C/2006 W3 (Christensen) - Photometry


[upwards]

The Photometry of my comet images is made with MaxIm DL Version 3.22. This program offers a quite good possibility to easily perform the photometry of a series of images.

First I select some reference stars with a magnitude around the comet's mag using TheSky level VI. Only USNO magnitudes are used. The Aperture Radius of the photometry area depends on the size of the inner coma of the comet. In the case of comet C/2006 W3 (Christensen) I select the maximum Aperture of 20. Also the Gap Width is selected to its maximum size of 10. The Annulus Thickness is set to 5, not too much. The stars should have no neighbors around.

Obj1 = comet, Ref1-Ref7 = Stars

2008-11-30 by Bernhard Haeusler, Maidbronn, Germany


The result of the photometry made by MaxIm DL is the following graph:

The "curves" are resulting from different wheather conditons during the series of images.

It shows the performed photometry data of all selected reference stars and of the comet. The program is automatically snaping the "moving" comet on all images, no manual work has to be done. Finally I save the data on a .CSV file and load them into an excel sheet.

T (JD)

Ref1

Ref2

Ref3

Ref4

Ref5

Ref7

Obj1

245.480.134.741

13.713

11.600

13.444

11.854

14.982

13.886

12.590

245.480.134.957

13.701

11.621

13.432

11.858

14.982

13.887

12.574

245.480.135.172

13.689

11.670

13.426

11.871

14.963

13.860

12.552

245.480.135.388

13.687

11.659

13.424

11.868

14.973

13.869

12.554

245.480.135.603

13.688

11.673

13.424

11.881

14.949

13.865

12.561

245.480.135.818

13.691

11.675

13.419

11.876

14.965

13.853

12.561

245.480.136.033

13.687

11.663

13.426

11.873

14.965

13.867

12.557

245.480.136.248

13.707

11.632

13.429

11.863

14.983

13.868

12.566

245.480.136.463

13.708

11.618

13.448

11.867

14.960

13.879

12.587

245.480.136.679

13.712

11.617

13.436

11.862

14.965

13.888

12.587

245.480.136.894

13.710

11.608

13.436

11.867

14.979

13.880

12.604

245.480.137.109

13.707

11.611

13.433

11.859

14.989

13.882

12.615

245.480.137.324

13.711

11.618

13.439

11.863

14.970

13.879

12.631

 

 

 

 

 

 

 

 

Average

 

 

 

 

 

 

12.580

In excel I compute the average values of the object and use the computed value of 12.58 mag for the comet.

[upwards]

 

Copyright of all sites and images of this web: Bernhard Haeusler, Rimpar, Germany   MPC code: B82 Maidbronn