AF micro adjustment: adjust all vs. adjust by lens

When using AF micro adjustment, if you have a setting on "All by same amount" and a setting on "Adjust by lens" what is the setting that is used? Does one override the other or do they add together?

For instance, if you have:
All by same amount: +5
Adjust by lens: +8

Is the actual MA value used +5, +8, or +13?

I'm asking specifically about the 5DIII, but I assume MA works the same in other cameras as well.

I have a 50D, and it only allows you to pick one or the other. It's either all or one, so (and this may be me just not being familiar with the 5DII), I don't think you can have both options selected.

It will use whichever setting you have active at the time.

You have to choose one or the other. It will only use the one that you choose.

I don't have my camera in front of me, but I'm sure you can put a value in both settings on the 5D3. Maybe I'm just crazy.

You have the choice of either:

1.) Disable

2.) Adjust by the same amount

3.) Adjust by lens

Which ever one you choose will be used by the camera even if information is entered for each choice.

bacchanal wrote in post #16974666
I don't have my camera in front of me, but I'm sure you can put a value in both settings on the 5D3. Maybe I'm just crazy.

Sure, but it doesn't mean it uses both at the same time.

You need to adjust by lens and leave it at that. The odds of you having multiple lenses off by the same amount is zero.

Gregg.Siam wrote in post #16974747
The odds of you having multiple lenses off by the same amount is zero.

I know. Why would they even have that option?

LV Moose wrote in post #16974775
I know. Why would they even have that option?

Because if they didn't people would complain.

john crossley wrote in post #16974789
Because if they didn't people would complain.

You may have a point.

The camera can be off by a certain amount, just like the lens can. Adjust by all essentially moves the camera's zero point. So, if you're borrowing a lens or shooting with another photog's gear (say, second shooting at a wedding), you're at least at your body's zero point when you put the borrowed lens on. On my 5D3, I use a +5 and that seems to be just about perfect with several lenses.

My question is if I have a lens that needs a little bit more adjustment, what happens if I have adjustments in both settings. Does one override the other or is it cumulative. I can test it when I get home, but I just figured someone would know off the top of their head. It seems the assumption is that the lens setting overrides the adjust all setting.

You must CHOOSE ONE SETTING OR THE OTHER.

If you choose "Adjust by the same amount" the amount that you have filled in will be used.

If you choose "Adjust by lens" the amount filled in for that lens will be used.

YOU CANNOT CHOOSE BOTH AT THE SAME TIME.

LV Moose wrote in post #16974775
I know. Why would they even have that option?

The option is there to adjust the camera if it is off by a certain amount. I think in the real world this is unlikely to be the best bet, but long before MA was available, we used to send our bodies back to Canon to have micro-adjustment done to body which would make the body work better with all lenses. ie: the body could be off front or back focus a certain degree.

ok. Makes sense.

rrblint wrote in post #16974851
You must CHOOSE ONE SETTING OR THE OTHER.

If you choose "Adjust by the same amount" the amount that you have filled in will be used.

If you choose "Adjust by lens" the amount filled in for that lens will be used.

YOU CANNOT CHOOSE BOTH AT THE SAME TIME.

Except you CAN enter values in both settings at the same time. I'm asking for specific clarification on what happens when that is the case. Does Adjust by lens override the all lens setting (or vice versa) or is it cumulative.

I guess I'll just test it myself.