Line screen question

I’m searching for a capability that seems to have disappeared from the face of the Earth — or I have forgotten what it is called. I want to convert a continuous tone image to a “halftone” consisting of lines in one direction that vary in width to achieve the effect of a halftone without using halftone dots. It used to be called a line screen, as compared to a halftone screen, and it used to be fairly commonly used in illustrations. Can anyone help me find a source? One machine that created newspaper “halftones” using this style of image was the PhotoLathe. But a ruled unidirectional screen was available for achieving the effect in the darkroom. The capability should be possible for computer-generated halftones, but I can’t find it. Help?


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If you get your plates from Owosso, and specify it, they’ll to that for you, or at least they used to.

Hello Bob;

This is still possible to do in photoshop, as well, if you’re in possession of it and so inclined; Photoshop has a “bitmap” section with various options- included amongst those options is “halftone screen”. This is the section with halftone tools in it.
~You can specify the resolution first- for example, a 600 ppi resolution is pretty coarse actually, but is a modest start and if your computer doesn’t have much processing power then this will be a good preview mode-
~and then in this dialogue box, you specify the type of halftone- dots, lines, custom shapes, etc, but you want line-

Hit Okay, and it opens a consecutive dialogue box:

~you assign the frequency (in this case, it really means LPI; whereas the previous resolution value describes the FIDELITY of the rendering- keep this in mind, because even if you make a 2 LPI rendering of a file, and then make the resolution 72, you’ll end up with a coarse file that has lots of pixels.)

~and the angle of the line-screen, which affects the aesthetic and the printed qualities as well.

As Mike said, if you’re not in possession of photoshop you can spec it to a photo-engraver who is gonna make your plates for you, and even boxcar might be able to help you if you use polymer to do it for example. It takes a moment to do.

Best of luck,

I have PhotoShop CS3, and the Image/Mode dropdown has Bitmap greyed out and I can’t figure out how to invoke it. Maybe it’s just there to tantalize the user. I tried with a regular .jpg photo as well as one I had modified a little, and one I converted to a .bmp. Any suggestions? I was sure that capability must exist, but because I wasn’t using the current jargon for it I couldn’t find it in a search on Google.


I am not at my computer with Photoshop but I think it has to be greyscale to activate the filter. Some filters will not apply when it is a BMP/bitmap.

Yes - if your image is in color, you have to make it grayscale first, and then it will let you go from grayscale to bitmap. I always get caught by that, too…

Bob, Yes indeed, they are correct- in CS3 you need to first convert the image to a grayscale image.

Following this, bitmap will become available and you can begin to test settings per your resolution/frequency/angle specs, and just tweak until you are happy. Even changing the angle a few degrees can sometimes make an image work a lot better, for example, or modifying the frequency VS resolution to optimize with one another will create less/more “sawtoothing”- you have to find the optimal settings for each image and take into account the final output device to be used as well, but the answers are out there.

Thanks, all! I did figure out that I had to go to grayscale first, which I did. I then found that the “line” option for it gives the same sort of pattern as the others — basically square dots with highlights and light shadows in the shape of crosses. I tried all the options and never came close to the effect I want.

I’m looking for a way to simulate the appearance of the parallel lines of engraved shading in a wood engraving, with variation in the thickness of the lines to achieve variation in the tone. I don’t want dots or crosses or other “halftone” effects. I suspect that idea was not programmed into any modern image manipulation program, since the programmers weren’t born yet when the effect was widely used. :-)


I can help you out through e-mail, Bob. If you want send me the image and I’ll e-mail it back as you want it :)

Thanks, Enrique, but what I want to do is more complex. I had in mind making maybe 4 or 5 layers of an image, then segmenting them to have part of the image on each, then make a “line screen” conversion of each layer with the screen at a different angle for each, then flatten the image, hopefully ending with an image that looks at least somewhat like a wood engraving. I was hoping to practice the technique while I am waiting for the final image I want to convert, which I don’t yet have. It would be a lot of work, but I am interested to see if I can get the effect I am thinking of. Kind of nutty!


What are the current dimensions and resolution of the picture you’re using? I’ve got CS3 as well and the linescreen setting in Bitmap works exactly as you seem to be looking for for me, but only on high-enough resolution documents. If what you’re starting with is too low resolution, the lines tend to muddy into each other and look like nothing much. If possible, I’d say start with a minimum of 600 DPI at your finished dimensions. You could also try pixel doubling (set the bitmap to 600 DPI from a 300 DPI original), but this sometimes makes things go wonky.

Another possibility would be to try playing with the graphic pen plugin in the filters gallery. It may get you closer to what you’re looking for.

Michael Hurley
Titivilus Press
Memphis, TN

Bob, I can help you with that. I’ve done exactly that before with the image of a bear, selecting different areas in layers and making them look like a wood engraving, since I love that effect, I’ve tried to reproduce it as close as I can.
I’ve done it with photoshop, and also with an Illustrator Plugin called Phantasm CS Studio, that actually has a preset for wood engraving simulation. It’s not all automatic, but if you know what you want it to look like it’s very useful.

Hi Bob-never found Photoshop half tones much good, having been brought up in wet film proceses with screens, a better option was a plug in to Photoshop called Andromeda Screens, it is not too expensive, also they had a special effects button/selection to convert one thing into looking like another-recommend it, check it out.
also Polycrom used to make “screen tints”…..might be possible to scan these into your computer photoshop to create your own half tones filters that you use as a layer over your continuous tone image to maybe create the effect/illusion of a half toned image. You can create your own half tone screens eg scanning in mesh etc save these in custom in bitmap half tone to apply to other images. Best.

I used the Andromea Photoshop filters too, back in OS 8, which gave straight-line screens as well as radial line and mezzotints.
Don’t confuse contact screens (used on camera) with screen tints (used in contact frame). A contact screen allows different values because the edges are vignetted—that is, diffuse, so the film can be exposed to different areas of light and dark. A contact screen has hard edges of a specific value, can’t pass a 75% image value though a 25% contact screen.