Photometry measure all annotadet -> also for own annotations ?

[Thomas Rudolph]

Hello Han,

for stars with small amplitude variation it would be desirable to have more comparison stars for further processing. The function mentioned above would be ideal if you could use your own annotations (created with the mouse context menu item). However, this does not seem to be possible. Is there a possibility or could you please modify the program so that you can also measure a number of your own comparison stars, about 6 maybe ?

CS
Thomas

P.S. I found an easy solution already exxisting in ASTAP.
At least I hope that I have understood it correctly: 'Annotate variable stars' and 'Measure all annotated' uses the variable_stars_xxx.csv files in the ASTAP directory, and you could simply add the desired comparison stars there.

[Thomas Rudolph]

Hello Han,

please a last question regarding this issue:
The variable_stars_xx.csv file fprmat is

RA[0..864000], DEC[-324000..324000], label

but, if I use any example variable star and try to do the conversion with its J2000, then I always have a small deviation of the value of approx. 2 in RA.
DEC, on the other hand, is exactly correct. Do you have a hint what the reason could be?

CS
Thomas

[han.k]

Hi Thomas,

I will look into an option manual selecting an ensemble.

Attached a small part of my database spreadsheet. I use it to calculate the integers from the RA, DEC positions. Does this solve the problem?

Cheers, Han

[Thomas Rudolph]

Hi Han,

many thanks for your help. Sorry but I must still be doing something wrong:

Example:
V0451 DRA
(SIMBAD: 11 24 25.3496382768 +77 42 15.624315072)

VSX: 11 24 25.47 +77 42 15.3
I use VSX values:

hrs = 11 + 24/60 + 25.47/3600 = 11,407075
RA_ASTAP=hrs*864000/24 = 410654.7

ASTAP variable_stars_13.csv
410652,279735,V0451_Dra 12.9R1-13.4R1_Period_0.0558

Why this difference ?

CS
Thomas

[han.k]

The star proper motion is not included in your position. It is the position at epoch 1 jan 2000 in coordinate system J2000.

During tests, there where one or two stars not at the correct position due to the high proper motion. so I have calculated all positions for epoch 2027. This is remarked in the header of database. So it should be fine for the next 6 or 8 years.

Attached a small part of my database. V0451 DRA is at the first position. The proper motion is at column V, W

You can set in the output options of Simbad the epoch at e.g. 2027 and keep coordinate system equinox at J2000, See attached screenshot

Cheers, Han

[han.k]

I'm working on an option for specifying an ensemble manually. Attached just a concept. A lot of work to do. And testing...

[Thomas Rudolph]

Wow, that would be a great help, thank you for your effort.

P.S. Sorry for additional work ... but since the AAVSO format does not contain the measured values of all stars, would it please be possible to export the values, just any csv file, no special format ?

[Aengus O'Fearghail]

Han

I'm in the Flare Group that is studying AD Leo.
So thank you for the work. on the selection of ensembles.

Aengus O'Fearghail