White Balance Follies

Few people (at least not those that regularly read this web site) doubt the benefits of shooting in raw mode. But, for those that still don’t appreciate the benefits of working with raw files, here are a couple of examples that I recently created to demonstrate this issue to some students at one of my seminars.

The purpose of this exercise was that since I almost never shoot JPG, I didn’t have on hand any examples with which to demonstrate some of the limitations that JPG files have when strong to extreme manipulations are required. So, to rectify this I set one of my cameras to shoot combined JPG and raw, and took my dogs for a walk around the block.

Above is a frame taken in late afternoon sunlight. The camera’s white balance was set to Auto. The JPG and the raw files were virtually identical.

Below are white balance conversions done in Lightroom. In both cases I tried to normalize the shot by clicking on the bike’s license plate as a white reference. The results speak for themselves.

From JPG From raw

The frame on the left is the best white balance that can be achieved from the JPG file, while the one on the right is from the raw file. As can be seen, the raw file can have the warmth of the late afternoon sun completely removed, and post exposure white balance can be easily achieved, while the JPG, though some adjustment can be achieved, simply can’t be properly white balanced after exposure.


Exposure Follies

Similar results are found when extreme exposure adjustments are needed. Above is a strongly back lit shot with hardly any visible detail in the shadow areas. Below are two conversions, one from the JPG file and the other from the raw.

From JPG From raw

In both cases maximum exposure recovery and Fill Light adjustment were used in Lightroom. As can be seen the JPG has almost completely lost colour information, while the raw file still retains a reasonable amount of colour in the shadow areas.

The Bottom Line

These are just two simple examples of how working with a fully baked JPG file out of the camera seriously reduces the ability that one has to fix white balance and exposure problems, especially when strong adjustments are needed. There simply isn’t enough information available in a JPG to do the job as well as with raw files.

November, 2007