Trying to get a White Background

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I just bought a Nikon Coolpix 950. I am really happy with the camera. It has a few quirks when it comes to trying to adjust the settings, but other wise it has been a really easy camera to learn to take pictures with. My problem is that I am taking pictures that are to be put in a catalog. However, Photoshop 5.0 and I have not been getting along very well when it comes to silhoutting and clipping paths etc. I would prefer to just take the pictures with a white background so that I don't have to "silhoutte" them or make clipping paths. However, when I take a picture with a white background, the picture never comes out white! I have tried color photos with White Presets, and White balance changes, and B/W photos with Contrast/Lighting/Darkening all adjusted, to no avail. Is there a simple solution to this, or a combination that I have not figured out yet? Is it a photography problem and not a camera problem? Thanks for the input...

-- Shaneen Kohler (shaneen@lyonlvei.com), August 19, 1999

Answers

Whites can be very difficult because of the different types of lighting. Pictures look totally different shoot under fluorescent lights than incandescent. Try using the manual white balance setting. This is where you first calibrate the white balance shooting the white background first to get your white balance (page 7 pocket guide)

-- Ralph (REObert@aol.com), August 19, 1999.

bI'm not sure how much help this will be, but perhaps you can get something useful out of it. What you're trying to achieve by using a white background sounds very similar to the "blue screen" or "green screen" techniques used to film special effects in movies and television. Generally these are used for compositing several scenes or images into a single image or for providing special effects like "flying" against a background or someone or something becoming invisible against a background. What they do is use something called chroma keying and eliminate everything that is a certain color from the signal. For instance, anything that is blue when filmed in the blue screen process "disappears." So if you wanted to make an actor disappear or partly disappear you'd only have to have them fully or partly covered in that color material(like a body stocking) and have them act with props in front of a blue backdrop. Various productions like "The Invisible Man" television series used these types of relatively cheap optical/video effects. This is also what allows "Superman" to fly in the movies. Now, I'm sure by now you'd like me to get to the point and explain how this might help you... :-)

Well, since you probably don't have a Chroma-key feature in your editing program, you'll have to cheat a bit, but it's worth a try. My thoughts are that if you were very careful in lighting your subject to eliminate any visible shadows and placed the subject on a neutral green or blue or whatever color background and took a shot you'd be halfway there with an image devoid of shadows "halo-ing" (?) the subject. The next step would be to set the range of colors so that your editing program's selection tool will select a fairly broad range of similar colors and then use a color picker tool (usually an eye-dropper icon) to select a representative pixel in the background and then use the select tool to select the background and eliminate it. If you've set the range broadly enough and eliminated the shadows with good lighting, then it shouldn't be too difficult to manually clean up the few pixels that the above process might leave in the background with an eraser tool. Voila, you now have an image with a blank background or can invert the selection to grab the object and drop it on the background of your choice. If you invert it and then select it to drop on another background be sure to look for a "feathering" or pixel border selection option under your cut and paste or select tools. This will allow you to set how many pixels at the edge of your image will be blended with the background that you're pasting onto. With the correct settings this will produce very nice product images on the background of your choice.

Don't expect to be wildly successful on your first try and the lighting is a bit tricky to set up, but well worth the trouble especially if you're doing a bunch of similarly sized objects. If the editing process seems complicated it's time to pull out the manuals and read up on the eye dropper, mask or color selection tools and the like. It's well worth the trouble. If I've used the incorrect terminology for any of these tools, my apologies, but different editors seem to give them different names anyhow.

One last piece of advice. Don't try to eliminate all the shaded pixels on the outside border of your objects. They help to blend the image into the new background when you paste.

Good Luck.

-- Gerald Payne (gmp@francorp.francomm.com), August 20, 1999.


White balancing as suggested by a previous adviser is one way. If you don't need precise shadows from the subject on the white background, then using several layers is the easiest approach. Selecting most of the image and copying and pasting it as a new layer in a new file is the quickest. Super accurate selecting is not absolutely necessary. You can erase any over laps quite accurately with a small eraser. Masking is another way. Adobe has a pretty good selection of tips at their site for using Photo Shop 4.0 thru 5.0. They are PDF files (Acrobat). All you need is a free copy of Acrobat Reader.

-- Robert Patterson (rdavid@ix.netcom.com), August 20, 1999.

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