camera lens changing product color?

You've been at this long enough you should know the answer... it's not the lens silly - it's probably your computer.

I would really suggest you get off that lap top and on to a pc with a larger, perhaps more accurate screen.

I do portraits tethered to my lap top and the colors are always a little different there than on my pc.

Possible, but not likely.

There are several things that can do this:

1. You camera is blowing out one channel, like the reds.

2. Your white balance is off.

3. Your lighting is adding a color cast.

4. You are using some "mode" on the camera that pushes saturation or contrast, or both.