Maybe I am missing the point but my understanding is that the histogram feature will aid in correct exposure and gain setting - especially for planetary work. The "rule of thumb" that seems to be out there is that Jupiter should be about a 50% histogram and Saturn 60 to 80%. Based on the histogram below - what peak should I use? Blue, white or red/green? Or, an I totally out in left fired??
Thanks
Wayne
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Histogram
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Re: Histogram
Hi,
I'm not sure that I can think of any good reason from my knowledge of how cameras work why you would want slightly different peaks for Jupiter and Saturn, but the basic advice is sound. What you are really trying to do is make sure that the histogram graphs aren't getting all the way to the right hand side (you are getting to about 80% with the red/green - no harm in going to ~90% as long as it is not getting out to 100%). In a similar way, you don't want the graphs (like the blue below) getting much below 50% for the histogram of the planet itself.
Your histogram below looks pretty well exposed to me - I would personally perhaps try to tweak everything about 5% higher, but I don't think it would make much practical difference. You have to also consider that you need to keep the exposure time down - 30ms or less - to make sure you freeze the seeing in your video frames.
cheers,
Robin
I'm not sure that I can think of any good reason from my knowledge of how cameras work why you would want slightly different peaks for Jupiter and Saturn, but the basic advice is sound. What you are really trying to do is make sure that the histogram graphs aren't getting all the way to the right hand side (you are getting to about 80% with the red/green - no harm in going to ~90% as long as it is not getting out to 100%). In a similar way, you don't want the graphs (like the blue below) getting much below 50% for the histogram of the planet itself.
Your histogram below looks pretty well exposed to me - I would personally perhaps try to tweak everything about 5% higher, but I don't think it would make much practical difference. You have to also consider that you need to keep the exposure time down - 30ms or less - to make sure you freeze the seeing in your video frames.
cheers,
Robin