Studio Portraits - Depth of Field Problems

[Ozyboykev]

Hi,

I've just got into studio photography using backdrops, backlighting and continuous front lighting for portraits.

I'm really pleased with the lighting side of things, especially how the 300d copes with colour correction when the white balance is set to tungsten, but I'm jahving a nightmere with depth of field limitations.

I'm using Canon f1.8 85mm and Canon f1.8 50mm prime lenses, both of which are pin sharp, but when using these lenses in these indoor, controlled conditions I seem to be unable to get any decent depth of field. I've tried between f1.8 and f8, but the depth of field returned looks to be about 2-3 inches still.

I can get great results focusing on the medels eyes, but their jewelry, such as necklaces and earlings are still out of focus.

ANY HELP GREATLY APPRECIATED!!




Any advice appreciated

[iwatkins]

To get a good, fully in focus head shot (tip of nose all the way back to ears and hair being in sharp focus) with the 50mm prime I tend to use f11 or even smaller apertures.

Cheers

Ian

[Ozyboykev]

I'll try it this week ... when I'd reach f8 and still couldn't get the earings sharp I thought I must be doing somethiong wrong. I'll continue to step down from f8 and see what it returns, the shutter speed at such small apatures must be very slow though so I guess the medel will have to keep as still as possible?

Thanks for the advice, much appreciated ... Kevin

[Merle]

At f8 you should have 2 to 3 feet of depth of field. Your lens may not be stopping down. Let me ask you when you are shooting at smaller apertures do you need to increase the output of your lights in order to get a properly exposed image? If you are shooting in an automatic or priority mode your camera may be slowing down your shutter speed while you aperture remains at f1.8 ;) :) :D

GOOD SHOOTING TO YA !!
Merle

[robertwgross]

In the studio, one decides which fstop and shutterspeed he wants to work with. Then, he measures and adjusts the output of his light source with the help of a light meter.

If you ask a beginner what the purpose is for aperture settings, he will tell you that it balances against the shutter speed and ISO to get the exposure correct.

If you ask an old pro what the purpose is for aperture settings, he will tell you that it is to control the depth of field.

---Bob Gross---

[robertwgross]

But then, I'm from an age when you worked with whatever film speed you had in the camera ...

Back in 1970, when Ektachrome 64 was king!

I remember my first photo challenge. I was on an overseas military base with a Huey flying overhead. I had to get the shutter to 1/1000th to get close to freezing the main rotor.

---Bob Gross---

[tim]

A 50mm lens at F8, and a subject 2 meters (6 feet) from the camera, the DOF is half a meter. Have a play with this (http://www.dofmaster.com/dofjs.html), it might help.