Did a little test with a zone style exposure series and -compensation with Lightroom and PhotoLab version 7.4 on Mac. Have a look:
Top row: Bracketed exposures as seen in Lightroom
Middle row: Virtual copies compensated according to exposure offset (Lr)
Bottom row: Compensated copies as seen im PhotoLab 7
While all compensated copies should have close to equal RGB values, we can see some differences between Lr and DPL. Note that the two brightest images have highlights burnt to different degrees, which allows us to see how the apps deal with it.
- PhotoLab is, in absolute terms, closer to what the RGB values should be (122,122,122)
- PhotoLab’s third image from right is too bright
- PhotoLab can compensate ±4EV while Lr goes to ±5EV (corrected the leftmost image in the .dop sidecar file as mentioned here. The rightmost image cannot be lifted with editing the .dop file.
- The rightmost image is darker because of massively burnt highlights, which leaves only the left (dark) part of the bell-shaped distribution in the histogram when exposure is compensated.
- Lightroom produces a fairly even set of compensated images, but they are a tad too dark (105 instead of 122)
Imo, Lightroom handles the highlights better in the sense of a more even compensation. DPL has this brighter zone 8 image and its limitations at ±4EV…which can be worked around by setting exposure bias with a text editor in the .dop sidecar(s). Note that both ExposureBias values must be changed (in the Base and Overrides sections)
Images taken with a Canon EOS R7 with a FF 28mm lens. Optical corrections only.