Astrophotography - 6 months in...

[LiamMcD (Liam)]

Hi All

I hope that 6 months still counts as a beginner

But the wife is tiring of my asking her to comment, so I need some fellow aspiring APs to give me some critical feedback.

Attached are my best 5 APs so far. Let me know what you think.

By far the most difficult thing to learn, is post-exposure processing, and I feel like I've only seen the tip of the iceberg.

All photos;
Astronomik CLS filter
Dark subs, Nebulosity, PS Elements
Canon 1000d with Nebulosity
Nextstar 8se OTA on CGEM (f6.3)
Guided ST80 with PHD

Specifics:
Trifid Nebula (M20)
5 subs @ 300s each
ISO 800

Sombrero Galaxy (M104)
10 subs @ 150s each
ISO 1600

Omega Centauri (NGC 5139)
5 subs @ 120s each
ISO 800

Southern Pinwheel Galaxy (M83)
40 subs @ 120s each
ISO 800

Eagle Nebula (M16)
30 subs @ 60s each
ISO 800

Thanks in advance
Liam

Clear skies!

[cybereye (Mario)]

Liam,

Very nice photos indeed! It looks as though you've lost a bit of detail in the Triffid Nebula but the others look really good.

Keep up the good work,

Cheers,
Mario

PS I knew I'd taken a good image of the Orion Nebula when my wife asked "Who took that?" You've got to love them!!!!

[Geoff45 (Geoff)]

I had a quick look at the trifid and m83 in Photoshop. The black points of both are severely clipped, so you've removed a lot of faint detail in processing. Even so, a stretch in curves brings out a lot more detail.
So what I'm saying is that the data looks good, but the processing hasn't used it to best advantage.
Geoff

[LiamMcD (Liam)]

Hi Mario/Geoff

Thanks for the replies and encouragement.

@Mario - I used to use in-camera long exposure noise reduction, but after reading more cons than pros for it, I now take separate darks (I use 10-20% of the number of light frames).

@Geoff - I'm busy travelling, but when I'm back, I'll give them another bash processing and see if I can get improvements like you got. I'll let you know. Thanks for the tip!

A general comment, I gather that Flats are pretty important too, and plan on getting this right in the next month or so.

Thanks again

Clears Skies
Liam

[rcheshire (Rowland)]

Liam. Is the filter the clip-in type, the new CCD-CLS that Astronomik are advertising, and is your camera modded? Lots of great colour, by the way.

[RobF (Rob)]

Nice going - you've got some really nice pics together there. Posting regularly on IIS is certainly a great way to gets lots of helpful crique and encouragement.

I agree on black point comments - there will be extra faint detail in there if your background noise allows it to come out. Processing is a steep and long learning curve in its own right - you're not learning if you don't look back at your pics every few months and think "hmmm - I just MIGHT be able to make that look better now....!)

[Hagar (Doug)]

Nice collection of images Liam. A couple of tips which might help you along the way.

1. Pay particular attention to the black point of the histogram when processing up the images. Clipping the black point costs some data in the original capture which is lost for ever.

2. Use a good set of dark frames to help control noise. I fear you have clipped the black in an attempt to remove background noise.

3. Extend your exposure duration and amount. Nothing else you do will improve an image more than overall exposure.

Nice start.

[LiamMcD (Liam)]

Hi Rowland/Rob/Doug

Thanks all for the comments and encouraging words. I must say that I find AP to be very rewarding as related to the hard work that goes into it, and appreciate the effort behind other's images I see posted. I take my hat off to you pro's!

@Rowland - yes, I'm using the clip-in CLS filter from Astronomik for the Canon. Very useful, but quite pricey imho. My Canon is still un-modded, but I'm getting more tempted to try and do the mod...

@Rob - Processing is by far the most difficult thing I've had to try and master in a while. I've been trying to improve my results as suggested by you and the others for a couple of weeks now, it's like being in a hamster wheel! Luckily I've been bitten by the 'go back and do it better than last time' bug - so I suppose it's more of a learning loop-the-loop than a curve

@Doug - New moon this coming weekend, and I'll put your suggestions into practice, and let you know. PS - You are correct about me clipping to eliminate background noise... *guilty look*.

Clear skies to you all
Liam