[Laurentiu Cristofor]

First is that what the eye percepts as detail on a photo isn't the "lines per mm" but the "lines per frame" capacity of the lens.

You're assuming that FF sensors extract the maximum resolution out of their lenses, which is not true. Also, any lens will be sharper in the center than in the borders, so APS takes better advantage of the center sharpness of lenses than FF does. Just check the APS and FF reviews of the Canon 50mm f/1.2 on photozone for a practical example.

The second reason regards the size of the single "pixel" which for the same analysis (Mp) is (2/3x2/3 =4/9) less than half the area than it is on a FFsensor.

This is a valid point, but it happens only if the APS sensor offers the same resolution as the FF one. Which sadly is a goal that most manufacturers seem to pursue these days. But this is not an issue with the format as much as it is with its current implementation. I would expect that in time, trying to keep up to FF resolution will cease to be a goal, and FF and APS sensors will end up having photosites of similar size, with FF being the preferred format for those requiring extra resolution, the same way that MF cameras were preferred over 35mm cameras during film days.

[Marc Sabatella]

Hmmmmmmm - then all the togs around the world who use the 5d mk11, d700, 1dmk111, 1dsmk111 obviously are an unintelligent bunch - you reckon that they should become more informed and switch to a Pentax 20D/K7?

The question isn't whether or not there is some advantage to FF - no one is denying that FF *does* have advantages. We're just questioning the extremely simplistic and very misleading (to the point of the just being flat out wrong) analysis in the OP.

To also say that you cannot see the difference between a 5d mk11 d700 file on a 24" monitor needs serious re-consideration - well my eyes are not deceived - thats for sure.

There might be differences, but whether they are relevant to this discussion is an entirely different matter.

[jeffkrol]

I was referring to the old lenses on FF. I've heard of some vignetting at wider apertures but I don't whether that is on certain lenses or whether it is more extensive.
I've always considered it an advantage to using FF lenses on a cropped sensor in that they reduce the chance of edge softness in the image.

All you need (for any format) is a lens that adheres to this principal.
"just about every sensor I've ever worked with is "happy" as long as you're within 15 degrees."
and
Now, I've never measured the exit pupil of the Canon 17-35mm f2.8, but the Canon design is similar to the Nikon 17-35mm f2.8, and I have had that on the optical bench. For the Nikon, the exit pupil is 98.0mm at 17mm. This will cause no problems for a sensor with microlenses. It also tells you nothing whatsoever about how the camera will perform with lenses like a 20mm f2.8 (exit pupil at 53mm) or a 50mm f1.8 (exit pupil at 54mm).
Comparison test for vignetting: EOS 3 vs 5D vs 1Ds II - Photo.net Canon EOS Forum
It's not the age of the lens but the design..........
More on the idea:
Rafael - "How come my 1997 full frame film Camera with 20mm lens did not vignet"

Because film isn't particularly sensitive to the exit pupil location of the lens. The common Canon or Nikon 20mm f2.8 has an exit pupil about 52mm from the film plane, and the image circle radius of 35mm film is 21.6mm (sqrt(24^2+36^2)/2). So light strikes the corners of the image at 22 degrees (arctan(21.6mm/52mm)) from perpendicular. That doesn't bother film at all. Heck, film isn't even troubled if you have a 20mm rangefinder lens, with an exit pupil just 20mm from the film plane, and light striking 47 degrees (arctan(21.6mm/20mm) from perpendicular.

But digital is different than film. Due to the microlenses, a typical digital sensor has about a full stop less sensitivity to light 22 degrees from perpendicular than it does to light that actually is perpendicular to the sensor. So you get an extra stop of vignetting in the corners, added to whatever vignetting the lens already has.

Other wide designs have "better" exit pupil locations. A 24mm f1.4 is out more than 80mm from the film plane. So the angle is something like 15 degrees from perpendicular, and the vignetting is less than 1/3 stop
Of course some say it's just the same as film..
http://photo.net/canon-eos-digital-camera-forum/00Gtq2
http://www.openphotographyforums.com/forums/archive/index.php/t-331.html
but it is still in agreement w/ the first ones (sort of)
Andy, sometimes it's not the exit pupil location. Film or digital, the 17-40mm is simply not one of Canon's finer moments in lens design. Light falloff might simply be from a narrow optical path.

[GeneV]

I think I've completed a full-circle.

Started out with aps-c because it was 'good enough' for my level of experience,
then lusted after FF because I wanted 'more', and now, I'm fully realizing the
benefits of a high-quality smaller system - having the equipment with me because
it isn't a pain to lug around is 99% more important than the slight IQ boost a FF kit
would bring me.

Now I'm even starting to think about things like the GF1 or EP2 more than FF.


.

I'm with you on that Lowell. The most useless camera you can possibly own is the one you don't carry. I went through a circle as well. Film days lugging 3 or more bodies in a Tenba bag that could double for sleeping, to minimalism with an Olympus clamshell, to a Coolpix 880 and to the DSLR. One body (no need for bodies with various flims and speeds) made the SLR attractive again. Now the K-x and pancake lenses are really hitting the spot where the DSLR goes everywhere. A FF would definitely have its uses, but I would never want to give up the freedom of the current format.

