Astrofest collection

peter_4059 (Peter) · #1 19-08-2011, 08:32 PM

I finally got around to processing the images I took at Astrofest. Happy with how some turned out but had a lot of issues with tracking for some reason this year.

NGC6334 (24x5mins)
NGC6357 (16x5mins)
Corona Australis (23x5mins)
M16 (17x5mins)
Rho Orphiuchus (27x5mins)
IC2948 (40x5mins)
M20 (37x5mins)
IC4628 (27x5mins)

All processed in PS but intend to go back over the data with Pixinsight when time allows.

Comments/advice welcome.

Thanks for looking.

peter_4059 (Peter) · #2 19-08-2011, 08:36 PM

last few

M17 (16x5mins)
NGC5128 (19x5mins)
NGC3324 (20x5mins)
Eta Carina (11x5mins)

jjjnettie (Jeanette) · #3 19-08-2011, 08:38 PM

An amazing collection Bester.
I remember the Running Chicken night. The rest was a bit of a blur.
And that may indeed be the explanation for your tracking issues.

Contratulations on a damn fine set of images.

alan meehan (Alan) · #4 19-08-2011, 08:44 PM

Fine collection of images Peter you done better than i did,good luck on re process with pixinsight.
AL

troypiggo (Troy) · #5 19-08-2011, 09:20 PM

Mate, fantastic collection! Well worth the wait!

ozstronomer (Geoff) · #6 19-08-2011, 09:30 PM

Great Shots Pete, that's certainly an impressive collection, they have come up really well.

Be interested to see the difference if you redo any in Pixinsight.

jase (Jason) · #7 19-08-2011, 09:33 PM

Awesome portfolio Peter! You're on fire! Really like NGC6357 and the composition for NGC3324 is excellent. Have not seen it framed that way before. As you suggest a few could do with a touch up, but wow there is certainly some productive imaging going on. Well done.

Ross G · #8 19-08-2011, 10:04 PM

Great photos Peter.

I really llike your Centauras A.

Thanks.

Ross.

h0ughy (David) · #9 19-08-2011, 11:49 PM

some really nice shots there Peter. did you ice up on a couple or were your flats not quite right? The trifffid looks a little green. I like the Corona Australis shot.

glenc (Glen) · #10 20-08-2011, 02:38 AM

That is an amazing collection of impressive nebulae images Peter.
The one of rho is actually IC 4603. Rho (IC 4604) is 1 deg north of that.

Dennis · #11 20-08-2011, 07:02 AM

Wow Peter – that is a superb set of images. Surely, you must win the “imaging factory of the year” award at astrofest for this prodigious output!

Thanks for the views.

Dennis

peter_4059 (Peter) · #12 20-08-2011, 08:22 AM

Quote:

Originally Posted by jjjnettie

An amazing collection Bester.
I remember the Running Chicken night. The rest was a bit of a blur.
And that may indeed be the explanation for your tracking issues.

Contratulations on a damn fine set of images.

Thanks JJJ. You might be on to something there.

Quote:

Originally Posted by alan meehan

Fine collection of images Peter you done better than i did,good luck on re process with pixinsight.
AL

Thanks Al. Despite the nights being cut short by cloud and/or fog I did manage 1-2 images each night. Not as productive as previous years but plenty of data to process.

Quote:

Originally Posted by troypiggo

Mate, fantastic collection! Well worth the wait!

Cheers Troy. This is the first time I haven't rushed the processing and actually came back to the image a couple of days later. In most cases I wasn't happy with how it looked and re-did several of the steps. I also went to the trouble of flattening, resizing and changing to 8 bit before saving for web and paid more attention to the black point in the jpeg and I think this paid off.

Quote:

Originally Posted by ozstronomer

Great Shots Pete, that's certainly an impressive collection, they have come up really well.

Be interested to see the difference if you redo any in Pixinsight.

Thanks Geoff. It is nice to have a few keepers to show for 10 days of imaging!

Quote:

Originally Posted by jase

Awesome portfolio Peter! You're on fire! Really like NGC6357 and the composition for NGC3324 is excellent. Have not seen it framed that way before. As you suggest a few could do with a touch up, but wow there is certainly some productive imaging going on. Well done.

Thanks Jase. I'm really pleased with how the NGC6334 and NGC6357 images worked out as I've had several attempts at these objects but have never been happy in the past.

Quote:

Originally Posted by Ross G

Great photos Peter.

I really llike your Centauras A.

Thanks.

Ross.

