Quote:
Originally Posted by multiweb
Pretty cool! Massive field, deep with nice colors.  |
You are very correct Marc as regards the colours. With a 75 sec exposure even the bright stars in this field are not saturated in the raw fit data.
Below is a line profile of the star Eta Car from a single exposure.
When I correct for flats and darks with PixInsight I convert to 32 bit floating point data.
All further steps are done at 32 bit. Sixty four bit is also an option.
The real advantage of 32 bit data is that all the dim stuff is in the bottom few binary digits and when stretched there is plenty of head room for the bright stars so they do not saturate.
I also use a module in PI called HDRMultiscaleTransform which enhances the hidden (to 16 bit) detail in the very bright areas.
This is why the very dim dust and nebular detail is visible without blowing out the bright bits.
I hope that makes some sort of sense. Bert