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sean90291
2007 July 3rd, 08:26
Just was curious about others' experiences with color shifting and the HV20. I noticed while doing a couple tests yesterday that the distinctly violet flowers (a dark purple actually) were reading as distinctly blue on my LCD and viewfinder. I tried changing white balance and even changing out of Cine mode, but those purple flowers stayed very blue in the LCD/viewfinder. Thoughts?

EDIT: It seems what I'm observing might be a Canon sensor quirk. I took a picture of the same flowers using my Canon PowerShot still camera, and took a still using the HV20. The purple is the exact same "blue" from both cameras. At least I know my HV20 isn't "broken."

um3k
2007 July 3rd, 10:55
Violet can be an issue for any camera, digital or film. The red detecting cone cells in the human eye also detect violet light, which is what gives it its color (otherwise it would just be deep blue). Most digital cameras do not share this unusual property, and thus see the flowers as blue.

sean90291
2007 July 3rd, 11:57
Ah, of course. I do remember reading something about violet being an issue for cameras. Thanks for that info. Good to know!

24Peter
2007 July 3rd, 12:33
I do notice the auto white balance on the HV20 shifts a bit more than I'd expect and/or stays "locked" on an inaccurate balance, again more than I'd expect. But I never really used AWB before. Don't know if that's contributing to what you're experiencing or not Sean...

sean90291
2007 July 3rd, 13:17
I manual white balanced, and tried all the default white balance settings (shade, tungsten, sun, etc.) The violet looked blue in all white balances.

Erik Bien
2007 July 3rd, 15:42
My GL-2 exhibits the same symptoms, but I think um3k is right: most sensors seem to have a bit of "wierdness" capturing violet/purple/mauve/fuscia colors compared to how they look by eye ...

PWHerman
2007 July 3rd, 16:27
There were some pretty violet flowers I took some video of last night on the HV20 and they came out pretty darn good (although they're a little more dark and on the purple side, just as you said). I had it in 60i/CineMode with the "Shade" WB set...very weird that it stayed the same way for you through all of the different WB's.

I was taking shots of some fireworks at my friends' house and the flowers were sitting there, so I just panned over and taped them for like 5 seconds, haha. After playing the video back, they indeed look very vibrant and accurate (to me at least). I guess this little symptom is give or take.

um3k
2007 July 3rd, 18:36
Well, there are, in a way, two sorts of violet: true violet, which is a spectral color in the range of 380–450 nm (wikipedia); and simulated violet, which is created by mixing red and blue light. Both types of violet occur naturally. No computer display (or TV for that matter) can show true violet, they all mix red and blue. Likewise, many cameras can't properly capture true violet. They usually reproduce simulated violet just fine, however, and I suspect this is why it worked for PWH. Most likely, the flower he recorded was simulated violet, while the flower Sean shot was true violet.

I do have an experiment for you, Sean: try shooting the violet flower again, but this time underexpose the video. Depending on the specific cause of the color problems, it just may help (but probably not). I have this hypothesis, you see...

In addition, I wonder if my Powershot G3 has the same problem. *ponders, twiddling thumbs*