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loki78
05-05-2012, 02:37 AM
Last week on the Wednesday morning, i was up about 2am and noticed it was clear so i decided to go out and have a go at some data for my first milky way shot. Started at stanwell tops (sydney person) which was blowing a gale. doh forot to check that. so i just drove inland randomly down heathcote rd and ended up stopping in some new suburb as it was getting late and setting up in a vacant construction block. Crazy. I need to build up a list of semi local dark(ish) sites around Sydney that dont involve hours and hours of driving.

Anyway i managed some data. Ended up with 16x20sec lights. 15 darks, stacked in DSS (first time using it) and touched it up after a bit with CS6 beta ( first time using that too). Using a 600D with the 18-55mm kit lens at 18mm and about F4.5 i think it was.

Was a good learning curve and considering the randomness of the night and location i ended up in and first time using various methods, i was fairly pleased with how it turned out. A good starting point to learn from anyway. Like learning eventually that DSS doesn't work with 600D raws so i had to get the DSS beta. Good times. That one was doing my head in.

Critique away, tips to help me improve are greatly appreciated.

Also, if any Sydney siders care to share any semi dark spots they go to that aren't 3-4hours away to a real dark site, jump in by all means.

supernova1965
05-05-2012, 12:55 PM
Nice Job:thumbsup:

multiweb
05-05-2012, 02:02 PM
Yeah top shot from Sydney. No gradient at all. :thumbsup:

loki78
08-05-2012, 01:15 PM
Thanks guys, to be honest i'm not sure what you even mean by 'gradient' as i just experimented with settings in photoshop till i found what i thought was the best look while staying somewhat natural. The learning 'curve' is steep. Hah.

Octane
08-05-2012, 04:05 PM
Wow, Jon, well done!

By gradient, we refer to uneven backgrounds.

These are typically found in light-polluted shooting environments or when the Moon is out.

What happens is that you end up with a light background tending to dark. Hence, a gradient.

You should head up to the pony club on new Moon weekends if you can get away from work. You'll really enjoy it and get to take some nice pictures.

All my early work was done there (actually at the paintball place at Kulnura before we migrated to the pony club at Mangrove Mountain). :)

Nicely done on your first attempt -- much better than my own attempts.

H

Forgey
08-05-2012, 06:58 PM
Very nice Jon !

cjpops
21-05-2012, 09:17 PM
Hi Jon,

Just saw this thread - i am also trying to achieve a similar result with my 600D - your milky way looks awesome!

Can i ask what ISO rating you had your camera set to?

cjamo9
21-05-2012, 10:46 PM
yes please, was it processed after dss and how

loki78
22-05-2012, 01:17 AM
Hey guys thanks for your comments. They were shot at ISO 3200 in and as for post processing, I couldn't really tell you. Was my first time using photoshop so i was just playing around with settings till I found a balance I was happy with.

I've attached one of the single unprocess frames as a reference for you.

madwayne
22-05-2012, 07:06 AM
Good first effort Jon.

As far as dark site close to Sydney go have you considered joining the Sutherland Astronomical Society (SASI)? $50 per year is a small price to pay for access to a semi dark site at Waterfall on new moon and 3rd quarter weekends as well as our dark site out at Bargo on new moon Saturday nights. We also have two member only star parties at Mudgee (weekend after Easter) and Wooton, near Taree, about 6 months after Mudgee in the September/October school holidays. The beauty of joining a club is sharing the night sky with other members and looking through their telescopes, picking up tips and tricks and also safety in numbers is valid around Sydney.

If you require more info you can pm me or visit SASI's website www.sasi.net.au (http://www.sasi.net.au).

Wayne

loki78
22-05-2012, 01:51 PM
I have joined both Sutherland and the NSW one but due to working shift work (and a lot of it), I've been to only one Sutherland meeting, when they had their trivia night end of last year and no NSW ones.

So things are a bit harder for me :shrug:

cjpops
22-05-2012, 09:26 PM
Thanks for uploading your pic before post Jon, now I can see what to expect before stacking in dss.

Curious, i got a very bad noise and over expose with iso3200 with my canon 600d. Are you working with raw or jpeg with long noise reduction? And was this taken far from city lights?

