[08amczb]

huh ?

Would you be a little more specific?

[Rondec]

Long story short, full frame will have a one stop advantage with regard to high iso performance (less noise, more dynamic range at the same iso levels). It may have a little better resolution as well. The more pixel dense the sensor, the harder it is to completely eliminate camera shake, subject motion etc that limit resolution. I definitely saw a little harder time hand holding when I went from the K5 II to the K3 camera.

[mee]

I would like to see 1:1 crops taken from a 24 MP APS-C camera and another crop from a 24 MP FF camera each using a similarly rated lens with equivalent FL and aperture. Is the detail in the FF noticeable? negligible?

[Rondec]

I would like to see 1:1 crops taken from a 24 MP APS-C camera and another crop from a 24 MP FF camera each using a similarly rated lens with equivalent FL and aperture. Is the detail in the FF noticeable? negligible?

I doubt there would be much difference. When I try to identify the difference between the two, I often cheat and use depth of field, as full frame images tend to have less of it. But if you are shooting at f8 or f11, then odds are things will be pretty even.

[Na Horuk]

Is the detail in the FF noticeable? negligible?

I think this would mostly be noticeable if you are taking photo in poor light conditions and then doing a lot of PP on it. Things like adding a lot of contrast, saturation, brightness can really push the limitations of the file. At that point, each bit, each pixel, each piece of noise counts.
But if you shoot under ISO6400, if you shoot in normal light conditions, if you don't do heavy PP, if you resize photos for web usage or print the size of postcard, then most people will not not notice any differences. Someone with motivation can train themselves to notice these differences and they might, if they take a closeup look and search for the indicators. But 99% of the audience does not do that

[CarlG]

huh ?

Totally agree!

[sqrrl]

I have a kp and use a canon 5d3 at work - that's probably a similar comparison - the big difference at non stupid iso levels is depth of field and how big the camera is.

Each has advantages depending on what you want.

Because a crop sensor is smaller it will use less of the image circle and will of course have a narrower field of view.

Less image circle means less aberrations/vignetting/blur in the corners assuming that you use the same lens on both cameras, thus the lens will be a bit sharper in the corners at a wide aperture.
Less field of view with the same number of pixels means higher resolution and effectively it seems like the lens is longer, handy sometimes.
Smaller sensor means greater depth of field - which is great if that is what you want.
It also means lighter glass, which I'm quite happy with.

On the other hand;
Larger sensor with the same number of pixels means each pixel is larger - thus it has greater odds of a photon (chunk o' light) hitting it, so the signal (image) needs less amplification (brightening).
Wider field of view means that a given lens seems wider, and thus a wide aperture has less depth of field than an equivalent field of view (wider) lens on a crop sensor. Bokeh!
It's easier to get wide angle lenses - though this is changing.
Looks more professional - like it or not, people expect pro's to have big cameras and glass and think amateurs use small cameras.

In practice, the real difference between a new kp and a 1-2 generation older full frame camera comes down to the FF has less depth of field for a given field of view, and the KP is most likely lighter and easier to carry (bokeh vs portability).

The difference is image quality is less pronounced than people might assume.

[K David]

What is the advantage of a full frame 24 mp camera over a 24 mp aps-c?

I don't think anyone has mentioned processing time as a benefit yet. A smaller image file size means more photos can be processed before buffer underrun. I'd be happy with a 16-20MP FF DSLR.

FF is one stop bigger than APS-C so it gethers one more stop of light. This means one stop better noise performance expecting the same sensor technology and processing. (The KP and the Nikon D500 has one stop advantage comparing to other APS-C cameras, so approximetly has the same performance as a current FF camera.)
With the bigger sensor you also lose one stop depth of field. In some situations it's intented in others not. For example the DA* 16-50 and 50-135 F2.8 aps-c zooms are equvivalent to 24-75 and 75-200 F4 zooms on FF regarding DoF and FoV. In the other direction the FF 24-70 and 70-200 F2.8 zooms are equvivalent to 16-45 and 45-200 F2.0 zooms!
If you shoot at the same DoF (not aperture) then you have the same noise performance, so if you want to make the same image you don't get so much. But it extends your possibilities, becase there are combinations which does not have aps-c equvivalent.

There's basically nothing there that's correct. There's no "stop" difference between APS-C and FF. There is a stop difference between 100 and 200 ISO. But if I have my K-1 set to f/5.6 and 100 ISO and it tells me I need a shutter speed of 1/125th, my K-3 will tell me the same thing.

Your DoF statement is also contrary to facts. DoF comes from focal length, not sensor size. APPARENT DoF can be decreased on FF and larger formats due to somethings like image circle size compared to lenses of the same FL in different formcats, ay a 4X5 150mm lens, a 6X7 150mm lens, a 35mm/FF 150mm lens, and an APS-C-designed 150mm lens will all have the same DoF at a given aperture (Allowing for variations in lens formula and flange focal distance which could alter DoF by a few CM one way of the other.)

Shooting at the same DoF is, for all intents and purposes, the same as shooting at the same aperture. Sure my 28mm lens could have a DoF that's ten feet deep, just like my 50mm or 100mm lenses, and would be at a different aperture. And sure accounting for focal length and cropping a 28mm image down to a 100mm frame size would reveal that the DoF is the same, but in practical application and the way that people actually use lenses, that's an argument that doesn't do much outside of a textbook or photo magazine research article.

You also gain some image quality, because at the same MP count a less shar lens needed for the same visual quality. (Bigger pixels accept more blur without overlapping to the neighbour.)

