Stars Not Detected & Bit Depth

Using SharpCap's Polar Alignment feature
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Amith
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Joined: Tue Mar 26, 2019 7:52 am

Stars Not Detected & Bit Depth

#1

Post by Amith »

Good day.

I have purchased the one year licence of sharpcap in roughly October last year. Since this time I have had very few clear nights but have had no success in using the Polar alignment feature.

I am in the Southern Hemisphere so do not have a pole star to work with. My issues is that I see stars very faintly moving on the screen but Sharpcap cannot lock onto those stars. It would rather lock onto the noise as opposed to the stars that are moving by. I have tried increasing gain as well as reducing the noise for it to pick up stars with no luck.

On my last clear night, it came up with a message stating that I need to try to increase my bit depth in order to increase the number of stars that is detected. I have no clue where the bit depth function is even after searching for it.

Is there any other info that I could use to help me with the Polar Align feature.

Side note: I am using a CPC800 on a wedge. I have successfully aligned with PHD2 but would rather use this as I've heard more success stories and been told it was faster to align with.

Clear Skies.
Amith Rajpal
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admin
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Re: Stars Not Detected & Bit Depth

#2

Post by admin »

Hi,

Have you tried working through the steps listed on the polar alignment troubleshooting page? https://www.sharpcap.co.uk/sharpcap/fea ... leshooting

Cheers, Robin
Amith
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Joined: Tue Mar 26, 2019 7:52 am

Re: Stars Not Detected & Bit Depth

#3

Post by Amith »

Hello.

Yes I have tried those options. I get close enough where I see the rings for the polar alignment process but it is still too few stars detected. I am not sure how to adjust gain on the ZWO120MC or even if there is an option for this camera so I have been using the Sharpcap built in gain.

My other concern is still the messaged that popped up stating that I need to increase my bit depth in order to have more stars show up.
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turfpit
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Re: Stars Not Detected & Bit Depth

#4

Post by turfpit »

Amith

Have a look at https://www.youtube.com/watch?v=ivlgbgNIeTU.

I see your CN thread https://www.cloudynights.com/topic/6554 ... bit-depth/ is throwing up some good ideas from people with the same ZWO camera.

See https://docs.sharpcap.co.uk/3.2/#Tips. The gain you ask about is shown here:

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Dave
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Re: Stars Not Detected & Bit Depth

#5

Post by admin »

Hi,

I think the message you're referring to is a general hint that pops up when you are taking exposures of 5 seconds or more with a bit depth of 8. It's just letting you know that there may be more detail available you switch to a higher bit depth, but it's not compulsory and it probably won't help you in the polar alignment routine so you can ignore that.

There should be a gain control in the control panel on the right hand side near to the exposure control that you can turn up either to maximum or to near maximum and that should help with bringing out enough stars. Prefer to turn up that gain control before you adjust the digital gain option in the star detection settings.

Cheers, Robin
woldsweather
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Re: Stars Not Detected & Bit Depth

#6

Post by woldsweather »

I have gain full on digital gain x4 and exposure 30s in order to capture any stars at all.
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