: Using Lightroom photos for print in CMYK (Exporting into ProPhoto vs original photo colorspace) From what I understand, Lightroom won't directly export into CMYK. One has to choose an RGB colorspace

Posted in: #AdobeLightroom #Cmyk #ColorConversion #ColorProfile #PrintProduction

From what I understand, Lightroom won't directly export into CMYK. One has to choose an RGB colorspace such as sRGB, adobeRGB or ProPhoto RGB and then do the CMYK conversion either in Photoshop or InDesign.

I'm trying to understand how to best convert for print (retain as much gamut/gradation as possible?).

Given that,
- the photos come from various sources (including cameras that shoot sRGB, adobeRGB and raw)
- not all of the photos will be fine-tuned inside Lr (some will just be cataloged, others will be cropped and rotated)
- the final intent is creating a CMYK book in InDesign

I'm detecting the following things I'm not clear about:

If you Export an image into the same color space as the original won't Lr internally convert it into ProPhoto RGB before converting it back into the original color space? wouldn't that be wasteful?

will Lr convert (internally) the photo into ProPhoto RGB even if you don't perform any color adjustment on it?

How much detail is preserved when converting an 8bit sRGB file into a 16bit ProPhoto RGB? From what I can see, the gamut of ProPhoto RGB (ROMM RGB) is a superset of adobeRGB/sRGB but would 16bit be enough for a lossless conversion?
ProPhoto RGB seems the closest in terms of gamut to CMYK - does it mean that this would be best choice for exporting my images (doubled by the fact that the images are edited in it anyways)?