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EE Cep Eclipse Campaign July/Aug 2014

aquillen's picture
aquillen
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Joined: 2014-05-18

There is a nice EE Cep campaign website for the August 2014 eclipse now up!

https://sites.google.com/site/eecep2014campaign/

Right now there is not much photometric coverage from the western hemisphere.  And near infrared observations before, during and after eclipse would be really valued. Absorption lines from shell material could be detected months before eclipse (and that's right now!). 

Not mentioned on the web site is the prediction (by Galan
 et al. 2012's) that the 2014 eclipse should be a deep one compared to the last two.  Two groups will be trying to see if it is possible to detect molecules in absorption during eclipse.

EE Cep - Alert Notice 502
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weo
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Joined: 2010-03-25

AAVSO Alert Notice 502 has been posted, requesting observations of the Be star EE Cep beginning now in order to observe its upcoming eclipse. Please see the Alert Notice for details.

Good observing,

Elizabeth Waagen, AAVSO HQ

Untransformed observations
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potterrb
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Joined: 2010-08-06

I would be happy to contribute to the observations of EE Cep throughout the eclipse, but am not experienced at doing transformations.  I am using a scope on iTelescope.net, please let me know if untransformed observations are still of value, or if not, I would love to speak with someone about what I need to do to calculate transformation coefficients for the scope and location that I am using.

Thanks -- Brian

Untransformed Observations
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HBB
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Joined: 2010-07-24

Brian,

If you look at the observations, the majority are going to be untransformed.  So you can submit untransformed observations.  But this would be a good time to obtain transformation coefficients.  Fortunately,  the AAVSO is working on two programs now that will make it easier to obtain your transformation coefficients and apply them to your observations.  The two programs are called Photometry Transformation Generation Program and Transform Applier.  The Photometry Transformation Generation Program requires you to image standard stars in M67 or NGC 7790.  Unfortunately at this time of year M67 is not available but NGC 7790 is available.  It requires obtaining the instrumental magnitudes of some stars from one of those clusters and the program will generate your color transformation coefficients.  You then place those coefficients into the Transform Applier program then open a file of observations that you obtained from EE Cep for example.  The Transform Applier program will then generate a report of the transformed magnitudes of your observations.  You can get started and download the programs by going to this page:

http://www.aavso.org/transforms-everything-you-need-transform-your-ccd-o...

Barbara 

transf. coeff. - itelescope
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Raymond
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Joined: 2013-05-04

Hi Brian

You can find a list of the transformation coeff. on the pages of some telescopes, such as iT11 and iT21. But I'm nor sure, how to use them in VPhot. Maybe it's very simple ....?

Raymond

Untransformed observations
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SGEO
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Joined: 2010-11-16

You might inquire if the iTelescope system you are using already has transform coefficients available. These characterize the scope and I would think a commercial scope would have them available along with extinction coeffcients for the site. Worth asking.

With coeffcients in hand then all you need is your observations worked up for submission to WebObs. The TransformApplier takes these to things as input to create a new file ready to submit to WebObs with the transformed data.

George

Transforming EE Cep observations
potterrb's picture
potterrb
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Joined: 2010-08-06

Thanks all for the responses, and Raymond I am using T21, didn't realize they posted coefficients on the telescope page...excellent!

EE Cep eclipse and comparison stars
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weo
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Joined: 2010-03-25

The eclipse of EE Cep appears to be gradually getting underway.

Also, if you use COUSINS R and I filters, be sure to use COUSINS R and I magnitudes to reduce your data!! Do not use the Johnson R and I magnitudes given by Galin et al. The Cousins values are in the AAVSO Photometry table for EE Cep.

If you have already submitted R and I data, please check your files to be sure you used matching filters and comparison magnitudes. If you did not, please delete your observations, re-reduce them correctly, and resubmit them. If you need help with this, please contact us.

Please see AAVSO Special Notice #387.

Many thanks, and good observing!

Elizabeth Waagen, AAVSO HQ

AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484