Ideal Exposure Time link to hidden loft

Hi I am reading page 163 of the manual on exposure statistics. There is a link to hiddenloft.com/notes/subexposures.pdf
It is not there. I really want to understand this feature. Can someone post the PDF?

Does SGP have a way to measure the light coming off the object you are imagining and then allow you to read the background so you come up with the best setting possible?

The mean adu and the min and max can be misleading if you are in a light polluted area.

I think I have it somewhere - or at least the spreadsheet. Let me see if I can find it.

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Thank you

Joe

usually these things can be found on archive.org…

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Thank now I have to figure out how to use the formulas. I appreciate your help.

Joe

On page 2 of the paper that it is used as reference for calculating the exposure time it says that, for calculating the exposure time, you should use a “dark.substracted background” and I understand that this is the ADU count for the background of your Light less the ADU count of a Dark frame.

Ir seems to me that SGP is not substracting the dark-background count so all recomended exposure times that I get are too short.

Am I right?,

Thanks

i don’t think SGP will calibrate your images, but don’t know for sure. some image acquisition packages will calibrate before saving the camera images but IMO its a crazy thing to do. personally i want the unmodified sensor data so that i can calibrate it myself, in case something goes wrong with the calibration.

rob

That is why SGP should have the option for the user to input the dark-background value so SGP it can provide a usefull recomended exposure time

Thank you for posting the PDF, it is way over my head, I don’t even remember from High School how to solve from the square root of the number of subframe. So of the input data is over my head as well. I am hoping Saturday night here in Arlington VA is cloudless, I want to shoot more subs of M 51. I a lot blaffled what to look for in the SPG stats as it could just be registering a lot of my 8/9 bortel zone. So I am just not blinding guessing where to look what to do. There are tons of videos regarding everything in SPG but very little on how to capture a proper set of subframe exposures.

I hope I can be directed to a resource I can understand so I am not just shooting in the dark.

Thanks,

Joe

This is a very noise 39 subs 1 minute each with gain at 72 and offset at 12.

Call this beginner luck I had gain and off set at 10
My subs where 5 minutes 10 minutes and a single 15 minute, processed in PixInsight. I was a bit blowen away my this.

I use a Orion sky glow filter and a ZWO 1600 OSC.

Appreciate any help and advice.

Hope the folks at SPG publish more exposure advise. THANKS.

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