View Full Version here: : Imaging the Moon assistance please. Polarizing Filter?
08-03-2012, 05:19 PM
Took a picture of the Moon a while ago with the QHY8 (stacked). It was a part Moon and the results were good. I wanted to do the same again with the full Moon but found that I could not get the QHY settings (exposure Time) low enough to not get an overexposed image. Could I use a Poarizing filter to assist in this matter or will it mess up my colours?
I am wanting to do a saturated moon shot with the data. With a partial Moon I got away with it, but the full moon is just too bright. Once I start adding saturation in slow steps I get burnouts in the already too bright areas..
Any assistance would be a great help
08-03-2012, 06:47 PM
If it is clear tonight I'll have a go at the moon with my qhy8 and let you know.
Also you can just adjust saturation in the darker areas of the image to stop overblowing the highlights.
What settings did you use? I'd imagine you would be up around 1/1000th of a second to get the exposure right.
08-03-2012, 11:16 PM
A setting of about 0.001 seconds is about right.
See attached screen grab, the smearing is because I just setup to take a shot for you, I didn't set up the mount, so it isn't tracking.
A setting of 0.001 seconds gives okay exposure. Try 0.005 or lower and see how you go.
09-03-2012, 07:03 AM
Let me know if that solves your problems.
09-03-2012, 09:03 AM
Thanks Peter... Your picture looks like it is in colour? did you Debayer it, as mine takes the image in B&W or do you have your settings set a colour.
Anyway yours does not seem as bright as my image and this would be good. I have used the settings you have used and I even tried to add and extra zero 0.0001 with not better result. I think 0.001 is the lowest you can get. I have also noticed that you have used the CCD Labs Q8 selection for your camera. Is yours a QYH8 as I use the QHY8 camera from the selection? I am using Ver 2 of Nebulosity..
I think I might have to use a polarising filter (adjustable one) but I have not been able to find any information about using these for Astrophotography.
Really appreciate you assistance
09-03-2012, 09:27 AM
I am using the original QHY8, but I am running on a Mac under OSX.
Are your gain and other settings the same as mine?
I am using the default settings, which grabs the image in colour.
There is really no need for a filter, the camera shutter can be set fast enough to cope. If you do use a filter an ND filter may work better, or youcould stop down your scope a bit perhaps.
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