[Aavso-photometry] Reality Check - Basic Concepts

[arne]

Now your question makes sense.  I was at first thinking that you were
worried about the light curve scatter, which looked pretty normal to me.
As Aaron says, we did have a chart with comparison stars available within
a few days of the discovery; this last chart is just a revision.

The two ways you can handle images before a good sequence is announced:
(1) hold onto your data until the sequence is available, then submit the
backlog.
(2) pick some nearby star, preferably one with existing photometry from
Tycho2 or ASAS, and use it as your comp star.  Report the magnitude you
used for that comp in the comments/notes section of your report.  Then,
when better photometry is available, either the researcher can adjust
the photometry, or you can go back and modify your original report.
Arne

David Trowbridge wrote:
> But I thought there were no comparison stars in the vacinity of this Nova
> until just a week or so ago when chart 1804-18 was released. Am I wrong? The
> light curve goes back to before the chart, doesn't it?
> 
> David
> 
> -----Original Message-----
> From: Michael Koppelman [mailto:lolife at bitstream.net] 
> Sent: Wednesday, June 13, 2007 5:48 PM
> To: David Trowbridge
> Cc: AAVSO Photometry; Rebecca Jensen-Clem
> Subject: Re: [Aavso-photometry] Reality Check - Basic Concepts
> 
> For this question I would say, no. The common case is people doing  
> differential photometry against comparison stars without transforming  
> the observations.
> 
> For people just getting started (and, in fact, people who have been  
> doing this for a long time) it is by far easier to go differential  
> and untransformed. With well-chosen comparison stars, the error  
> introduced by not transforming is quite minor.
> 
> M.
> http://www.lolife.com/astronomy/
> 
> 
> On Jun 13, 2007, at 5:55 PM, David Trowbridge wrote:
> 
> 
>>Question #1: In general, do the data points in this light curve  
>>represent
>>the results of observers who have been doing all-sky photometry and  
>>using
>>standards such as Landolt, M67, etc?
>