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ribuck

2nd ever attempt at imaging

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Hi all,

This is only my second ever attempt at imaging. My first way M82, so i decided to go with M81 as my second.

I've processed it as best as i can.

It's not a great image as it's low res, as i only have a MX916 and guide with star 2000 so loose half the sensativity straight away.

This was taken through a 8" newtonian @F5 with a Starlight Mx916, guided with Star 2000.

LRGB 10x 2.5 mins each at 1x1 binning.

Would love to hear peoples comments.

The main pic has been converted to jpg, but I have also attached the 16bit tiff. I would love to see the results of an expert processing my Tiff to see how far off i was.

Rich

post-13727-133877371788_thumb.jpg

post-13727-133877371794_thumb.jpg

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Thanks, I'm pleased with it. Just wishi had a high res ccd instead of the old low res Starlight Mx916.

Sigh....to have one of those lovely new 8.3mp ccd's....:)

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Thats a great image especially if its only your second.

Cheers

Neil

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Thanks Neil. Yes it's only my second image as i've wait for 6 months to get a night that stays clear for more than an hour.

Im just hoping some kind imaging expert my try their hand at my raw tiff file and see what the come up with, as i'm keen to see how different it would be to my own processing.

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I think that's really nicely presented/composed too, your 2nd image ??:)

I think I'll quit ! :D

( nice clear sky but gusting like crazy -hence not too chuffed ATM )

Well Ribuck, let's see more.

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That's brilliant - and if it really is only the 2nd effort of a newbie, amazing! Keep working at it and we should be seeing beauties from your direction.

How was it processed? If, as I'm guessing, the 'spikes' were added with Noel's tools, try making them a wee bit less prominent? Just my opinion, mind. And you could see if you could tackle the star haloes perhaps, with the same tools. Otherwise, can't fault it.

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Nice image my second was rubbish compared to many you see around, but even being able to tell what it is, is a good image. When you start as there is so much to learn concidering how complicated the telescope setup gets and how accurate you have to be

So a great image for your second well done.

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Thanks guys. It's certainly a steep learning curve. Pete, yes you were right, i did use someof noels tools to help me process, but had to do the initial levels, curves on my own as the original tiff image just looks like a white pea in a black sea.

Now, does anyone want to lend me a nice shiny high res ccd to see if i really can do a lot better...:):D

Just for the sake of comparison, this was my first ever attempt at imaging back in Nov 2008.

post-13727-133877371798_thumb.jpg

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I think you are well on your way to producing some really nice work , excellent stuff there, well done , lets have more

Rog:)

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I'm with Rog...you have some great material there, very well captured. :)

I prefer the processing on M82. On this image you haven't made the background completely black, and it looks more natural for this.

If something is completely black, then all information in that region is lost, and can't be retrieved later in processing.

On M81, you've pushed the background into the black point over half of the image.

The galaxy itself looks great though :D

Get hold of 'Gradient Xterminator'. It will help you to get a flat background which will then be much easier to adjust with levels and curves.

Both images are great though, especially as you've hardly done any before, much better than my early attempts :)

Graet work Rich. Looking forward to seeing more, if we ever get any clear nights without a moon, or wind!!

Cheers

Rob

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I also think these are extremely good for first and second images!

Once you get to grips with things a bit more, you will be doing some awesome stuff.

I was gonna have a look at your TIF, but it doesnt seem to be attached.

You can use www.mediafire.com to upload to.

Good work :)

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Thanks guys, nice to hear the comments. Rob, I'll try that gradient exterminator, as i had to make the background quite dark just to get rid of some banding artifacts.

I think i'll maybe try reprocessing the image, as i agree with Rob that it's a little over processed and i think i went a little mad the star diffraction spikes.

Aza, unfortunately the Tiff file is 2.5mb, so too big to upload, so i'be put a copy on my webite, so you can download it you fancy giving it a try.

The link to download the tiff file is here :-

http://www.astrosky.co.uk/images/attachments/GroupX-LRGB.tiff

Rich.

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Rich I couldnt process it any better than yourself.

I am not very good at colour balance, as I use a DSLR and my colours are generally already balanced ok!

I think really you just need more exposure time to improve your image.

52515867.jpg

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Thats a very good start Rich I would agree with Rob comments. M82 looks very good and I would be more than proud for a first image. On M81 the background is clipped heavily and the galaxy has been blurred with noise reduction. I'm sure there is quite a lot of detail to be had from the data you have captured. Considering you have gone straight into LRGB imaging you have captured and combined the data very well.

