Front/back focus; lens v.s. camera

amoringello · 2008-08-18T16:56:55+0100

I didn't want to hijack other similar threads yet hesitant to start another, but I'm curious as to how the lens can cause front or back focusing? I have adjusted my camera in debug mode and it seems to have solved most of my issues. Now I'm looking to get the 55-300 lens but read about some of them possibly having focusing issues. My confusion comes in how the lens might play a role. As I understand things, the camera is looking for edge contrast to determine where to focus. It makes sense that if the camera is off a bit that the area you're focusing at will not necessarily match precisely with the camera. But if the lens is off, won't the camera still try its best to attain sharp focus on the specified area? The camera may have to go further forward or backward than with another otherwise identical lens, but still the same spot has only one point at which the edge contrast will be 'correct'. Does my question make sense? What am I missing? Since the K20D has several auto focus adjustment slots, I would assume there is actually a need but I cannot think of how the lens would make much difference.

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johnriley johnriley

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Posted 21/08/2008 - 22:17 Link

Quote:
but they will accept mastercard if I send them a pic of my card front and back Not sure I would want to do that though.

If you do that you will have given them a bit more information than usual. I'm not sure how significant that would be but I personally would not do it.

Can you place a web order instead?

Best regards, John