All color copy machines are digital and work much like a computer scanner connected to a laser printer. The copier scans the original then transfers the information via laser to a charged image drum. Color toner adheres to the charged areas of the drum before being transferred to paper. The final step, as with a laser printer, is to heat the toner on the page and fuse a permanent image.

High-end models apply all four colors in a single application. Low-end machines take four passes of the same image, rolling the paper around the drum four times to apply each color. While low-end technology is less expensive, it also makes for slower copying speeds. Be careful to compare different color copier models before making a purchase.

Color copy machine editing features
Standard features on digital color copiers include border erasing, image centering, color adjustment, and color balancing. Some models offer a whole menu of additional editing functions, such as colorizing, which lets you create color documents from black and white originals.

Although these advanced editing techniques can be impressive, they tend to be difficult and time-consuming to master. And, if your copier is set up as a network printer, you can do much more complex image manipulations using standard image editing software at your computer, then simply print the results. Basic editing functions are enough for most users.

If you do choose to invest in an editor, or a model that includes one, and set out to compare features across models, you may find the process frustrating. Most of these editing features are named differently from model to model, even though their functions may be the same. Ask a sales representative to demonstrate exactly how to use the editing features you want.

Consumables
You should also factor consumables, which will need to be replaced periodically, into the overall purchase of a color copy machine. The major consumables color copiers require are paper, toner, developer, and fuser oil.

• Paper costs will be a significant part of your overall copying costs. You should select the paper for your color prints carefully, since it will probably be more expensive than the paper you buy for regular copying. Color copier manufacturers typically recommend that you use brighter and heavier paper with a color copier.


• Dealing with toner is more complex with a color copier than with a black and white copier, since four complementary toner colors are used: cyan, magenta, yellow, and black. (These are referred to as CMYK, where K stands for black.) Each toner color typically comes in a separate bottle or cartridge, so you can replace colors as they run out.


• Toner needs to be mixed with developer to be magnetically attracted to the copier drum and then fused on to paper. Most copiers require a separate developer for each toner color. Developer usually has a yield that is twice that of the toner. TIP: When copies seem to get lighter, it is usually time to change the developer. When you run out of toner, on the other hand, you will see an overall unevenness in color.


• Fuser oil is required for the last step in the (laser) copying process and does not need to be replaced often. One bottle will generally last twice as long as a bottle of developer.