Diopter adjustment

[Devrij]

I noticed the other day that I was having trouble focusing with my viewfinder and that the image wasn't sharp to my eyes unless I really squinted.

The display all looks pin sharp (that's how I originally set it) but the image isn't unless it's a close object. If I'm focusing on a distant object (10ft or more) then I have to set the diopter 7 clicks from the left for it to look sharp, but then close up objects don't look as sharp when I focus on them.

I assumed that the image I was looking at in the viewfinder was on one 2d plane, so I can't understand why this would be, unless this isn't the case and I'm just a bit short-sighted?

I do spend all day using a pc at work so maybe my eyes are just a bit tired, and it seems less of an issue when it's bright out (viewfinder is a bit dim on my 550d).

Anyone know what I need to do? For now I just have to trust my autofocus.

 

[Devrij]

About a year or two ago. I was thinking along the same lines myself. I think it may be a combo of eye-fatigue and spending so much time in front of a monitor that I'm becoming short-sighted.

The only thing I thought was odd was that the diopter adjustment was a compromise. I thought once it was set correctly everything would look sharp if it was in focus, regardless of whether it was close up or far away. The setting I have now (7 clicks clockwise) seems to be perfect for mid-to long distance, but if I'm doing a macro shot it looks slightly blurry and is much sharper at 0-2 clicks from the left.