Can someone explain why the photometry tool in MW gives a delta mag value that is different (better) from the one of the light curve, on the same frame plot?
I suppose it's due to the fact that the light curve takes into account the V-C values and not only V but how to be sure, thus, that delta mag is good enough for the spotted star?
do you have a screenshot? I am not shure what exactly you mean...?
So far: Photometry is (more) stable if a compare star is used, to determine the magnitude. And a check star, which proves that the compare is constant! (C-K plots should be a straight line...) This is resultin always in a V-C plot. Normally Muniwin give you these V-C plots everytime! if you take the var, comp, chk -stars (So I do not get your question guite..?)
Under object properties: one can plot: SKY, FWHM, Apparent MAG -> this apparent MAG is some instrumentiall mag (without - C) under very good seeing conditions, the graph could almost look the same like a V-C, but it will be never as good as a V-C plot. (I use this to determine if the seeing was good..or not)
Under Munifind: one can do datamining an look for other stars. If you choos this plot, there is onle a V because the green comp star, does not have a blue check star in this plot... (do you had this plot in mind?) But you wount upload this only V data to the AID..
Muniwin is cool for beginners. Its not too complex, but one can get very far. At the BAV e.g. 50% of the people might be using Muniwin (-:
thank you for your response. You say that "this apparent MAG is some instrumentiall mag (without - C) "
But how muniwin can compute a mag without giving a comp star to calibrate the ADU ? Does it simply do "-2.5*log (ADU)" ? How reliable this value is ?
EDIT : My bad, I found that instrumental magnitude is always without comp. OK
But, yet, I have another question. When you select a star under Photo Tools in Muniwin (without any comp or check), Muniwin gives you a positive magnitude (=> not the instrumental one). How can the software compute such a mag without any comp or check ?
For those who are interested in the answer, I contacted the main developper of muniwin who gave me the reason : A constant is added to the instrumental magnitude so as to calibrate it.
As we work differentially between variable, comp and checks, this constant has no effect, and this is why the magnitude is positive, BUT it is an instrumental mag