# Digital photos -- CMYK vs RBG **URL:** \ **Category:** Factual Questions\ **Created:** [December 15, 2007, 7:01pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122 "2007-12-15T19:01:47Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Clark\_K](https://avatars.discourse-cdn.com/v4/letter/c/c77e96/32.png) [@Clark\_K](https://boards.straightdope.com/u/Clark_K)\ **Post date:** [December 15, 2007, 7:01pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/1 "2007-12-15T19:01:47Z")
Help! I’m trying to put together a photo album as a Christmas present. I’m doing it through My Publisher, where you upload photos, arrange them in an album and they print it up for you. But apparently some of my digital images are in the CMYK color format and My Publisher accepts only RBG. Not exactly sure what that means, but that’s what they say. Does anyone know if I can convert the photos to RBG so I can use them? How do I do it? Thanks, Clark ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [December 15, 2007, 7:15pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/2 "2007-12-15T19:15:42Z")
Almost any decent image editor will do it. Photoshop, for example. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [December 15, 2007, 7:16pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/3 "2007-12-15T19:16:15Z")
Yes, you’ll need to convert them. Many decent image-editing programs can do that; Photoshop can do it blindfolded with one hand tied behind its back. CMYK is the colour setup for four-colour printing: Cyan, Magenta, Yellow, blacK. (Black is K so it isn’t confused with blue. Among other reasons.) RGB is the colour setup for computer monitors: Red, Green, Blue. Look closely at your monitor and you’ll see the red, green, and blue dots. When a program displays a CMYK image on a computer screen, it does a rough internal conversion so that it can display it. Real high-quality color conversion involves internal models of specific inks and whatnot so that the system can accurately make the change. One reason Photoshop is so expensive is that Adobe licensed CMYK colour information from places like Pantone and Dai Nippon Inks, who charge big bucks for it. Photoshop’s CMYK print functions also have adjustments for things like the way the ink spreads in the paper when it is applied by the printing press (“dot gain”). I just checked my copy of The Gimp (the freeware image editor); it does NOT handle CMYK. ☹ ---
**Author:** ![Clark\_K](https://avatars.discourse-cdn.com/v4/letter/c/c77e96/32.png) [@Clark\_K](https://boards.straightdope.com/u/Clark_K)\ **Post date:** [December 15, 2007, 7:21pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/4 "2007-12-15T19:21:16Z")
Thanks. I don’t have Photoshop. I simply have a CD full of old pictures that have been scanned in. It looks like I can choose open the image with Microsoft Picture Manager, Windows Picture and Fax Viewer, or Paint. Anything in those options that will help me? ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [December 15, 2007, 7:23pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/5 "2007-12-15T19:23:33Z")
Here’s a page [from a print shop](http://www.printingforless.com/rgb-cmyk.html) that discusses conversion between RGB and CMYK. Of course, they’re printing, so they’re going the other way: _to_ CMYK. I looked at the My Publisher site, and it looks like they want everything in RGB, and then they do their own conversion. (If they’re printing, they probably use CMYK at the end of the process.) ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [December 15, 2007, 7:29pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/6 "2007-12-15T19:29:05Z")
I just did a search on CMYK to RGB freeware converters; possibly [this program](http://www.fileheap.com/software-free-image-editor-download-17055.html) can do it. I’m on a Mac, so I don’t have Windows programs at hand at the moment. ---
**Author:** ![Szlater](https://avatars.discourse-cdn.com/v4/letter/s/90ced4/32.png) [@Szlater](https://boards.straightdope.com/u/Szlater)\ **Post date:** [December 15, 2007, 7:32pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/7 "2007-12-15T19:32:39Z")
Download the free trial of [Photoshop](http://www.adobe.com/products/photoshop/photoshop/) and do the conversions… you’ll have 30 days in which to use it. ---
