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Old 28-05-2008, 02:37 PM
ozstockman (Mike)
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ozstockman is offline
 
Join Date: Mar 2007
Location: Kenmore Hills, Brisbane, QLD
Posts: 392
QHY8 bias and flats

Hi guys,

I had a chance yesterday to get a first light with my QHY8 and got a wonderful result. See the image attached. It's 7x400sec light frames + 4 flats. The frames were calibrated in MaximDL and stacked in DSS and final processing was done in PS. Autoguided with 8" SCT and QHY5 using PHD, frames taken with ED80mm f/6.8 APO and QHY8

Taking lights does not seem to be a big problem especially after Theo kindly explained some basic stuff about offset and gain to me wasting his Friday night time :-)

I have however few questions about taking flats and bias frames with QHY8 because I don't think I did it right.

1)Should bias and flat frames be taken with the same gain and offset settings as for light frames? I forgot what settings I had for light frames for the image below and I guess this is why it's not the best result I could get with this great camera.

2) How to figure out the best exposure length for flats? I used to use Aperture priority mode in my Canon DSLR and the camera did it for me. But of course it's not possible to do with QHY8.

And if I get it right I shouldn't use binning for light frames if I want to get a color image, right? I used 2x2 binning and it seems that I lost all color details for this image.

thanks in advance,

Mike
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