Custom Setting Menu Question for Nikon DX Bodies

[06Honda]

I do mainly bird photography and would like to know a little more about the setting noted in bold below:

Custom Setting Menu
a Autofocus
b5 Center-weighted area
6mm
8mm
10mm
13mm
Average

Mine is set to 8 mm. This setting is when choosing the size of the area given the most weight in center-weighted metering. Is one setting or selection in the list make any real difference for the photography that I do. Basically is there say a big difference between each of these for the overall outcome of a photo.

 

[Fred Kingston_RIP]

This is from a D7000 manual... but I'm sure the same paragraphs are in each model's manual... note the highlighted last few sentences...

Center-weighted: A blend of matrix and spot metering, this mode bases exposure on the entire frame but puts extra emphasis, or weight, on the center of the frame.
Normally, the area that’s given priority in this mode is about 8mm in diameter. But you can alter the critical metering area through the Center-Weighted Area option, found in the Metering/Exposure section of the Custom Setting menu. You can change the size of the metering circle to 6mm, 10mm, or 13mm. (The menu option is available only when the Mode dial is set to P, S, A, or M.)

• The Center-Weighted Area option also offers an Avg setting, which tells the camera to take a reading of the entire frame and then base exposure on the average brightness values it sees. The difference between this option and the Matrix setting is that Matrix is based on a newer, more capable technology, whereas Avg is based on a system used in earlier Nikon cameras. Longtime Nikon shooters who are familiar with this metering option may appreciate its inclusion on the D7000, but the matrix system typically delivers a better exposure if you're concerned about objects throughout the frame.

 

[desmobob]

I'd guess a lot of (us) "old timers" are used to using the 80/20 center-weighted metering in the center 12% or so of the F2 or F3 viewfinder from the film days. Narrowing down to 8% makes it more towards a spot meter, but the camera is still only using that area's reading for the majority, not all, of the exposure calculation... the other 20% in the calculation comes from the rest of the frame.

My opinion is that if you want to narrow things down that far, I'd just go to "spot" and know that the exposure is going to be based on exactly what is under that spot, not mixed with the other parts of the frame.

I think with my DSLR bodies, I trust the modern Matrix metering 95+% of the time and if I switch away from that, it's to the "spot" setting. I don't know if I've ever taken a DSLR shot with the meter set to center-weighted. But that's just me and I'm no pro....