Regards

Kevin

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Very Nice Rich and Arrans process of the tiff shows theres a fair bit of info in there.

With LRGB you can bin the RGB at 2x2 and get a lot more color in the same time keep the L at 1x1 and spend time working on the L data before you combine the RGB with it...

Peter...

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Hi Arran,

The problem i have is that I'm using a starlight Xpress Mx916 which is a fairly low resolution ccd, and when you use the Star 2000 interface, it uses the same ccd to also guide with at the same time, so you loose half of the data straight away.

So when i do 600 sec Subs, I only really get 300 secs worth of data, as the star 2000 interface uses the ccd haff of the time to guide. The other thing is that my ccd locks up if i try to do binning a 2x2 if it's more than 60 secs. Think i need to consider saving for a new cam.

It's not the best setup, but it ok for a newbie like me until i can afford a better ccd and a guide scope.

I was looking at getting a Qhy9 and a guide scope, but bern can't seem to get his hands on any.

Rich.

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Hi Rich

Well you have a lot of scope (no pun intended!) to get more subs. You have 25 mins per channel, if you get more data you WILL see the image quality grow.

Also the two targets you have gone for are not the easiest of galaxies.

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Arran,

The other problemi have is that where i live, I have limited amounts of time to capture, as it's very very rare that i get more than 2 hours of clear sky before the clouds role in, no matter what time of year.

This is the main reason i want to change my ccd. Plan for the future is to use the Mx916 purely for guiding, and a second ccd for Imaging only. Straight away i will double the amount of data i'm capturing, as i'm not using the same ccd chip for both imaging and guiding.

Add into the equation a very high res cam such as the QHY9, then I can do high levels of binning 2x2 or 3x3, whilst still retaining a high resolution Image.

If i use 2x2 binning i'll capture 4x the info, and couple that with the fact that if i use a seperate cam for guiding, 600sec subs will really be 600secs instead of 300, so basically I double what i'm getting now, so just changing my cam i should be able to get 8x the amount of data in the same time period.

Rich.

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Tried reprocessing the image with a much more natrual look, still prefer my first attempt at M81.

post-13727-133877372057_thumb.jpg

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Rich, I understand the problems you have but based on your M81 I would be wary about binning. It is not all it's cracked up to be and you will lose resolution in spite of most of it coming from the luminance data. Your picture does seem to be weak in colour but I would accept that for now and get more unbinned colour when you can. Although it is nice to get the job done you can get it next year and work on something else for now.

I played with your TIF and attach it below. I cannot see a lot wrong with it, if this is your second attempt heaven help us all in a year or two's time!

Dennis

Edit: looking at the posted version it is too light but does show what dim parts you have caught.

post-15519-133877372063_thumb.jpg

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Dennis,

What did you use to bring out the detail if you dont mind me asking ?

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sorry, I didn't take too much notice. With some of these things it's a bit like driving on autopilot.

Two iterations of levels just using the mid point slider set to 2, no white point moves. Crop, Curves to up the mid range contrast, duplicate layer - magic wand to select stars, select-modify-expand3-feather 2, Control J to copy selection to new layer, high pass set to 8pix on background copy-set layer blend to Overlay. If it looks good switch off star layer and merge visible. Duplicate background again and repeat high pass at 2 pix, switch on star layer and make sure you haven't completely mucked it up before flattening image. Be careful with high pass. Reduce noise with Neat Image.

That's about it. A couple of minutes work when you are into the swing of it. The overriding impression I had of your data is that there wasn't enough of it. Another hour of Lum will make a world of difference.

Dennis

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Now thats superb..

Better than my early attempts. Although you may have clearer sky and you have a faster scope :)

Race ya to the zenith :D

Guy

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Hello Rich,

Here's the result of a play I had with it.

I cropped it a bit, performed gradient removel and noise reductiuon on the background, a few iterations of levels and curves etc. No sharpening.

I got rid of some of the colour cast using a curves adjustment on separate colour channels.

There's something odd happened to the stars, either a mismatch while stacking, or the mount has jumped slightly for a second.

There was a great big blue dust bunny or something in the bottom right. I got rid of that using gradient Xterminator, and removed any background colour variation by selecting the background, and then desaturating it.

The overall impression I got was that, like Dennis said, you could do with at least another hours worth of luminance data, and get some more colour subs too.

Very good image though....you'll go far :)

Cheers

Rob

post-14403-13387737216_thumb.jpg

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