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gregbradley
10-01-2011, 01:22 PM
I had a dream run of weather at my dark site over the Christmas break. I had 10 out of 12 nights clear and 1 night clear for several hours.

It seems to me that the western side of the Great Dividing Range (leeward side) is the drier side and the usual weather pattern is that even if its cloudy during the day it very often clears after dusk when the air cools a bit and the clouds are reabsorbed so you often get completely cloudless nights. So if you are looking to find a nice location for dark imaging in NSW then I suggest the western side of the mountains. I have seen it time and time again. I left Sydney and it was completely overcast only to find completely cloudless skies all night there.

Seeing was variable with 3 nights of excellent seeing and several where it was OK to poor.

I managed to image the Pleiades on the night that had cloud come in at about 2:00 am giving me about 4 hours of available imaging time (dark is about 10pm now) .

AstroPhysics 140 scope with specialised reducer/corrector giving F5.6. This is no ordinary reducer as it gives .75X reduction but it also corrects the field so its pinpoint stars corner to corner on a 16803 chip.

A remarkable optical achievement. Such a great scope.

I wanted to bring out the background dust and nebulosity and managed to do so to some degree. As usual more hours would add but its at a good point here.

LRGB 30 40 20 40 minutes FLI Proline 16803, Astrodon Gen 11 filters and Tak NJP mount at my dark site observatory at Bigga NSW where the wild goats and goannas roam and the occassional Kangaroo says hello.

http://upload.pbase.com/gregbradley/image/131717600/original

Here is a darker version of the same area with less background showing but better contrast:

http://www.pbase.com/gregbradley/image/131722349

Here's a photo of the setup:

http://www.pbase.com/gregbradley/image/131718019/large


Greg.

iceman
10-01-2011, 01:26 PM
Wow, that's beautiful. Incredible work Greg!

TrevorW
10-01-2011, 01:32 PM
very nice Greg, plenty of detail, but bright may need to tone it back a bit IMO personal taste

gregbradley
10-01-2011, 01:37 PM
Thanks Mike. I was happy to be able to bring out the background dust given the exposure time. The dark skies certainly help.



Thanks Trev. Yes it is pretty bright. But hey, I already pulled it back!! hehe. If I pull it back more I lose the background dust as I have already looked at that. So its a compromise really.

Greg.

h0ughy
10-01-2011, 02:40 PM
WOW, yes it is bright but it is beautiful. you did well with the weather.

in a word - Awesome

strongmanmike
10-01-2011, 03:14 PM
Really lovely Image for a quicky Greg.

The brightness looks ok to me...but it would be interesting to see a dimmed version with more highlights, just for interest to compare. The short exposure time looks to have necessitated a bit of smoothing especially in the outer regions..?

...Aaarggllll... the that setup looks veeery sexy...:evil2::question:..I'm off to be alone..?...with mine :rundog:

Mike

DavidTrap
10-01-2011, 03:32 PM
Very impressive Greg, but on my calibrated monitor, I also feel that it is too bright. Would something like "Shadow-Highlights" be able to bring it back a bit - that is currently my favourite photoshop tool, I've been using it quite a bit processing my holiday pics, unfortunately not astronomical shots (apart from the moon visible in the sunrise & sunset shots).

I have my name down on the waiting list for the AP140... Let's see what the world holds in 10+yrs time. My hunch is that it will be too heavy for my mount and imaging gear (limit 20kg), so I might have to settle for the 130 (on the list for that too!), or upgrade the mount...

I got a Christmas card from AP in the post today. I presume you get one in the year after you buy something from them. Wonder if you they send you one while you're on the waiting list???

DT

gregbradley
10-01-2011, 04:30 PM
I couldn't believe my luck with the weather. After so many cloudy nights here in Sydney and driving into clear skies it seemed surreal.




A darker version here:

http://www.pbase.com/gregbradley/image/131722349

It doesn't show the background dust so much but gives better contrast. Always a compromise one way or the other unless you get megadata.



Thanks David. I posted a darker version reined in a bit more and it gives more contrast.

I got this scope 2nd hand (it was 3 months old) so no Christmas card for me! I have my name down for a Riccardi Honders but no notification yet.

The scope is quite chunky and heavier than you'd expect for the size.
With the camera, guide scope and filter wheel plus rings and finder scope it would be well over 20kg.

Did you know the tube is made from a solid piece of aluminium and hollowed out? The tube has baffles machined into it. Amazing eh?

Greg.

DavidTrap
10-01-2011, 05:19 PM
Thanks Greg for the info. I thought it would be well over 20kg, but the 130 would probably be doable.

I much prefer your darker version. I had a quick fiddle with your first image using Shadow-Highlights and achieved something similar. I didn't think you lost too much background dust.

Cheers
DT

strongmanmike
10-01-2011, 05:20 PM
:eyepop:.....:sadeyes:.... :bashcomp: .....:mad2:.....:drink: :drink::drink:.......:violin:


:P

Alchemy
10-01-2011, 05:38 PM
Stunning image Greg, you've done really well, as for too bright :shrug: works for me, they are very bright stars after all. Plenty of extended nebulosity too.

As for the clear skies.... Might as well be on mars given I don't consider my gear portable. Currently raining here... All week too.

spearo
10-01-2011, 05:43 PM
Greg,
love the dark version
frank

multiweb
10-01-2011, 06:18 PM
A truly magic picture Greg! I'm in awe. :prey2: Love it! :thumbsup::thumbsup::thumbsup:

Hagar
10-01-2011, 06:25 PM
Lovely image Greg. A quicky, my God you have squeesed every bit of gas and dust in the area into this image. What are the single dif spikes on your stars? ?Shutter maybe.?
Very impressive image.

gregbradley
10-01-2011, 06:36 PM
Thanks Frank. Yes I like it too now.



