View Single Post
Old Oct 4, 2005, 7:31 PM   #14
JimC
Administrator
 
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,378
Default

1958fury wrote:
Quote:
Thanks for the reply Jim C. If that's the case, my 7D "back-focuses" alot!!
Not necessarily. It could be that you're missing your subject, or you think it's backfocusing because the lens is sharper in one area compared to another.

But, if you notice some backfocusing in a consistent way, it's a good idea to check it out using a tripod and test targets (so you can see if it's focusing on your subject, or in front or behind it). I'd probably make sure to try more than one lens on it, too.

It's my understanding based on user reports of phone correspondencewith KM, that theyuse a 50mm f/1.7 to calibrate them, using some pretty sophisticated techniques (patterns generated that each AF sensor picks up, with software "talking" to the camera showing a numerical indication of where the adjustments are correct for each screw,so that they know when they've got it "just right").

You mayjust want to send it in to KM with a note that you think it's backfocusing, and let them calibrate it. Even though I'm mentioning a way that some users have found to do it themselves, the better way to approach it would be to let KM do it. For one thing, they're probably very good at it by now, and theyhave the expertise and equpment to do it very accurately.

Also, you wouldn't need to worry about any potential warranty problems, should they decide that you're abusing your equipment in some manner by doing it yourself (and there is always a possibility that you'd damage it in some manner, too).

Personally, I'd probably do it myself. But, then again, I do the same thing with a little Konica pocket camera I've got. I've used hidden service menus to change things, including AF calibration with it. ;-)


JimC is offline   Reply With Quote