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04-17-2019, 07:26 PM   #1
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Figuring out what to do with my mirror lens.

A month or so ago, I got a Starblitz mirror/reflex lens from an estate sale. Always wanting to play around with one I snapped at the chance. Personally, I think the donut bokeh is kind of cool and fun, but damn is this lens soft. I understand not all lenses have to be tac sharp, but Iím really having a hard time figuring out ďwhat to do with this thingĒ. I put it on my K3 and shot the moon, but was extremely unhappy with the quality. Any suggestions of where/what kind of photography I can do, outside if extremely fuzzy shots of the moon?

04-17-2019, 08:06 PM   #2
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have not used the 500mm f8 mirror I have for years!!!...forget if it is rokinon or bower (most are the same)…..an ok paper weight I reckon....its a very difficult lens to focus to get anything 'sharp'.....following to see the suggestions and may even take it for another ride to experiment with
04-17-2019, 08:31 PM   #3
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Perhaps you could bring back the Pictorialism movement in photography.
QuoteQuote:
Typically, a pictorial photograph appears to lack a sharp focus
04-17-2019, 09:06 PM   #4
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You might want to check out the Mirror Lens Club, too, now up to 67 pages of donut bokeh goodness!. Lots of great shots,to show what some of these tiny telescopes can do.

04-17-2019, 09:23 PM - 1 Like   #5
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QuoteOriginally posted by Thagomizer Quote
You might want to check out the Mirror Lens Club, too, now up to 67 pages of donut bokeh goodness!.
They make my head hurt.
04-18-2019, 02:50 AM - 3 Likes   #6
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QuoteOriginally posted by bikehead90 Quote
A month or so ago, I got a Starblitz mirror/reflex lens from an estate sale. Always wanting to play around with one I snapped at the chance. Personally, I think the donut bokeh is kind of cool and fun, but damn is this lens soft. I understand not all lenses have to be tac sharp, but I’m really having a hard time figuring out “what to do with this thing”. I put it on my K3 and shot the moon, but was extremely unhappy with the quality. Any suggestions of where/what kind of photography I can do, outside if extremely fuzzy shots of the moon?
The problem with catadioptric lenses, aside from the funky out-of-focus highlights, is that many of them simply aren't very good. There are a few decent models from the likes of Tamron and Sigma, and a few good Soviet models, but the majority of lower-cost mirror lenses aren't great. That aside, they all benefit from tripod mounting (or fast shutter speeds) and accurate focusing (achieved using magnified Live View - focus peaking simply isn't sufficient). You'll probably find distant subjects will suffer some detail loss, so try shooting things that are closer to you... a few tens or hundreds of feet, rather than miles.

If you have a reasonable-sized garden, fixed position photography of birds and animals on feeders is one thing you might consider. You can set up your camera and lens on a sturdy tripod, then use magnified Live View to accurately focus on the feeder. You might take a few test shots of it so you can confirm and adjust focus as necessary. Then, wait for the critters to appear and shoot away.

Aircraft photography might be another application. Set yourself up at or near a local airport so you have a pre-focused view of a certain section of airstrip, then wait for aircraft to reach that point before triggering the shutter. Same idea for motorsports.

In all cases, keep the shutter speed high - at least 1 / focal length - and take multiple exposures to give yourself a better chance of keepers. Shoot raw. Images won't look tack sharp when pixel peeping, so expect to do some post-processing to increase local contrast and/or sharpness.

This was taken with my Soviet 3M-5CA (hand-held, but I was using a mirrorless camera with an EVF, so focusing was relatively easy):

04-18-2019, 03:29 AM   #7
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As BigMack says

with Mirror lenses, it very well may depend on which one you have - I found a Tamron Adaptall-2 SP 500mm F8 Mirror ( 55BB ) at a good price on Ebay

the equation of knowledge, experience and equipment truly applies here

you might find some useful info in this link

Mirror, Mirror ( in the lens ) eek ? ! ? - Page 3 - PentaxForums.com

and great examples of what can be done can be found by looking at the link provided by Thagomizer and this one as well:

Adaptall Mount Club (Tamron). - PentaxForums.com

Last edited by aslyfox; 04-18-2019 at 04:00 AM.
04-18-2019, 03:34 AM   #8
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I find that some long mirror lenses suffer a little from low contrast, but not so much in absolute resolution, you might want to look at boosting contrast in post processing because sharpness is a combination of resolution and sharpness,

04-18-2019, 05:57 AM - 1 Like   #9
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If you want to point that thing at the sky my suggestion for getting a better focus would be to use a bahtinov mask and focus using magnified live view until you get the correct diffraction spike pattern. Use a really bright star like Sirius when focusing but be sure you didn't pick a planet. Once focused correctly then point it at the moon or what ever other object you want in the sky. There is an online tool for generating one of the correct size and pattern. Using one of these will get you the best infinity focus you can.
04-18-2019, 06:28 AM   #10
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Try to add a long hood ( I use a 4" one) on the 300mm or 500mm mirror lens and you will see the difference.


