Member
Senior Member

Joined: 13 September 2010
Country: United Kingdom
Location: Manchester.U.K
Status: Offline
Posts: 3206
Direct Link To This Post Posted: 02 December 2021 at 19:30
Originally posted by mariuszlo mariuszlo wrote:

F-stops are not everything. First of all, ISO is different.
But I was not able to get a sharp shot with Reflex at ISO100. I used remote control, but with AF the camera shook so much that the picture was blurry. On the other hand, with MF I couldn't get a better focus.
This additionally discourages me from using Reflex. It goes deep into the closet.
And it's not much cheaper than the Minolta 200/2.8



Have another look at your lens from the other end .
I'm on my second copy as the first one I bought was faulty .
There were oil type deposits on the primary mirror which reduced contrast and sharpness .
That could well be the issue with yours ?
See the below picture I took of it , you need to hold the lens right with soft lighting to see it .

oil on 500mm Reflex
by Neil , on Flickr
see my photostream on flickr;
http://www.flickr.com/photos/neilt3/
C & C welcome.
Back to Top
XKAES View Drop Down
Senior Member
Senior Member

Joined: 24 September 2021
Country: United States
Location: Colorado
Status: Offline
Posts: 269
Direct Link To This Post Posted: 02 December 2021 at 19:43
Could that be fungus? Where would the "oil" come from -- I mean besides Saudi Arabia.
Back to Top
Snegren View Drop Down
Senior Member
Senior Member

Joined: 11 November 2011
Country: Netherlands
Location: Zuid Holland
Status: Offline
Posts: 6238
Direct Link To This Post Posted: 02 December 2021 at 19:56
Any lens has a focussing helicoid that needs lubrication. Grease can deteriorate and run to places where it doesn't need to be.
“People demand freedom of speech as a compensation for the freedom of thought which they seldom use.” Søren Kierkegaard
My Flickr
Back to Top
XKAES View Drop Down
Senior Member
Senior Member

Joined: 24 September 2021
Country: United States
Location: Colorado
Status: Offline
Posts: 269
Direct Link To This Post Posted: 02 December 2021 at 21:04
I've seen oil leak and streak in lenses, but never splatter.
Back to Top
darosa View Drop Down
Emeritus group
Emeritus group

Joined: 23 March 2007
Country: Netherlands
Location: Old Zealand
Status: Offline
Posts: 13985
Direct Link To This Post Posted: 02 December 2021 at 21:16
Originally posted by XKAES XKAES wrote:

Could that be fungus? Where would the "oil" come from -- I mean besides Saudi Arabia.


Read this.
Back to Top
neilt3 View Drop Down
Senior Member
Senior Member

Joined: 13 September 2010
Country: United Kingdom
Location: Manchester.U.K
Status: Offline
Posts: 3206
Direct Link To This Post Posted: 03 December 2021 at 00:53
Originally posted by XKAES XKAES wrote:

Could that be fungus? Where would the "oil" come from -- I mean besides Saudi Arabia.


Kebab ? chip pan ? full English breakfast ?

Alternatively ;

It was only on the inner circumference of the mirror , it looks clear except when held to daylight at the right angle where it had a rainbow type sheen , typically as seen when oil is on water .

I've not seen fungi do that .

I suspect the lens had been in a car baking in the sun and drawn out the oils in the grease , put on a camera , still hot , and when the AF fired up sprayed off the oil .
Only the inner edge of the mirror around the hole in the centre was effected , which would be consistent with it being sprayed/splattered forward .
If it was a fungus , I would expect a more random and further reaching dispersal on the mirror .

It was a fluid type deposit that I cleaned off with a degreasing agent .
It smeared when I touched it , but cleaned up easily .



Originally posted by XKAES XKAES wrote:

I've seen oil leak and streak in lenses, but never splatter.


You live and learn .
see my photostream on flickr;
http://www.flickr.com/photos/neilt3/
C & C welcome.
Back to Top
keith_h View Drop Down
Senior Member
Senior Member

Joined: 22 May 2006
Country: Australia
Location: Australia
Status: Offline
Posts: 3132
Direct Link To This Post Posted: 03 December 2021 at 02:01
I performed some tests with my AF500 and satisfied myself its sharp enough when used properly and with potentially excellent bokeh. The images are elsewhere in this post.

I'm doubting its going to be terribly useful for sports photography, but it seems if used according to its strengths it provides great results. But it seems to me to be a thing to be used in a specific way rather than a general way.




Edited by keith_h - 03 December 2021 at 02:04
Back to Top
Dyxum main page >  Forum Home > Dyxum Photographs > Themed Views Page  <1 1617181920 33>

Forum Jump Forum Permissions View Drop Down



This page was generated in 0.063 seconds.

Monitor calibration strip

Dyxum.com - Home of the alpha system photographer

In memory of Cameron Hill - brettania

Feel free to contact us if needed.