SharpCap Forums

Some help please. I've been using SharpCap (Pro) for live stacking with my ZWO178MM and ETX125PE successfully but recently after the first image it is not pick up any stars to align with. It has plenty of star visible to pick from but none are being highlighted. Even objects that I have targeted before are no longer being tracked. I have reloaded SharpCap, tried various settings and reset the settings to default but still no luck. I have no changed my location. Thanks for any suggestion.

Hi,

two things to check...

1) use the 'reset all' button in the star detection settings to put default values back in case something has been changed
2) check that you are not usign a display stretch in either live stacking or the mini histogram that may be brightening the image enough for you to see the stars (this display stretch does not help the star detection). https://docs.sharpcap.co.uk/3.2/#!2!Min ... %20Stretch


If none of that helps then please post a screenshot showing the live stacking alignment tab and the image that is causing problems.

thanks,

Robin

Thanks I'll take a look.

Hi, I've tried the reset no luck. Also reinstalled SharpCap and ZWO drivers and still getting a problem. Also played around Digital Gain and Gain without luck. Here's a couple of images of the live stack page. As you can see I have plenty stars. Thanks for your help.

Hi,

nothing looks badly out of order there - the stars do seem a little out of focus, so you could consider making the following changes:

1) Increase max size to 32 pixels
2) Turn down the black level threshold to 20 to see if that helps
3) Turn up the digital gain to 2x to see if that helps

If you still have no luck, please capture a single frame (come out of live stacking and press the 'Snapshot' button). If you can then share that frame image here (if it is too large, upload it to somewhere like dropbox, one drive, google drive and share a link). I will then have a look at the image direct from the camera and see if I can work out what is going on.

thanks,

Robin

Robin, thanks for your help and suggestions, I'll give it a try and let you know how I get on. Thanks again, John

Robin Hi, Thanks for your help, I've tried the suggestions from your last last reply using various exposures and gains. Still no luck. I've attach a link to an image taken last night together with the camera information. It would be appreciation if you could take a look and any suggestion would be appreciated. ETX125PE, ZWO178MM, 0.6x focal reducer, Bortle 6 sky and 10 day old moon.

https://drive.google.com/file/d/1POVxGj ... sp=sharing

[ZWO ASI178MM]
Pan=0
Tilt=0
Output Format=FITS files (*.fits)
Binning=1
Capture Area=3096x2080
Colour Space=MONO16
Temperature=16.2
Hardware Binning=Off
High Speed Mode=Off
Turbo USB=60
Flip=None
Frame Rate Limit=Maximum
Gain=485
Exposure=2
Timestamp Frames=Off
Brightness=60
Auto Exp Max Gain=255
Auto Exp Max Exp M S=30000
Auto Exp Target Brightness=114
Banding Threshold=35
Banding Suppression=0
Apply Flat=None
Subtract Dark=None
#Black Point
Display Black Point=0
#MidTone Point
Display MidTone Point=0.5
#White Point
Display White Point=1
Notes=
TimeStamp=2021-04-22T21:23:20.8092949Z
SharpCapVersion=3.2.6482.0

Hi,

with that image I get good star detection with the parameters shown below
I think the key is turning up the noise reduction - it's quite a noisy image, so the amount of noise needs to be suppressed somewhat to allow the star detection to work well. An alternative would be to increase the exposure and reduce the gain, which would also reduce the noise levels.

cheers,

Robin

Thanks again Robin for your help. I'll give it another go but at the moment the Moon is dominate. Good to here that you are getting star detection with the image so the image must be good. Thanks again.