Originally posted by Fogel70 Yes, but what I was referring to was when testing cameras. Then larger sensors will score better at every ISO, unless the camera use old obsolete sensor. Or do you suggest testers start underexpose images one stop when testing noise on FF camera, so the result comply with equivalence to APS-C?
In practical use there might not be much difference as you may have to use higher ISO on larger sensors cameras. Some say 1" sensor is the ultimate sensor size, some say mft, some say APS-C, some say FF.... And they may all be right.
Too, funny, everyone does it so it must be right. Having had academic parents, that kind of argument would have seen me laughed into the next county. That's not proof. That's an admission that you're a victim of herd mentality.
Resist the herd.
What does this have to do with under-exposing? If you understand equivalence, you'd understand under-exposing is not part of the equation.
APS-c- ISO 100, ƒ5.6, 1/50s
36x34- ISO 200, ƒ8, 1/50s
No image is under-exposed, both have the same DoF, the image is made with the same total light, since you have the same signal, you have the same signal to noise. They are functionally the same image with a few caveats.
It's not rocket science.
I can't explain this any simpler.
The big question I would like answered, is why did all those people on all those sites publish all those tables, comparing different images?
The question is why did all those folks you talk about do this?
APS-c ISO 100, ƒ5.6, 1/50s
36x24 ISO 100, ƒ5.6, 1/50s
The 36x24 image uses double the light and therefore has a stronger signal and has better signal to noise...
but it's not the same picture, the DoF is different.
So you want to know why they did this? They are all living in the "36x24 is always better world", and they were looking for proof of their propaganda, not trying to provide useful information. But that was probably just the first guy who proposed the argument (or maybe not even him). The others didn't know enough about what they were talking about and just parroted what the guy they thought was the smart guy said. And there are a lot of people on this site who got sucked in. Many that are still taken in by it.
You could do post graduate work using this as an example of
The funny thing about this is, falconeye, the guys on luminous landscape, everyone who really does understand the physics have always said this was true.
They always said, equivalence didn't mean, one system was better than another. They just didn't waste their time breaking it down so everyone could understand it.
I'm not saying there is not any advantage to 36x24, at the bottom of the spectrum, shooting a lens wide open on both, there is a Narrow DoF, 1 stop better signal to noise image, you can take on a 36x24 camera, you can not duplicate on APS-c. There are bokeh effects in the 35 to 50mm range, you cannot duplicate on APS-c. There are image distortion issues in UWA that may or may not be more pronounced on APS-c. when shooting say 15mm 36x24 and 10mm APS-c. And if you wish to increase your resolution to 36 MP or beyond, you have to go larger format. You do get something for your money. But, it's not as much as many people will tell you. In 90% of the range of possible images, you can take the same image on both systems, there just is not that much difference between them. APS-c and 36x24 are much more the same, than they are different.
And people have said this over and over.
Out of personal preference, there's absolutely nothing wrong with wanting to have that extra 10% for double or triple the price. And a pro may feel obligated to make that extra 10% available to his or her clients, well, because he's pro, but many don't feel any such obligation. Just keep it all in perspective. But don't delude yourself into thinking that by simply going to 36x24 you will make every image better. In fact the opposite is true, If you can take the image with APS-c, odds are, it will be the same, especially for similar costing systems of the same MP.