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bdj3
8th of March 2007 (Thu), 19:10
I am having a problem when I shoot with the 50mm..it tends to make some of the picture oof. is there something I'm not doing? How do I guarantee the whole picture is in focus? example:
http://i75.photobucket.com/albums/i317/bdj3/088.jpg
http://i75.photobucket.com/albums/i317/bdj3/064.jpg

ibdb
8th of March 2007 (Thu), 20:52
If part of the shot is in focus, and another portion at a different distance from the camera is not, then you probably need to shoot with a smaller aperture (f/8, f/11, etc.) to increase your depth of field.

This shot was at f/3.5, which is going to give you a pretty shallow depth of field in many cases. Try searching the forums for "depth of field calculator." There are a variety of them to choose from. With one, you can put in your camera, lens, distance to your subject, and aperture and get a pretty good idea of what range of distances will be in focus for any given composition.

Another possible issue, and one that I don't have any personal experience with (I don't have a nifty 50), is that the nifty 50 has been said to hunt for focus in low light situations, which could also affect your outcome.

ibdb
8th of March 2007 (Thu), 21:21
Found a few more minutes and used Curt's Photography Calculator (http://boonecounty.info/photocalc.htm).

Assuming the subjects are 6 feet away (wild guess and just for an example), a 50mm at f/3.5 would have everything from 5.7 to 6.3 feet in focus -- meaning your total depth of field would be about 6 inches. Anything closer than 5.7 feet, or farther than 6.3 feet will start to be out of focus. Go to f/8, and you have 1.3 feet to work with; f/11 gives you 1.8 feet.

bdj3
9th of March 2007 (Fri), 07:32
thanks so much! big help!