Here is an image from Tutorial 003.

This lesson (continued from Tutorial_003) will show how I interpreted my full color Photoshop pictorial “Crappie Fish Pond” into mezo line art color separations for screen printed T-Shirts. It reveals my experience and trade secrets about the translation from color into black and white line art, and color separations, ready to print.

The previous tutorial explained my creation of this composition

Shades of gray:

Now, after a break and some reflection, the job of translating this full color assignment into a black & white screen print design begins. The techniques revealed here are the result of 30 years of preparing color separated artwork for silk screen. However, rubylith, x-acto knives and opaquing liquid have all been replaced by new digital tools. What an incredible difference! The industry will never look back.

Experience plays a big part in the decisions I’ve made herein. Only practice can teach you what happens when you translate color into black and white, or gray. Practice, practice, practice.

For example, the colors red and green are the same value in a gray image. Their values end up in middle gray. This means that the blue green areas of this painting need to be increased in contrast, mostly lighter, in order to register like the color when translated. You have to imagine how things will look in black and white, knowing this about color. SAVE your files as you work because in the beginning you’ll need to retrace your steps and redo many adjustments before it all works out.

Illustration 19 is the beginning of this solution

In the “background layer,” the water blend, I’ve used the CURVES dialog box to lighten the upper half of the blend, increasing the contrast. As explained, contrast must be enhanced throughout this pictorial before making the conversion to grayscale. The subsequent line art mezotint will look even worse, hence all of this preparation.

Illustrations 20 and 21 show you how I’ve also lightened the two White Crappie in the background, making the upper one even a bit lighter by comparison. It is nearer the light from above. This will mean more when it becomes a mezotint line drawing.

When I have these adjustments where I want them, and it is a guess, I save the file as a temporary archive. If I have to start over this is the file I will return to.

From here we dive into the world of grayscale and black and white line art. The first thing I do is FLATTEN the image and discard any extraneous channels. (EXCEPT the channel that allows me to remove the white background! I’ll need it later when I make the white ink separation. This is important!) These steps reduce the memory size of the file and simplifies the computer processing for all future steps. I then select IMAGE / MODE / GRAYSCALE which converts my pictorial to a gray image. Please see Illustration 22, which also shows how I used the LEVELS dialog box to lighten and adjust the contrast of the image even more. From experience I know that I want a full range of values with some extra darks, as I know that these translate best into mezotint textures and line art. Once I have finished all the adjustments I feel I need, I SAVE this file as a “grayscale master,” which I’ll refer to many times. It also represents again a place to return to if I need to do things over.

At this point I focus on just the black ink separation and its needs. One of the tricks to doing this is to begin thinking in three tones. There will be black ink, white ink and the shirt tone. The black will be darker than the shirt, the white will be lighter than the shirt. So often overlooked, as you plan, you must leave room in the design for the shirt color. I’ve seen many shirt designs that cover the shirt with too much ink, just black and white, and they have a decal or iron-on transfer look, with no delicate sophistication.

(In a different Tutorial I’ll apply this same technique to multicolor separations, which is harder.)

Continuing, the first step is to lighten the lighter values, in some cases even eliminating some of them. Remember, we are distilling the gray image to the portion we want to become black ink only. This takes some trial and error as you’ll see when you start doing it yourself. Then I apply one of my favorite Photoshop Plug-ins, SCREENS manufactured by Andromeda Software. Their web site is: http://www.andromeda.com

This wondrous and often overlooked software is a screen printer’s dream solution and with a little practice it can produce wonderful results for this kind of printing. Illustration 23 shows this plug-in in place in Photoshop, over my grayscale image.

It also shows the actual settings that I used for this procedure. Pay attention to the setting: “Worms Per Inch.” This is the equivalent to setting dot size in a halftone, normally indicated as “lines per inch” settings. In screen printing, when it comes to setting LPI, we work on the low end of resolution. I have also found from experience that making it a little coarser increases the artistic effect of the mezotint. Normal halftone dots in screen printing are about 35 to 45 dots per inch. Here you can see that I’m using 25 “worms” per inch, the equivalent to 25 lines per inch, or dots per inch. Practice has taught me that this produces a really nice shirt illustration that is easier to print. It keeps the detail open on the shirt. Illustrations 24 and 25 provide some studies of the results of this translation. I SAVED this file in both grayscale and bitmap format. It is the bitmap version that I use for screen printing, it is at 200 dpi, more than enough resolution for a silk screen separation.

White ink:

Now we do the same thing, in reverse! Re-OPEN the saved grayscale file (Illustration 26).

IF the image was FLATTENED by any chance, here’s why we saved the alpha channel that clears the background. Your file must be in the same condition as Illustration 26, transparent and with a clear background. The reason for this: We are going to INVERT the image, which reverses the values. If the background were opaque white it would inverse as black, which we do not want. We want no background dots in the background, not even white ones. We’ll FLATTEN it again later just before running the SCREENS filter.

Once again we accent the contrast in the CURVES dialog box, see Illustration 27. Remember, we are leaving “room” in the value spread for the shirt to show through between the black and white inks. So, by manipulating the CURVES we raise the white ink, seen here in black, slightly above the open areas where we want the shirt to show through, creating a full value drawing rather than just black and white. This is subjective but it makes ALL the difference.

Illustration 28 shows the result of my CURVES adjustment. Illustration 29 shows where I even manually used the ERASER tool to 100% remove many of the tones in the bottom of the scene. I don’t want any errant white pixels in the lower portion of the scene. This just an artistic judgement on my part. Illustration 30 is a close up from the White Ink image.

~~~~~~~~

This same procedure is followed for creating the black ink separation, but without reversing the grayscale master image.

As before I SAVE this final file in both grayscale and bitmap versions. We now have two master files that represent the conversion of this image from full color into two separate line drawings that can be reproduced by silk screen printing.

And finally, Illustrations 31 and 32 show how the shirt appears as you first apply the white ink and then the black ink. Of course customized imprints can also be added by the printer. Thank you. Jim Thomas, Digital Designer

GALLERY - Fish Paintings