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Totally Bodacious Dude! (M81 in LRGB)


PhotoGav

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Well, we seem to be firmly in the season of the M81 / M82 area and I have joined the party! Here's my attempt at M81, Bode's Galaxy:

post-29321-0-45078500-1424730533_thumb.p

Celestron EdgeHD 800 with Reducer and QSI-683.

L = 14 x 1200s

RGB = 6 x 600s each

TOTAL = 7h 40m

Fairly happy with this one, though I do have some problems with star alignment in the RGB layers. Not sure where that is coming from - could it be collimation or is it something to do with orthogonality of the chip or is it simply poor sub alignment in Nebulosity? Still not totally convinced that the Edge is the best scope for DSO, but it's all I've got for this kind of target! Any ideas on what would be a better 2m + focal length DSO scope greatly received.

My plan is to add M82 to the left of this, we'll see if I am up to the challenge...

As ever, all thoughts and comments greatly received.

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Very nice, tricky scopes to image with, focal reducers cost a lot and still make the scope a little slow, hyperstar looks very interesting and make these scopes mega quick for imaging but again cost a lot plus using a qsi 683 with one on the hyperstar unit isn't ideal.

This is probably why people love short length refractors as they need virtually no colimation and are small and easy to use.

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Thanks folks.

@Zadoq - these slow optics take an age to over expose!

@red dwalf - yup, I prefer my 'frac really. Wondering whether an RC would be easier for long FL stuff? I don't have any urgency to try out Hyperstar with the Edge!

@michael - you are right, this is a bit too yellow. I think I was just trying to get some colour, any colour into the image, but I've over done it. A revisit will be forthcoming! Thank you for pointing it out.

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I agree about the yellow - You have some good detail in there but it is rather brown / yellow looking. May be able to fix it easily with a quick colour balance with little reprocessing.

A 2m galaxy scope? You're looking at either a large RC (8" is only 1.6m) or perhaps a nice Dall Kirkham. For all of these you'll have to also look at a mount upgrade for sure.

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Thanks Sara, I will be having another fiddle with this later today and will try and sort the colour out. The trouble is that my processing always pushes these long fl images to a browny yellow hue and very little blue. I wonder why?

Interesting ideas about the scope alternatives. Biggest issue is the vast amounts of cash required to go down any further route really... Would be lovely, but I will need a permanent home for anything heavier than my current set up. I will have to keep dreaming for now. Perhaps the Edge isn't that awful after all!! :grin:

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Hi Gav, a nicely detailed image you have there. Well done. I would agree with the above regarding colour but I also note a bit of vertical banding. I'm interested in this as I have seen the same with my own 683 camera on a couple of occasions and have recently been in touch with QSI about it. As of now they report quite a number of there customers are seeing this banding in their calibration files and they are looking into it. Have you noticed this yourself?

Pete

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Hi Gav, a nicely detailed image you have there. Well done. I would agree with the above regarding colour but I also note a bit of vertical banding. I'm interested in this as I have seen the same with my own 683 camera on a couple of occasions and have recently been in touch with QSI about it. As of now they report quite a number of there customers are seeing this banding in their calibration files and they are looking into it. Have you noticed this yourself?

Pete

Thanks Pete - I will be revisiting the RGB portion of this image soon! As for the banding, yes, I noticed it on this image for the first time. I even ran Noel's Action to remove vertical banding, but it didn't work... I'm very interested to hear what QSI have to say about it and if you have an ongoing discussion with them and would like to add this image as evidence, please shout.

Thank you @ Sand Dune!

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post-29321-0-41577600-1424805076_thumb.p

I have toned down the whole thing a bit, but especially the spiral arms. I adopted the subtle approach, but hopefully with some effect.

I have been looking at this so long now that to me it is no longer a galaxy, I officially rename it 'The Fried Egg'. 

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Thanks Chris & wavydavy.

You are right Chris, this is still a bit muddy. I'm not sure quite what to do to resolve that. The histograms show equal colour peaks, so it should be balanced, but it isn't? I wonder if I should gather more blue subs than red and green? If so is it simply a case of capturing more subs or should they be longer subs? So much to learn!

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Like a dog with a bone.... I just keep fiddling. Here is a very dodgy version of what I set out to do with M81 & M82:

post-29321-0-40165600-1424819816_thumb.p

So, theory proven. Time to go back to the start, process M81 properly, sort out the extremely dodgy stars to the left of M82 and make a pleasant version of this image!

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The third versions looking better Gav :) I can see your battle of trying to get more blue in the galaxy without giving a blue cast to the star field. I think the third version is a good compromise, and your galaxy detail is stunning!  

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Thank you for the feedback, I feel like I am making some progress with this image and that is thanks to the comments that I have received.

I was considering the EdgeHD 800 with AVX mount due to it's portability but was advised against it in terms of DSO photography due to long focal length... but I see that it does produce amazing photos when you apply proper skill to it :)

Thank you, you are too kind! It is possible, but the advice you were given was probably correct and I certainly wouldn't want to start out with this scope - a short 'frac is much much easier! I am yet to really suss out the RGB side of it, though I am pretty happy with the luminance and narrowband data that I can collect with it.

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Thank you for the feedback, I feel like I am making some progress with this image and that is thanks to the comments that I have received.

Thank you, you are too kind! It is possible, but the advice you were given was probably correct and I certainly wouldn't want to start out with this scope - a short 'frac is much much easier! I am yet to really suss out the RGB side of it, though I am pretty happy with the luminance and narrowband data that I can collect with it.

Yeah, I think the advice was probably more of "not recommended to start with" rather than "not suitable at all" now that I think about it. Might not have a choice as the setup is supposed to be a gift and since I live in a flat, on the 3rd flor - portability is quite an important aspect for me - but we will see. If I end up getting the EdgeHD, would you mind sharing some advice at some point ? :)

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Yeah, I think the advice was probably more of "not recommended to start with" rather than "not suitable at all" now that I think about it. Might not have a choice as the setup is supposed to be a gift and since I live in a flat, on the 3rd flor - portability is quite an important aspect for me - but we will see. If I end up getting the EdgeHD, would you mind sharing some advice at some point ? :)

If you do go for the Edge, I can of course try and answer questions / offer some advice!

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