DOF help!

[neilattopspeedtuning]

I have had my drebel for some time now....about 4 yrs to be exact...

Anyways, i've got the nifty 50, the kit lens and yes even a sigma 75-200 2.8 bazooka lense (lol).

Although the image below is somewhat resized, how can i control shots, so that i get a depth of field similar to the picture below?

Help...thanks.

 

[Socrates]

Use the Sigma set to f/2.8 at 75mm focal length. Adjust the shutter speed appropriately for good exposure. Subject distance "as required."

 

[Big Mike]

Welcome to the forum.

Your DOF is a product of the the aperture of the lens, the focal length and the distance to the subject. Also, the distance to the background will determine how out of focus it can be.

So to get a shallow DOF, you first want to use a large aperture (low F number). So your 50mm F1.8 or the 70-200 F2.8 would be good choices. Use AV mode and set a low F number.

Also, the longer the focal length, the shallower you can make the DOF. Or course, you need to have room to back up and get your subject in the frame.

Lastly is the distance to the subject and the distance to the background. If your subject is close to the background, then it will be close to the focus of your subject...but if you are closer to your subject and the background is farther away, it will be more out of focus.