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02-14-2012, 06:55 AM   #2461
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I think the lens like it has "pixels in the glass". If you take a picture with APS-C camera with FF lens and 12Mp sensor, that means that you do not use the whole capacity of the lens, that area you use from the lens is about 44% of the full "lens pixel capacity". So to use the whole capacity of the lens the camera should be FF with about 27Mp sensor.
I know this is stupid explanation, but sounds understandable to me, I in a way modify the lens line writing capacity to pixels.
So my target is to show that there is most probably any possibilities to produce a FF lens which could fully match the resolution of an 100Mp sensor, there will always be a limit how many pixels a lens can get in use from a certain size of a sensor.
many have told that 24Mp in APS-C size is already too much, no lens can handle that high density sensor.
If the 24Mp is a limit for APS-C, then the same limits are 54Mp for FF and about 13,5Mp for m4/3, if I counted right.
Huh, I hope some one understand at least half of what I wrote

02-14-2012, 07:05 AM   #2462
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QuoteOriginally posted by markku55 Quote
Huh, I hope some one understand at least half of what I wrote
I think I did. However, you do a linear extrapolation which is too simple a thinking. Smaller sensors allow shorter registration distances and with smaller absolute apertures, tighter manufacturing tolerances. This is why P&Ss can exceed 10MP.

But higher resolutions require larger sensors. It's just not a simple or linear relationship. Moreover, it is actually a cost/performance curve with its sweet spot shifting to larger sensors with increasing MP.
02-14-2012, 09:00 AM   #2463
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QuoteOriginally posted by markku55 Quote
I hope some one understand at least half of what I wrote
Yes maybe about half, and I like your way of thinking about the "pixels in the glass." I need to let that bubble around in my brain for a while.

I do like my old lenses on my APS-C sensor, partly because (I think) the worst diffraction effects from the old glass don't seem to fall onto the effective pixels of the smaller sensor. Is this a correct assumption? Perhaps that is why the DA lenses are larger than they really need to be?
02-14-2012, 09:25 AM   #2464
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QuoteOriginally posted by falconeye Quote
But higher resolutions require larger sensors. It's just not a simple or linear relationship. Moreover, it is actually a cost/performance curve with its sweet spot shifting to larger sensors with increasing MP.
Well pixel density is greater now that it used to be, and I expect as cooler running, therefore less noisy electronics evolve, the sweet spot will shift back to smaller sensors and a more appropriate number of pixels.
But you are dead on. This is a cost/performance issue more than it is one of pure physics. We really don't need 24MP sensors to achieve the IQ we want. They exist solely because more pixels cost less (today) than cooler running technologies.

02-14-2012, 09:37 AM   #2465
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QuoteOriginally posted by sandilands Quote
I do like my old lenses on my APS-C sensor, partly because (I think) the worst diffraction effects from the old glass don't seem to fall onto the effective pixels of the smaller sensor. Is this a correct assumption? Perhaps that is why the DA lenses are larger than they really need to be?
Good points - although may I add and say "the worst diffraction from the old full frame glass.....
Much of the "cheap" (after-market and otherwise) FF glass I have would not work as well on a FF camera unless I could crop out the ugly bits
02-14-2012, 10:08 AM   #2466
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QuoteOriginally posted by markku55 Quote
Huh, I hope some one understand at least half of what I wrote
I think what you are looking for is a given lenses lp/mm (line pairs/millimeter) rating (the smallest a line pair can be while still being able to differentiate between the two), and to compare that to the sensel pitch on a given sensor.

For example, testing with a K-5 shows that the FA 43 1.9 can resolve 53 lp/mm in the center of the frame when stopped down to ƒ/5.6. Take this with a grain of salt however, as the K-5 has ~210 sensels per mm. The K-5 sensor is therefore able to resolve 105 lines per mm (52.5 line pairs) and thus the FA 43 out-resolves the K-5 sensor.

