Four Panel Carina Mosaic

[avandonk]

This is a mosaic of four panels taken in one night. It takes 1.6 hr to obtain each panel.

Data. 20x75sec for each of RGB respectively for each panel. The data was binned X2.

Binning X2 increases the speed of the system by a factor of four with an obvious loss of resolution. PixInsight's drizzle integration gets most of this back.

Large image here 14MB. FoV 6.5 X 5.8 degrees.

https://www.flickr.com/photos/34386396@N08/46561495295/in/photostream/

Hope to do more like this of areas not usually imaged around familiar objects to put them in context.

Bert

[multiweb]

Pretty cool! Massive field, deep with nice colors. :thumbsup:

[avandonk]

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