Spot Colour Separation In Photoshop
Fritzi Vanderweel
I was given a logo by a client and last year I vectorised it, but it was coloured up as per the original, which was fine for her digital printing jobs. This year she wants some merch done, and the printers I am contacting are all asking for the logo to be four spot colours / or three spot colours.
Based on those print requirements, it sounds like you're trying to have your logo screen printed. The printers are asking for this because they want the artwork in a suitable format for the color separation process. To facilitate that, your logo needs to be constructed using exclusively spot colors.
You could regain some of the pumpkin's detail with some fine-tuning and adding in more shadows, or you could even use halftones to simulate gradients. Specifically for a logo though, I think you should just avoid gradients when reducing it to spot colors.
Here is a different spin on @JohnB's separating the original into 4 colors. In Photoshop,I converted the original image from RGB into index mode and forced the design to render as 4 colors only. Next I converted back into RGB mode and created new spot channels from the 4 colors. The spot color separations are not half tones. No color overlaps another color.
By duotone, I am asuming you mean a 2 channel image since the mode is multi-channel. This does not work unless saving as a dcs2 image.Option 1: Convert to duotone and save as an eps file.Option 2: convert to cmyk + spot colours and save as a photoshop pdf. Note: this solution requires the In-Rip separations function ONLY. you cannot output as a separated file.Option 3: save as a dcs2 image. The option only works with separated workflow. You will not be able to output composite high res proofs of this without workarounds.Option 4: save each spot image as a separate file. either bitmap or grayscale depending on the image. Place both into a new InDesign file centered on the page same size as the image. Colourize both to the desired spot colour with the direct select tool. Multiply in transparency the top image to the bottom image. Export as an eps (or pdf with no compression and leave colour as is). Place this new file into your document.John
If it is, then that is the problem. DCS2 images work with a separated workflow. The script the imposes by pdf works in a composite workflow to generate the pdf files.There are other scripts you can use to impose the pages other than the pdf version. My swiss cheese memory is preventing me from recalling the names of the scripts. You can check the studio exchange, I believe one is in there.But, did I mentioned, I hate the dcs2 format. I do all my images as option 4 personally.John
3 CREATE A SECOND DOCUMENT
One of the simplest ways to create a spot color version of a document is to create a second document the same size as the first. To do this, go to File>New and in the New dialog, click the Preset drop-down menu and choose your existing artwork document. Click OK. This will create a new document the same size as your original. To make things easier, go to Window>Arrange>Tile to create a split screen of your two documents.
9 SELECT THE LIGHTER VERSION
Now go back to the main document and select the lighter, reduced opacity version of the first color (in this example, the lighter red color). Again, use any marquee tool to drag-and-drop the selection into the second document, and press-and-hold the Shift key to place the selection in the center of the document.
13 DO A TEST PRINT
You can also do a test print to make sure that each color prints as a separation the way that you expect. Choose File>Print and in the Print dialog, make sure Color Management is selected at the top right. Set Color Handling to Separations. In our example, we chose Landscape for orientation and enabled the Scale to Fit Media checkbox. We also went back up to the Color Management menu and selected Output. In the Printing Marks section, we enabled the Calibration Bars and Registration Marks checkboxes. Now when you print, you should get a separate piece of paper for each of your spot channels.
14 SAVE THE FILE
Before saving your file, check with your screen printing company to see what format they require: they may be happy to get your Photoshop document saved as a standard PSD, or may suggest that you choose Photoshop DCS 2.0 as the format.
SInce I switched to Publisher for all my CMYK work, I thought it might be time to do the same with a project using two spot colors. But I can't find a useful way to work with it.
When using overprint properties Indesign makes it possible to do that per object (line or fill). I think it would be ok, to do it upside down, like the user guide of Publisher is promoting. That would mean to make a copy of a color swatch (one overprintig, one knocking out) and to use these on all objects as one wishes. And it does even work when outputing a PDF. But there is one thing missing - a preview of how my layout actually looks when overprinting, simple WYSIWYG (I'm not even speaking about a separation preview). So that is not very useful.
