Andy Wilson

Forum Replies Created

Viewing 20 posts - 301 through 320 (of 431 total)
  • Author
    Posts
  • in reply to: 2017 eaw #578218
    Andy Wilson
    Keymaster

    Hi Paul,

    That is a very useful webpage, thanks for sharing.

    Though I usually do spectroscopy, this is not the right kind of target for my setup. So I’m hoping to take a look at it though my Dobsonian instead.

    Cheers,

    Andy

    in reply to: Mass & precession of the Disk in zeta Tau #578216
    Andy Wilson
    Keymaster

    Hi Ernst,

    An interesting paper and a good demonstration of what can be achieved with the high resolution spectrographs that are now available to the amateur community.

    Best wishes,

    Andy

    in reply to: Sporadic 3rd May 2017 01:25UT #578192
    Andy Wilson
    Keymaster

    Hi Michael,

    That is a very thorough analysis! Hopefully Bill or someone with knowledge of meteor spectroscopy will comment on your spectrum. It certainly looks good but I cannot comment on the line identification.

    Cheers,

    Andy

    in reply to: Dr Bill Ward #578187
    Andy Wilson
    Keymaster

    Congratulations Bill! A fantastic achievement!

    Andy

    in reply to: Lyrids 2017 #578176
    Andy Wilson
    Keymaster

    Hi Bill,

    Those are great spectra of the Lyrids! There is a whole wealth of spectral lines. Is it difficult to identify them all or do you have resources that allow you to identify all or the majority of the lines?

    Cheers,

    Andy

    in reply to: Spectra database and IRAF “multispec” format #578175
    Andy Wilson
    Keymaster

    Robin,

    That is a good point about ensuring that amateur software should be able to read the files.

    Andrew,

    Glad to hear you are making progress. Python with astropy are fantastic for programming with fits files. So far I’ve only been using them on a Mac, but I must get around to trying them out on Windows.

    Cheers,

    Andy

    in reply to: Spectra database and IRAF “multispec” format #578172
    Andy Wilson
    Keymaster

    Give me a shout if you get stuck. It would be nice to have a single fits file format for the multiple orders in Echelle spectra, but I suspect agreeing that amongst the community would be no small task.

    Andy

    in reply to: Spectra database and IRAF “multispec” format #578170
    Andy Wilson
    Keymaster

    Hi Andrew,

    You are correct in your assumption that the BAA Spectroscopy Database does not support IRAF multispec format at this time. However, it is possible to build in support. The big question is how long it would take me to build, noting I already have some outstanding development work for the VSS Database.

    It may take until the second half of May or June to take a proper look at the file format. Then I can assess whether a ‘quick’ change is possible.

    Note of course that the other header fields would need to be BeSS compliant. If this is going to be a problem then it won’t be worth going down the route of building IRAF multispec compatibility.

    Best wishes,

    Andy, BAA Spectroscopy Database Manager

    in reply to: Our 100th BAA Member’s Page #578125
    Andy Wilson
    Keymaster

    Hi Marc,

    It is great to see how spectroscopy has grown at the BAA over the past couple of years. The subject being one of the main areas of discussion on the forum, with advice being given to help members get started, as well as some fantastic results being shared.

    We also have a spectroscopy database where members can upload their 1D fits format files. Noting a separate login is needed as it runs on different software to the main BAA webpages.

    https://britastro.org/specdb/

    I think Ernst’s proposal for a VV Cep campaign is great. Though I am aware that Ernst has a long running campaign on VV Cep and so I am not sure if it is appropriate to think of it as a BAA campaign. There is a separate thread that Ernst has started on the campaign so probably best to post any questions there so that there is a single place to access the information.

    Sadly for me a bank holiday weekend when I actually have time to do some spectroscopy and the forecast is for wall to wall cloud! Oh well, as a UK based amateur astronomer I learned along time ago that large reserves of patience are essential 😉

    Best wishes,

    Andy

    in reply to: Radius Estimation of VV Cep´s disk #578121
    Andy Wilson
    Keymaster

    Hi Ernst,

    Thanks for the information which is useful to know. I’ll try to get an observing session in soon on VV Cep. If that doesn’t work out then I may use my limited observing time on Be stars which are well suited to an occasional spectrum when time allows.

    Best wishes,

    Andy

    in reply to: Our 100th BAA Member’s Page #578120
    Andy Wilson
    Keymaster

    Welcome to the BAA Marc and great to have another spectroscopist! As you have no doubt seen, the spectroscopy forum has been very active.

