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Old 17-07-2010, 09:21 PM
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mldee (Mike)
Photon sorter

mldee is offline
 
Join Date: Aug 2008
Location: Near Warwick, Qld, Australia
Posts: 657
I still use the white T shirt stretched over the front of the OTA, and point it towards a clear early evening sky (5.30 ish at the moment). Then try a range of exposures or read the histograms), taking at least 10 each at various speeds. The optimal set will depend on the ambient light and the thickness of the T shirt

Apparently the aim with the flats is to get a set that have a mean reading of around 25000 in the pixel data.

I guess you don't do bias with the 1000d do you? If you do, just put the front cap on the OTA and take 20+ shots at 1/1000 or so.

Stack everything to get a master flat and a master bias. Then subtract the bias from the flat(s). Sounds so easy......Nebulosity will do it for you, as no doubt other software will as well.

I must admit, once you move to a ccd, Neb is good all round program and the tutorials in the Help section of the website are really simple and clear.

At least this method only costs an old T shirt.

Good luck
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