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Old 27-04-2008, 06:41 PM
Alchemy (Clive)
Quietly watching

Alchemy is offline
Join Date: Jul 2007
Location: Yarra Junction
Posts: 3,044
thanks for your input guys.

firstly deano ... i checked out seeker372011, s post and quote
gain was 20% and offset was 130-the auto offset didnt work in nebulosity for some reason..the shadows were clipped so next time I will need to fix those setting
thanks for your suggestion its possible he hadnt used it in the appropriate manner perhaps.

1ponders .... im familiar with the usual process of flats, darks, bias, flat/darks. and know how i would deal with these for a point and shoot camera. Again thanks for your ideas.

The problem that occurs to me is this
1. the qhy8 has an adjustment "OFFSET" , as best as i can guess/deduce, this is to do with the bias signal , as you suggest preset in the factory. the settingof the OFFSET counteracts this (so the WIN4AIP suggests). i guess is this deduction correct?
2. If i am correct then shooting bias frames with varying offset values will produce frames with varying amounts of bias noise, the frame that has the LEAST noise is the correct OFFSET value..... this requires some extreme stretching to detect.
3.As there is an OFFSET setting it HAS to be set at something.... is my deduction correct or even logical. I have actually PM ed a number of IIS QHY8 owners and so far no-one has a real idea of what its settings are , other than to google someone elses images and copy the settings.
4. If this fails then trial and error shooting of some exposures of normal length at an object of wide brightness scales with varying OFFSET values and comparing the results.

there has to be a logical and simple answer to this , i can tell you NO_oNe using the camera i know of has a clue how to set it. It should be in the camera documentaton , much as collimation comes with a newt telescope.

Again thanks for taking the time to answer and sugestions.

maybee JASE, SJASTRO, GAMMA, STROGMANMIKE, BASSNUT, or PETERWARD or anyone who has used this can advise.
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