Shooting products a home made light tent

[srekdal]

I've built a light tent (a box frame made out of white plastic tubing, white sheets to make the walls of the box and a series of lights outside the box that are diffused by the sheets).

I'm shooting with the standard lens that comes with the D70s outfit 18-70mm

set on f4 with about an 80 shutter speed, using the timer on a tripod.

ISO is set for 200

Here's the problem. The pictures have not been sharp, and also if the pictures are sharp, they are only sharp in the center. I'd like to avoid the depth of field effect and get the entire image in focus.

What am I doing wrong?

Thanks in advance!

Scott

[sirhc55]

Scott - when I shoot product in a cocoon (light tent) I usually shoot anywhere between f/11 and f/22 to get the DOF. My wine bottle shots are all shot at f/16. I also bracket all shots for exposure comp. Hope this helps

[MATT]

edit.....( you have to be quick around here )


What CHRIS said..


MATT

[gstark]

YEp, What Chris said.

At f4 you will have very little Depth of Field, and the situation you're describing is exactly this problem.

How good (solid) is your tripod? Can you lengthen your shutter speed and set your aperture to correspondingly higher value?

Can you increase the light intensity, or perhaps move the light sources close to the light tent?

[srekdal]

Well, my tripod is cheap (really cheap). I can't adjust the light intensity too much.

I shot it in the light tent under a skylight. When the sun came in the skylight and lit the tent significantly more than the other lights I still had the same problem.

Is there a way to get the entire shot in focus? Your wine botthe is a good example. If I were shooting slightly down on a wine bottle, can I get the cork (which is closest to the camera) razor sharp as well as the fine print on the label at the bottom?

Scott
(You guys rock by the way! Thanks for the quick response!)

[stubbsy]

Scott

DOF is very much a function of the aperture size - the smaller the aperture (and the longer the expsoure time) the greater the DOF. Bumping up the light will NOT improve DOF ir will just blow your highlights.

Edit: A link that talks about this in some detail is here and a more technical discussion can be found here

The luminous landscape site in the second link is great for all sorts of other info too.