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07-10-2012, 10:29 AM   #16
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QuoteOriginally posted by Not a Number Quote
A lens hood is easy to improvise since the angle of view is around 5 or less. Just get a big enough piece of card stock and wrap it around the tube and hold in place with tape or a rubber band. Junk mail flyers work well. Trim or slide to avoid vignetting.
Not a great suggestion as most fliers are glossy and still bounce, now colored, light into the lens. A piece of flat black construction paper seems to work the best from what I've seen.

07-10-2012, 11:30 AM   #17
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Hey, next time I drive thru Indy I should stop by with my Vivitar non-mirror 500mm. We will have to go outside, though, as its minimum focus is much farther than your setup!
07-10-2012, 11:36 AM   #18
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QuoteOriginally posted by TER-OR Quote
Hey, next time I drive thru Indy I should stop by with my Vivitar non-mirror 500mm. We will have to go outside, though, as its minimum focus is much farther than your setup!
The rules will be simple..ten paces and then turn and draw!
07-10-2012, 11:37 AM   #19
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Mirror lenses can do better than that, but still not what the Sigma 150-500 can do!

Here is my equivalent test with a different mirror lens (made a while ago). Both using a heavy tripod, and Live View focusing, and 2 sec. timer, and remote release, and bag of chicken bones shaken at the sky...

Tokina 500mm/8 mirror (w/ hood!):
(Click to see full-size, 100% crop)



Sigma 150-500mm @500 f/8 (w/hood!):
(Click to see full-size, 100% crop)


07-10-2012, 11:41 AM   #20
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500mm Vivtar:
I gotta take that thing out more often.
07-10-2012, 11:48 AM   #21
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QuoteOriginally posted by panoguy Quote
and bag of chicken bones shaken at the sky...
Dang, I knew I was missing a critical step
07-10-2012, 11:50 AM   #22
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I like the Mirror picture better, bokeh is more like when I don't wear my glasses - very familiar somehow.
07-10-2012, 12:22 PM   #23
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QuoteOriginally posted by Docrwm Quote
I got a rubber 3-stage hood for mine
Done! Thanks for the tip. I also got a circular metal one too, looks about 3cm long, still could be useful. Be keen to see if they make a difference.

07-10-2012, 12:32 PM   #24
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In the FWIW department, my 80s era Tamron Mirror is as good as the zoom. Something is wrong, but it is not mirror lenses in general.
07-10-2012, 01:06 PM   #25
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There are good and there are bad lenses, whether it be mirrors or lenses inside. A mirror lens needs a good protection against stray light. The Tokina is a good example for an effective lens hood, which is basically just as long as the whole lens and the diameter is the same as the lens barrel. Keeping out stray light is a MUST for a mirror lens, not only because of the massive exposed front lens, but mainly because light can fall directly onto the sensor, if the internal baffle is too short. And the baffle is often too short, because an effective baffle leads to serious vignetting, which is also undesireable for a photographic lens.

But a loss of contrast by not using an effective lens hood is just one point. The other one is: a cheap mirror lens cannot be made to perform really good. This is an economic impossibility. Mirror lenses are quite complicated, even if the principle looks invitingly easy to produce. The surface roughness and the surface geometry of the primary mirror and the secondary must be made to quite exacting standards - really better than simple optical lenses. Also the mechanical construction is not easy, because the mirror mount needs to be stiff, but should not squeeze the mirror or the big front lens (a corrector lens), because you will get serious astigmatism, when any of these elements is "clamped" down too much (a common problem with the Russian made Rubinars). In Russia (or better in the Soviet Union) production cost did not translate into street price, because the economy worked differently (and crashed therefor). Thus the Soviet lenses could deliver really good quality at a diminutive price. A lens made in South Korea or by any Western maker cannot be cheap and good at the same time (see John Ruskin). The Samyang might be a example of that - at least according to the samples I see here.

Ben
07-10-2012, 01:32 PM   #26
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QuoteOriginally posted by Docrwm Quote
Not a great suggestion as most fliers are glossy and still bounce, now colored, light into the lens. A piece of flat black construction paper seems to work the best from what I've seen.
Some are glossy, some are not. For instance the Chinese restaurant down the street mails out these matte black flyers. Some #0 or #00 steel wool takes off the return address done in faux gold leaf lacquer. Steel wool will also dull down the lacquers or glossy inks used to print these things. Or you can use a matte finish or dulling spray.

Construction paper tends to be too flimsy but you could always put a card stock tube over it.

Anyway you get the idea - these can be easily and cheaply improvised.
07-10-2012, 01:39 PM   #27
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I have 4 mirror lenses and I found that a hood is mandatory. Two came with their own hoods and I got a metal 95mm 3" long for the others.


  • Tamron SP 500mm F8 (55BB): It has a dedicated reversible hood and by far has the greatest sharpness and most contrast of all. Can be used effectively as a "macro" lens since it can focuses closely while maintaining acceptable quality. It also performs OK with the 2X (01F) TC under very bright conditions.
  • Bower/Samyang 500mm F6.3: Quite acceptable contrast and much brighter than the rest.
  • Sigma 600mm F8: I probably have a defective copy; it is quite sharp but with very low contrast.
  • Spiratone 500mm F8: It has a built-in hood and a unique rendering quality; a bit soft and painterly.
I did some tests with and without a hood and the difference was very noticeable. All the lenses perform much better on a stable tripod with the 2s timer, and under good lighting conditions. The Tamron being the smallest is well suited for monopods or even handheld in bright days.

A boost in contrast and sharpness is almost necessary (unless one is looking for a soft dreamy image) in post processing.
07-10-2012, 02:49 PM   #28
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QuoteOriginally posted by Na Horuk Quote
I have read that mirror lenses are not very great, but this is still surprising. I never owned a mirror lens, but I really do wonder if this is just this particular lens or light conditions that caused such bad results.
Most aren't. The Russian Tair 3M-5CA and the Tamron 55BB are, though. I've never had the Tamron, but the Tair is very sharp & produces excellent images with good color and detail. I'm never getting rid of it. My wife's Tokina is ok, but the Tair is far better.

You also need to use a hood to get the best out of any mirror lens.
07-10-2012, 04:44 PM   #29
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As you state, the results are not a surprise. But I continue to be wowed by the 150-500 I purchased from you! And I'm actually relying on auto-focus more. In nature photography as in birds in trees or within brush a/f can be maddeningly impossible to use when framed on a multitude of planes.
07-10-2012, 04:50 PM   #30
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I have the Samyang (Rokinon branded) 500mm f/6.3 and the first thing I bought for it was a hood. The nice thing about the hood I got is that it is 95mm at both ends, so I could use the included lens cap. The hood is basically the same length as the lens, so that gives you an idea of how much stray light can get into a mirror lens and wash out the image. It's a pity these modern mirror lenses from Samyang aren't including hoods like the classic mirror lenses did, they really do need them.
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