Cool Tech | BRNO baLens White Balance Tool

White balance.  The color of white.  Seems so simple but that’s because our eyes are so good at adapting to color changes.  Put a white piece of paper under a yellow/orange table lamp, or a sickly green fluorescent light, or oddball magenta sodium vapor in an industrial or gym setting.  Our eyes will make that white page look white.  Or at least white’ish.  But the camera needs to make adjustments to compensate.  Either automatically (choosing the AutoWB setting), through a fixed preset (ex. Incendescent or Fluorescent), or via a custom white balance.  The latter is not always as easy as it sounds if you don’t have a reliable neutral reference handy.  Enter a little gizmo called the baLens white balance lens cap from BRNO.

BRNO BaLens White Balance Cap

Many moons ago on a whim I purchased this little gizmo.  Nothing more than a lens cap (available in different sizes) with a hole in the middle filled with a translucent white dome.  The concept is simple: attach the baLens cap in place of your standard cap, aim your camera at the light source illuminating your subject, and take a picture.  What will be captured is just a dull gray frame (likely heavily vignetted depending on your focal length).  But you can then use that image as a reference for your camera’s custom white balance preset.  The result is that you now have an accurate white balance reference based on the light coming at your subject, rather than referencing the light bouncing off of it.  And if you feel that white balance is still too cool you can swap domes for one that is slightly blue which will then bias the custom WB a little warmer (more yellow added to compensate).

Why do this?  Better color.

Unfortunately I never paid much attention to it after pulling it out of the box.  It’s too bad as I’ve since wasted a healthy amount of time correcting for weird, funky arena light when shooting hockey and ringette.  In such an environment I figured there is a huge sheet of white ice in front of me – what better source for a white balance reference?

Turns out the ice doesn’t work so well.  Arena ice isn’t a truly neutral white.  And the lights above are generally whacky, so combine the two and you can get some weird results.

This week I cracked out the baLens (after poking around trying to find the damn thing) and tried it at the local arena.  This particular location forced me to shoot through the plexiglass, which adds its own color tint (and unfortunately robs me of light and contrast and clarity but that’s another beef).  I fitted the BaLens with the warming dome, aimed through the glass up at the lights, and fired off a frame.  Referencing that I created a custom WB preset on my Nikon D3s, pulled the cap, and took a test frame.

Well, sonuva.

Image captured with BaLens WB preset and left “As Shot” in Adobe Camera Raw.

According to my LCD things looked better compared to the custom WB I made previously based on the ice as my reference.  Colors were more natural and there was no odd green or blue or yellow bias.  Yes, the image was pleasingly warm thanks to the warming dome.  But not at all exaggerated.  Supporting this observation was a fairly balanced histogram with just a slight edge in the red channel.  I shot the game with this preset locked in and after downloading the images afterwards things looked just as good on my color corrected monitor.  This helped streamline my processing workflow greatly as I just left the WB “As Shot” in Adobe Camera Raw.  No jerking around with tweaking the ice-based WB setting as I had done in the past.

Shouldn’t my camera’s AutoWB setting work just as well?

In a perfect world, yes.  But there is still an inconsistency among different cameras in their ability to render neutral colors.  Relying on AWB for the duration of a shoot will yield mixed results as the contents of the frame are continuously changing (think of the players’ jersey colors combining, or elements of advertising banners on the boards, or colored arena walls – all of this is influencing the AWB system and changing constantly).  The result will be variation from shot-to-shot which adds to post-processing burden (can’t just make a global correction).  And creating a custom WB preset depends on using a properly neutral reference, plus without an intermediate material you can’t really shoot the light source directly.  You can refine the WB on many cameras across a 2D spectrum of color from blue-to-amber on one axis and green-to-magenta on the other, but that involves additional fiddling and is pure trial and error (made worse by the fact that your camera’s LCD isn’t that accurate to use as a reference).  The little cap is just very convenient.

Final Thoughts

This particular arena has reasonably constant lighting so the next test will be in some of the older venues where things are more flaky.  But for right now a white balancing lens cap, with its ability to directly reference the light source rather than the reflected light, and with a slight warm bias to gently push color saturation, seems to be a great solution for improving color in challenging lighting conditions and streamlining post-processing workflow.  It’s a rip-off purely from a cost-of-goods standpoint, but BRNO does speak to strict quality controls to make sure the domes are truly neutral so I’ll take them at their word.  The results would support those claims.  But based on a return on investment for a working pro (which I am not, just an enthusiastic amateur) if this type of product yields regular time savings in post-processing workflow over volumes of images then it should cover itself in a relatively short period.  Your mileage may vary.