Thanks Ross. It was quite difficult to process compared to previous attempts - I suspect there was some high cloud around while I was imaging it.

Quote:

Originally Posted by h0ughy

some really nice shots there Peter. did you ice up on a couple or were your flats not quite right? The trifffid looks a little green. I like the Corona Australis shot.

Cheers Dave - I don't think the camera iced up this year - haven't had that problem since I filled it with argon. I normally apply threshold as a first step to find the black point and this usually reveals flat issues however I don't recall seeing this in these images. I haven't viewed all the flats in detail but will have a look. Did you think the flats were not right in all images or particular ones? Had a lot of trouble getting the triffid to look right - especially the blues but was very happy with the detail in the dust, especially at the bottom left hand side.

Quote:

Originally Posted by glenc

That is an amazing collection of impressive nebulae images Peter.
The one of rho is actually IC 4603. Rho (IC 4604) is 1 deg north of that.

Thanks Glen

Quote:

Originally Posted by Dennis

Wow Peter – that is a superb set of images. Surely, you must win the “imaging factory of the year” award at astrofest for this prodigious output!

Thanks for the views.

Dennis

Thanks Dennis - we missed you up there!

CoolhandJo (Paul) · #13 20-08-2011, 08:26 AM

Wow. So many great shots. Production factory!

allan gould · #14 20-08-2011, 03:28 PM

Most excellent images Peter. Well composed and processed as usual.

strongmanmike (Michael) · #15 20-08-2011, 03:54 PM

12 images from one star party - nice work!

Like looking at a set of holiday pics

One day I'll get to an astrofest

Mike

multiweb (Marc) · #16 20-08-2011, 04:35 PM

Great set of pictures Peter. Excellent focus.

Are you flat fielding?

RobF (Rob) · #17 20-08-2011, 04:42 PM

Quote:

Originally Posted by glenc

That is an amazing collection of impressive nebulae images Peter.
The one of rho is actually IC 4603. Rho (IC 4604) is 1 deg north of that.

Whatever it is, this one is my fav

Congrats on a fantastic portolio Peter

peter_4059 (Peter) · #18 20-08-2011, 05:06 PM

Quote:

Originally Posted by CoolhandJo

Wow. So many great shots. Production factory!

Cheers Paul. It is nice to be able to leave everything set up rather than have to cart it in and out of the house each night.

Quote:

Originally Posted by allan gould

Most excellent images Peter. Well composed and processed as usual.

Thanks Allan. There is always more to learn about processing!

Quote:

Originally Posted by strongmanmike

12 images from one star party - nice work!

Like looking at a set of holiday pics

One day I'll get to an astrofest

Mike

Thanks Mike - it would be good to see you up here! Maybe next year?

Quote:

Originally Posted by multiweb

Great set of pictures Peter. Excellent focus.

Are you flat fielding?

Thanks Marc. I am doing flats, bias, darks and dark flats in DSS. I've had a look at a few of the flats (I take a set each night as I remove the camera) and they all look similar. Histogram between 30% and 50% in PS. I've attached a typical master flat created by DSS after combining 20 raw flats.

Quote:

Originally Posted by RobF

Whatever it is, this one is my fav

Congrats on a fantastic portolio Peter

Thanks Rob. Wish I had a wider FOV for this one though.

multiweb (Marc) · #19 20-08-2011, 05:29 PM

Quote:

Originally Posted by peter_4059

I am doing flats, bias, darks and dark flats in DSS. I've had a look at a few of the flats (I take a set each night as I remove the camera) and they all look similar. Histogram between 30% and 50% in PS. I've attached a typical master flat created by DSS after combining 20 raw flats

I'm asking because you have a gradient on all your shots which is consistent with over correction with flat fielding. The center of the field goes darker and the corners lighter. This is usually caused by a flat/bias wrong combination or the flat ADU level being a tad too low. I've battled with this issue for months. Drove me nuts. It is more obvious on the very faint stuff like Rho.

peter_4059 (Peter) · #20 20-08-2011, 08:14 PM

Quote:

Originally Posted by multiweb

I'm asking because you have a gradient on all your shots which is consistent with over correction with flat fielding. The center of the field goes darker and the corners lighter. This is usually caused by a flat/bias wrong combination or the flat ADU level being a tad too low. I've battled with this issue for months. Drove me nuts. It is more obvious on the very faint stuff like Rho.

Thanks for the heads up Marc - how do you tell if it is a problem with the flat or the bias? I'm taking flats to get the histogram between 30-50% and the bias at 0.001 s.