Interesting article, with implications...

Cideway · 06-15-2008, 05:59 AM

Was lurking on DPR for the first time in a week, thanks for the well wishes by the way

, and i stumbled across this interesting article.

Do Sensors “Outresolve” Lenses?

Assuming i have read the article correctly it suggests that 15mp on a APS-C DSLR is the limit in terms of what the best lenses can resolve.

If this is in fact the case it would explain why my FA 50 f1.4 doesn't seem to perform in better, in terms of image resolution on my K20D then it did on my K10D. That the limit for that particular lens my lie some where between. While i noticed this with the 50 i did a test with my dad's FA 50 f1.4, as well as a M 50 f1.4 and a 1.7 and noticed no decernable difference in the lenses.

The comments about the higher quality lenses seems to track as i have noticed improvements with the FA limiteds and the 16-50 and 50-135 that shows the extra 50% resolution of the sensor on the K20D.

distudio · 06-15-2008, 06:50 AM

Originally posted by Cideway

Was lurking on DPR for the first time in a week, thanks for the well wishes by the way

, and i stumbled across this interesting article.

Do Sensors “Outresolve” Lenses?

That's a great read, very interesting and not at all surprising either. Thanks for pointing it out.

arbutusq · 06-15-2008, 07:49 AM

Fascinating if relatively incomprehensible.

regken · 06-15-2008, 09:09 AM

Thanks for the link. You gotta love LL for the quality of info they put out. If I reread it 3 or four more times I might start to understand it all. AN APC-S sensor might well be topped out at 14 or 15 MP's for most lenses. I wonder how the FA LTD lenses will fair on a 24MP FF sensor.

Ken

Adam67 · 06-15-2008, 10:48 AM

Originally posted by Cideway

Assuming i have read the article correctly it suggests that 15mp on a APS-C DSLR is the limit in terms of what the best lenses can resolve.

If I read correctly an APS-C sensor maxes out at 427MP's at f1.4 and a diffraction-limited lens......however at that aperture no such lens even exists. Now at f5.6 it maxes out at 27MP's but even here you are unlikely to ever come across a diffraction limited lens. At f11 it's 7MP's.

Where do most "real world" lenses fall as far as approaching diffraction limited class? Where do most zoom lenses fall?

It appears that raising the # of MP's in a APS-C sensor sized camera any further is entirely pointless.

It also appears that you would need to drastically increase the sensor size (like to 36x48 format) to see any real gains on increasing the megapixels.

Ole · 06-15-2008, 12:23 PM

Thanks for the reference! What is also interesting is one of the articles referenced:

Raw developers, sharpness and lens quality (sept 30, 2007) | Photography and image capture: the Leica technique and philosophy by Erwin Puts | Erwin Puts

As I understand this article the RAW processor (sharpening algorithms) is more important than the lens quality. The sharpening also affects the MTF and a consumer grade lens may be all you need if you know how to make the most out of the sharpening algorithms in your PP software!

I think I'll leave that heavy FA*80-200 behind and use my much more compact F 70-210 on my next photo trek!

flyer · 06-15-2008, 12:58 PM

When you look at an image on the K10D at 100 ISO, you wont find any other 10 meg. camera that can beat the image quality of said camera as far as noise is concerned. That might explain why it is so hard to see any difference with other camera with "improved" sensor. When I say that no other camera can touch the K10D at 100 ISO, those are the words of Kerrick James, a pro sponsored by Pentax, and a few reviewers from specialised mags.

06-15-2008, 05:59 AM	#1
Cideway Inactive Account Join Date: Feb 2007 Location: Adelaide, South Australia, Australia Photos: Gallery Posts: 364	Interesting article, with implications... Was lurking on DPR for the first time in a week, thanks for the well wishes by the way , and i stumbled across this interesting article. Do Sensors “Outresolve” Lenses? Assuming i have read the article correctly it suggests that 15mp on a APS-C DSLR is the limit in terms of what the best lenses can resolve. If this is in fact the case it would explain why my FA 50 f1.4 doesn't seem to perform in better, in terms of image resolution on my K20D then it did on my K10D. That the limit for that particular lens my lie some where between. While i noticed this with the 50 i did a test with my dad's FA 50 f1.4, as well as a M 50 f1.4 and a 1.7 and noticed no decernable difference in the lenses. The comments about the higher quality lenses seems to track as i have noticed improvements with the FA limiteds and the 16-50 and 50-135 that shows the extra 50% resolution of the sensor on the K20D.

06-15-2008, 09:09 AM	#4
regken Veteran Member Join Date: Sep 2006 Location: Bangor, Maine Photos: Gallery Posts: 1,377	A lot of info Thanks for the link. You gotta love LL for the quality of info they put out. If I reread it 3 or four more times I might start to understand it all. AN APC-S sensor might well be topped out at 14 or 15 MP's for most lenses. I wonder how the FA LTD lenses will fair on a 24MP FF sensor. Ken

06-15-2008, 12:23 PM	#6
Ole Administrator Join Date: Sep 2006 Location: Copenhagen, Denmark Photos: Gallery \| Albums Posts: 4,408	The sharpening algorithms also impact the MTF Thanks for the reference! What is also interesting is one of the articles referenced: Raw developers, sharpness and lens quality (sept 30, 2007) \| Photography and image capture: the Leica technique and philosophy by Erwin Puts \| Erwin Puts As I understand this article the RAW processor (sharpening algorithms) is more important than the lens quality. The sharpening also affects the MTF and a consumer grade lens may be all you need if you know how to make the most out of the sharpening algorithms in your PP software! I think I'll leave that heavy FA*80-200 behind and use my much more compact F 70-210 on my next photo trek!

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06-15-2008, 06:50 AM	#2
distudio Veteran Member Join Date: Jul 2007 Location: Sydney Photos: Albums Posts: 450	Originally posted by Cideway Was lurking on DPR for the first time in a week, thanks for the well wishes by the way , and i stumbled across this interesting article. Do Sensors “Outresolve” Lenses? That's a great read, very interesting and not at all surprising either. Thanks for pointing it out.

06-15-2008, 07:49 AM	#3
arbutusq Veteran Member Join Date: Sep 2006 Location: Vancouver BC canada Photos: Gallery Posts: 380	Fascinating if relatively incomprehensible.

06-15-2008, 10:48 AM	#5
Adam67 Forum Member Join Date: May 2008 Location: MI Posts: 62	Originally posted by Cideway Assuming i have read the article correctly it suggests that 15mp on a APS-C DSLR is the limit in terms of what the best lenses can resolve. If I read correctly an APS-C sensor maxes out at 427MP's at f1.4 and a diffraction-limited lens......however at that aperture no such lens even exists. Now at f5.6 it maxes out at 27MP's but even here you are unlikely to ever come across a diffraction limited lens. At f11 it's 7MP's. Where do most "real world" lenses fall as far as approaching diffraction limited class? Where do most zoom lenses fall? It appears that raising the # of MP's in a APS-C sensor sized camera any further is entirely pointless. It also appears that you would need to drastically increase the sensor size (like to 36x48 format) to see any real gains on increasing the megapixels.

06-15-2008, 12:58 PM	#7
flyer Veteran Member Join Date: Jan 2008 Location: Ste-Anne des Plaines, Qc., Canada Posts: 2,013	When you look at an image on the K10D at 100 ISO, you wont find any other 10 meg. camera that can beat the image quality of said camera as far as noise is concerned. That might explain why it is so hard to see any difference with other camera with "improved" sensor. When I say that no other camera can touch the K10D at 100 ISO, those are the words of Kerrick James, a pro sponsored by Pentax, and a few reviewers from specialised mags.