Scale high/low problem

36 views
Skip to first unread message

Paul Evangelopoulos

unread,
Jun 8, 2025, 7:13:35 AMJun 8
to astrometry
Hello,

I am having a problem solving an image through my c# app using elendil library.

When submitting the image through the web api it is solved.

(M41 open cluster)

https://nova.astrometry.net/user_images/12794853#annotated  

When calculating scale low/high and submitted through my app I receive "failure solving image"

The image is 450px X 450px and the field is 3 degrees x 3 degrees  

Below are the settings I use.

I use tolerance 0.1 in calculating scale high/low

publicly_visible = software.elendil.AstrometryNet.Enum.Visibility.n,                                
Scale_units = ScaleUnits.arcsecperpix,
scale_type = ScaleType.ul,
scale_lower = scaleLow, // 21.6 calculated by my app
scale_upper = scaleHigh, // 26.4 calculated by my app                            
radius = radius, // 7.8 calculated by my app
center_ra = Ra,
center_dec = Dec,

As far as I know the numbers are correct. I used various values for tolerance but no result.

Please give me your suggestions if you think that I can change some values.

Thanks

Paul  

Dustin Lang

unread,
Jun 9, 2025, 8:57:11 AMJun 9
to Paul Evangelopoulos, astrometry
Hi,

I notice that "Scale_units" starts with a big S where the rest of your args start with lower-case letters.  Any chance something is going wrong in your call to the API?

If you can send a URL for a submission sent in via the API, that will be worth looking at and probably indicate what is going wrong.

Oh, the other thing is the web site by default uses downsample=2, but the API uses downsample=1 by default.

cheers,
dustin



--
You received this message because you are subscribed to the Google Groups "astrometry" group.
To unsubscribe from this group and stop receiving emails from it, send an email to astrometry+...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/astrometry/f3c69523-5495-4365-85d7-4e4bae223de4n%40googlegroups.com.

Paul Evangelopoulos

unread,
Jun 9, 2025, 9:24:42 AMJun 9
to astrometry
Hello,

Scale_units is correct in the implementation of elendil

I added this line

downsample_factor = 1

For this job


I get error 403 Forbidden by server

Paul

Dustin Lang

unread,
Jun 9, 2025, 3:08:45 PMJun 9
to Paul Evangelopoulos, astrometry
Hi,

Here's the status page for that submission:


Something has gone wrong with your specification of the scale units, because it says "Scale Units: width of the field (in degrees)".

Also, if you want to reproduce what the browser-based submission does, you want downsample=2.

cheers,
dustin



Paul Evangelopoulos

unread,
Jun 9, 2025, 3:54:33 PMJun 9
to astrometry
Hi,

Thank you for your remarks. There was a typo in the library. 

I changed the definition of Scale_units to scale_units. Just a letter caused a big headache. 

It seems that the server defaulted to "width of the field (in degrees)".

Now it works without errors.

Paul
Reply all
Reply to author
Forward
0 new messages