[GeneV]

All you need (for any format) is a lens that adheres to this principal.
"just about every sensor I've ever worked with is "happy" as long as you're within 15 degrees."
and
Now, I've never measured the exit pupil of the Canon 17-35mm f2.8, but the Canon design is similar to the Nikon 17-35mm f2.8, and I have had that on the optical bench. For the Nikon, the exit pupil is 98.0mm at 17mm. This will cause no problems for a sensor with microlenses. It also tells you nothing whatsoever about how the camera will perform with lenses like a 20mm f2.8 (exit pupil at 53mm) or a 50mm f1.8 (exit pupil at 54mm).
Comparison test for vignetting: EOS 3 vs 5D vs 1Ds II - Photo.net Canon EOS Forum
It's not the age of the lens but the design..........
More on the idea:
Rafael - "How come my 1997 full frame film Camera with 20mm lens did not vignet"

Because film isn't particularly sensitive to the exit pupil location of the lens. The common Canon or Nikon 20mm f2.8 has an exit pupil about 52mm from the film plane, and the image circle radius of 35mm film is 21.6mm (sqrt(24^2+36^2)/2). So light strikes the corners of the image at 22 degrees (arctan(21.6mm/52mm)) from perpendicular. That doesn't bother film at all. Heck, film isn't even troubled if you have a 20mm rangefinder lens, with an exit pupil just 20mm from the film plane, and light striking 47 degrees (arctan(21.6mm/20mm) from perpendicular.

But digital is different than film. Due to the microlenses, a typical digital sensor has about a full stop less sensitivity to light 22 degrees from perpendicular than it does to light that actually is perpendicular to the sensor. So you get an extra stop of vignetting in the corners, added to whatever vignetting the lens already has.

Other wide designs have "better" exit pupil locations. A 24mm f1.4 is out more than 80mm from the film plane. So the angle is something like 15 degrees from perpendicular, and the vignetting is less than 1/3 stop
Of course some say it's just the same as film..
Comparison test for vignetting: EOS 3 vs 5D vs 1Ds II - Photo.net Canon EOS Forum
Vignetting on Full-frame sensor quantified (with 2 lenses) [Archive] - Open Photography Forums
but it is still in agreement w/ the first ones (sort of)
Andy, sometimes it's not the exit pupil location. Film or digital, the 17-40mm is simply not one of Canon's finer moments in lens design. Light falloff might simply be from a narrow optical path.

I learn something new every day I check this forum. Thanks!

[pniauris]

Gentlemen I thank you all for the time you spent to answer to me , but I think I have been misunderstood . May be the maths ... Well I expect to be a better photographer , not BYING "better" gear as Mr. "flyer" supposes , but trying to get
as much potential as I can from the already owned . That's what my teacher in a
photography school had taught me back in 1985 , when I was shooting with an all plastic Lubitel 122(?) 6x6 , the absolutely cheapest camera in the market then ,
which I used as an enlarger as well .
He also told me "crop as less as possible" but by now I have to crop all the time ("cropping around " sounds perfect ).
Anyway my point is this : A 500 euro APS-C lens of today can hardly beat a 30 euro Mir-1 or Jupiter 37a if the last ones weren't penalised by cropping . I would
cheat if I refered the K's,M's,A's,Tak's,Flectogons,Sonnars and so on , that play in "A" class for 100-200 euros .
THAT'S WHY I would like an FF
As about Mr. Shashinki who says he is nearsighted , no , my friend , medium format isn't the solution to your problem but think about MACRO .This is the thing for you .

[Laurentiu Cristofor]

Anyway my point is this : A 500 euro APS-C lens of today can hardly beat a 30 euro Mir-1 or Jupiter 37a if the last ones weren't penalised by cropping.

Yes, those lenses are horrendous on APS sensors - the sensors totally "outresolve" them. The horror, the horror!

[little laker]

pniauris,
If you pass me a K100D, with a 18 - 55mm kit lens I can offer you better, and more consistent results than most photographers shooting with high budget systems can offer. (that is shooting with comparable focal lengths)
That's without ever having taken a photography lesson.
The main reason why, is because I have the desire to be the best, at what I do.

I have been offered the chance to shoot just about anything that I want to, at a substantial discount. I still chose a APS camera. Like others have said, it's smaller than the full frame cousins, and you really don't want the extra weight where I travel.
The one place where I'd like a full frame camera is in a tight studio, but them again I have a few lying around here. They just take film rather than memory cards... which is fine by me, especially since I can develop my own work.

I have been ridiculed for my choice in cameras, however when they've seen my work everyone who's talked down to me has eaten their words.

[PentaxPoke]

We've gone through similar discussions many times before.
You may want to read through this comprehensive thread:
https://www.pentaxforums.com/forums/pentax-dslr-discussion/71896-low-noise-be...uals-zero.html

Why do I want Pentax to make a FF camera? So that there are no more new threads here titled "I want a FF camera"

[jct us101]

Why do I want Pentax to make a FF camera? So that there are no more new threads here titled "I want a FF camera"

Then we'd get ones complaining about the things that the FF camera doesn't have though.

[Marc Sabatella]

I expect to be a better photographer , not BYING "better" gear as Mr. "flyer" supposes , but trying to get
as much potential as I can from the already owned .

Take 100 shots each with an APS-C and FF camera. If you can reliably tell the difference just by looking at the images which came from which camera, I'll buy both of them for you.

Anyway my point is this : A 500 euro APS-C lens of today can hardly beat a 30 euro Mir-1 or Jupiter 37a if the last ones weren't penalised by cropping .

Some cheap lenses do indeed outperform some expensive ones. And the revrse is just as surely true. What does any of that have to do with APS-C versus FF?

[GeneV]

Then we'd get ones complaining about the things that the FF camera doesn't have though.

We can still complain about the autofocus.

[jogiba]

The #1 reason I want a FF DSLR is for the much wider FOV from my FF lenses and have them work like on a 35mm SLR again.

[WillCarney]

The #1 reason I want a FF DSLR is for the much wider FOV from my FF lenses and have them work like on a 35mm SLR again.

BINGO, give that man a cigar.

William

[krypticide]

Possiblity of shallower depth of field!