[Samsung Galaxy S23 Ultra] ajarosz:
Ok. That is bizarre. Why do we have so different behavior? I would like to understand that, so maybe it will be more clear how to get better results on both.

If you are willing to, we can have some more comparisons, and do a small investigation. Maybe it will help us both to have better results from out S23U. :)

After work I will try to make some more comparisons, with some different structures and patterns, to check maybe if you can predict when that is going on with that noise reduction in ExpertRAW. That first thing.

The Second is - the resolution of outputs. Let's clear out the way one thing - the theoretical resolution of the image. We can use this calculator to have very raw assumptions about the diffraction limits.

Diffraction Limited Photography: Pixel Size, Aperture and Airy Disks

www.cambridgeincolour.com

From the bottom one, you can choose parameters close to what S23U has as a main sensor, and the diffraction limit will be about 70 Mpix. You cannot choose exact ones, so let's say 80 Mpix. But on the same page, you can read:

and:

also:

finally:

Having that in mind we can apply some of the numbers in our calculations. 80 Mpix / 1.2 (dependency from lightwave length) / 1.05 (very optimistic approach about pixels usage vs sensor size). That gives us a theoretical resolution of about 63 Mpix. Not taking into account micro gaps between pixels, and the material of lenses used in optics. The last one dramatically reduces resolution, as each lens used in the optics will lower it a bit. There is no single lens in photography word, that will give an image close to theoretical resolution from the diffraction limit. It is hard to calculate it, but it will give us much less, than 50 Mpix. I would be happy if the real possible resolution would be around 30, and it is far from being even that I would say. Side by side, when taking pictures from my A7 III, details are better on the A7 III, which has a 24 Mpix sensor. So, therefore, even if the output image resolution of the Samsung S23 is greater, the detail resolution is lower. And that is the reason why is it easier for me to sacrifice 50Mpix from ExpertRAW. From my experience, the difference in Samsung apps 12 vs 50 Mpix is not because 50 Mpix is that good, but rather 12 Mpix is that bad in resolving details.

Then we have GCAM and ExpertRAW resolution. As ExpertRAW can use full readout from the sensor, it has theoretically better input and therefore does not have to upscale images. Output depends on many things, like how the signal is being demosaicked, how Samsung is postprocessing it, etc. But anyways, having in comparison 50 Mpix from ExpertRAW is ok. On the other hand, there is GCAM. On the input, it has only 12 Mpix pictures. Samsung is not allowing 3rd party apps to use full API from the camera. So that resolution, only that will be native, and give the best results. Anything above will be upscaling, which can cause artifacts, as the algorithm will try to guess details.

Then, as for your comparison of yours, I have never seen GCAM behave that badly in comparison with a stock app, or ExpertRAW. What version with which configuration do you use? Maybe something is off with it? You don't have to answer that question, but from what market is your S23U? Maybe there is a difference with some of the components (which Samsung is not bragging about and not as easy to discover as it was with CPUs in the last generation) and that can explain why there is different behavior in the ExpertRAW...

Again, no trying to pick which one is better, not trying to convert anyone to anything, just trying to understand differences in behavior that we have in camera, as it can only be beneficial to all people using S23U.