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M13 basic test shot


squeaky

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Hmmm... my first attempt at a DSO and it turned out that my alignment on my dob wasn't exactly perfect and I had to limit myself to 10 sec subs. I wanted to know what sort of standard I could get as a base to work from, so potted 15 subs and then hit DSS and processed with PSP. No darks, bias or flats - and a minimal number of short exposures; and it's not too shabby for a first go.

Here's the link to the master tiff file and do please feel free to have a go at it and post your results so that I can see what decent processing skills can get:-

www.squeaky.org.uk/astro_shots/m13/autosaveEmbedApply.TIF

And the processed result:-

m13testSGL.png

So... 70 or 80 times as many subs, plus darks, bias and flats; not to mention taking more care over alignment and I might get something quite good! :)

Anyway - if you'd like to play with the tiff file and post your results I'd be really pleased to see them. Honest :)

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Much better than mine sir ,

I got an orange cluster ?

Maybe need to start that post processing lark soon............. :grin:

Thank you kind sir :)

Orange? Definitely need to start your apprenticeship in The Dark Art then :)

It's amazing how much post processing can bring out.

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Thanks :)

It looks as though the weather will allow me another go tonight.

What I'm finding is that if I align the scope using an EP - when I replace that with the camera, which is hanging off the end of a LOT of tubing...

fitcameratobarlow.png

I'm pretty sure that it hangs down at an angle because my target is not just off-centre - it's completely out of view. So tonight I'm going to do my alignment USING my camera's live view. That should help with targeting and tracking. I hope! Oh! And guess which muppet left the view-finder on the camera instead of replacing it with the blank!

Given how "small" M13 is in the image frame I might have a pop with my x3 Barlow and maybe even my x5 Powermate. Then... there's the option of using EP's, which will probably turn out to be a whole new ball game. And with better tracking I should be able to take longer subs. All told DSS used 1min 50secs worth. Barely two subs for folks with an Atik and/or an equatorial mount. As a first effort with a DSLR on a Dob I'm pleased with my start.

So another twenty or thirty viewing nights and I might just finish up with an M13 worth bragging about :)

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Hi Squeaky,

I had a similar problem to you with my 3 screw service attachment on my SW 80 ED Pro.

With my canon and adapters hanging of the back it brought everything out of centre framing

so I purchased the baader clicklock attachment, you push the camera in with all its bits

turn to lock it, does'nt move a bit. They could very well do something similar for your scope.

BigBlueOne.

Your M13 is a smashing image by the way, sorry forgot to put that in.

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Hi Squeaky,

I had a similar problem to you with my 3 screw service attachment on my SW 80 ED Pro.

With my canon and adapters hanging of the back it brought everything out of centre framing

so I purchased the baader clicklock attachment, you push the camera in with all its bits

turn to lock it, does'nt move a bit. They could very well do something similar for your scope.

Um... if it replaced all my bits and allowed me to get a focus I'd try it. Nikons seem to be a lot more awkward than Canons to get a focus. I'll have to start attending star parties and see if I can borrow one to try :)

Your M13 is a smashing image by the way, sorry forgot to put that in.

Thanks :)

I initially ran DSS purely on defaults. Now I've had a tweak and got a much better end result from DSS in the TIFF, but can't for the life of me remember exactly what I did when processing the first one! I can get close with just three "operations"... so definitely better and easier with this second stack. Note: to self - post the 2nd tiff after your nap! :)

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that's a very good start

I'm still waiting for the superprocessors to show me what it really looks like :)

In the meantime...

take3SGL.png

There's a tad more noise in this one, but I haven't lost any of the stars either. I can't find a way to lose the noise without losing stars.

Well, there IS one way...

Lots more subs and darks and things :)

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Hi Squeaky,

Have you thought about Astronomy tools for Photoshop, they really are

a great set of actions with a couple of noise reduction tools that clean

images up a treat. And I do believe only $20 so not to badly priced.

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Thats a really nice up close shot Squeaky.

Thanks :)

It's not actually a close up as such. Taken at Prime Focus with a 2x Barlow. I should easily be able to keep it all in frame on my 3x (yet to be tested) and possibly on my 5x Powermate.

Maybe it's just my eyes but the last version looks more 3D than the others - actually looks globular.

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Good grief! You even managed to keep the "crosshairs" on the brighter stars!

More to the point - that's with my first attempt at DSS and I think the second one is better (which is the one used for all the later images).

PSP has a "Colour Replacer" tool and I have found that if I use the colour picker and right-click in a noisy area and left click somewhere clear - just a single click with the tool pretty much wipes it out...

marks_m13SGL.png

OK... I'll make some darks, flats and bias today then run it all through DSS again and post the new tiff.

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The most amazing bit to me is how mark managed to really keep the stars as you see them, diffraction from the secondary holders and all.

It really does point up the lesson that there's loads of data in even the poorest of pictures that can, with skill, determination and knowledge of the game, be recovered to produce amazing stuff.

In fact... here's one of my single .jpg's... http://www.squeaky.org.uk/astro_shots/m13/DSC_0633.JPG

And from just 15 of those 10 sec subs (DSS used 12 of them) we got what you've seen.

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Had a crack at it for you Richard needs darks flats and bias to cancel out all that noise but its a good start

Hokay Mr Smarty Pants :)...

Here's the tiff from DSS with added darks, flats, and bias (10 of each)

http://www.squeaky.o...3_DFB_apply.TIF

I'm REALLY looking forward to see what can be done with this.

EDIT: Oh, and could you do me a favour, please? Frame the globular the way I've done in my posts with the centre of the globular 2/3rds to the right and 2/3rds up. Cheers :)

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There you go Richard, I think you could benefit from taking 60-80 subs at 40 seconds each for this one and combine that with 60 darks flats and bias shots also make sure your focus is really spot on to resolve the stars in the core of the cluster.

10 darks is not enough you need a minimum of 30 to smooth out the image. And take the darks the same night, flats and bias can be done the next morning :smiley:

Richards%2520m13%25202.jpg

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Blimey - how the devil are you keeping those diffraction patterns on the brighter stars??

As for 40 sec subs - I'm on a dob mount - so I'm going to have to work very hard on alignment. 10 secs was the longest I could go that night without getting trails. So I went with an ISO of 3,200 which is why there was so much noise.

No chance of viewing last night - next one is hopefully Monday night and you can be sure my target is going to be M13. I've been learning bucket loads of stuff over the last couple of days so I'd really like a good data set to work with. And yes, I'll do the darks that night too. :)

I don't know quite what I did differently in DSS with that second take but most of the brighter stars have a fainter smaller "echo" at about one o'clock. If I try to lose that echo I also end up losing a lot of genuine faint stars.

Anyway - given the minimal data set we were working with I reckon that's one heck of a good result. I was SO_ooooooo disappointed when I saw my first jpg. I can't believe how much can be teased out a set of them.

Thanks a lot :)

Here's my last pop for this data set - roll on the next good sky.

take5SGL.png

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