In recent days - more or less when the new web site was brought online - VSP fails to show comp stars. For example, VSP does not show comp stars for SU Cep. Similarly, when I ask for a Photometry Table, it throws the error “No comparison stars found in this field.” Older VSP charts of SU Cep in my possession do show comp stars, so I’m not sure what’s going on. And this has happened with a half dozen other variables (mostly eclipsing binaries) in recent days. I’m running Chrome on a Macintosh.
Several of the functions on the web site fail the first time thru. I clean up browser cache and cookies often… Sorry… I have this leave no trace hiking/camping on the internet thing. 
For example I just ran SU Cep “d” scale in firefox and it gave a vague browser or cookie error first time thru. Second time thru worked fine. On the “d” scale chart there are only three comps, table is produced ok.
It appears to be a do, do while, while do loop initialization issue or a local cookie missing first time thru or similar.
Still having problems?
Hi Andy,
I see three comp stars around SU Cep (99, 104 and 105).
Check the chart fields, maybe the limting magnitude is wrong or something.
I tried a C-scale chart.
Sebastian
Hi Sebastian, thank you and DEY for trouble-shooting. I did succeed in downloading the chart using Lesve Photometry on my Macintosh running Parallels. It was a Chrome browser on the Macintosh side that gave the difficulty. With the downloaded chart & comp stars, I successfully observed SU Cep last night. Best, Andy