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Hello Journeymen.

I finally managed to get out last night to download some much needed data from the sky.

Because the temperatures are so high at the moment (15C) and the nights are only dark for about 3hrs, I decided to go for something easy.

M13 is great because it is big and bright, so not much aperture or exposure time is needed.

I went for a simple set up as all my kit was lying packed away in my office.

Setup was my 80ED Frac on my EQ5Pro, with a Celestron 6.3 focal reducer. This made the scope a F4.7. (pretty fast and wide)

Next I did polar alignment and kicked off APT to take 30 pictures at 90 seconds, with 90 second delay. (keep the sensor cool reduce noise.)

Started the process at about 12:00 and went to bed, when I woke up this morning, APT had taken only 18 lights as clouds had rolled in.

Anyway, here are my efforts, post DSS for stacking, PS5 for gradient and curves and Image analyser for noise reduction and local contrast.

M13_Hercules_Crop_IA.png

I hope you all enjoy and any feedback on the image is welcome.

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Hello Journeymen. I finally managed to get out last night to download some much needed data from the sky. Because the temperatures are so high at the moment (15C) and the nights are only dark for abou

Thanks to all that have followed this thread so far. Anyway, I was bored trying to process this further yesterday, going round in circles and not sure how to post process it to get more detail out. I

I won't mention all the things I am jealous of in Thailand!

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Thanks for the replys. I did notice the small galaxy next to the herc, thanks for pointing out the name.

I tried to keep the colours natural.

Has anybody else got experience use half iso or multiples of 160? I did this at iso 1250 instead of 1600 as it produces less noise on a hot night.

This seems to have reduced the noise although I have reduced the exposure times as well.

Any thoughts?

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I like the way it looks to have some nice depth to it with M13 set  deep in the back ground, I know nothing of photography and less of astro photography  but I like that.

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I like the way it looks to have some nice depth to it with M13 set  deep in the back ground, I know nothing of photography and less of astro photography  but I like that.

I know what you mean when I look at it now I can see how the glob is further out than the local stars.

By the way, this observation has nothing to do with photography, but rather a scientific fact that you are observing.

This is a globular cluster of stars  that pre-date our galaxy, ie, the stars are phase 1 stars that are really old from the big bang.

They orbit our galaxy in the same way that a planet orbits the sun, except our galaxy due to gravity, eats them from time to time.

In this picture we are looking through the field of nearby stars (20 to 100 light years) that are in our local arm of the galaxy 

at a cluster of stars (about 300 000 of them) that are about 25000 light years away.

It is a bit like looking through a window with grains of sand on it at a ball of sand far off in the garden.
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Thanks to all that have followed this thread so far.

Anyway, I was bored trying to process this further yesterday, going round in circles and not sure how to post process it to get more detail out.

I started processing it using drizzle and it looked good, but not anything better than the first picture.

The only way I could improve on this picture, which is really a matter of taste, was to go deeper.

So I decided to brave the hot summer evening a second time in a row ... because the mount was still outside and fully aligned.

While I was killing time waiting forever for it to get darker, I decided to put the finder guider on and to get the guiding up and running.

Set APT software to get another 32 x 90 second subs.

I used the option to dither the subs. (move each sub by a couple of pixels) as I wanted to use

- Capa sigma stacking - reduces noise as it clips pixels that are not on majority of images.

- 2x drizzle - developed by nasa to increase image size / quality by using slightly different images.

I have re-stacked the previous subs and the new to get 49 subs (7x7 noise reduction.)

Enough banter here is the new Narrow deeper view:

post-32740-0-70393100-1404249087_thumb.p

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Oh man that's pretty! I really need to get saving for a GOTO mount and DSLR!

Thanks, I must say it has come out better than I was expecting.

BTW, its not GOTO that's important, it needs to be equatorial (the one with weights) and it needs to have motors.

Also your scope must be fast or below f8.

So that you can keep your exposure times down.

Making every photon count is a good read to teach the basics.

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Wow worth the effort that looks like is straight out of a magazine. The star colours looks really nice.

Thanks, although these have far to many faults for a magazine. Unless they ran a article on targets for noobs :)

Edit: hint hint to any magazine scouts.

Edited by Christopher Davenport
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Thanks, I must say it has come out better than I was expecting.

BTW, its not GOTO that's important, it needs to be equatorial (the one with weights) and it needs to have motors.

Also your scope must be fast or below f8.

So that you can keep your exposure times down.

Making every photon count is a good read to teach the basics.

Thanks bud, got a copy coming but gonna be a while before I make full use. Got a fair bit of saving to do before I can afford to motorise and will probably have to upgrade to either an HEQ5 or AVX mount anyway. That's for the future. At the moment I'm just starting to experiment with using a compact digi camera to take eyepiece shots/movies for stacking. First attempt at Saturn not great but have plenty of time and settings to play with to keep me going while I save.

If/when I ever produce a shot like yours I'll be a very happy bunny!

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Thanks bud, got a copy coming but gonna be a while before I make full use. Got a fair bit of saving to do before I can afford to motorise and will probably have to upgrade to either an HEQ5 or AVX mount anyway. That's for the future. At the moment I'm just starting to experiment with using a compact digi camera to take eyepiece shots/movies for stacking. First attempt at Saturn not great but have plenty of time and settings to play with to keep me going while I save.

If/when I ever produce a shot like yours I'll be a very happy bunny!

You should experiment with a webcam and a Barlow to get good pics of planets as they don't need good tracking.

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I would, but that means buying a webcam and a new lap-top. I can't use my scope at home (living in a flat is a mare for that) so have to go out. That means no mains powered kit and my lap-top is too old and knackered to last more than about 20 mins on its battery.

All good things come to those who wait however and, although I'm investing in visual observing upgrades as soon as I can afford them, I have enough patience to wait till I've saved enough to do things properly before I spend on imaging gear. Getting some nice shots of the planets and the moon would be nice, but I'm ultimately aiming at DSO. My plan (subject to change/budget etc) is to get an HEQ5 or AVX mount, power supply and modded DSLR all together when the budget allows. In the mean time I have some time to experiment with my compact and a mates DSLR (and my Baader 2.25x barlow with t-thread) to get eye in for the big investment. As there's only so much I can save each month anyway, it'll be a while whatever I do!

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