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03-03-2016, 08:13 AM   #241
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QuoteOriginally posted by Simen1 Quote
For the bokeh club, yes. For us BoB shooters (Bird on Branch) we often find uniform blu sky behind our subjects.
Bokeh is of no concern if optical quality is down the toilet.
You know the story about the pig and the lipstick, right?

03-03-2016, 08:18 AM   #242
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Vivitar Series 1 Solid Catadioptric Mirror Lenses (Perkin Elmer - as in Hubble)

Solid Cat Luminous Landscape

Last edited by monochrome; 03-03-2016 at 09:14 AM.
03-03-2016, 08:51 AM   #243
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QuoteOriginally posted by D1N0 Quote
But those aren't very light
Some are actually weightless!
03-03-2016, 12:29 PM   #244
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When I see claims about something I step back and think about the economics. In other words, follow the money. Humans are capitalistic (mostly) if there is a way to make some money someone will do it.

So when I see things like
QuoteQuote:
A mirror lens is not a bad idea, its just historically poorly conducted.
I have to be skeptical because these lenses have been around for a long time. The principles are understood. Yet no one has ever made one that is of good enough quality to make people buy them instead of far, far more expensive and heavier lenses. I have to wonder why that is. We are talking about potentially a lot of money, with regular 500mm lenses costing $3,000-5,000 there is a lot of room for someone to make a $1,000 mirror lens that performs almost as well. But they have not. So I suspect it is because they could not.

03-03-2016, 12:52 PM   #245
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QuoteOriginally posted by thibs Quote
Bokeh is of no concern if optical quality is down the toilet.
You know the story about the pig and the lipstick, right?
If the optical quality are in the toilet for mirror lenses, thy are mirror astronomic telescope in use?
You don´t want a 2-3 kg tele lens for $$$ then you walkaround or travel light, a limited mirror lens as 400/,5,6 for 800-1000€/$
can be a good lens for specific occasion even with bad bokeh.
03-03-2016, 01:08 PM   #246
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QuoteOriginally posted by ogl Quote
Rather heavy lens. 405 gram. the same weight as DA18-135
Both of which I have, and neither of which I would have regarded as heavy, but I accept the figure you quote. Maybe I've just got used to having heavier lenses on my cameras.
03-03-2016, 01:25 PM   #247
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Here is some users about Minolta/Sony 500/8 mirror lens:
Minolta AF Reflex 500mm F8 A-mount alpha lens reviews
03-03-2016, 02:16 PM   #248
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QuoteOriginally posted by Bophoto Quote
If the optical quality are in the toilet for mirror lenses, thy are mirror astronomic telescope in use?
You don´t want a 2-3 kg tele lens for $$$ then you walkaround or travel light, a limited mirror lens as 400/,5,6 for 800-1000€/$
can be a good lens for specific occasion even with bad bokeh.
They don't care about bokeh. Also mirrors don't do colour fringing and it is just a economic decision. A mirror telescope is much cheaper and more practical than one made of glass elelements.

03-03-2016, 03:12 PM   #249
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Bokeh can be dealt with sometimes. Just choose a nice smooth background without any details to be messed with.

For me a heavy and expensive tele lens just isn’t an option, regardless of qualities. A mirror lens would be the only way for me, and I'm quite sure there is much that can be improved a lot. WR, AF, ND filter wheel coupled to the aperture leaver, hood, baffles and maybe even a doughnut free design. I will also add a back polarizing filter to reduce the effect of air humidity and smog on sunny days.
03-04-2016, 12:55 AM   #250
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QuoteOriginally posted by Simen1 Quote
Bokeh can be dealt with sometimes. Just choose a nice smooth background without any details to be messed with.

For me a heavy and expensive tele lens just isn’t an option, regardless of qualities. A mirror lens would be the only way for me, and I'm quite sure there is much that can be improved a lot. WR, AF, ND filter wheel coupled to the aperture leaver, hood, baffles and maybe even a doughnut free design. I will also add a back polarizing filter to reduce the effect of air humidity and smog on sunny days.
Yeah a 400mm lens on an FF typically used in studio with a nice background. a 400mm lens never used to shoot, birds, wildlife or sport were the you don't have that much choice for the background.

