Hi everyone, I have been using a "Remove white"-PlugIn for my web-graphics for some time. Yesterday I had to prepare some print-graphics and while doing so I noticed that my "Remove white"-PlugIn does not work in CMYK-mode. Turning the picture to RGB, removing the white portions and turning it to CMYK again would damage the colour-settings beyond any hope of repair. So: Does anyone know, if there is a comparable filter that works on CMYK-pictures too? The filter I am using not only removes white, but it also removes white portions in colours, turning them partly transparent, corresponding to their level of whiteness. Thanks, Joerg

Very neat filter. I have the Eliminate White, Eliminate Black and the Whitewash filter. All three of the filters require that your image be in RGB color mode and they will only function on a layer. If your image is on the background, you must first promote it to a layer before running the filter. Eliminate White strips the active layer of white pixels. Light-colored pixels in the layer are made partially transparent based on the level of whiteness. If you find the image too transparent, you can duplicate layer 2-3 times (or however many you need) and merge down (not flatten).

Unfortunately, not all filters work in CMYK mode.

yeah, cmyk is a real bitch with filter programs. Gives ya more reason not to use'em then though. Still, the type of job yer talking about would require a filter program to be used, otherwise way too many hours would have to be put in. Sorry, but my guess is that this message of mine will merely take up bandwith that otherwise could have been spared due to its uselessness.

There are very few filters for CMYK. Most that exist do not work well, and are really not necessary. My suggestion to you is a simple one. Create your separations for the printer, and specify either Pantone or Spot colour inks. Use the correct inks and you'll be fine. Most service bureaus will walk you through the process if you are unsure, and at the same time will help garauntee the final outcome. Proofs can be printed most times for next to nothing.

The problem is, that I cannot choose which kind of colour-format to use. I am just preparing the pictures for my customer. Layout and printing are done by some other bureau and I have no influence whatsoever as to their printing process.

Are your pictures full color graphics, or something that you could do with spot color? You can convert stuff to a duotone in Photoshop and export it as a EPS, in that case the spot color used is actually part of the file. You wouldn't want to do this with a picture that would be normally printed with process (CYMK) inks, though. I've never heard of using white removial on a printed image, to tell the truth, I'd guess this might be something like trapping that is normally done buy the service bureau. CYMK images actually don't contain any white, incidently, subtractive color, remember.

The problem is slightly different: I do not need a whole in my picture. I would use a clipping-Path to do this. All I need is to remove the white portions of several layers to make compositing easier. My customer has a very specific CMYK-colour for his company. If I would convert the picture to RGB, remove the white portions and revert to CMYK, the CMYK-Kombination of colours would change. I just need to remove white areas from some layers. As to the non-existent white: RGB also doesn't know any white colour, but the filter still works. Don't ask me how this is done, but any white area is removed and all semi-white areas are made transparent. For compositing, this is quite a wonderful filter - if you have the commodity of being able to convert to RGB or work in RGB-Mode. I haven't got this commodity and have to work in CMYK-Mode. I just hoped that there was a CMYK-Version of this filter. Would have spared me hours of work on removing the white areas. And concerning the spot-colours: Sorry, I have no say in the printing-process. That's another company and they have decided to use CMYK because the flyer has a lot of photos and this one photo is just one of many photos. I would love to use a Pantone or HKS-Colour, but I can't... But thanks for the help, Joerg

"RGB also doesn't know any white colour, but the filter still works." It's the other way around. CMYK that doesn't know white. The primary (additive, Red - Green - Blue) colors combined create white. The secondary (subtractive, Cyan - Magenta - Yellow) colors combined create black (actually a muddy brown).

Dreamer 101 is correct.If you are printing with CMYK on white paper,then no white ink is used it just leaves the area uncoloured so there is no need to remove the white from the image.If it intrudes over another image,use a clipping path. You could always work in RGB (so that you can use the filters),but keep the CMYK preview mode on,so that you can see how the final image will look even before you convert it to send to the printers. Or how about,working in CMYK then selecting a couple of white areas then using Select-Similar,which will select the remainder of the white areas on the layer and just deleting.

Na, all of that doesn't work. The whole thing is not about the question as to how to select the white areas. It is pretty simple: Sure, white neither exists in RGB nor does it exist in CMYK. While RGB may add up to white, the colour still consists of equal parts of Red, Green and Blue. So, in the end there is no white colour in any colour-system in printing-use. However, when you are working in Photoshop, especially when you are doing image composition, white does exist. It is a colour and I need to remove it or, more exactly, turn every portion of white to transparent. In RGB-mode, the Plug-In works quite well. I would just need a plug-in to do the same in CMYK-Mode: Turn every 100% white point into a 100% transparent point and every point with colour coverage of, let's say 50% into a 50% transparent area. Theoretically white does not exist in CMYK-mode, but reality is a bit different. Try ignoring the white colour in Photoshop and the composite will look somewhat strange as the "non-existant" white simply covers all those areas below it. Select similar works quite differently from the "Remove White" filter. Select similar, if used on a 100% white area with 10% grey bordering that area and set to 10% tolerance would accept the 10% grey, but the 90% grey net to it would not be taken into account. Remove white works differently. When used, it removes any completely white area completely and turns it 100% transparent. a 10% grey area would be turned to 100% black and 90% transparent. a 90% grey area would be turned to 100% black and 10% transparency. This is quite different from what the "Select Similar" does. This filter is not used for printing but only for composition. I am well aware that I need a clipping path to get a transparent area in print. But I just need certain portions of white to be removed for ease of composition. Joerg

maybe you could try using the cmyk channel to select and delete? it would select based on the lightness/darkness of the color and you would be able to delete just the lighter values...I think. haven't really tried it, but it seems like it might work

Corel KnockOut is rather good I hear. Extensis has a filter too: Mask Pro. PS 5.5 and 6 have an extraction that sometimes works nice. I use selection by color a lot. The main problem seems to be the switching to and from RGB. That is possible without messing the color up too much. If you can select this oh so important color you mention in any way you can drag the colors back to their original cmyk settings via a lot of methods. I did some PS work for CocaCola, who always want the same red color, even if it is in photographs, a lot of filters I use require RGB mode but there were always ways to return to the wanted color. Are your cmyk conversion settings, eh, set? I JUST THOUGHT OF A WORKAROUND! Make a duplicate of the photo. Turn it to RGB. Run your filter, store the resulting opacity (option click on the layer) in a mask or an alpha channel, duplicate that to the original cmyk version. Copy the mask to the original layer. Presto! I hope this works (it wil not if the white removal doesnot result in real opacity changes). Good Luck

This is a great idea. It should work out. Thanks a lot. Joerg