Wow, thanks Humi.



Thanks, I try to get the most out of it. The diff spikes? I am not sure where they come from. The camera for sure but what I don't know.
One person said it was the screws in the filter wheel and if you blacken them they go. I blackened mine with a permanent marker and it made no difference. I don't think the Microline does this and I saw an image with a Microline 16803 and no spikes so something to do with the Proline.
It doesn't bother me particularly but it would be good to isolate the cause.

Greg.

Paul Haese
10-01-2011, 06:37 PM
Superb image Greg and I reckon probably you best yet. Detail is great colour and contrast all lovely in my opinion.

gregbradley
10-01-2011, 06:40 PM
Why thanks Paul for the nice words.

Greg.

renormalised
10-01-2011, 06:52 PM
Both great piccies, Greg. Ace setup too with the AP :):)

pgc hunter
10-01-2011, 07:01 PM
wow look at all that nebulosity! Definately the best image of the Pleiades I've seen.

gregbradley
10-01-2011, 07:39 PM
Thanks for that. I hope you are OK up there with the flood problems in Qld.



Gee thank you, high praise.

Greg.

Exfso
10-01-2011, 07:54 PM
Wow, that is one sweet image.:thumbsup:

Peter Ward
10-01-2011, 08:18 PM
Your images have really gone into the A league of late.

Nice one :thumbsup::thumbsup:

gregbradley
10-01-2011, 08:46 PM
Cheers.



Thanks very much Peter.

Leonardo70
10-01-2011, 10:57 PM
Great shot Greg...

Amazing colors.

Leo

RobF
10-01-2011, 11:11 PM
Wonderful image.
Man what I've give to have that many clear nights in a row at a night tranquil dark sky site. Congrats Greg.

richardo
11-01-2011, 01:54 AM
Hi Greg,
lovely job of this!
Nice tight focus and very well processed!
My pick, and it was a hard one, is actually the lighter version.... the faint wisps look excellent... my thinking, is that with the high mag of those blue stars, the light would definitely be hitting every bit of dust surrounding the area... so that's my choice and I'm sticking to it!

I can never get a shot at this and it would be the ultimate for me having sooo much reflection in it.... but it's too low to give it a reasonable go. So I do enjoy looking at others images of this lovely object and this is a gem!

Great stuff.

All the best
Rich

strongmanmike
11-01-2011, 09:23 AM
Man...you must have an astronomical angel looking over you :eyepop:...how many images will be forced to look at with envious eyes then? :rolleyes: :lol:

This latest version of M45 is pretty darn good Greggles :thumbsup:

Mike

suma126
11-01-2011, 03:12 PM
excellent image :thumbsup: :thumbsup: :thumbsup:

marco
11-01-2011, 04:33 PM
Hi Greg, nice image of the seven sisters, maybe a bit too "strong" to me. I definitely prefer the darker version, perhaps with a tad less de-noise.
What is surprising me is the amount of details and the beautiful color balance you got, I supposed Pleiades to be too loo on horizon from down-under to be easily imaged. This prompt me to give them a try from Coonabarabran, when this %#=% weather will give more than few hours of clear (it has been raining most of time there for the last two months..)

Clear Skies
Marco

Doomsayer
11-01-2011, 05:47 PM
A very eye carching rendition. Very envious of your amazing clear sky run too.
guy

gregbradley
11-01-2011, 07:40 PM
Thanks Leo. It's a rich area for sure.



Thanks Rob. Yes it was a wonderful change from the usual cloud in the Sydney area for so long now.



Thanks Rich. I like the bright version as well as it shows up the dust areas better but it does lose some contrast as a result.



Thanks Mike. Yes there are a few in the works.;)





It is quite a low target for sure. I understand it may be too strong for some. I guess these are the processing choices I made that reflect my view on it which won't of course be shared by all. That's art for you.



Yes I felt like I won the lottery.

Greg.

alexch
11-01-2011, 08:59 PM
I am a bit late to chime in but what an excellent image! The light version shows the Pleiades like I haven't seen before.

Cheers,
Alex

marc4darkskies
11-01-2011, 10:00 PM
Whoa!!! An in your face spectacular image Greg!! :thumbsup: Well done!!

Cheers, Marcus

Octane
11-01-2011, 10:28 PM
Agreed with everyone else, mate, this is super!

How about you try and layer mask the two, so you get the best of both worlds? Might be a good way about getting the rendition you had in your minds eye when capturing.

10 out 12 clear nights. What I wouldn't give...

Well done, mate. : )

H

John Hothersall
11-01-2011, 11:22 PM
I though this image will only be good if its deep and WOW that is so deep with detail everywhere you look with brown gas too.

John.

gregbradley
12-01-2011, 06:57 PM
Thanks Alex. It does show a lot of the background dust which I wanted to capture.



Thanks Marcus.



That's not a bad idea. I'll try that. Cheers Humi.



Thanks John. I was very happy with the result.

Greg.

alan meehan
12-01-2011, 09:28 PM
Greg iam speechless what a beautiful image the best i have seen .
AL

gregbradley
13-01-2011, 06:15 AM
Thanks very much Alan, I appreciate your kind words.

Greg.