Background to white on product shot

[CaptainTom]

I have some eyeglass images that need the background to be pure white, but the product exposure to be normal.....
I haven't had to do this in so long I can't for the life of me figure it out.
Help ?

[dmcantrell]

Put a flash on the (white paper) background that is separately controlled from the one lighting the subject. This should get it close. Push the rest of the background pixels to 255 in Photoshop with a Levels adjustment. At least this is what I would try.

[Redneck]

Set a custom white balance on the camera by using a white/grey card and use this setting for the actual shoot.

[mdh]

One softbox above one third in fount of lens two thirds behind.
exspose for the frames the back ground should be 11/2 to 2 stops over exsposed more will cause unwanted flare on the frame.
Mike

[srwatters]

If you use even lighting on the BG and super white or arctic white paper all you need to do is properly expose the BG. Pushing the exposure 1.5 to 2 stops over the main exposure is asking for a over back lit subject at this close range. Another option is to use a light tent. For an item this small, that's what I'd do. You can even make your own from white rip stop nylon found at any fabric store. Couple that with a frame and three lights and you'll have a nice white surround for the product. Take care to 'ground' the subject unless you want/need that 'floating on air' look.

Have fun!

[CaptainTom]

I screwed up and didn't explain my problem correctly.

I've already done the shoot and need to put it right on Photoshop.....
I'm getting there on my own but thought some help from the gurus would make it faster.

[srwatters]

Emily Litella said it best...

"Oh, that's very different.... Never mind."

[texxter]

Tom, is your background near white and you only need to make it pure white? Or do you have to extract the product from a non-white background?

[CaptainTom]

Originally Posted by texxter

Tom, is your background near white and you only need to make it pure white? Or do you have to extract the product from a non-white background?

I've got it solved.
I'm taking the RAW file, tweaking white balance, adjusting exposure until I get blow out covering the item, opening in PS and just brushing in 255 white in the non 255 areas of the background.
Next time it will be simpler because I'll eliminate any variables.

The hitch is that they wanted a hint of shadow to keep away from too much 'floating in space' feeling.