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SeqPlot 4.0 release

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BSJ's picture
SeqPlot 4.0 release

A new version of SeqPlot has just been released. The biggest change in this version is really behind the scenes and has to do with how the program acquires data from our database but you will notice a few smaller improvements as well.

If you are using the Java Web Start version (i.e. if you launch SeqPlot using the file called seqplot.jnlp) then you shouldn't have to do a thing and next time you use it, you will automatically get the new version. You will know its the new version if it says Seqplot 4.0 in the title bar.

If you are running from the local version (i.e. if you downloaded from here:, you will have to download it again. All older versions will stop working very soon. Actually, I would highly recommend you try the new Java Web Start version which you can get by clicking the "Download SeqPlot Now" button on the seqplot webpage. Even if you had trouble with it in the past, I think you may find that because of the way that the program now fetches data from the database, it should work better -- even for those of you with slow internet connections.

Many thanks to volunteer Patrick Wils for making this improvement possible!

As always, please let me know if you have any problems or questions.

-Sara  (sara [at]

spp's picture
"upload the output text file to HQ"

"that means sending it to Arne so that he can batch upload it into VSD."

Hi Sara,

I just learned about seqplot from a post by Ken Menzies in the VPhot forum.

Using Velimir's instructions in the VPhot forum, I recently made my first comp star sequence with the tools available in VPhot using APASS stars via the APASS download tool.  The first time through I'd have to say I found the whole process a bit tedious, but it probably would go much faster the next time.  At the end of the process the new sequence (twelve comps and one check star) was immediately available for use in VPhot.

I just read through the seqplot instruction page (but I haven't yet tried using seqplot).  Seqplot sounds a lot simplier and faster, but at the end it seems there is another step, out of the users control, before the new sequence can be used.  Am I interpreting this correctly?




They Have Different Formats

The output for SEQPLOT is a different format than the input for VPHOT sequence files.

Here a link to a description of the SEQPLOT output:

The VPHOT Sequence file input format can be found under the "Sequences" section under the "Admin" tab in VPHOT.  Click on "Help" and then click on the link for the file format.

I have a small bit of C code to make VPHOT sequences out of SEQPLOT output that I am willing to share with you.  Contact me if you want it.  

I get the impression that HQ doesn't want that code just out there because there are concerns about making it easy for people to dump all of APASS unsorted into VPHOT sequences.  In my experience the work the Sequence Team does is very quick and of a higher quality than most of us can do ourselves (they have A LOT of practice).  So you are best served by requesting a sequence following the instructions at the following link rather than rolling your own:

spp's picture
VPhot and seqplot different formats

I can certainly understand a concern about making it too easy for observers to make their own sequences or mess with the AAVSO sequences.  Of course, the best way to prevent this is to have a responsive sequence team that produces good sequences in very short order whenever observers ask for them.  Based on my experience with requests for the sequence team this is exactly what we have.  When doing photometry on VSX variables to be reported to the AAVSO database, there is really no reason to make your own sequences (except, as in my case, one time primarily out of curiosity).

I think people are likely to want to use so powerful a tool as VPhot for some of their own projects which may not involve VSX stars or reporting their measurements to the AAVSO database.  For example VPhot  would seem to be an ideal tool for doing asteroid photometry by making a sequence of APASS stars which follows the predicted path of the asteroid.   Wouldn't seqplot make that sort of project a lot easier to do as opposed to using the sequence tools in VPhot?  

Perhaps that  "bit of C code", or something similar, could be incorporated into seqplot to make this process easier.  Is there a way to make seqplot useable for non-AAVSO database projects while protecting the integrity of the AAVSO sequences used for reporting to the AAVSO database?


Roger Pieri
Sequence Guidelines

Hello Sara,

Within the seqplot page there is a link to the document "Sequence Creation and Revision Guidelines". I am interested in for specific needs. I often use VSP but I have cases I set a specific "ensemble" to be used with my own photometry software. I am just curious to compare what I do with those guidelines. But the link hereabove requires a permission and I can't access it. Is it a way to get this document ? 


Clear Skies !


BSJ's picture
Sequence Guidelines

Hi Roger,

This page is now available without login: Sequence Creation and Revision Guidelines.

I hope you find it useful.

Best regards, Sara

pox's picture
So, is there now a facility

So, is there now a facility for allowing users to produce a 'telescopic' view (i.e., S at the top etc) for us Neanderthals who observe visually?

BSJ's picture

Hi All,

Thank you all for your comments and suggestions for Seqplot. Please remember that although Seqplot is publically available, the program was really developed for use by the Sequence Team for their specific purposes and hence has never been particularly user-friendly or flexible.

The other thing I wish to re-iterate is that we have a wonderfully responsive and experienced team of volunteers who will create new sequences or expand old ones - usually with a less than 24-hour turnaround time. All you have to do is fill out a simple form. The instructions are here:

The advantage of having the Sequence Team create new sequences is that what they come up with will be immediately incorporated into the chart plotter and will be available to other observers. Of course, when everyone is using the same comparison stars and the same magnitude values, the data are always better.

Having said that, I can definitely see Phil's point about Seqplot being useful for other applications such as asteroid work. Also it would be nice if the orientation of the field of view could be changed as Mike suggests. However, at this point, much as I would like to, I just don't have time to work on such nice-to-have revisions or create other output file options with the intention of re-purposing this tool. I have made a note of your suggestions in any case, and if the opportunity presents itself, will certainly consider it. Alternatively, if someone out these knows Java and would like to work with the code to revise it, I would be happy to share.

Roger, to answer your question about the documentation, I will have to check with the Sequence Team as I don't have access to that page either!


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