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09-21-2015, 11:59 PM   #46
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QuoteOriginally posted by 672 Quote
I am talking about a 24x36mm sensor that will make "limiteds" look like a dirty old window is between the sensor and your subject……….
You should have a look at what Pinholecam and others have done with a wide range of Pentax lenses on Sony A7 series, you might be amazed...https://www.pentaxforums.com/forums/122-lens-clubs/247282-pentax-lenses-ff-club-36.html

31mm on Sony FF by Pinholecam


<Pinholecam's images taken from the Pentax Lenses on FF club >

Now, who would want lens performance like that on digital FF....time to throw all the 'old' designs in the trash! /sarc


Last edited by Deimos; 09-22-2015 at 12:12 AM.
09-22-2015, 12:26 AM   #47
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QuoteOriginally posted by reh321 Quote
When, "just for kicks", I mounted the 50mm kit lens from my 1984 Pentax Super Program on my "new" Pentax K-3o, I was amazed how sharp that lens is. I had assumed that the superiority of my new digital images over my old Kodachrome 25 slides was a result of the lenses I was using back then, but I have had to rethink my understanding of how the sharpest slide film compared to even pedestrian sensors today. I would not be surprised if 30-year-old lenses are just fine for the newest camera - if you're taking landscape type pictures, the DOF I've experienced with that lens means that manual focusing may not even be much of an issue.
I use a 50mm f/1.4 SMC-M which works perfectly fine on my K3 and outresolves the sensor when stopped down to f/2.8-f/4 (I have sometimes some demosaicking artifacts so it means that the resolved spacial frequencies are at Nyquist frequency). I have also a 35mm and 85mm SMC that are decent but not as good.
I know that for the wide angles some film era lenses are designed based on the non-flatness of the film. These lenses should not work well on digital.
On the telephoto side the main limit is the glass. The low dispersion glass have a very good impact on chromatic aberration. In fact in telephoto lenses the design is one converging lens group, then a lot of space and a second divergent lens group plus other lenses for aberration correction. The issue around chromatic aberration comes mainly from the first lens group, which often benefits from low dispersion glass.
Last item of modern design : aspheric elements. That is a great feature but it should mainly benefit to wide aperture (under f/2.8-f/4) and zoom lenses.
09-22-2015, 02:30 AM   #48
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QuoteOriginally posted by Deimos Quote
You should have a look at what Pinholecam and others have done with a wide range of Pentax lenses on Sony A7 series, you might be amazed...https://www.pentaxforums.com/forums/122-lens-clubs/247282-pentax-lenses-ff-club-36.html

31mm on Sony FF by Pinholecam


<Pinholecam's images taken from the Pentax Lenses on FF club >

Now, who would want lens performance like that on digital FF....time to throw all the 'old' designs in the trash! /sarc
Lovely images. Pentax lenses deliver, and raise the value of A7 cameras, because Sony's range of lenses for the A7 line of cameras are an utter cr@p.
So while people justify buying mediocre to boring Sony cameras to use with their Pentax FF lenses, Pentax postpones their FF launch by another half a year, enticing more people to buy A7.
What an absentmindedness.
09-22-2015, 03:08 AM   #49
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I think we can safely say that old lenses will be usable on a new full frame camera, but that they may have weak borders and vignette. There will be no automatic lens corrections for most of these lenses (probably the FA limiteds will have lens corrections built in). For a lot of photos, weak borders and vignetting will not be problematic at all. Pinhole has centered his sons enough in these shots and shot with little enough depth of field that it is hard to say much about the borders on these images. If you are shooting landscape, it is doubtful if you would shoot wide open on any lens -- old or new. Much more likely to shoot at f8 to f11 as you usually want maximal depth of field. This will likely fix a lot of the border issues that people mention in these lenses.

That said, clearly Pentax is working on new lenses and I would expect the new zooms they come out with to be a significant step above older zooms. Zooms have come a lot farther over the years than have primes. I suppose a lot of older lenses will be a little more prone to flare and have less contrast due to older lens coatings (although Pentax has always had the best lens coatings on the market for a given era).

09-22-2015, 05:24 AM   #50
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QuoteOriginally posted by Deimos Quote
You should have a look at what Pinholecam and others have done with a wide range of Pentax lenses on Sony A7 series, you might be amazed...https://www.pentaxforums.com/forums/122-lens-clubs/247282-pentax-lenses-ff-club-36.html

31mm on Sony FF by Pinholecam


<Pinholecam's images taken from the Pentax Lenses on FF club >

Now, who would want lens performance like that on digital FF....time to throw all the 'old' designs in the trash! /sarc
Pretty sharp. Nice shots
09-22-2015, 05:37 AM   #51
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QuoteOriginally posted by rawr Quote
That will be news to those Sony A7R users who have mounted many an 'old' Pentax lenses on their 36MP camera, and reported good results ...
Not to mention that glass even older than that still works just fine...
09-22-2015, 11:41 PM   #52
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It's up to anyone's choice to decide changing legacy glass and spend more money or wait-wait-wait before buying new lenses ; for some qualitative improvements that remain to be seen, related to their use or target...
For the time being, my old lens army awaits for the FF body...

