Player One "dead pixel suppresion"

[Krzysztof z Bagien]

From their description:
"The planetary cameras from Player One Astronomy have DPS (Dead Pixel Suppression) technology. The DPS is anaylse many dark frames to find out thoes fixed abnormal pixel and record the map in camera memory. In imaging, each exposure frames, thoes position of dead pixels will be given a median value according to the active pixels around that abnormal pixel."

Now - does anyone know how that actually works and whether it can be turned off? I've seen some talk about it at CN forum, but answers from Player One representative didn't really shed any light on that subject. Pictures they show on their website look more like a hot pixel removal to me.

[admin]

Hi,

that's interesting, I have heard rumours about similar things on other brands, but nothing with quite as much detail. I would not be surprised if most/all brands are doing this as any who are not would appear to have 'worse' sensors than those who do...

The SDK doesn't offer any way to turn this on or off, or to find out details about it. I suspect that if you really wanted to you could work out which pixels are being affected by capturing lots of frames with flat illumination (~60% brightness) and analysing them to look for pixels with abnormally low variability in their brightness (all pixels will have variability due to shot noise, but if a pixel value is coming from a mean or median of 2 or more neighbours then the variability of that pixel will be lower).

On the whole, for general astrohphotography, I suspect this sort of thing works in the favour of the photographer, giving cleaner images. If you were doing scientific measurements where the values of individual pixels matter then you might feel differently about it!

cheers,

Robin

[Krzysztof z Bagien]

Thank you!
I guess we'll have to live with that, though it would be nice to have some control over it.