How does a SLR show a very uniform white background without green?

First of all, you should know that your target photo has a good light, there must be light, and it comes from the photographer's right rear. Secondly, your white balance setting must be automatic. When you are under an incandescent lamp or in the sun (the light is not very strong), take a blank sheet of paper, then look at the white balance value in the photo information and record it. Select a custom white balance in the camera, enter that value XXXX K, and then shoot with this.

Finally, use a tripod when shooting, be steady, focus is not accurate, not on the clothes, the clothes are empty, of course, there is no texture. Don't focus automatically, choose focus manually, and focus with live view is better.