First time PHD2 issue

Discussion of using SharpCap for Deep Sky Imaging
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psy1280
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Joined: Wed Oct 24, 2018 4:52 pm

First time PHD2 issue

Post by psy1280 »

I'm trying to make the leap from EAA to AP. I just tried to set up PHD2's Dark Library. When I go to the screen and "loop" (with the cap on the guide scope) I get this image. From all the YouTube images I've seen there shouldn't be so much noise...shouldn't it be black? The dark library seemed to go without a glitch. Any feedback would be most welcomed
phd2.png
phd2.png (302.64 KiB) Viewed 255 times
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oopfan
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Re: First time PHD2 issue

Post by oopfan »

Joe,

That looks fairly typical. This is what my darks look like using a CMOS guide camera:
Altair 290M typical dark.jpg
Altair 290M typical dark.jpg (135.71 KiB) Viewed 252 times
Brian
psy1280
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Re: First time PHD2 issue

Post by psy1280 »

Thank you Brian,
Let me elaborate. The image I sent is 50 times worse then it appears in the attachment. Both with the cap on or off, the screen is totally mottled. With the cap off (daytime in my home) the white screen looks like it has a million dead ants :P
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oopfan
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Re: First time PHD2 issue

Post by oopfan »

Joe, what do you want me to say, that you've got a bad camera? Have you tried pointing it out a window to see if you get an image in the distance during daytime? There is a reason why it looks noisy. You are not imaging anything, so when SharpCap stretches it, all it can stretch is noise, so that is what you get. As soon as you point at the stars or across the river, those things are much brighter than the noise. Now when SharpCap stretches it, the noise goes (nearly) black because the thing you are imaging is so much brighter.
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turfpit
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Re: First time PHD2 issue

Post by turfpit »

Joe

If you are at 'first time' stage with PHD2 then consider setting up a profile where the Camera is Simulator and Mount is On-camera - see manual page 11. This will enable working through the usage of PHD2 in the warmth and comfort of your home without a camera or mount involved.

I spent a couple of days working through the manual at my desk with the simulator. This enable me at first testing session outside to achieve up to 25m exposures with an Ha filter viewtopic.php?f=9&t=3867. This was using an ST4 cable between camera and mount (Celestron AVX).

This is how my QYH5LII-M, with cap on and set to 2s exposure, appears in PHD2. I cannot see any issue with your display at 0.1s. Better to judge when outside in the dark.

Screenshot from 2021-03-26 15-00-51.png
Screenshot from 2021-03-26 15-00-51.png (274.15 KiB) Viewed 246 times


Subsequently I have managed this in testing - 11x300s guided, all down to practising in the house with the simulator.:


M51-11x300s_filtered.jpg
M51-11x300s_filtered.jpg (373.24 KiB) Viewed 246 times


Dave
psy1280
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Re: First time PHD2 issue

Post by psy1280 »

Much thanks Brian and Dave, I believe I'm good to go. And the suggestion about using the simulator is a great idea. Appreciate your feedback.

Joe
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