2017-06-03

Blue, Black, White, or Gold dress

The internet meme of the coloured dress and the strange way so many people disagree on the colour is something known to photographers as white balance.

It is the way we see colour, and the fact we always see it in context of surroundings and lighting.

XKCD did a nice example in https://xkcd.com/1492/


The dresses are identical, the background makes all the difference.

A lot of the photographs I take are done under AWB (Automatic White Balance), as that usually works out the right white balance to apply. However, I was shocked in a recent blog post when I included the picture here..


That is blue, a rather nice shade of blue. In fact, I have a blue of that shade in stock even, though not in PLA. It is nice, but it is not reality. The cube was in fact green. It did not matter for the blog post so I left it, but it is one of the few occasions where AWB has got it way wrong.

Basically the colour of my worktop/desk around it was the culprit. I set a fixed 5200K WB and took another shot of the same cube...


This is much closer to reality, but perhaps not quite as dark a green as it should be - at least it is green! Of course, some of that is how my monitor displays the image.


Interestingly, taking a picture of the cube against my monitor looks good.



Isn't colour a fun thing :-)

5 comments:

  1. Before you go any deeper...

    http://www.infinitecat.com/

    You may recurr the internet

    ReplyDelete
  2. Lies, dammed lies and camera white balance, eh?

    ReplyDelete
  3. What if you set the WB manually using a white sheet of cardboard?

    ReplyDelete
    Replies
    1. This is what I end up doing for pretty much any indoor shooting now.

      Delete
  4. When I used to work for Racal we made monitors for AWACS & Siemens were our customer.

    Suffice it to say English "good enough" met German "these monitors are scratched, misconverged, etc etc".

    As an adjunct to the whole mess a colleague of mine (Mike Day) actually convinced the NPL (www.npl.co.uk) to change their definition of white. Not by much to be sure but it changed all the same.

    "Colour" is indeed fun - and changeable....

    ReplyDelete

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