    Andy

    in reply to: Radius Estimation of VV Cep´s disk #578114
    Andy Wilson
    Keymaster

    That is an interesting campaign Ernst.

    I’d like to get involved if I can, though my own observing has been significantly curtailed this year due to other commitments. If things settle down over the Spring/Summer then I’ll add it to my target list so that I can contribute.

    Best wishes,

    Andy

    in reply to: Winchester Weekend 2017 #578113
    Andy Wilson
    Keymaster

    I concur that it was a great weekend, many thanks to Ann Davies, Alan Dowdell, Roger Pickard, and everyone else who were involved in the organisation.

    Tough to pick out the best speaker, but I was very impressed by Prof Giles Hammond stepping in for the Gravitational Waves talk, you really could not tell that he stepped in for someone else. I also enjoyed Dr Poshak Gandhi’s talk on black holes as he engaged with the audience and did not simply use PowerPoint. Lots of other great talks but I won’t list them all.

    Andy

    in reply to: New types of object added to the spectroscopy database #578112
    Andy Wilson
    Keymaster

    Hi Tony,

    There is no need to re-classify your objects. I did this as part of the checks that I run, though if you do ever spot anything that should be changed then just let me know.

    Just look for the new subtypes when uploading spectra, and also let me know if you need any new ones setting up.

    Cheers,

    Andy

    in reply to: I am new here #578096
    Andy Wilson
    Keymaster

    Hi Ernst,

    Welcome to the BAA forum.

    Best wishes,

    Andy

    in reply to: ALPY off axis guider #578076
    Andy Wilson
    Keymaster

    Hi Nick,

    I think you mean the ALPY guide module rather than a separate off axis guider. Though that doesn’t really matter for this discussion.

    I assume that you are using the ATIK Titan for guiding. When you say no response, does it take an image which is blank, or can you not even get it to take any image with the Titan? I take it you are pointing your setup at the blank daytime sky for the solar spectrum. Note it should not be pointed at the Sun for a solar spectrum as the reflected light from the sky is easily bright enough. Pointing directly at the Sun would probably fry the guide camera and might do some other damage.

    Otherwise you could try other software rather than MaxIm DL for guiding. Though I use MaxIm DL to acquire my spectrum images, I switched to the free PHD2 for guiding as I found it far superior.

    http://openphdguiding.org/

    Best wishes,

    Andy

    in reply to: A tale of inconsistently catalogued spectral type #578040
    Andy Wilson
    Keymaster

    Hi Kevin,

    That is a nice looking spectrum and an interesting story to go with it. A good example that you can get unexpected results with spectroscopy and by digging around in the literature lots of useful and interesting information can be found.

    You are getting some great results with your ALPY.

    Cheers,

    Andy

    in reply to: Relative Flux Calibration #578039
    Andy Wilson
    Keymaster

    Hi Tony,

    In ISIS (and other amateur packages) this is usually taken account for in the single combined step for instrument and atmospheric response correction.

    The approach is take a spectrum of a standard A or B type star that has a spectrum in the Miles or similar database, and that it is at a similar altitude to your target. You use your spectrum along with the one from the Miles database to calculate a combined instrumental and atmospheric response correction. Where this won’t work is if you try to observe a target at a significantly different altitude, or if the sky conditions change. In that case you would need to take a fresh spectrum of an appropriate A or B type star.

    When removing individual atmospheric telluric lines then it will be necessary to take a more sophisticated approach. ISIS has another tool which can be used for that but often this step is not needed for the target spectra. I also find this only approximately works rather than giving a really good telluric removal.

    Cheers,

    Andy

    in reply to: NGC 2903 #577996
    Andy Wilson
    Keymaster

    Hi Alun,

    As David says, this spectrum would be a welcome addition the BAA Spectroscopy Database, and expect you have others.

    The spectra need to be in 1D fits format with the BeSS fields populated. I know BASS can produce this format, so just let me know if you need any pointers. Otherwise just email me a sample 1D fits file when you are ready and I will use that to set you up in the database. I don’t put my personal email address online, but you can email me at vssdbm <at> britastro.org

    Cheers,

    Andy

    in reply to: NGC 2903 #577993
    Andy Wilson
    Keymaster

    That is a nice image for 400 seconds. I will be interested to hear how you get on with that project.

    Cheers,

    Andy

Viewing 20 posts - 301 through 320 (of 431 total)