T-Shirt Forums banner
1 - 1 of 1 Posts

157 Posts
Discussion Starter · #1 ·
If you're a shirt printer, invariably you'll get customers that bring in photographs that weren't necessarily taken in optimal conditions or camera settings. Below is a description of issues you may encounter and some tools you can use to make basic corrections. Note: most of this is applicable to DTG printing.

Condition 1: Color toning looks off. In most scenarios like this, the photo either looks really warm (orange/red-ish) or cool (slightly green/blue-ish). It is the result of improper white balance on the camera or in some cases artificial lighting.

Solutions: Image --> Adjustments --> Photo Filter. These will apply either a warm or cool color toning to re-balance the photograph to natural coloring. You can control the intensity and pick the color it uses to re-balance the photo. The way you can generally tell if the color is in its natural state is if something in the photo that is supposed to be white, actually registers as white (255, 255, 255) or close to it.

Image --> Adjustments --> Color Balance. This is for advanced color toning that can individually customize dark, mid, or light tones. It's pretty self-explanatory, but do not mess with this unless you know what you're doing or if the photo filter fails to produce the effect you want.

Image --> Adjustments --> Channel Mixer. This feature, depending on what your color mode is set to, can allow you to determine what inks (either RGB or CMYK) are used to make up a particular color in your photograph. Although I've never personally used it in this manner, techincally you could make your picture devoid of one of your 3 or 4 ink colors or vice versa by enhancing one of them. In other words, you can make your cyan more cyan, yellow, magenta, or black or less of the four.

Image --> Adjustments --> Replace Color. If you notice that a picture has too much toning of a particular color, you could take a different approach by simply using the eyedropper tool within this feature, selecting said color and desaturate, modify the hue, or change its alpha levels. Those type of adjustments can also be applied to the image as a whole but this particular method allows for more precision.

Image à Adjustments à Variations. This is basically another version of the color balance & channel mixer tool that runs off preset adjustments built into the program for adding more of an ink color to shadows, midtones, and highlights. It’s arguably easier to use and has a neat graphical interface, although I personally prefer the pinpoint control from other tools.

Condition 2: Lighting is under/overexposed. This is something that is usually corrected in any photo that was not taken by a professional photographer. Most people own $200-$300 point-and-shoot cameras with auto iris/shutter controls that are only so good. There are several things you can do to effectively correct for low or bright lighting in a picture:

Solutions: Image à Adjustments à Brightness / Contrast. Pretty self-explanatory what this is. The only thing you may not be aware of is what “Use Legacy” means. It’s basically an older version of the adjustment that shifts the alpha values of all pixels up or down. I don’t recommend using this as it tends to overemphasize midtones and produce a poorly contrasted effect.

Image à Adjustments à Levels. This is accurate control of shadows, midtones, and highlights. A properly balanced image will have as close to a bell curve in the graphical readout as possible. You want to drag the sliders to their respective edges of the readout. Going beyond that with either the shadow or highlight slider will begin to darken or lighten midtones beyond what you may intend. The midtone slider is useful for producing a more evenly lit image. Trial and error is required here more than anything.

Image à Adjustments à Curves. This is basically another way to manipulate the alpha levels of you image, similar to that of Levels. For practical purposes, they accomplish the same thing, but what may be useful to you DTG printers is that if you display the “Curve Display Options” and then select the “Pigment/Ink%”, you can then get a rough idea of how much ink will be used to produce any color you select with the eyedropper tool. I know from experience that sometimes light colors that are close to white may not display as boldly as intended even though they look okay on the screen. Lighter colors will dial in at progressively closer to 0% with 0% being completely white, which would not print at all on a CMYK printer. Darker colors obviously dial in at progressively closer to 100%, which would be solid black. If your image colors consistently measure at or above 75%, you can count on using a high volume of ink in your prints.

Image à Adjustments à Shadow/Highlights. For practical purposes, this is a very smart midtone adjustment tool that I strongly recommend for balancing lighting in most poorly shot photographs. By adjusting the settings on the shadows and highlights, it will bring out detail that is partially or mostly under/overexposed. It will not bring out detail that is totally under/overexposed however. I usually use this tool in conjunction with levels to fix most lighting problems.

Condition 3: You need to convert color gradients into solid colors for other printing applications. You screen/vinyl printers oughta know that Photoshop has some interesting tools that can help you with this.

Solutions: Image à Adjustments à Posterize. For practical purposes, this can convert a photograph into a solid color image which can then more easily be modified for vectorization or other purposes.

Filter à Filter Gallery à Artistic à Cutout. This filter will also convert your image into solid colors while still preserving image detail. The number of colors it creates from a photograph can be controlled with the “Number of Levels” adjustment as well as the “Edge Simplicity”.

Filter à Filter Gallery à Sketch. While options in this category produce black and white images, the two I’d call your attention to for potential raster to vector conversion are “Photocopy” and “Stamp”. These tend to preserve edge detail while producing an image that can be easily be vectorized.
1 - 1 of 1 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.