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Is this normal behavior?

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Ed Wiley_WEY
Ed Wiley_WEY's picture
Is this normal behavior?

I am a long time user of VPhot, but not experienced in using a single comp and check. When I perform a time series on an EB with a single comp and check and try to plot the comp, I get all images "undetected" (lots of red on the screen) and no comp plot. I know the comp is detected on single images. SNR ofr all well over SNR=100. I have tried several different combinations of one comp and one check, same result.

Motivation for the single comp and check: using TransformApplier. Ensemble analysis of the same variable does not present this problem. I tried two different browsers, same result.

Is this normal for single comp and single check analysis?

Can share screen shots if needed.

Thanks, Ed

MZK
MZK's picture
Ignore lack of comp plot

Hi Ed:

I think I know what you have described. Pablo L: saw same thing with a bright comp in his TS.

However, ignore the lack of a comp plot and save the TS report anyway. I "think" you will find that the report will show all expected data?

Should not happen but see if you get the desired report output?  

Ken

pablotwa
pablotwa's picture
Same problem I had..which wasn't a problem after all.

Hi Ed

Same problem I had but Ken helped me by showing me that the AAVSO report did report the comp values correctly..an idiosyncrasy of vphot with a single comp I guess.

Pablo

SGEO
SGEO's picture
VPhot question

Ed,

Please share with me more details or screen shots. I'd like to get to the bottom of this. Send the info to SGEO@GASilvis.net. We'll share with the forum our results.

George

 

SGEO
SGEO's picture
VPhot yes, its normal

If there is a single comp star in a time series there is no plot of the comp star data. How could there be since any magnitude data displayed is relative to the comp star!  When you have an ensemble you can get a plots of the components of the ensemble, I assume against the ensemble. You might do this to make sure you haven't picked up a variable into your ensemble. If you are using a single comp then it should be a certified compstar from our VSD and you needn't worry.

That VPhot is offering to show a plot and then alarming you with warnings it its bad; I'll make a note that it should not do that!

George

 

MZK
MZK's picture
TS comp plot error

George:

This is a relatively new problem. If one uses a single comp and check as opposed to multiple comps (ensemble) for a time series, the Comp Stars Light Curve plot (upper right group of plots) shows no comps! The ensemble TS shows this graph. See attached.

Ken

SGEO
SGEO's picture
VPhot single comp

As I point out above, there is no comp plot because there is no reference in this case. Perfectly normal.

Ed Wiley_WEY
Ed Wiley_WEY's picture
VPhot SIngle Comp, Thanks George

Thanks, George, that clears it up for the graph. Someone might think about putting this information in the VPhot manual if it is not already there.

Ed

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