However, as others mentioned, some mirror lens just can't deliver good photos...
04-18-2019, 07:11 AM   #11
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Most everything I was going to say has already been said. I carry an 800mm Samyang mirror for those very odd occasions when I really could use the extra magnification, just for a record shot (most wild birds). The main problem I run into is heat haze. Any detail much past 150yds can start to get lost in the shimmer on a warm day.
A lens hood really can make a big difference to contrast. My Tamron 500mm has one and with/without tests really show a difference, especially over water, where there's an extra amount of out-of-image brightness to be considered.
04-18-2019, 07:26 AM   #12
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Focusing can have its difficulties because of the very slow (high f-stop) nature of these. Autofocusing is near impossible so manual focusing should be used and is aided if your camera has a magnified Liveview mode or the like. Even with that, it can be touchy since the shake induced when focusing makes it difficult. That said, good focusing is important.

Any chance the lens needs cleaning. If you look through the back, is it clear without fog? Most CAT lenses are sealed but still, fine dust over time can get in.

The other points previously discussed are good and you can get an eyepiece adapter which would allow you to use the lens as an optical telescope (although with an inverted image), though if the lens is optically insufficient, that use might be compromised also.
04-18-2019, 08:08 AM   #13
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QuoteOriginally posted by kypfer Quote
Most everything I was going to say has already been said. I carry an 800mm Samyang mirror for those very odd occasions when I really could use the extra magnification, just for a record shot (most wild birds). The main problem I run into is heat haze. Any detail much past 150yds can start to get lost in the shimmer on a warm day.
A lens hood really can make a big difference to contrast. My Tamron 500mm has one and with/without tests really show a difference, especially over water, where there's an extra amount of out-of-image brightness to be considered.
Iíve never considered heat haze as something to look out for, but yeah, I can absolutely see that. I have a good with the Starblitz, but Iíd say itís an inch to an inch and a half at most.

---------- Post added 04-18-19 at 08:11 AM ----------

QuoteOriginally posted by Bob 256 Quote
Focusing can have its difficulties because of the very slow (high f-stop) nature of these. Autofocusing is near impossible so manual focusing should be used and is aided if your camera has a magnified Liveview mode or the like. Even with that, it can be touchy since the shake induced when focusing makes it difficult. That said, good focusing is important.

Any chance the lens needs cleaning. If you look through the back, is it clear without fog? Most CAT lenses are sealed but still, fine dust over time can get in.

The other points previously discussed are good and you can get an eyepiece adapter which would allow you to use the lens as an optical telescope (although with an inverted image), though if the lens is optically insufficient, that use might be compromised also.
Thereís a few specks of dust on the front element (which is why I try to avoid shooting a blue sky). Iíd like to clean it, but Iím unsure how to approach that. I highly doubt Windex is appropriate, but it stays on when I brush it off or use a blower.
04-19-2019, 07:33 AM - 1 Like   #14
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I love my Sigma 600mm f8. I picked it up earlier this year, and while I didn't have much use for it in the winter, now that I can head outside in relative warmth I find that I have no trouble at all finding subjects. The talk about Pictorialism higher up interested me because I hadn't considered if there was ever a really movement in the type of photography I like, but it saddens me to know that there's now a widely held belief that absolute sharpness is so important for a good photograph. For me, it's nice to have a lens where sharpness is practically not a variable at all, so you can focus purely on composition and subject matter. A little bit of local contrast boosting or dehazing is really all you need to process a mirror lens photo, and that's partly because of atmosphere anyway, which would be an issue with a great refractive lens too.

My advice is to just go for a walk with the lens and a tripod, and take it slowly. Look for small or distant things and see how it looks framed in live view. The field of view at these high focal lengths is so vastly different from our eyesight, that I find it's actually difficult not to find an interesting perspective. Focus in on your subject, let the DoF do its thing, and don't expect technical perfection. I think it's a lot of fun.

Last edited by StarTroop; 04-19-2019 at 08:05 AM.
04-19-2019, 07:45 AM - 1 Like   #15
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QuoteOriginally posted by StarTroop Quote
My advice is to just go for a walk with the lens and a tripod, and take it slowly. Look for small or distant things and see how it looks framed in live view. The field of view at these high focal lengths is so vastly different from our eyesight, that I find it's actually difficult not to find an interesting perspective. Focus in on your subject, let the DoF do its thing, and don't expect technical perfection. I think it's a lot of fun.
Of all the advice, this might be the most intriguing Iíll use it more before I pass judgement.
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