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Baffled by DSLR tutorial

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Baffled by DSLR tutorial

I am going though the Calibration:Beginner dslr tutoral for AIP4Win and things went very well until steps 4 and 5. Very little makes sense at this point.


From Step 4:

'Type the instrument magnitudes for your check stars in the yellow cells of the “Check I Mag” column and for your variable star in the yellow “I Mag” column cells.'

Check Star(s)? There are multiple check stars? I understood only one star was labeled as such, the others are comps. What are /where do the values come from that are exampled? 

Based on the supplied tutorial image's, just how many instruments mags. should there be for the variable?


From Step 5:

Where do these entries in the  'Images' columns come from? I don't see any of these in the sample data.

Help clarifying this would be appreciated.

The yellow 'Check I Mag' and 'I Mag' columns appear each to be samples of single objects. If so which objects and how were multiple samples derived?

Dan, TDB

One row for one exposure/stack

Hi Dan,

In step 4/5 there are multiple rows. Each row corresponds to a single exposure (or stack of exposures) you want to reduce. So if you reduce each exposure one by one, you will have one row for every exposure. Likewise, if you stacked all of the images into one exposure, you will have one row.

Each one of these rows should receive the (singular) instrumental magnitude from the check star and the (singular) instrumental magnitude from the comparision star from the image (or stack of images) that were used to create the exposure you are reducing.

I hope this helps,

Brian Kloppenborg

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