Login  Register

Re: Extinction Coefficient

Posted by karenacollins on May 24, 2019; 6:58am
URL: http://astroimagej.170.s1.nabble.com/Extinction-Coefficient-tp1128p1159.html

HI Marina,

That is correct.

Karen

On 5/23/2019 6:13 AM, Chatzisotiriou Marina [via AstroImageJ] wrote:
Hello Karen,

Thank you for your answer! I would like to ask another one. I want to measure the counts of a star within an aperture but without the background. In order to do that I set the object aperture and around it an inner and outer background aperture and I use the value given in Source-Sky. Is this correct?

Thank you,
Marina



On "karenacollins [via AstroImageJ]" <[hidden email]>, May 16, 2019 5:15 AM wrote:
The total ADU counts in aperture NN are given in the data column Source-Sky_TNN. I think you would need to know what absolute flux an ADU corresponds to for your telescope and camera. Alternatively, I think you would need to relate the Source-Sky_TNN counts to counts from another star for which you know the AB magnitude. I don't have experience using the AB magnitude system, so I can't give much guidance.

Maybe someone else on the forum is able to help?

Karen




If you reply to this email, your message will be added to the discussion below:
http://astroimagej.1065399.n5.nabble.com/Extinction-Coefficient-tp1128p1157.html
To unsubscribe from Extinction Coefficient, click here.
NAML



If you reply to this email, your message will be added to the discussion below:
http://astroimagej.1065399.n5.nabble.com/Extinction-Coefficient-tp1128p1158.html
To start a new topic under AstroImageJ, email [hidden email]
To unsubscribe from AstroImageJ, click here.
NAML