Last edited by Zygonyx; 09-22-2015 at 11:50 PM.
09-23-2015, 12:07 AM   #53
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Oh my ! It will have a Polaroid back and integrated 36 MP scanner !!!!!!!

09-23-2015, 07:18 AM   #54
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QuoteOriginally posted by Rondec Quote
I think we can safely say that old lenses will be usable on a new full frame camera, but that they may have weak borders and vignette. There will be no automatic lens corrections for most of these lenses (probably the FA limiteds will have lens corrections built in). For a lot of photos, weak borders and vignetting will not be problematic at all. Pinhole has centered his sons enough in these shots and shot with little enough depth of field that it is hard to say much about the borders on these images. If you are shooting landscape, it is doubtful if you would shoot wide open on any lens -- old or new. Much more likely to shoot at f8 to f11 as you usually want maximal depth of field. This will likely fix a lot of the border issues that people mention in these lenses.

That said, clearly Pentax is working on new lenses and I would expect the new zooms they come out with to be a significant step above older zooms. Zooms have come a lot farther over the years than have primes. I suppose a lot of older lenses will be a little more prone to flare and have less contrast due to older lens coatings (although Pentax has always had the best lens coatings on the market for a given era).
A good explanation of why legacy lenses may not be as good on digital:

sensors

The pertinent comment, from that article, is:
"if photosites are above 8 micron then high quality legacy 35mm lenses are likely to be adequately matched in resolution terms.
BUT if photosites are less than 7-8 micron, then the lenses may be the limiting factor in resolution, especially zoom lenses and dedicated lenses designed for digital may be required to get the most out of the sensor (hence Olympus ZD lenses)."
09-23-2015, 07:29 AM   #55
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QuoteOriginally posted by K David Quote
It just occurred to me that the prototype was shown with an FA Limited 31mm lens at the unveiling earlier this year.
Sufficient data to infer it will have screw drive.
09-23-2015, 08:22 AM   #56
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QuoteOriginally posted by Canuck_west Quote
A good explanation of why legacy lenses may not be as good on digital:

sensors

The pertinent comment, from that article, is:
"if photosites are above 8 micron then high quality legacy 35mm lenses are likely to be adequately matched in resolution terms.
BUT if photosites are less than 7-8 micron, then the lenses may be the limiting factor in resolution, especially zoom lenses and dedicated lenses designed for digital may be required to get the most out of the sensor (hence Olympus ZD lenses)."
https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/303658-k-m-...ml#post3368817

The 24MP Pentax K3 has a pixel pitch of 3.88 microns
The 50MP Canon 5DS has a pixel pitch of 4.13 microns
The 16MP Pentax K50 has a pixel pitch of 4.78 microns
The 36MP Nikon D810 has a pixel pitch of 4.87 microns
The 10MP Pentax K10D has a pixel pitch of 6.07 microns

The K10 clearly doesn't resolve as well as the K3 even with legacy lenses yet is already using pixels far smaller than the 7-8 micro value specified in that article. The other thing to note is that if a legacy lens performs well on the K3 today - there is no reason to expect that the center performance will suffer on FF since the pixels are already smaller and more densely packed on even the K50 than a Nikon D810. The only real question as stated by another is will a given lens have poor border/corner performance and vignetting compared to expectations. CA and other issues should be similar to what A7 and Pentax users already see today - which is well within reasonable for many if not most legacy lenses.

This isn't to say there is no advantage to the newer lenses - it is just to calm Fear Uncertainty and Doubt before people do dumb things like dump their legacy glass anticipating a bonfire sale.

Lastly just to make a clear and concise point:
Smaller sensors require much better lenses than larger one's. Imperfections and minor aberrations are easier to ignore and have less impact on large sensors than small one's This was true in the film era and it is true today. I am not talking about the outliers like corner performance of poor lenses being revealed as the lens is asked to deliver a larger image circle - I'm talking in general about lenses designed for each sensor.
09-23-2015, 06:19 PM   #57
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QuoteOriginally posted by UncleVanya Quote
Lastly just to make a clear and concise point:
Smaller sensors require much better lenses than larger one's. Imperfections and minor aberrations are easier to ignore and have less impact on large sensors than small one's This was true in the film era and it is true today. I am not talking about the outliers like corner performance of poor lenses being revealed as the lens is asked to deliver a larger image circle - I'm talking in general about lenses designed for each sensor.
About big lenses and small sensor results ^^
https://www.pentaxforums.com/forums/136-pentax-q/209474-adapted-lenses-tested...ce-thread.html
09-23-2015, 07:28 PM - 2 Likes   #58
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Y'all just keep sellin' those SMC lenses from the 70's and your FA Limiteds and A* long lenses that can't resolve a FF sensor, thankyouverymuch.

Last edited by monochrome; 09-24-2015 at 04:36 AM.
09-24-2015, 06:09 AM   #59
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QuoteOriginally posted by monochrome Quote
Y'all just keep sellin' those SMC lenses from the 70's and your FA Limiteds and A* long lenses that can't resolve a FF sensor, thankyouverymuch.
Amen brother...
09-24-2015, 06:18 AM - 1 Like   #60
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Oh, no. Those antiquated FA Limiteds are damaging to the environment and must be disposed of properly - I'm willing to dispose them (in my bag) for a small fee*.

* I need money for the camera, right?
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