Colour discrepencies between illustrator and InDesign

Question

Hi!
I am a semi-amateur CS user, and am trying to create branding and a brochure for my own new business I'm starting.
I have drawn a logo in illustrator, which is a single solid colour, as well as some extra branding motifs which are a collection of simple silhouettes in a further 3 solid colours. I've selected pantone colours for all of these as I understand this will ensure consistent printing in future.
However I'm now creating out brochure in InDesign, and when I use the same pantone colours they look considerably different than they do in illustrator, and have different CMYK/RGB values. I'm placing the logo and motifs into the brochure in native .ai format.
As a workaround I changed the inDesign colours to process, using the CMYK values from the illustrator logo, but even then the RGB values appear slightly different. However at least all the colours look the same - until, I export the brochure to PDF, when the inDesign colours look fine, but the logos I've placed from illustrator change colour drastically??
Is it pantone causing the issue? We are a tiny web-based company and are only ever going to be printing business cards and a small number of brochures, perhaps occasional headed letters (not using pre-printed headed paper) so maybe it just doesn't matter and I should stick with ordinary CMYK colours?
I am using CS6, and have synced colours in Bridge.
Any help would be massively appreciated as I've exhausted Google and am helpless as to where to turn next!
Thanks,
Natasha

Answer 1

I've selected pantone colours for all of these as I understand this will ensure consistent printing in future.
Using Pantone Colors for a CMYK job wouldn't necessarily ensure consistency for future printing—to get the same color appearance the printing conditions have to be the same or the values have to be adjusted to accommodate the new printing conditions. An extreme example would printing the same CMYK values on glossy paper on a sheetfed press and then on newsprint, the printed color would change in appearance.
What do I do if I'm working on images for web, or if i want to take illustrations etc from the CMYK brochure and change them to RGB for the website?
The displayed appearance of CMYK values—mixes you make yourself or specified Pantone mixes—depends on the document's assigned CMYK profile. Change the assigned profile from US SWOP to US Newsprint and you'll see what I mean (Edit>Assign Profiles).
So, if you are designing the printed materials for one printing condition, the document CMYK profile needs to be correct for that destination. In that case you can get the RGB equivalents (or hex values in CC2014) of your InDesign swatches via the color picker. If you want sRGB values make sure the document's assigned RGB profile is sRGB. Here my document's assigned CMYK and RGB profiles are the default US SWOP Coated and sRGB and the color picker is giving me the sRGB and hex equivalents of US SWOP's 50% magenta.
In the case of images, if a CMYK image was saved with its profile it can be accurately converted to any RGB space. In Photoshop you can use Save for Web to convert a copy of the CMYK image to sRGB or another RGB space, but if you are saving for web without an embedded profile sRGB would be best.
Alternatively you can leave your images as RGB in the layout and let the conversion to any CMYK destination happen at export or output. If you do that you have to watchout for color gamuts—RGB colors that are not printable. Turning on Overprint Preview shows you how RGB colors will change when they are eventually converted.