printing image in black

[Lottie05]

hello I have a 3 color design that I have setup in photoshop, each color has its own layer. I know in order to print the film positive I must convert the design of each layer into black, what is the best way to convert each layer to print black ink only? thank

[Catspit Productions]

I’m no Photoshop expert and I really know Illustrator more. But if each color is already on a different layer and you are printing directly to the printer without RIP then you could select the layer and then use the selection tool for “color same as” or “same color.” It should select all the pixels of the color on the layer you have selected. Then you can change the color to a 100% CMYK black for dense film positives from an inkjet printer.

[Lottie05]

Thanks for your reply. Once I have the images on different layers I selected color overlay and turned the image to black, I repeated this for each color layer.

[upperhandprinting]

It depends on your printer setup, but here's the best way I've found using rip or not and with 3 different printers to get the most opaque films:

Turn off all the layers but 1.
Select the wand tool and turn Contiguous off. Now click anywhere where there is your image on the screen. This will now select all of the info on that layer and nothing else. Now press ctrl+c to copy the information.
now switch from your layers menu to the channels menu.
On the top right of your channels list, there's a menu button. Hit that and a drop down box will appear. Click on "create new spot color channel".
It will pop up asking you to name the channel and select a color. For the color, scroll through the swatches and find Pantone black. (You should only have to do this once, for the following ones it will be the default unless you change it again).
Now press ctrl+v to paste your info on the the channel.
Click to turn off the rgb file so only your channel is showing.
At this point, it might look gray or some other color and not the black you need.
Change your fill color to black.
Then select the information again with the wand. Depending on whether black is your primary or secondary color, press ctrl+delete or alt+delete to fill the selection with black.
To make sure it's correct, pull up your info panel under the view drop down menu. Now with your mouse, hover over a black area. The info panel should read 100% black. Once it does, just file and print your film.
Make sure it's the only channel on when you print.
Once it's printed, turn your rgb channels back on. Turn your newly created channel off and you're right back where you started. Now just repeat the process for your other layers.
It may sound like a lot but once you get the hang of it you can do 6 color seps with trapping and print the films in about 10 minutes or so. Good luck and let me know if you have any other questions.