Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 11/19/2012 - 23:58
It appears that no matter what value I give with the "resolution" parameter I get a rather small 72 dpi image. An example URL is http://www.aavso.org/vsp/chart?name=v452+cas&charttitle=v452+cas&fov=24&resolution=120&maglimit=18&north=up&east=left&forcelines=on&othervars=all. When I click on the resulting chart I get 600x750 chart. I get the same resolution chart when I substitute 150 or 75, or seemingly any other value for resolution.
Thanks,
Shawn (DKS)
I don't think that the intent behind the www.aavso.org/vsp/chart URL is to produce high resolution charts to begin with, especially since the output is an HTML page rather than just a .PNG image.
I would use http://www.aavso.org/cgi-bin/vsp.pl to generate charts of various resolutions. I think it is also the only URL that the VSP API documentation mentions (could be wrong though).
--- edited ---
... and I was wrong :). The "www.aavso.org/vsp/chart" URL is indeed mentioned in the API. Until its functionality is fixed, my suggestion is to stick to "http://www.aavso.org/cgi-bin/vsp.pl".
Thanks for the suggestion - I tried it out and using the "cgi-bin" path does give a chart of the requested size. However, I generally need both the chart (for matching stars to my images) and the CCD photometry table to reduce the images. I'll send a note directly to the AAVSO maillist since they may not be aware of the bug. In the meantime I can make two web requests using the "cgi-bin" path: one to get just the chart and one with "ccdtable=on" to get just the photometry data.
Shawn
Yeah, I guess. I didn't try to get the CCD table, so I'm not sure if they re-send the map. If they do, then the two calls will end up transfering more data than actually needed. In that case, then yes, I would think of it as a bug.