Cheers

joecool
22-05-2012, 09:54 PM
Craig, have a look at http://www.dpreview.com/reviews/canoneos600d/10
Have a look at the 2nd chart which shows ACR (the raw images). Only look at the left hand column and especially the 2nd box down - the black box. Hower your mouse over the ISO numbers along the bottom of the chart to change the ISO for that one box. You will note that the best noise for this camera is at ISO400. At ISO800 the noise goes up, and beyond ISO 1600 it is far too noisy. For astrophotography you can stretch the data out of the image with software later, and freezing the shot with a high "ISO" number is not a requirement. It only adds amplifier noise in camera. ISO does not mean the same thing as it did with film. And it is mostly the manufacturers competing against each other because they want you to buy their camera and not the competitors so they will say "our camera can go this fast". Some of the noise can be smoothed out with blurring or Noise Ninja, but why do it in the first place? It's OK until you want to print large with your better shots...

Oh, and work with RAW, not jpg, or you loose all the bit depth you've just gained and depending on processing, all the stars will look the same brightness!

I'm not sure about long noise reduction in this camera, but with many cameras the onboard noise reduction eats the stars thinking they are hot pixels or noise and also most cameras do noise reduction by taking a 2nd exposure with the shutter closed and subtracting it in-camera. Best to take RAW images and also take dark frames with the lens cap on and let the stacking software deal with these later. The software will average the dark frames crating a master dark which will be applied to each light frame. this is much better than letting the camera do it's own "dark frames" which only add more noise.

Mark.

loki78
22-05-2012, 10:49 PM
Yeah what Mark said about the Canon long exposure noise reduction. I don't use it, i shot all my darks at the end of the session and subtracted them myself.

I ended up shooting those at Voyager point (that's what my gps said anyway) as I was driving aimlessly around for somewhere dark(ish) as it was windy as all hell at Stanwell Tops so i drove inland.

It's basically near Holsworthy, so it's not right in the city or anything, but still was surrounded by street lights and what not anyway.

cjpops
23-05-2012, 08:48 AM
Thanks Mark and Jon for the info, I attempted another go this morning and managed to achieve a much better result than the last :thumbsup:.

This was done with the jpeg files via deep sky stacker (will try the RAW files tonight)
I just need to get around the noise issue and that link you sent Mark is very helpful - thanks again.

115696

f3.5
18-55mm
ISO800 (will do a ISO400 next time)

joecool
23-05-2012, 09:49 AM
Craig, what exposures have you used and how many frames? Jon has minimized the red and blue splotches which are very evident in the bottom right hand corner of the images (where the skyglow gradient is the worst). Cooling the camera will fix this :D

Well, without cooling - longer exposures and/or a bigger piece of glass to capture as many photons as you can to improve on the signal to noise ratio is the trick. Dithering can help too (bumping the camera off target by a tiny amount between frames. Noise internal to the camera is then moved about over the final image, but because it only occurs in one frame in that position and not all the frames, the stacking software rejects the noise. It's like magic.)

All is not lost though. A quick process with Noel Carbonis Astronomy tools cleans up you image a bit, and this is real cheap software. I have binned the image with Nebulosity to remove the grain (possibly from jpg compression?)(with the original files I would not do this except for web posting as you lose resolution for printing), then ran Colour Blotch Reduction, then ran light pollution removal enhanced flatten, then Auto Tone, Auto Contrast, Auto Colour. Then jiggled the colours with Colour Balance to line up the histogram R, G and B. Then Deep Space noise Reduction. Then Auto Tone, Contrast, Colour again.

Mark.

cjpops
23-05-2012, 10:23 AM
Hi Mark,

Whoa.. what a huge improvement you've made with the Carbonis Tools.. I was aware of the noise and the red hue and figured this might be due to the light pollution (i'm about 30kms from Melbourne) but you simply got them removed.

I had no idea the camera can heat up..

I might purchase these carbonis tools - very handy to have.

The images are all 15secs long exposure, one after another straight away.

I've stacked 15 images and 15 dark images (all jpeg) into DSS then matched the colour graph.. didn't play around with the luminosity as i can't seem to get the hang of it.. just exported it .tif format and then played around with the levels in photoshop.

Will post again with a new result if the sky is clear tonight otherwise i'll play around with my RAW files from last night.

Thanks again!! :)

loki78
23-05-2012, 03:33 PM
I trekked out to Stanwell Tops last night about 2am, 5degrees to have another go. Unbeknownst to me, my gf had used my camera, not told me, and changed from Raw+JPEG to JPEG only. At 2am I didn't even think to check this so everything is JPEG only and the effort largely a waste.

Still, i will have a bit of a play with them tonight at work and see what I can drag out of it.

I did find that in no/low wind conditions Stanwell Tops is a reasonable spot, being only a 30min drive at that time of night and the fact that someone has 'taken out' the bright single light at the north end of the car park.

Upon pulling up in the carp park, I was gretting by about 10 deer grazing on the grass right in front of my car. Good spot.