I was just checking AF corrections outdoors in the late afternoon on my 500 f4 VR and old 80-400 f5.6 VR with both D300 and D800 bodies.
Both these bodies have solid SLR prisms but obviously the D300 is DX and D800 is FX format.
Notwithstanding the difference in field of view and viewfinder size, I noticed that the D300 viewfinder was much brighter in the fading light than the D800. This difference was common with both lenses.
Although not as sharp, vf display on D300 with 80-400 f5.6 was brighter than the 500 f4 on D800 and even brighter when the 500 f4 was fitted on the D300.
I would have expected the opposite. Any explanations?
Hi James, Just for clarity, when you say viewfinder, I assume you're talking about the LCD on the back of the cameras. If so, could you have the LCD brightness adjusted differently for the two cameras? That setting is in the Setup Menu, second setting - it's directly under the setting for formatting the memory cards. Best regards, Tom
"Nothing can be recognized without light and shade. It is only through the eye, the window of the soul, that we can truly understand the complex workings of nature." - Leonardo da Vinci
Interesting observation James. I duplicated your results and find the D300, D200 and D2X/H viewfinders are brighter than the D3, D700 and D800. Since the sensors and prisms are smaller on the DX bodies than the FX bodies there are only a couple things that can account for the difference. That would be pentaprism transmission loss, focusing screen brightness and the percentage of light going to the AF sensor. Maybe only Nikon can tell us what causes the loss. But I went a little further and checked the brightness of the most current film camera I have without auto focus, the F3 with HP finder. It appeared to be brighter than the D300. I don't know what that means but that's what I found.
I was able to make some meter measurements through the viewfinder using the spot meter attachment on a Gossen Luna Pro. I found the DX bodies were 1 EV brighter than the D800 and D3 and the F3 HP was 1.5 EV brighter. I had a 300mm f4.5 lens mounted on a tripod focused on a fixed target and just kept switching camera bodies..
There are significant differences in how the autofocus and metering systems pass light through the mirrors on those cameras. It seems to me that the later cameras "steal" more light to feed those more advanced functions.
Sun 30-Jun-13 11:04 PM | edited Sun 30-Jun-13 11:08 PM by ajdooley
Just a random thought here -- and probably completely unscientific -- but could it also be a matter of the same amount of light spread over a larger area? (The FX vs. DX screen) Ignore me is this makes no sense.
As for the F3HP brightness, remember -- no autofocus? Didn't the metering work by measuring the light through some almost microscopic slits in the mirror? No light was "stolen" for AF.