Drizzle integration & PCC

ktownsend

Well-known member
Can anyone suggest an answer to this please. I have recently started using drizzle integration and cannot get Photometric Colour Calibration to plate solve the images. I have tried all sorts of suggestions re pixel size, using no drizzle fits to obtaine header coordinates, force plate solving etc etc. Nothing works, which is weird.
The pixel size is halved automatically and the focal length is correct. The image is uncropped and the galaxy is centred, so I am at a loss to know what to do other than abandon using PCC.
Thanks in advance
 
Most folks find some cloud storage somewhere (DropBox; OneDrive; etc) and post a link. That way other forum readers can offer helpful advice!
 
That's certainly a very pejorative and restrictive view of the drizzle algorithm... :rolleyes:

Drizzle is one of the most elegant and powerful image integration methods available in astronomical imaging. However, as any image processing algorithm and technique, drizzle requires an appropriate methodology. We really need to take a look at the OP's data to say something helpful.
 
I love the drizzle algorithm (I remember being really excited when it was first described for Hubble image processing). However...
... with my equipment I rarely have undersampled images, and in the UK I rarely have imageing sessions long enough to capture the number of images needed for good drizzle (I know I could use more nights, but that could mean just one or two targets a year where I live!).
So, if you really have undersampled images, and if you have at least 50, well-dithered subs, then by all means try drizzle. For me that might be once or twice a year.
 
in another thread it was mentioned that using image solver first and then PCC did the trick. I occasionally have an issue with PCC as well (always drizzle my pics). now, I apply image solver first and then PCC. so far, it works.
cs Joachim
 
Had the same issue, the trick I used in PCC Image Parameters for a drizzle of scale 2, was to divide the pixel size by 2.
marcus
 
the trick I used in PCC Image Parameters for a drizzle of scale 2, was to divide the pixel size by 2.
When I run DrizzleIntegration the pixel size (in the FITS header) is automatically divided by two in the header of the integrated image.
 
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