Mirror lenses!

Given the DOF seen in both, the f-stops were not the same -- again apple vs orange.

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/

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.    

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

Any lens has a focussing helicoid that needs lubrication. Grease can deteriorate and run to places where it doesn't need to be.

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

Read this.

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