what is the deal with the 50mm 1.4 ap lens?

Question

i just did my first shoot with it and it was TRICKY! it kept focusing on ONE thing and everything else was blurry and so many times it was the wrong thing. i can see where it can be used to the photographer's advantage but it kept screwing things up. should i only use it for baby shoots? does any one know any tips? thanks!

Answer 1

You're having an auto-focus problem. Take the focus switch to manual (should be on the front of the camera near the side of the lens), or change the place inside the viewfinder where the focus is selected. You don't say what kind of camera you have, but most have at lease 3-5 selection points that you can change. You should see one of them blink or glow when you press the shutter button half-way down and look through the view finder. You can also use the spot to focus on the thing you want to be sharp by pressing the button half-way, hold it down while you move the camera to change the framing/composition, and then take the picture. It will stay focused on the distance you started with.

Remember that your camera will always show you the widest opening depth of field while you're looking through the view finder, then stop down to the actual f-stop when you press the shutter. It does this because otherwise the viewfinder would be too dark for you to see to focus at the smaller apertures. So unless you're shooting at f1.8, you'll be getting more depth of field than you see through the viewfinder.

Answer 2

I use a 50mm 1.8 for portraits. I only open it up to that full aperature if I seriously want to blur the background. I've not had any problems with depth of field of the subject but I am usually several feet away. If depth of field is an issue then see if you can stop the lens down several stops.

Answer 3

Just focus manually. If you don't like all the blurriness, use an aperture smaller than 1.4, like 5.6 or 8 or so...