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Old 14-03-2008, 04:25 AM
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skwinty (Steve)
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Updated noise from a blunt tool

Hello and thanks to all for your feedback. It has brought about a revision of my poorly interpreted review of the subject matter. I have included some other aspects including an insert from Peter Ward.
Tomorrow when I get home I will stop at the hardware store and purchase a small spirit level and large protractor to ensure accuracy in polar aligning my EQ6. So Eric "ezi style" I will get out there this weekend and practice what I preach. Hope the weather holds.
Please comment on the updated pdf as I am not an expert ( ex = has been spert = drip under pressure) but trying very hard to sharpen my blunt edges.
regards
Steve
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File Type: pdf Updated noises from a blunt tool.pdf (55.7 KB, 44 views)
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Old 14-03-2008, 05:39 AM
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Bassnut (Fred)
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Nice work Steve, much better and very comprehensive.
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Old 14-03-2008, 06:09 AM
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skwinty (Steve)
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Thanks Fred
Makes the effort worth while, especially for me as it forces me to get to grips with the complexities of this hobby.
Its difficult trying to do it alone without others showing you the error of your ways.
Regards
Steve
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Old 14-03-2008, 08:58 AM
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Very good presentation, beautiful reminder :-)
Could you perhaps add couple of explanations, for newbies?
Some may be a bit confused in the beginning with very concise language in the document...
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Old 14-03-2008, 04:30 PM
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iceman (Mike)
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Nice information. A good mix of tips and tricks for newbies and those still learning.
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Old 14-03-2008, 11:36 PM
jase (Jason)
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Tip #37:

The signal to noise (S/N) ratio of a CCD image increases linearly with the square root of the exposure time. This means that quadrupling the exposure time doubles the S/N ratio. So take the longest *effective* exposure you can. Such advice applies to all CCD imaging and is especially important for narrowband imaging because of the small amount of signal passing through the filter.
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Old 15-03-2008, 01:16 AM
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skwinty (Steve)
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Quote:
Originally Posted by jase View Post
Tip #37:

The signal to noise (S/N) ratio of a CCD image increases linearly with the square root of the exposure time. This means that quadrupling the exposure time doubles the S/N ratio. So take the longest *effective* exposure you can. Such advice applies to all CCD imaging and is especially important for narrowband imaging because of the small amount of signal passing through the filter.
Hi Jase
Thanks for tip #37
Will add to my study list.
Please feel free to suggest more as I still have a long way to go with my studies on Astronomical Imaging.
I appreciate all feedback that is constructive and helps me to get to grips with the complex issues.
Regards
Steve
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Old 15-03-2008, 01:40 AM
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EzyStyles (Eric)
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Quote:
Originally Posted by skwinty View Post
Tomorrow when I get home I will stop at the hardware store and purchase a small spirit level and large protractor to ensure accuracy in polar aligning my EQ6. So Eric "ezi style" I will get out there this weekend and practice what I preach.
Nice one steve, looking forward to your images. what camera are you using btw? you sure sound like you know what you are doing with those informative .pdf files you seem to worship that HAIP book following it verbatim.
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Old 15-03-2008, 01:58 AM
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skwinty (Steve)
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Hi Eric
Got the spirit level and a fancy angle meter today.
I have a Canon 40DH.
I would hardly say verbatim. If it was I wouldnt be making so many mistakes. I must say that I do love that manual as it is the only book that I have come across that deals extensively with the issue and uses mathematics to illustrate the point.
It is quite difficult to absorb all this data without participation from other people like those who offer constructive and positive feedback. Unfortunately there are not as many amateurs here in Cape Town who practise Astrophotography. I also tend to plug the HAIP so if the authors get to see my posts they dont sue me for sharing their secrets.
Regards
Steve
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