SharpCap Forums

version 4.0 using 8 second exposures plate solves first time every time.

Version 4.1 either comes up with a message cannot plate solve or complains that too few stars present and asks for more gain or exposure time.
setting the exposure to 30 seconds and the gain 500 makes no difference.

The camera is an ASI 585 pro and the telescope is a 10 inch RC
In 4.1 I have downloaded the files for the 0.5 and have tried all kinds of changes in the config window but no success.

To get round this I first load up 4.0 and plate solve then close and open 4.1 for the stacking of images etc.

Its as if the image is not being stretched before star detection takes place but that is just a guess on my part.

The section from the log is attached
Trev

Hello,

You can first check the same Plate Solve software with both SharpCap version.
The SharpCap 4.0 uses only extern Plate solve software.

If the same extern Plate Solve software gives the same results with 4.0 and 4.1, then you can have a look with the internal Plate Solve of SharpCap with the 4.1 version.

You say that you have the files for the 0.5 ... I guess that the 0.5° field is integrated with SharpCap installation file.
The additional 0.25° has to be downloaded manually before the first use.
Do you have now downloaded the additional 0.25° files ?

The ASI 585 has a small chip (6.26 x 11.13 mm) ... 10" RC has most of time FD = 8 ... so 2032 mm with small chip ... that is a challenge.
You will have 0.18° x 0.31°... that is at the edge of the "0.25°" field. So you need to download the additional files.

Regards,
Jean-Francois

Yes the files for the 0.25 have been downloaded. I will look again to see what the differences are between 4.0 and 4.1.

Any clues in the log file that might point to a solution? I am aware that the camera has a small chip but it never fails to plate solve and sync with the settings in 4.0 so I figure if 4.0 can do it then 4.1 should as well.

Trev

Hi Trev,

in the older version you must have been using an external plate solver (Astap, Astrotortilla, etc). You have got 4.1 configured to use SharpCap's built in plate solver, but it looks from the log like you have a field of view of 0.32x0.18 degrees from a focal length of 2000mm. This field of view is below the 0.25x0.25 minimum that the built in plate solver is designed for (even with the extra star database), so results are likely to be patchy at best.

I would suggest adjusting the plate solving engine setting in 4.1 back to use the one you were using in 4.0 and see if that helps.

cheers,

Robin

Thanks for the reply and you are correct in that I had 4.0 using the cygwin_ansvr where as the 4.1 was set to Sharpcaps own plate solving engine.

I have changed 4.1 to match the 4.0 settings so just need a clear night to test I think what fooled me was the self test in 4.1 reporting all was good.

Either way I will confirm one way or another to close this report out.

By the way have you seen the YouTube vids praising the plate solve push to facility for non goto mounts. looks like its been well received.

Regards
Trev

Hi Trev,

it's supposed to keep the existing plate solver when you upgrade as long as the selected one is actually installed on the machine. If you upgrade and have ansvr selected before the upgrade, but ansvr isn't there, it's supposed to change to SharpSolve. Maybe that's not quite working right all the time.

The 'Test' button in the plate solve settings just feeds a known image (of the stars around the north celestial pole) to the selected plate solver and checks it works and gives the right results - it's really designed to check that programs like Astap or Ansvr are installed correctly and have index files. It can't work out for you whether your choice of plate solver or plate solve settings will work with your particular telescope/camera/camera settings combination.


cheers,

Robin

tried again last night but still no joy.
New message XYLIST Field appears along with try more gain and exposure no stars found.

Closing 4.1 and opening 4.0 with 8 seconds exposure solves and syncs first time.

Anything I can do to help resolve this?

I created an export settings file from my 4.0 plate solve settings and tried to import into 4.1.

all it did was set 4.1 to the default Sharpcap search engine and none of the settings in 4.1 now match my 4.0

Post this test I have re-entered the settings manually so that they match and pictures taken

These are my settings for plate solve in 4.0 and 4.1

Hi,

the settings look pretty much fine, so it's a bit odd. The message about XYLIST ties in with not enough stars detected.

I would suggest getting it working in 4.0, then use snapshot to save a frame with the same settings. Try the same in 4.1, also snapshot - now we have two images saved (one worked, one didn't) that we can compare to make sure there is no significant difference in the brightness level/star visibility going in to the plate solve. I'd be happy to look at those images if you want, and also to look at the SharpCap logs from the two tests to see if I can spot what is going wrong.

cheers,

Robin