exposure times to plate solve
Stacking program, astrometric (plate) solver, fits file viewer
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han59
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I have been struggling to plate solve for months.I have a player one uranus C camera - pixel size 2.9.
I use it on 2 telescopes, Celestron 6se and Celestron cpc11. both with .63 reducer and sharpcap.
I have installed D80 database.
My images all solve at Astrometry.
My fov for the 6se shows 0.35 focal length 1029
My fov foe cpc11 shows 0.22 with focal length 1651
Most of my images will solve at the ASTAP site with further adjustment experiments.
Most FITS files solve in a second or so. Png sometimes takes adjustments, (sometimes downsample or fov etc ) but usually once adjusted solve fairly quick.
BUT thru sharpcap they very seldom solve and what works for 1 often does not work for the next.
My normal image settings are 4 or 8 seconds -- my gain is 350 or 400 when Sharpcap moves to the next object.
I read now in the chart that D80 database with those specs recommends 30 for 0.33 fov and 60 second exposures for 0.22 fov.
I have ask many questions on the Cloudy Night forums and had contact with Robin at Sharpcap. I have tried so many combinations to only achieve occasional success, but have never seen suggestion of these long exposure times. I have never even used an exposure with these alt az scopes past 12 or 16 seconds to experiment.
Am I using ASTAP / Sharpcap incorrectly ?
Thanks
Mike in Oregon
i ise astap via APT , astap likes short exposures for plate solving maybe try under 4 sec .
Dave
In the past months I have tried from 1 sec - 700 gain up to 20 seconds with lower gain.
I have tried wide variety of Focal Lengths.
One advise of one user with similar setup - tried Do Not Use for Focal Length.
Experimented with FOV - Down Sampling - Star Size .
Likely a thousand attempts across the last months.
I did have one really good night - Saved my Settings in ASTAP and Sharpcap and the next night near total fail.
I posted this thread yesterday before going out -
New issue last night - did CPWI Update 2.5.2 earlier and now scope will not track correctly or find GoTo's
But works great if I bypass CPWI. Cant access many of Sharpcaps features including Solve - Sync etc until I figure out whats up with that .
Thanks for looking in on my issue
Mike in Oregon
If its not One thing - its Two
Hi Mike,
Solving should be very reliable.
Did you enter in ShapCap a fixed focal length/fov?
Can you make a screenshot of your SharpCap settings?
Can you share images made with your 0.22 and 0.35 setup?
Han
Thank you for looking in on this.
I read from so many that its so easy and reliable.
Upfront - I'm relatively new to imaging. There are so many features in ASTAP - Sharpcap - that I do not understand how to use and often even what they do. But I will follow any instructions to provide what you need to help with my issue.
For the 6se I initially entered 965 FL . Because of my image train - Astometry says 1029. I tried both. Also upon advise from others I have tried all the way from 700 to 1200. AND upon advise from another that has great success with his 8se - I tried the * Do Not Use " option with about the same rate of occasional success.
For the 11 I started at 1750 - Astrometry solved at 1629. - Tried from 1500 - 2000.
Last night I only used the 11inch -- at 1629 and did get a number of solves.
The night before with the same settings - same sky - Nothing Solved.
I do not know of a FOV setting in Sharpcap ... ?? My sharpcap only has a field for Focal Length
My solving issues have been going on for months but I have had new issues with CPWI since the last update about a week ago. ( Time - Location settings all checked but GoTos are off even after a Starsense alignment . The mount continues to move even though tracking is on and I can hear it running. Never stops. Backlash is set well - scope move immediately without jump in all directions .
IF / When i can get a successful solve and sync - the mount stops moving and all GoTo's are back on track ).
Cloudy Nights members have suggested that I remove and reinstall ASCOM Drivers - and my Softwares in Order but have not had chance to complete that . I'm waiting for my son to help with it.
Control / Printscreen does not save an image of Sharpcap on my laptpp but I have attached camera shots of what I think will show what you need for settings. Let me know if you need other.
I have attached 2 images of my settings in sharpcap. ( sharpcap does not printscreen on my laptop for some reason ) - If you need more / other - just let me know
What type / format image files would you like to see.
Snapshot ?
Images saved ?
PNG ?
FITS ?
When I move from target to target - Sharpcap saves FITS Files - but I have no use for them other than an occasional manual plate solve at Astrometry or ASTAP websites.
I dont know how to do anything with them. I have looked at GIMP but ... wow - I'm even overwhelmed by some features of paint.
Hi Mike,
The focal length should be reasonable accurate. Can you
1- provide an image taken with your setup, either in FITS or PNG format.
You should be able to attach it to a post here. Secondly
2- A full copy of the log while your solving.
You can find it under Help. That should help to find your best focal length setting for solving and other issues.
I don think updating ASCOM will help.
3- What database did you install for ASTAP. I assume the D50 should sufficient.
4- What exposure time are you using for solving?
Cheers, Han
Just read you first post. The D80 is fine. For the image you can also provide the link to nova.astrometry.net. I can download them from there.
Han -
Sorry to be slow to re reply. But have positive news. Cloudy smoky skies have kept me from testing and I wanted to be sure before I replied.
Wednesday - 08-02-23
I deleted all my Astronomy Software and Started over .
I found a newer ASCOM and drivers - The New ASTAP 6.6SP1 - The New 2.5.2 CPWI - And New Edition of Sharpcap 4.1 XXXX.
I always had a feeling that something was awry in my set up. Whether its the Combination of New Versions - or removing the errant link in the chain , I may never know but , I should have done this long ago but had fear of messing up what I did have working.
After doing so, Everything worked for both Telescoipes. .
Items plate solved and sync'd except one - even with full moon and very smokey skies.
The one that did not - In live view I boosted the gain by 100 - and it solved and sync'd in Sharpcap.
Every night since has been cloudy and smokey until last night when I was able to get out an confirm with a repeat effort, that things really are turned around.
I still have so much to learn.
There are things in CPWI and Sharpcap that I have no idea of how to use and in some cases what to use them for .
The ASTAP site has so much more than I understand but I appreciate greatly your work and effort yet still taking the time to help users in the forums.
Thank You
MIKE in Oregon