M106

[Astrodoc]

My image of m106 appears on the back cover of the Journal of the Royal Astronomical Society of Canada June 2014 issue.  Image and processing details at http://astrodoc.ca/m106-galaxy/

Working on a 40 hr exposure of M101 - 27 hr20m so far...

Clear skies,
Ron

[dayers]

Hi Ron,

I have done some imaging of M106 using a hired scope, and I was wondering what additional hours of exposure would do. Yours is a fine image, and congratulations on being selected for a cover illustration.

A question about selecting black level. I have noticed (I think) that if I set the sky at about 0.2000 when viewing stretched FITS image, when I convert to JPEG for the web it seems to come out almost black. In your online image, for example, I had to dig deep before I could see that your background was really a little uneven, as it should be IMO, not clipped black as it first appeared to me. Is there a reason for this, or am I missing something?

Best,

Dave

[Astrodoc]

I'm not sure.  Are you using a fully colour-managed workflow?  I calibrate my monitor using a Spyder3 Pro device, and I do this regularly.  I save colour profile info with my images.  I aim for a background in the 0.02-0.05 range , and I take great care to clip VERY little if any data.  Also - I recommend doing the "conversion" using PixInsight's Save As command?  Other methods I have tried have had some issues related to bit depth and colour rendition etc. going from FITS to JPG. 

Hope this helps.

Clear skies,
Ron

[Ignacio]

I like everything about this image. Its intense and dramatic, particularly at the galaxy core, but it also feels natural.

Congratulations for making the back cover!

Ignacio

[dayers]

Thanks, Ron.

I try to keep my monitor color calibrated, but no doubt should pay more attention to that. I'm using Huey, which I suspect is not too rigorous.

Thanks also for the tip about using Save As for converting to JPG.

Dave