This sounds like it would be the case because LF lenses, for instance, have a lower lp/mm rating than do 120 and 35mm lenses. However, in digital that's no as true. A 24MP image needs to be enlarged 50% more than 36MP image to achieve the same print size. So any lens flaws would be exaggerated by 50% in the enlargement process making them more apparent. Where lower MP counts are beneficial is in diffraction softness, the appearance of which is reduced on lower-MP Cameras compared to same-format cameras with a higher MP rating.

All of that said, that all assumes an totally even playing field for the compared cameras. The sensor is only a PART of the imaging process now. The software and algorithms that support the camera's hardware are about 5X more important to digital imaging than the sensor itself. That's why Pentax and Nikon cameras that use the exact same Sony sensor have different image quality. Instead of worrying about MPs, worry about the support software quality and how well the camera can process the sensor data for the photographer's intended use. The biggest variation between makers is software, not hardware.

[clackers]

I would like to see 1:1 crops taken from a 24 MP APS-C camera and another crop from a 24 MP FF camera each using a similarly rated lens with equivalent FL and aperture. Is the detail in the FF noticeable? negligible?

Probably. I think people would be hard pressed to tell the difference between K-3 and K-1 pics, to be honest. A 5x7 print is going to be downsampled in both cases to just 6Mp or so.

See Biz-Engineer's thread on that, where he compared, IIRC, shots taken with DA300 and 150-450 on the bodies. .

[K David]

A 5x7 print is going to be downsampled in both cases to just 6Mp or so.

Possibly less, even. Assuming that the printer prints at 300 dpi, so 5X7 is 1,500 X 2,100 dpi, or 3.15MP.

[mee]

Probably. I think people would be hard pressed to tell the difference between K-3 and K-1 pics, to be honest. A 5x7 print is going to be downsampled in both cases to just 6Mp or so.

See Biz-Engineer's thread on that, where he compared, IIRC, shots taken with DA300 and 150-450 on the bodies. .

Hmm.. is this the same thing that I'm mentioning? Downsampling sounds more like shrinking the available image yet not going to the full 100% view (1:1). That would be a higher resolution (I think?) than simply taking a 100% view from each image and comparing.. or no? I do that with whole images.. taking the 4920 x 3264 image and 'shrinking' it to say a 1600 px image on the long end.

That is the issue I had with crop (at least at 16 MP) -- the images were never extremely sharp at 1:1... often I'd have to shrink to 50% or so to get a satisfiyingly sharp image.. and with good optics stopped down.

On the K-1 I've noticed I can go all the way to 1:1 crop (zoomed in 100%) and the resultant images are still as sharp as my 50% 'shrunk' aps-c images. It is what got me wondering what is the difference in IQ between 1:1 crops on APS-C and FF. 24 MP seems to be a decent size to compare (with so many APS-C and FF cameras at 24MP).

But really I'm looking for images in a direct comparison.. I'd have done it myself yet I only have a 16 MP crop and a 36 MP FF. So not the same as 24 mp crop vs 24 mp ff. I'll have to do more digging for images it seems.

[clackers]

Hmm.. is this the same thing that I'm mentioning? Downsampling sounds more like shrinking the available image yet not going to the full 100% view (1:1). That would be a higher resolution (I think?) than simply taking a 100% view from each image and comparing.. or no? I do that with whole images.. taking the 4920 x 3264 image and 'shrinking' it to say a 1600 px image on the long end.

That is the issue I had with crop (at least at 16 MP) -- the images were never extremely sharp at 1:1... often I'd have to shrink to 50% or so to get a satisfiyingly sharp image.. and with good optics stopped down.

On the K-1 I've noticed I can go all the way to 1:1 crop (zoomed in 100%) and the resultant images are still as sharp as my 50% 'shrunk' aps-c images. It is what got me wondering what is the difference in IQ between 1:1 crops on APS-C and FF. 24 MP seems to be a decent size to compare (with so many APS-C and FF cameras at 24MP).

But really I'm looking for images in a direct comparison.. I'd have done it myself yet I only have a 16 MP crop and a 36 MP FF. So not the same as 24 mp crop vs 24 mp ff. I'll have to do more digging for images it seems.

You can check out Biz-Engineer's quick and dirty ISO6400 comparison here ...

K-1 vs K3, which is which - PentaxForums.com

[mee]

You can check out Biz-Engineer's quick and dirty ISO6400 comparison here ...

K-1 vs K3, which is which - PentaxForums.com

Yes, I've seen that thread. However, those aren't 1:1 crops. K-1 vs K3, which is which - PentaxForums.com

A 1:1 crop inherently is NOT up or down sampled. This is 1 to 1 pixel mapping of which I'm speaking. In an image viewer, it would be 100% view.

[ffking]

First - i don't now how this stuff works, and don't claim to - but intuitively, logically, higher pixel density (ie APS-C in this case) would have advantages in specific areas where fine detail is what it's all about - combined with greater effective magnification - more pixels per given feature of the subject - macro being the obvious one.

[clackers]

Yes, I've seen that thread. However, those aren't 1:1 crops. K-1 vs K3, which is which - PentaxForums.com

A 1:1 crop inherently is NOT up or down sampled. This is 1 to 1 pixel mapping of which I'm speaking. In an image viewer, it would be 100% view.

Well, the K-3 will get you more resolution, Mee, if that's what you mean.

1:1, there are 50% more pixels crammed into that view.

But, hey, I'm sure you can come up with your own experiments and pics about that.