Today’s Question: My problem is that when I send a book created in Lightroom Classic to Blurb to be printed it comes back at least 1/2 to 1 stop too dark. Now I have to go in and adjust all my photos by that amount to assure that my books will be printed correctly. Any thoughts on why? Also, how can I adjust only the exposure on a group of photos by the same amount to correct this issue?
Tim’s Quick Answer: It sounds like you may have prepared the book with a monitor display that is too bright, leading to dark printing. I would make sure to calibrate your display (https://timgrey.me/calibrite) and then adjust the images. You can use the Quick Develop section in the Library module to quickly apply a relative adjustment to multiple photos.
More Detail: In my experience the results with Blurb photo books have been very good, meaning the printed photos are a close match to what I see on my calibrated display. Because a typical uncalibrated display is about one stop too bright, I suspect that is the issue leading to dark printing for your Blurb books.
The first step would be to calibrate your display, using something like the Calibrite ColorChecker Display package (https://timgrey.me/calibrite). I would expect that the adjustment to the brightness as part of the calibration process will reveal that the images are too dark.
Regardless of whether the calibration is to blame, if the images that appear in the book are too dark you can brighten them in batch to produce a new book. Start by going to the collection that contains the images from the book, which would generally mean the collection created when the book was saved in Lightroom Classic.
Select all of the photos, and then go to the Library module and make sure you are in the grid view display, not the loupe view display, so you are viewing thumbnails of the selected images in the main preview area. Then go to the Quick Develop section on the right panel in the Library module and adjust the Exposure as needed.
Clicking on the double left or right arrow for Exposure in Quick Develop will decrease or increase exposure by one stop, respectively. The left and right single arrow buttons adjust exposure in one-third of a stop increments. With the Quick Develop adjustments you are applying a relative adjustment to each image, rather than an absolute change in value, which makes Quick Develop perfect for this type of scenario.