**Author:** ![Clark\_K](https://avatars.discourse-cdn.com/v4/letter/c/c77e96/32.png) [@Clark\_K](https://boards.straightdope.com/u/Clark_K)\ **Post date:** [December 15, 2007, 7:35pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/8 "2007-12-15T19:35:10Z")
Thanks so much for the suggestions. I’ll give them a try. ---
**Author:** ![Clark\_K](https://avatars.discourse-cdn.com/v4/letter/c/c77e96/32.png) [@Clark\_K](https://boards.straightdope.com/u/Clark_K)\ **Post date:** [December 15, 2007, 10:14pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/9 "2007-12-15T22:14:27Z")
I tried dowloading PhotoShop, but that would have taken about four hours. I did download a free-ware program, but I couldn’t figure out how to get it to do what I wanted. In the end, I found that if I opened the photos in Microsoft Picture Manager, hit auto adjust and then saved them, Bookmaker would then accept the images. So it all worked out. Thanks for all the quick assistance. ---
**Author:** ![Nanoda](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Nanoda](https://boards.straightdope.com/u/Nanoda)\ **Post date:** [December 15, 2007, 11:26pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/10 "2007-12-15T23:26:54Z")
I guess it’s already done, but I’d have used the [imagemagick](http://www.imagemagick.org) library, as it’s installed on my server and [appears](http://www.imagemagick.org/script/formats.php) to be able to handle CMYK conversion. There are binaries available for Windows and Mac if you don’t have access to a Linux box. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [December 15, 2007, 11:32pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/11 "2007-12-15T23:32:55Z")
I was hoping **cmyk** would jump into this thread. Maybe he or she didn’t want to be converted… ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [December 15, 2007, 11:37pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/12 "2007-12-15T23:37:41Z")
[QUOTE=Nanoda] I guess it’s already done, but I’d have used the [imagemagick](http://www.imagemagick.org) library, as it’s installed on my server and [appears](http://www.imagemagick.org/script/formats.php) to be able to handle CMYK conversion. There are binaries available for Windows and Mac if you don’t have access to a Linux box. [/QUOTE] That looks interesting. There are times I’d like to automate operations on images. I’m running a Unix box (Mac OS X 10.5), so it may even be useful from the Mac OS X Automator! ---
**Author:** ![jjimm](https://avatars.discourse-cdn.com/v4/letter/j/ba8739/32.png) [@jjimm](https://boards.straightdope.com/u/jjimm)\ **Post date:** [December 15, 2007, 11:42pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/13 "2007-12-15T23:42:07Z")
Download [Picasa](http://picasa.google.com/) from Google. If you choose “export” on any given picture (and you can tweak them beforehand too, e.g. cropping, color enhancement), you will have an RGB jpeg. It’s an excellent organiser, display, and photomanipulation program, and it’s free. ---
**Author:** ![Nanoda](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Nanoda](https://boards.straightdope.com/u/Nanoda)\ **Post date:** [December 16, 2007, 12:50am UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/14 "2007-12-16T00:50:56Z")
[QUOTE=Sunspace] That looks interesting. There are times I’d like to automate operations on images. I’m running a Unix box (Mac OS X 10.5), so it may even be useful from the Mac OS X Automator! [/QUOTE] Indeed, that’s the usual thing it’s meant for. I’m typically [convert](http://www.imagemagick.org/script/convert.php)ing a single tiff to png or something, but it’s also the back-end for the [Gallery](http://gallery.menalto.com/) web-based photo album’s image resizing/rotation/etc., so it’s quite flexible. ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [December 17, 2007, 6:33pm UTC](https://boards.straightdope.com/t/digital-photos-cmyk-vs-rbg/430122/15 "2007-12-17T18:33:45Z")
[QUOTE=Sunspace] I was hoping **cmyk** would jump into this thread. Maybe he or she didn’t want to be converted… [/QUOTE] UGH! I’ve waited SEVEN YEARS for this thread, and I missed it! _cancels membership_ (I’m a he, btw)