I was just reading a post in the yahoo toucam users group, and found an interesting article a guy posted relating to "ringing" when doing an avi of Jupiter. He also calls it "onion rings".
I quote his post:
most of the time the onion-ring effect is caused by incorrect capture parameters. The brightness slider has to be set to the absolute middle, since the brightness is calculated into the image by the cam/driver, in the middle position it does nothing to the image. Adjust image brightness by exposure time and gain only!
With increased brightness settings, the chosen gain will be too low to expose the fainter areas around Jupiters edge correctly, the underexposure will result in a poor dynamic range causing the ring effect.
In addition, leave the gamma slider at 0, the Toucam works almost linear with this setting. Higher gamma settings will compress the subtle highlights of Jupiter and result in a loss of detail rendering.
End quote:
Interesting stuff, as I always seem to have a problem with the rendering myself and get the dreaded onion rings at times.
Anyone else have any thoughts on the above.
hmm interesting Peter, i've heard a few of those things from bird before too (especially gamma at 0). Gamma at 0 doesn't actually mean 0 gamma, it means something like "maximum contrast", and if you want "low" or zero gamma, you actually have to set it to 1.
Didn't know about the brightness setting, but will take that into consideration next time.. thanks for the heads-up.
btw, you can quote with [ quote] and [ /quote] (without the spaces).
Thanks heaps for that Peter. The onion ring problem has been driving me NUTS. That's why I haven't been posting any shots. (apart from Strikers clouds)
No Paul, you might want to post that one one yahoo toucam group. They seem to be fairly clued up on things there. It will require that you sign up if you want to post there, but it is free.
Further to my info on the ringing problems with the toucam, there is quite a bit of discussion going on about this on that discussion group if anyone is interested.
Paul R. funny about the chequer board effect, mine did it last night as well. It just popped up out of the blue, went away after I gave the gain a blast of flat out as well as the gamma. I dont know what caused it or why it went away when I did it, but I will ask if anyone has any ideas in the Toucam group.