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Have mercy!!!
http://www.boltonastro.co.uk/forums/viewtopic.php?f=8&t=523
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Author:  jMcConnell [ Mon Apr 29, 2013 8:39 pm ]
Post subject:  Have mercy!!!

Okay,

After some months of wondering "should I, shouldn't I?" I have finally decided to post my first attempt at a picture - I am secretly chuffed to bits with it but welcome any comments.

This was taken with a 6” skywatcher reflector on a EQ3-2 with the single axis motor which allowed a 60 second exposure (I think it was 60). Big problem was the eBay camera bought for my new hobby, a canon 350d. No doubt a great camera but as I have learned, without the live view feature it is a bugger trying to focus a 1/4” viewfinder image. I've also since bought a light pollution filter but not the time to give it a try.

All in all, I think my 'entry level' ebay purchases may not be upto the hubble/herschel quality I was expecting – funny that.

Any advice is more than welcome!!!!!!!!!!!!!!!


John

Attachments:
Orion.jpg
Orion.jpg [ 71.8 KiB | Viewed 9016 times ]

Author:  dean_kos [ Mon Apr 29, 2013 9:08 pm ]
Post subject:  Re: Have mercy!!!

Hiya John, firstly well done on your first capture, nice image of the dumbell nebula that ..... 8-) Did you polar align properly ? and is your mount/scope kept nice and stady during the exposure ? there is obviously either bad polar alignment or movement in the whole setup which is causing the 'long stars' and smudged image.
I suspect it could be you actually pressing the button on the camera to start/stop the exposure...... if this is the case then you need a timer with a push button fire that will enable you to control the camera without actually touching it and hense preventing all movement and sharpening up your image. If you are already using one of these then check the first two points I made above......
The way I focus is to take several shorter shots, say, 10 seconds each, whilst moving the focus slightly on the scope. Check each shot on the back of the camera (zoom in on the stars) and see which is best focus/sharpest.... I will move either side of sharp focus and keep taking the short shots until I'm happy I'm at the sharpest point, then start my exposures. Alternatively, you could grab a bahtinov mask focus aid and attach this to your scope, (see threads on forum about these) but personally I dont have one.
My canon has 'live view' but to be honest dont feel as your missing out not having this feature as its very rare I use this for focusing unless there is a huge bright star in my field of view or a planet.
Nobody should be able to get a chrystal clear pin sharp image on there first attempt. it just dosn't happen as It's a hard thing to achieve, in fact you probably wont be completley happy with your next 100 images but it's the challenge of the one stunning image we strive for that keeps us trying, so keep it up and well done....

By the way, I know its orion nebula, just my daft sense of humour :lol: :twisted:

Author:  jMcConnell [ Mon Apr 29, 2013 9:17 pm ]
Post subject:  Re: Have mercy!!!

Hi Dean,

Yip, i had polar aligned and I was using a mirror lockup and shutter remote which means - I'm pants at polar alignment.

:oops:

john

PS - I can see this becoming an expensive hobby

Author:  cstone [ Tue Apr 30, 2013 6:42 am ]
Post subject:  Re: Have mercy!!!

This was taken with a 6" Newtonian. It's not that good example. It would of been better if I had a light pollution filter.

But then there is the image processing :roll: . Flats, darks, biases. A wavelet here, a wavelet there. Do I apply a filter with Photoshop or add a few de-fraction spikes that didn't exist in the original image. For someone to then say "your not in focus".....it goes on and on and on.

Either way it was 14 x 20 second frames stacked in Iris. But take Deans advice.

Attachments:
File comment: 14 x 20Sec ISO 800 no frills setup
Untitled.png
Untitled.png [ 814.64 KiB | Viewed 8991 times ]

Author:  bholmes [ Tue Apr 30, 2013 8:37 am ]
Post subject:  Re: Have mercy!!!

I would have been pleased if my first image looked like that. Mine was of Jupiter and looked like a searchlight in space it was so over exposed.

M42 is a tricky target, east to find but challenging to photograph as the central Trapezium is easily over exposed. Carl's stacked images of shorter exposure gives a better result but that comes with practice, practice, practice and lots of patience.

Good start though

Regards

Author:  bbones [ Tue Apr 30, 2013 9:20 am ]
Post subject:  Re: Have mercy!!!

Well the answer is yes. By showing what you have done will help us put you right.

This is not easy and there are a lot to master, I have found polar aligning the EQ3-2 very difficult and has a major effect on the results.

Have you tried mounting your Camera on the mount just using the lens that cam with it?

I use a Galaxy Tab using DLSR controller (Andriod free softawre) connected to my 600D and spend time getting the focus right before any imaging run and still get it wrong. I also control the camera with the same software

As per the other comment it's a good start and you can look back and see your progress

Regards

Bill

Author:  rwilkinson [ Tue Apr 30, 2013 9:57 am ]
Post subject:  Re: Have mercy!!!

Well done John, and thanks for posting your image.
I think that you did well to catch M42 so late in the year, but reckon that by the time it's visible again in the Winter sky you'll be able to get a much better result.

