I bought the PRS-ACL1 to replace my clip-on LED light, which caused to much glare on the reading pane. The light reader's low light setting does cause some shadowing when reading area has low to ambient light in it. I have found by going to high it takes most of the shadowing away. I have used this light at night with no lights on in the bedroom with now shadowing in low or high. I have found this does not bother your significant other while they try to sleep. This also works great on those 14 hour flights when reading lights would annoy other passengers. So, even though it does have some shadow effects, I would rate this as excellent for the value.