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A few (obvious) practical recommendations

Map size
Make an image twice the size of the primary beam (e.g. $2\times55''$ at 90 GHz and $2\times22''$ at 230 GHz for PdBI antenna) to ensure that all the area of the primary beam (inner quarter of the dirty map) will be cleaned whatever the deconvolution algorithm is used. However, avoid making a too large dirty image because the CLEAN algorithms will then try to deconvolve region outside the primary beam area where the noise dominates.
Support
Start your first deconvolution without any support to avoid biasing your clean image. If the source is spatially bounded, you can define a support around the source and restart the deconvolution with this a priori information. Be careful to check that there is no low signal-to-noise extended structure that could contain a large fraction of the source flux outside your support... Avoid defining a support too close to the natural edges of your source. Indeed, deconvolving noisy regions around your source is advisable because it ensures that you do not biased your deconvolution.
Stopping criterion
Choose the right stopping criterion.
Convergence checks
Ensure that your deconvolution converge by checking that Else change the values of the stopping criterion, in particular the number of clean components (NITER).
Deconvolution methods
If you want a robust result in all cases, start with HOGBOM. If you prefer obtaining a quick result, use CLARK but you then first need to check that the dirty sidelobes are not too large on the dirty beam. If you obtain stripes in your clean image:
Outside help
Always consult an expert until you become one.


next up previous contents index
Next: Wide-field imaging and deconvolution Up: Comparison and practical advices Previous: Comparison of deconvolution algorithms   Contents   Index
Gildas manager 2018-09-25