This is funny how in one thread a large camera can have very small lenses and how in the next thread then you have to severely compromize the quality of picture to get a lens with fixed apperture, no AF, bad bokeh and so-so sharpness to keep something not to big.

Reality is that if you take a DA*300 f/4, on APSC, you get 420mm f/5.6 equiv and you have only 800g and 850$ to spend to get it. It is not 3000-5000$, it has variable apperture, AF, great bokeh and reasonnably compact.

A DA*200, (that still cover FF) is a bit lighter, significantly shorter, give the same light gathering and would still provide 16-20MP on an m4/3. This could be designed, likely a bit smaller than it is no today as the image circle doesn't have to be the same.

But no, sensor size doesn't change anything to size/weight... as long as you stick to no AF, fixed apperture, crap bokeh, low sharpness mirror lenses. Thank you for your insights !
03-04-2016, 01:54 AM   #251
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If the sky is consistently blue or cloudy and the mountains surrounding you peek at 5 degrees above the horizons in all directions you still have 170 degrees of nice studio background over you. You just need to place yourself so there are no trees or buildings in the way in front of or behind the subject.

I don’t see any inconsistency in wanting to keep the weight of the total system down and wanting to shift the priority of weight from lenses to the camera. As I said in both examples and theory Its consistent with the wish for better image quality both in terms of resolution and noise.
03-04-2016, 01:54 AM   #252
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QuoteOriginally posted by Nicolas06 Quote
This is funny how in one thread a large camera can have very small lenses and how in the next thread then you have to severely compromize the quality of picture to get a lens with fixed apperture, no AF, bad bokeh and so-so sharpness to keep something not to big.
Kind of funny how the Pentax has produced a 400 F5.6 in the past, that is only 70 g heavier and 15mm longer than the DA 300 F4 and I am willing to bet that it has AF good boken, is sharp and not going to cost 3000 - 5000 for a new version if it was ever released
I bet you if I look up Canikon lenses in the same FOV and 5.6 that they would be in about the same category as the DA 300 F4 with the weight difference being more depended on the design of the lens and not the format size the lens is for.

QuoteOriginally posted by Nicolas06 Quote
A DA*200, (that still cover FF) is a bit lighter, significantly shorter, give the same light gathering and would still provide 16-20MP on an m4/3. This could be designed, likely a bit smaller than it is no today as the image circle doesn't have to be the same.
QuoteOriginally posted by Nicolas06 Quote
But no, sensor size doesn't change anything to size/weight... as long as you stick to no AF, fixed apperture, crap bokeh, low sharpness mirror lenses. Thank you for your insights !


Again the design has more of a role in the size and weight for a given FOV and DOF than the difference between formats, just like the new nikkor 300 F4 its 70 g lighter and only 13mm longer than the DA 200 F2.8
03-04-2016, 02:33 AM   #253
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QuoteOriginally posted by Nicolas06 Quote
Yeah a 400mm lens on an FF typically used in studio with a nice background. a 400mm lens never used to shoot, birds, wildlife or sport were the you don't have that much choice for the background.

This is funny how in one thread a large camera can have very small lenses and how in the next thread then you have to severely compromize the quality of picture to get a lens with fixed apperture, no AF, bad bokeh and so-so sharpness to keep something not to big.

Reality is that if you take a DA*300 f/4, on APSC, you get 420mm f/5.6 equiv and you have only 800g and 850$ to spend to get it. It is not 3000-5000$, it has variable apperture, AF, great bokeh and reasonnably compact.

A DA*200, (that still cover FF) is a bit lighter, significantly shorter, give the same light gathering and would still provide 16-20MP on an m4/3. This could be designed, likely a bit smaller than it is no today as the image circle doesn't have to be the same.

But no, sensor size doesn't change anything to size/weight... as long as you stick to no AF, fixed apperture, crap bokeh, low sharpness mirror lenses. Thank you for your insights !
I take back the mirror lens for FF, had it in my head for some time, but for APS. And for APS it could be a hit.
03-04-2016, 03:39 AM   #254
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This FF mirror lens may have been mentioned in this thread, but if so (sorry) I missed it:

SMC Pentax 400-600mm Reflex
03-04-2016, 04:36 AM   #255
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I like that one! (400-600mm f/8-12)

And I would like even more a heavily modernized version with WR, AF, back CPL filter, HD coatings and a large hood.
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