(Edit: the antialiasing filter, as it turns out, has little to nothing to do with the test results)

Last edited by RXrenesis8; 02-14-2012 at 05:05 PM.
02-14-2012, 11:46 AM   #2467
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I've often thought about removing the AA filter from my K-5 (I shoot landscape mainly anyways).. and for sharpness and IQ it probably would get my by.. still cropped FoV is not what I want for my FF glass.. I think this thread title should be renamed.. the end should be "They still aren't listening"
02-14-2012, 12:27 PM   #2468
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QuoteOriginally posted by Chex Quote
I've often thought about removing the AA filter from my K-5 (I shoot landscape mainly anyways).. and for sharpness and IQ it probably would get my by.. still cropped FoV is not what I want for my FF glass.. I think this thread title should be renamed.. the end should be "They still aren't listening"
I just learned that the hype of "cameras without AA filter" and cameras that have their AA filter removed is unfounded. The blurring that the AA filter applies is just enough to match the resolution of the sensor. So, without a AA filter the camera will not produce sharper images. Just adds moire and other artefacts. (Like in cellphone cams, that also don't have AA filters.)

But of course, I'm just a n00b that reads a lot, and this is just the latest story a "expert" told me. So please, correct me if I'm wrong.

02-14-2012, 12:41 PM   #2469
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You decide whether that's an appreciable difference... for most I think the reduced sharpness from the AAF is not that important, which is why the AAF is installed in the first place.
02-14-2012, 01:16 PM   #2470
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QuoteOriginally posted by ElJamoquio Quote
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You decide whether that's an appreciable difference... for most I think the reduced sharpness from the AAF is not that important, which is why the AAF is installed in the first place.
Yes, that changes things a lot. Has there been such a test with a K5 with it's AA filter removed? I can deal with some moire here and there, but unnecessary blur? No way!
02-14-2012, 01:58 PM   #2471
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QuoteOriginally posted by Clavius Quote
Yes, that changes things a lot. Has there been such a test with a K5 with it's AA filter removed? I can deal with some moire here and there, but unnecessary blur? No way!
the amount of blur is also camera model dependent. AA filter strength varies quite a bit from model to model from what i understand. Certainly if I was buying the D800 I would pay the extra for the E model (same cost as sending it out without voiding your warranty)

If this sells well for Nikon I think it will become a common feature option on the higher end and will be something a FF Pentax will want to offer.
I wouldn't have the conversion done until my warranty expired tough (if they offered it on the D7000 they could offer it on the Pentax i would think same sensor and all
02-14-2012, 02:10 PM   #2472
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The D800E costs more??!? What's the justification?
02-14-2012, 02:19 PM   #2473
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QuoteOriginally posted by eddie1960 Quote
If this sells well for Nikon I think it will become a common feature option on the higher end and will be something a FF Pentax will want to offer.
Well Pentax do offer the choice with 645D AFAICT
02-14-2012, 02:42 PM   #2474
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The K-5's filter is much stronger than the D7000's, yes the D7000 can show some moire is certain instances, but shooting mainly landscape it's far FAR less of an issue than having a stronger AA filter and loosing that extra sharpness. I am considering the D800E, but at the same time, with a 36MP sensor, when the picture is scaled to normal usable sizes, it would/should make up for the difference of AA filter or not. I would love to see if anyone has cut their AA filter from the K-5 and see the difference it has made.. If I end up keeping the K-5 I guess I could be the guinea pig and post some before and afters with it using the 43Ltd and a few others.. We'll see if my soon to be ex wants to take the K-5 or not.. if she does, it'll be D800 for me.
02-14-2012, 02:52 PM   #2475
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QuoteOriginally posted by RXrenesis8 Quote
For example, the FA 43 1.9 can resolve 53 lp/mm in the center of the frame when stopped down to ƒ/5.6. This means that it will match the resolution of a sensor that has 106 sensels every mm (53 line pairs = 106 lines). For APS-C this would result in a sensor with a resolution of 2480x1653 (4MP). Take this with a grain of salt however, as with most tests of this type it was performed with the highest performing camera of it's given mount (the K-5) and as the K-5 has an anti-aliasing filter to combat moire the results can never meet the resolution of the sensor!
Bear in mind that the K-5's pixels are arranged in groups of four, providing one colour pixel. So the K-5 only has about 4.2 colour MP (I'm right in thinking this yeah?).
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