Scorpius Globular - M4

Here is an M4 at somewhat low f/ratio and short subs exposure. I am amazed at how red this turned out but I hear that there is dust between us and M4 that creates the reddish appearance. This is a mid size image. A full size image and processing details are at:

http://jthommes.com/Astro/M4.htm

Exposure was in 60 sec Lum subs and 45 sec RGB subs (2x2)

Attached Image:

Jim,

Another excellent glob. I like the color of that one.

Keith

Nice one.

Greg.

That's a fine job of processing, Jim. Even the large size looks good. It's got great color and it's not overly sharpened. That makes for a natural processing style.
I have seen some images of M4 that show some blue stars, such as Jim Misti's:
http://www.mistisoftware.com/astronomy/Clusters_m4.htm
You might be able to increase your blue saturation a touch.
Have you tried shooting a glob with unbinned RGB? I find the color easier to process that way, and it doesn't seem to affect the depth of the image.
I liked the M4 links to the mouse-over and other images on your site. The wide field views give us a good sense of M4's neighborhood.
My regards,

dan

Wow, another beauty!

Tom

Thanks for the comments everyone..

dan kowall said:

....

I have seen some images of M4 that show some blue stars, such as Jim Misti's:
http://www.mistisoftware.com/astronomy/Clusters_m4.htm
You might be able to increase your blue saturation a touch.
Have you tried shooting a glob with unbinned RGB? I find the color easier to process that way, and it doesn't seem to affect the depth of the image.
I liked the M4 links to the mouse-over and other images on your site. The wide field views give us a good sense of M4's neighborhood.
My regards,

dan

Dan,
I saw Jim Misti's image. I believe he has deeper saturation across the whole pallett. And certainly the blue comes out more noticeably. I could go back and touch the blue, but I have been trying to work on the color calibration and extinction effects into images - I think there is a lot of ways color error can come in though. My first impulse would be to see what tweaking saturation does before adjusting balance. I do usually try to balance a "black" point while keeping midrange and white point unchanged (Sampler tools in PS) - I try not to stray too much beyond that.

I have tried unbinned color before (on a cluster as I recall). I will sheepishly admit it was unintentional (a senior moment while exposing). I believe it was M48:

http://jthommes.com/Astro/M48.htm

Other than not needing to resize, I don't think I noticed a difference in processing (of course, I wasn't looking for one at the time). Do you think there is a potential difference in image quality? Seems like a increased investment in exposure time.

Very nice image Jim!

Dan,
OK, now I see the point in unbinned RGB's - you then don't use (or need) a luminance. Your detail remains at the best resolution your camera has and the hue shifts you can get with a luminance processing are avoided. The trade off as mentioned is the longer exposure time, but now I see the benefits, thanks.

Matt,
Thanks for the comment on the image. Yes, I do tend to clip the black level a bit with clusters - particularly if I don't expect anything faint or fuzzy in the frame.

All,
Looks like i am on Holiday for a week or so. I will check back in when I get back.

Nice image Jim. The reddish tint would make sense due to the object being filtered through the gas clouds in the band of the milky way. I have noticed a reddish hue in most of my RGB images that were taken near the center of the galactic nucleus, B72, M8, etc.

Vince

Jim I really love this M4 shot of yours !