Interesting read.

http://www.luminous-landscape.com/essays/an_open_letter_to_the_major_camera_manufacturers.shtml

Interesting. I almost thought I was in PaRD and was about to laugh at the damn Zeitgeist theories, but this may actually be true.

So my 50D is underexposing my image by .62 stops when shooting at f/1.4?

Aka instead of ISO 100, it's ISO160? Similarly speaking... instead of ISO3200 it's at ISO5000~?

no as the last graph shows the underexposure level drops at f2 then again at 2.8 and finally at f4 there is no underexposure

I am not sure I have understood:

1) That means that between F1.4 and F4 the old Canon 5D has lower loss of light due to the direction of entering light?

2) We also have to count the T aperture of lenses to calculate the final real aperture?

So it could mean that if I own an old 5D and I have a simple lens I would probably have much more light at the same ISO of a 50D with a 24-70 2.8?

Ty

Correct me if I am wrong but the slight loss of light can be corrected in post-process and shouldn't be that much of an issue especially with the
very good high ISO performance of most modern DSLRs even those with very high pixel density like the EOS 7D.
I believe the difference in DOF at the same aperture on different sizes of sensors is something more important to know.

I think the issue is more to do with camera manufacturers misrepresenting and downright lying to their clients.

That pretty much sums it up. Sorry I didn't get back to this thread here, I've been following it elsewheres.