DSLR Photometry Tutorial / Starting Analysis

Starting Analysis

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Submitted by bkloppenborg on 04 February 2010

Before you start imaging and analyzing your own data, we suggest you use one of our tutorials and sample data sets to learn the steps for obtaining a raw instrument magnitude. We have created two sets of data that include a minimal number of images for this purpose. The Beginner data file was taken under ideal observing conditions and may be reduced by any Final Reduction Method. The Intermediate level data was taken at higher air mass and requires the Intermediate Level Final Reduction method to get good results. Both data sets may use either the AIP4WIN, IRIS, or MaximDL tutorial listed below to extract instrument magnitudes.


If this is your first time going through these tutorials, we suggest using the Beginner Data File. Once you become comfortable with this one, you might give the Intermediate Level Data file a try. Either way, please download a copy of the sample data and extract it (to a convenient directory) before you proceed through the tutorials. Also have the standard stars page open in the background so you can refer to it when needed.


Final Reduction Level


Size (MB)


12 RAW Cannon (CR2) files taken as 5-second exposures at F/4.0, ISO 800 on 26 Jan 2010.



Nine RAW Cannon (CR2) files taken as 5-second exposures at F/4.0 ISO 1600. These data were taken at air masses of ~2 and require the intermediate-level final reduction spreadsheet.



The tutorials below contain step-by-step procedures for processing digital images to yield instrument magnitudes, which are then used in the next step, Final Analysis. All of the tutorials assume you know how to load your camera’s RAW format images into your computer.


Reduction Software





After you have finished the tutorial in one of the reduction packages proceed to the next step, Finish your Analysis . Here you will create calibrated visual or V-magnitudes for the variable star(s) in your image.

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