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04-17-2013, 03:14 PM - 1 Like   #91
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HA HA - Wrong wrong
Just went to pentax Australia to order a FA 31 & 77 and over night they added the silver 77 that wasn't there yesterday - now that does not sound like a lenses being discontinued. By the way got them in black although I would love love them in sliver. No problems hiding the black from the wife - serious issue with silver.

04-17-2013, 07:29 PM - 1 Like   #92
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QuoteOriginally posted by Blue Quote
the insect compound eye has nothing analogous to it
The nanostructures I referred to appear on lepidopterans - specifically nocturnal moths rather than diurnal. However this discussion on insects isn't the point - the natural nanotech optical AR technique used has nevertheless caught the attention of optical designers - Aero bright is biologically inspired- but is structurally not the same: the porosity of the aerogel is used to reduce the abruptness of the density change at the air/glass interface - when two materials of differing density meet there is a reflection at the point of contact - the silica aerogels inherent low density and extreme porosity is used as a buffer to reduce this effect. The thickness of the aerogel has to be carefully tuned for maximum effect in the visible light spectrum, but when tuned correctly it would be far more effective than other AR coatings - most AR coatings can only target a specific area of the visible spectrum.
04-18-2013, 08:44 PM   #93
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QuoteOriginally posted by Digitalis Quote
The nanostructures I referred to appear on lepidopterans - specifically nocturnal moths rather than diurnal. However this discussion on insects isn't the point - the natural nanotech optical AR technique used has nevertheless caught the attention of optical designers - Aero bright is biologically inspired- but is structurally not the same: the porosity of the aerogel is used to reduce the abruptness of the density change at the air/glass interface - when two materials of differing density meet there is a reflection at the point of contact - the silica aerogels inherent low density and extreme porosity is used as a buffer to reduce this effect. The thickness of the aerogel has to be carefully tuned for maximum effect in the visible light spectrum, but when tuned correctly it would be far more effective than other AR coatings - most AR coatings can only target a specific area of the visible spectrum.
I know it is not the same structurally and functionally to insects which is why I pointed out the insect part which you brought up. All I did was state the Pentax coatings and nothing more. What I attempted to point out way back is the the FA ltd lenses and DA ltd lenses got Ghostless Coatings. I also brought up Pentax's newer coatings. Nothing I posted was inaccurate and was from Pentax sources. If you have access to Pentax information regarding Aero Bright or HD, it would be interesting to see. So would some of the older tech such as the Tak and Super Tak coatings.

Edit: On a separate note, I have wondered how a set of FA LTD would work redone with Aero Bright. It would probably give them a different character, but it would be interesting optically.
06-07-2013, 08:50 PM   #94
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It would be nice if the FA Limited Primes plus my 100mm Macro, the one built like a tank not the plastic one, would work with a medium format super high resolution camera and also work with my AF540 flash. If they had something like that I'd sell my K5 and K10D and buy my last camera...and used that until I turned into worm food. If they don't I think I'd invest in one more DSLR and use that until I die.

06-07-2013, 09:10 PM   #95
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But... they won't work with a MF camera. If you'd like well built MF lenses, they're out there.
06-07-2013, 11:33 PM   #96
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QuoteOriginally posted by ElJamoquio Quote
But... they won't work with a MF camera. If you'd like well built MF lenses, they're out there.
But maybe they cover a bigger circle, like DAs cover FF. The not-FF (according to 60 x 45 MF) 645D-sensor is just 44 x 33 mm. Not so big difference. Of course you cant use them on a MF-camera built with much longer flangedistance. I think the mirror will hit the lens. There are rangefinders without mirror though, but I think you fould the lens out so you got a long "flangedistance" on them to. Guess also that its easier to build a good MF-lens if you have that space between. But they might get better at constructing lenses for small flangedistance now with the mirrorless revolution ahead. Leica has rather good lenses for FF Ive heard also.

Last edited by mrmentera; 06-08-2013 at 02:27 AM.
06-08-2013, 07:56 AM   #97
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QuoteOriginally posted by mrmentera Quote
But maybe they cover a bigger circle, like DAs cover FF. The not-FF (according to 60 x 45 MF) 645D-sensor is just 44 x 33 mm.
There are new standarts for digital MF. The film size is used only for calculation of crop-factor for lens and camera.
44*33 mm is 8 year old standart for MF sensors.

FA lenses cover 24*36 mm. Not bigger.

P.S. 645 film is 56*41.5 mm
06-08-2013, 07:58 AM   #98
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QuoteOriginally posted by mrmentera Quote
But maybe they cover a bigger circle, like DAs cover FF. The not-FF (according to 60 x 45 MF) 645D-sensor is just 44 x 33 mm. Not so big difference.
It's bigger than the difference between APS-C and FF, for what that's worth.

I think a MF sized sensor in a 'normal' DSLR sized body would be great. It would be the 645DII? though and cost quite a bit of money.

06-08-2013, 08:06 AM   #99
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QuoteOriginally posted by BlakeShellman Quote
It would be nice if the FA Limited Primes plus my 100mm Macro, the one built like a tank not the plastic one, would work with a medium format super high resolution camera and also work with my AF540 flash. If they had something like that I'd sell my K5 and K10D and buy my last camera...and used that until I turned into worm food. If they don't I think I'd invest in one more DSLR and use that until I die.
They have the D FA 645 line of lenses that are very good in their own right. There is the 90mm macro lens for the 645D.

HD Pentax-D FA 645 90mm F2.8 ED AW SR Macro

SMC Pentax-D FA 645 25mm F4 AL [IF] SDM AW



There is also


SMC Pentax-DA 645 25mm F4 AL [IF] SDM AW

The the digital medium format game comes down to money and the 645D is no exception but is competitively priced in that arena.
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