kat.hayes said:
1. How do you calibrate a laptop when you might be using it with different lighting conditions, varying from very low light to household lighting? The settings it is now configured at will likely make it not display nicely in very low light, etc. Is the idea to make a different calibration profile based on different lighting conditions I may use and to change them as needed?
Calibration is usually made for a specific settings - including environment. Some devices can measure and take into account environment light (although it's advisable to set it within proper limits), but if you need to work with high precision, the environment itself needs to be "neutral" enough. and the monitor set to a proper brightness (usually around 100/120 cd/m2), and white point (usually D50 or D65).
Thereby, calibrating a laptop for many different light conditions it's difficult - it's not only the brightness, but the color of the light itself. You may make profiles for different brightness levels, but to work precisely, you need the proper environment.
kat.hayes said:
2. In Lightroom, is selecting the .icc profile from my printing vendor before sending my files to the printer just to simulate to me how it will look for editing, or is it necessary to bake it in to the files so they print accurately?
LR allows to use ICC profiles in two different places. One is the Develop module, where it is used for proofing. It allows LR to simulate ink and paper, and let you adjust settings for that combination. Automatic processing via ICC profiles can do a lot, but the result may still need some tweaks to take into account the limitations of papers and inks - i.e. contrast limitations. The profile select for proofing is just used for display purposes, the original file is never changed, and if you create proof copies, they are just virtual copies to which LR associates the profile in its database.
The other is the Print module - but only when you let LR manage colors - under Color Management, a printer/paper profile is selected. Of course, the same profile used for proofing should be selected, note that LR doesn't select it automatically. Remember in this case you *must* also disable any color management in the printer driver settings, otherwise the image will be color-managed twice, usually with bad results.
You may select "Managed by printer" under color management. In this case LR doesn't use its internal color management engine (it's the same ACE used by Photoshop), but just sends the data to the printer. In this case, the desired ICC profile *must* be selected in the printer driver, and the OS color management engine will be usually used.
The ICC profile will be used only while printing - LR or the printer will apply the profile to the print data, no profile is "baked" into the original file.
If you export for printing, you should ask the print lab about the file format (but LR supports only JPEG) and ICC profile to embed, if any. In this case LR lets you choose what ICC profile to embed.