PSF Signal Weight X PSF Scale SNR

Rafael Sampaio

Seems to me that using PSF Scale SNR would be a good fit for dim, low spatial frequencies targets, like a reflection nebula, as you would prefer to maximize signal to noise ratio. And PSF Signal Weight would be a good choice for high spatial frequencies targets, like galaxies and nebulas with fine-scale details, when you want resolution, so weighting the quality of the stars become important.

Does it make sense to you? May it be a good strategy?  

BlockHead

Yes, this is certainly one way to approach these weighting schemes. PSF Scale SNR is agnostic to background brightness or star quality (unless the star fuzz exceeds the photometric aperture).

I am probably more conservative than you in that I might reserve PSF Signal Weight to star dominated objects (like clusters). However...if you watch my weighting treatise you will see the PSF Signal Weight and PSF Scale SNR do follow one another closely if the data is varying too much. 

-the Blockhead