Jump to content

Need a good target to get to grips with - Any suggestions?


swag72

Recommended Posts

I don't mean to, but I keep imaging hard galaxies!! I need to do something that I can get to grips with regarding my processing. I can see all around me, but my sky is best to the north and East.

I am imaging using my SW 120ED at 900mm and f7.5. I have a mono Atik 314L and Baader filters.

So, what would you recommend? I'm not struggling too much with the data capture - I need to get some understanding regarding processing.

Link to comment
Share on other sites

It's a bit of a lean time for the shorter focal lengths till the MW rises again with its nebulae. How about some of the Elliptical groups in Virgo? Markarian's chain, or some of it. The Eyes are nice.

I find galaxies very hard to process. The faint outer stuff is very faint. The colour tends to start off as a rather even, pasty green all over. In close proximity in the image are inter-arm regions that need smoothing and the arms themselves that need sharpening. The cores tend to over expose. Well, apart from that they're a cynch!

In planning a processing campaign I'd break it down into its component problems.

L channel, at least 2 streches, core and arms (possibly three, outer glow, core and arms) and use layers to get the best of each stretch.

Then do a smoothed layer and a sharpened one and take what you want from each using Layers.

Colour; to break open the even green I try opposed contrast boosting curves in red and blue. After pinning the background in all colours I give the red a tiny dip near the bottom and a tiny boost near the top, on the ground that the bright cores with their Population 2 stars are redder. In the blue I give the curve a tiny lift in the mid ranges (spiral arm terrirtory, hot young stars) and a tiny dip for the bright, old-star core. These adjustments are tiny but just get the colour balance to tip in the right direction, usually.

Then you can try a special curve for the surrounding starfield using only RGB, not LRGB. Stretch to get the background up to the main image but roll off the curve quite low to keep the stars small. Another Layer and you're done. (I couldn't do this on our recent M81/82 because we wanted to keep the Integrated Flux Neula in the starfield.)

In general, when processing, try to break down the image in terms of the needs of each part of it.

Olly

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.