Lightroom has a brightness slider in the print module but the effect is not apparent until you print or export. It is best to run a few test prints using different settings, perhaps using the tone curve in Photoshop. Once you find the optimum settings you could record an action which can then be run on a batch of images in a folder.
How will these images be printed? Are you using your own printer, or are they going to an outside printing source?
In Photoshop, I'm assuming you're using a Curves adjustment layer as a printer target adjustment to brighten the image for print. In Lightroom we can do a similar thing using Virtual Copies of the images synced to Develop Module changes. Very fast and efficient.
You need to print a test image to see how it reproduces on the paper/ink combination you are using for the project, then make appropriate adjustments to the images in Photoshop or Lightroom.
I use Photoshop to adjust my images. Would Lightroom be better, to get a more accurate transition from screen to print?
Whether to use Lr vs Photoshop for editing your dark images all depends....
They both use the same camera raw engine for editing and have mostly the same capabilities however you can't work in layers in Lr and you can't sync adjustments across multiple images in Ps without creating an Action or using a Script. Therefore if adjusting one image to the correct exposure level (or other) and then syncing the rest of the images in a couple of clicks sounds like a time saving method then you might consider starting off with Lr to see where you land.
Read more about syncing editing adjustments here: Develop module options in Photoshop Lightroom
With regards to getting more accuracy with the output files you may also want to try the Soft Proofing feature to simulate the final print unless this is going to be printed on a commercial printing press. See more info about Soft Proofing in the same link above.
Can you provide more information on the rest of your workflow e.g. what application are you using to layout the book? InDesign or other, who is printing it for you? Is it going to be printed on a digital printer or a commercial sheet fed press? What kind of paper will it be printed on? Does the printer have spec's for how they want the files delivered in? Will your final output be press quality pdfs?
Can you post one of the images as well to see if we can recommend some editing adjustments?
I should also mention that the final product is being laid out in InDesign.
Soft-proofing will help you do an on-screen simulation of the final printing conditions, but only if:
- Your display profile is current and accurate
- Your images contain embedded profiles
- Your color management settings are appropriate for the job
- You've set up soft-proofing properly
If all that is true, when soft-proofing is enabled you should get a very good (though not perfect) preview of how the image will look when printed.
If you've set up color management so that you can soft-proof reliably in Photoshop, you can also do the same in InDesign. If your color management settings are consistent across your images, Photoshop, and InDesign, in theory you should be able to soft-proof in both programs to anticipate how the images will look in the layout when printed.
But if you haven't done this before, you'll probably have to spend some time studying how it all works. There are a lot of switches and options that all have to be set up in a particular way to achieve a proper simulation of the print.
The best thing to do is talk to the company who will run the press. They should have previous experience with many customers using Photoshop with InDesign who don't want to waste time and money on bad prints. Ask them questions like these:
- What color management settings do they recommend for Photoshop and InDesign?
- What profile should be used for soft-proofing? (A good shop should be able to provide an output profile to you)
- What are the exact settings for handing off the InDesign project to them? (like a PDF preset)
- Do they have some kind of proofing system where images can be checked before the final press run?