With CMYK colors it's quite easy - you can just use layer modes (multiply) - see, what you are doing and even get it exported in a controlled way, when using the right PDF export settings. But with spot colors I didn't get any of these exported, they always change to CMYK. I've tried all possible ways (my document is CMYK, FOGRA39 and exporting as X4, X3 or other variants didn't help; of course honour spot colors is on). Any ideas? Has anybody a real workflow for that?
But with spot colors I didn't get any of these exported, they always change to CMYK. I've tried all possible ways (my document is CMYK, FOGRA39 and exporting as X4, X3 or other variants didn't help; of course honour spot colors is on). Any ideas? Has anybody a real workflow for that?
Actually spot overprint do export fine, in various PDF settings (v1.7 with or without profile embedded, or X-4).
Are you sure you created spot colors + overprint? Its swatch shows 3 markers (left, right, top right):
Thanks for looking into that! - But what you show is exactly showing my problem. Maybe I was a bit unclear. In Affinity there is no preview of the result possible. What you see - when designing - is not how it will look at the end (when overprinting - here shown in Acrobat). Exporting spot colors in this case works for me as well. But how could you design without this preview? Imagine even several spot-colored photos on top of each other - hiding one another with their white backgound. Is there a way to preview overprinting live in Affinity?
Because of that problem, I've tried to use layer blend modes (multiply), as I do working in CMYK color space. But this results in converted colors (spot colors show always as CMYK). I couldn't find a way to prevent that.
When using blend modes with spot colors you force Affinity to create colors which are NEITHER the spot colors NOR can't be created of them. Then it becomes relevant whether the blend mode is supported by the PDF format. Not every blend mode is supported in a PDF, this limitation is not related to Affinity but to the technical PDF specification *. Multiply is one of the few supported blend modes in PDF. Whereas for blend modes also the PDF setting gets relevant, too, in particular the PDF version and the Affinity settings in the "More" section: respectively the "Rasterize" and the "Allow Advanced Feature" options. * _2008.pdf
Note in this clip the differing appearance of both various blend modes AND various PDF settings in Affinity "More" options: The 1st/left PDF shows "Rasterize: Unsupported" while the 2nd/right shows "Rasterize: Nothing". The top left group has 'multiply' assigned.
Related to gradients between spot colors, it would be nice to have a duotone/tritone color separation (screening) capability. I used to use a plugin for Corel PhotoPaint years ago for poster and postcard work, and it was pretty marvelous to see full-color images separated out as spot color plates.
Thanks @tomaso for the hint! PDF 1.7 seems to work. I have to check back with the print shop, if they have problems with it. But in my case it looks like a good way to work.
Your explanation, that multiply is allowed in PDF, was also very helpful. Maybe that is a reason, why I have to use multiply directly for images, not for images boxes. But then again it works for groups correctly. Very weired.
Working with spot colors should be more reliable and documented. I know, that most jobs nowadays go online and only have CMYK colors. But it's still an important way to print in many cases.
When an image is brought into Adobe Photoshop, it is usually in a color mode compatible with the device that it was created on. This is often the RGB color mode, which is a common mode for digital cameras and computer monitors. The RGB mode is based on the blending of Red, Green and Blue light. To screen print an image, the colors must be converted to a combination of colors compatible with screen printing. The resulting set of colors is called a Color Separation.
Process color separations use Cyan, Magenta, Yellow, and Black (CMYK) to create the colors in an image. Process color separations can be made by converting a file from the RGB Mode to the CMYK mode using Adobe Photoshop. CMYK inks are transparent and blend on press.
Process color printing usually requires more then just the 4 basic CMYK colors for a quality print. Adding a highlight white helps to control the lighter color ranges. Additional custom colors may also be included for spot color matching or out of gamut colors.
The Simulated Process technique offers the ability to print full color images on light or dark substrates. The inks used with this technique are semi-transparent, providing better coverage. but also blend on press like the Process colors.
ff7609af8f