By the way, after a little work in the "digital darkroom", I managed to make some improvements in your posted image using IRIS:
Attachment:
m42_john.jpg
m42_john.jpg [ 46.23 KiB | Viewed 8982 times ]

But I'd say that you're making life difficult for yourself starting with such a long focal-length (is it 750mm?) - remember Dave Walker's Rule: "pain is proportional to the square of focal length" - by this reckoning, if you started with a 135mm lens it would be thirty times easier!
And we do have such an item in our loans pool (http://www.boltonastro.co.uk/forums/viewtopic.php?f=17&t=203) - (contact Dean if you'd like to borrow it)

Now how did you do your polar alignment?
Does your mount have a polar-scope, and if so is it properly aligned with the polar axis (you should check this on a terrestrial target, such as a distant chimney-pot or TV antenna)? And did you use the Polar Finder program (http://myastroimages.com/Polar_FinderScope_by_Jason_Dale/)to work out exactly where to position Polaris in your reticule?
Otherwise you'll need to use the time-consuming declination drift method.

Focusing should be first optimised on a nearby bright star (e.g. Betelgeuse), using a Bahtintov mask (http://www.boltonastro.co.uk/forums/viewtopic.php?f=4&t=39). Even without LiveView, if you connect your camera to a laptop via the USB lead you should be able to view the frame you've just taken on the bigger screen (and zoom in).
Alternatively, I've had success with my Pentax K110D and the BAS Canon 300D simply using a right-angle magnifier (http://www.boltonastro.co.uk/forums/viewtopic.php?f=4&t=425) on the viewfinder, and focussing the 'scope to reduce the bright star to the sharpest dot.

Author:  Amartin [ Tue Apr 30, 2013 12:53 pm ]
Post subject:  Re: Have mercy!!!

For the cost of <£10 you can get a bhatinov mask off ebay & solve all your focussing issues. I bought one for my C6 in Kelling Heath last year (for a £5!) and ive got one for my little apo; I find them invaluable - especially as your mince pies can convince your brain that something is in focus when it actually isnt. The bhatinov mask doesnt lie. Its especially useful if you dont want to go down the route of dragging your laptop outside as well.

To be honest, you dont need to worry about focal lengths and all that caper - its too early (in astronomical growth terms) for you to be worrying about that - all you need to concentrate on at this stage is in the book of Kos:
polar alignment
polar alignment
polar alignment
Dont touch the scope at all. (Dont even let a friend kick the mount after youve setup...)
From the gospel according to Wilkinson:
You'll struggle imaging through that scope because its not really designed for it (paraphrased of course!)
Weve all been there at one point - dancing round the garden with wild abandon because we recognise what it is that weve captured on the camera & it loosely resembles what was in the sky. Youve taken your 1st massive step on a very long & difficult road.
Keep going & dont listen to anyone that says your images are pap - especially if you like them!
Cheers
Andy

Author:  jMcConnell [ Tue Apr 30, 2013 5:21 pm ]
Post subject:  Re: Have mercy!!!

Gents,

Thanks for your comments, they are well received - especially Andy's one about me dancing round the garden. I was surprised to find my better half did not share or understand the giddiness and glee I was feeling.

I took it back in february so it has taken a while for me to pluck up the courage to share - thanks for not laughing!! Bernie, this is the picture I'm willing to post - there were many others that looked like a child had gone mad with a white crayon but I am pleased I have a starting point to look back on.

Dean / Ross / Andy, the polar alignment was done by centring polaris in my scope - not ideal, far from it as I realise now. I'll invest in the add-on that skywatcher do and thanks for the link to the alignment software.

Also thanks for the advice on using a mask and especially checking the frame for focus - a bit of a 'doh' moment as to why I hadn't thought of that!!

Bill, sadly, I bought the camera as a body only so don't have the option of using it on its own. I'll see if I can get the DSLR controller for my phone, I think she'll kill me if I suggest a tablet plus all the other bits on my wish list.

Carl, thanks for your pic, as others have said it may take a while to get there, but get there I shall. I had somehow got it into my head that long exposure was the be all and end all but clearly not. Also I need to get my head around flats, darks etc. I'm a computer nerd but have no idea what a defecation spike is :(

And Ross, I am in awe at what you've done - it just goes to show you really can polish a t**d!!

Thanks guys - now if only the clouds would clear..........

Author:  dean_kos [ Tue Apr 30, 2013 5:45 pm ]
Post subject:  Re: Have mercy!!!

To be quite honest with you John...... No, you really can't polish a t..d, and this thread just proves it I'm afraid.....
If your raw image is bad then the final result will be bad, only made worse with trying to over process the errors out....believe me mate, I've tried time and time again and it don't work !!
Spend more time than necessary learning how to correctly polar align (not by centering polaris in your scope !! :o )and have another bash my friend, you will see the difference immediately .... You only need to glance at the image Carl posted above to realise that it is possible with your setup when you spend some time getting the basics right....

Ps, it's defraction spike mate, not defacation spike :lol: and they are the nice fancy spikes surrounding bright stars in a final image..... They can be captured using certain techniques or added in using software....

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