Skip to main content

DSLR Photometry

4 posts / 0 new
Last post
Mike_F
DSLR Photometry

I am just starting out with dslr photometry.  What is the best data analysis package to use for a dslr image that actually has some instructions on using it with a dslr image.  Not sure which package would be the best.  

 

Thanks,

 

Mike

SFS
You might get more responses if you reposted under "Photometry"

That said, I am not sure that any of the packages tell you how to use them for photometric purposes.  I used AIP4WIN and found it capable of doing everything I needed.  The AAVSO DSLR photometry course includes material on using the various commerical packages.  But beware that the AAVSO DSLR course material ignores the topic of determining transformation coefficients.  Because nobody ever told me that I needed to fix the transformation equations to fit my particular telescope and camera, I wound up submitting more than 1,000 useless observations. 

Do yourself a favor:  Buy a CCD or [sic] CMOS sensor and a filter wheel, and do it the right way.

HBB
HBB's picture
Transformation Equations

Not sure I understand your statement about having to fix transformation equations to your particular telescope and camera.  That is the purpose of transformation coefficients.  They are for that particular setup only. You can’t use them on any other setup. So regardless of if it is CCD or DSLR, transformation coeffiecients are determined for each set up.  Also, the DSLR manual does tell you how to determine transformation coefficents.

Bernhard
Bernhard's picture
Muniwin

Hi Mike,

Muniwin is rather easy to learn and can handle 300 obs frames in a single progress.

see download  http://c-munipack.sourceforge.net/

The reducing steps are:

1) Convert the raw files to fits file format, using TG filter (tri color green), which is close to Johnson V

2) Time correction to UTC

3) Apply masterdark and 4) masterflat

5) Do photometry.. Here you have to look how big the aperture must be.. Do not have other stars within the variables aperture

6) Match all 300 frames (search for a master frame, by whom yo have he most star matches)

7) Plot a lightcurve ..differential photometry, the "Ensemble Option" with more compare stars provides more accuracy in mmag.

8) Save data, with the aavso extended file format, you have to select the correct magnitudes of the comparison stars.

 

mhhh... The Filter TG tri color green, is the non standard bayer matrix color filter. Every Canon, Nikon, Sony will have slightly different results.. So professionall astronomers admit the Johnson corrected V-filter more..

But my TG is very close to V, if I am comparing it to other CCD V filters..

And in the EE CEP Alert Notice, the principal investigator, wanted to have especially TG, TB, TR for some calculations of a spectral response function, he is studying.

TOM (Times Of Minima) can be done also with TG.

wbea

ps: @Barbara, very nice talk at the webinar!!! Regards Bernhard

Log in to post comments
AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484