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Tonights Bounty


Paul81
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Hi All,

Had a great evening of observing / video imaging tonight.. would have stayed out longer but tiredness and the cold were creeping in.

All images are captured using an SX Lodestar Mono with my own Lodestar Live imaging software. The images are 30 second exposures, with only live dark subtraction and processing applied (no extended post processing - these are the images I was viewing out at the scope). A (visual) Astronomik CLS filter was fitted to the Lodestar. The scope was running in Alt Az mode.

First up is the supernova in M82 - an easy spot visually and comes out well in the image. I can never tire of seeing this galaxy and M81 together and its an extra treat with the supernova as a bonus.

post-9673-0-77570400-1390515430_thumb.pn

Over to Gemini for C39 - the Eskimo Nebula. Observed visually at 150x and some colour is evident, and also the structure. The structure is much more evident in the images.

post-9673-0-50124000-1390515606_thumb.pn

Next up Taurus for M1 the Crab Nebula. This is a very faint vague fuzzy patch from my skies, with little or no structure evident. The image shows way more detail. I still don't see it as a crab though.. then again I do not in the hardcore deep images either.

post-9673-0-47178100-1390515766_thumb.pn

Final stop is the main man of winter, Orion. What evening is complete without a visit to M42 the Orion Nebula. I can never tire of this object, and it is stunning in the 21mm Ethos. I pretty much always look at it every time I am out. The image is a little over saturated in the core, but I was sticking to 30sec images so here goes:

post-9673-0-60124300-1390515935_thumb.pn

Then quickly up to M78 - not much to see visually, I should probably experiment more with my filters. The image reveals much more, but is some way off the detail of the long exposure folks.

post-9673-0-28449500-1390516033_thumb.pn

Lastly, something I can forget seeing visually from my skies, but an object I find magnificent. Its so darn faint.. this image was live stretch to kingdom come hence shows a lot of noise, but who cares.. its the Horsehead!  :grin:

post-9673-0-06605400-1390516193_thumb.pn

All in all a great evening. I visually observed a bunch of double stars and also the king of planets but no pictures so I won't go into any details!

Hope everyone else had some clear skies tonight and enjoyed what was on offer!

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Hi Paul

Lovely shots from an exciting piece of software! I speak as a Mac user hoping to try it out one day... I'm thinking of plonking my dob on an equatorial platform and then live stacking shortish exposures. Lodestar Live seems to be just the job for that. Is the registration working well?

Martin

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Hi Paul

A great evening and nice to see you out with your scope rather than stuck in front of your computer coding :)

Incredible detail in the Crab nebula considering it's a 30s exposure.

What's your sky like for light pollution? - mind you an extra 2" of aperture and a mono Lodestar will definitely make a difference to my colour Lodestar and C8 SCT!

Here's my M82 from Sunday night (19/01/14) - single frame captured with Lodestar Live at 30 second exposure with the SN there.

M82

Clear Skies

Paul

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Hi Paul

Lovely shots from an exciting piece of software! I speak as a Mac user hoping to try it out one day... I'm thinking of plonking my dob on an equatorial platform and then live stacking shortish exposures. Lodestar Live seems to be just the job for that. Is the registration working well?

Martin

Hi Martin,

Thank you for your kind words. In terms of the registration (stacking) then that is a feature to be added (in hopefully) the near future. I have the algorithms prototyped in Matlab but need to firm up a few bits and then code them into C++ for the app. The images you see here from myself and DoctorD are only single exposures (although I have been collecting lots of subframes to aid development). The stacking will make a huge difference, basically the longer you keep live observing the target, the better detail will build up before your eyes on the screen. The app will have 3 live stacking modes - averaging, median and additive - different algorithms for different targets / situations. Parts of it are actually in there already - as they are common with the focus assist algorithm (star extraction and star quality measurement).

The current program does perform dark frame subtraction, and these are stacked using a rolling median estimator (no need to register these though). I normally take about 10 darks at the start (which I am visually observing), this is then used during the live viewing. The median estimator means you can add dark frames as and when you like, and I found with around 7-10+ exposures it gets to about 1-5% of the actual median value.

In terms of a tracking platform, you will need a set-up which can track sufficiently for the period of time of a single sub. I have been using 30 seconds as it seems a good compromise between the 'live' experience, sufficient time to gather a meaningful signal, and also running the mount in alt-az mode without too many issues. If using smaller exposure lengths then the stacking will help bring more of the object out. The stacking algorithm that will be going into the app will auto reject duff frames - I get about 1 in 10 frames that should be rejected due to excessive alt-az movement.

I am currently implementing colour decoding for the Lodestar-C - once this is complete I will begin adding the stacking algorithm. If you would like a copy of the app then ping me an IM with your email address and I will send you over the latest version (if you don't mind beta testing of course..  :grin: )

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Hi Paul

A great evening and nice to see you out with your scope rather than stuck in front of your computer coding :)

Incredible detail in the Crab nebula considering it's a 30s exposure.

What's your sky like for light pollution? - mind you an extra 2" of aperture and a mono Lodestar will definitely make a difference to my colour Lodestar and C8 SCT!

Here's my M82 from Sunday night (19/01/14) - single frame captured with Lodestar Live at 30 second exposure with the SN there.

Clear Skies

Paul

My skies are not the best, but not too shabby either. I get quite a lot of stray light from neighbours. I have a dark site to go to, but its a hassle packing everything up vs just setting up in the back garden. What are your skies like?

Thats a nice shot there of the SN in M82 too. I am really looking forward to seeing that in colour (hopefully not too long now). Did you use your focal reducer on your C8? My scope is F4.8, so if you are down at F3.3 then you will be gathering data quicker. Although more sensitive, I must admit you (and Nytecam) are really making me think about buying a Lodestar-C too... I feel I am missing out on colour.. especially as I like hunting down the planetary nebulas.

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Hi Paul<br />

<br />

Yes, I used the F3.3 reducer, with the spacing I achieve about f2.8 (like Nytecam) although this results in some distortion at the edges. <br />

<br />

I have the F6.3 which is more forgiving and can be used at a wise range of reduction rates - This is what I used with the INED70 to reduce from F6 to about F4.2. <br />

<br />

My little 102MAK can also be used with all the reducers giving me a choice of focal lengths to suit the target. <br />

<br />

I'm limited to AZ mode and have noticed that the tracking on the minitower is not great and I get a lot of shift between images. 30 seconds seems to be the longest I can achieve. <br />

<br />

Will your stacking algorithm support rotation as well as translation?<br />

<br />

Looking forward to the first release with colour support!<br />

<br />

<br />

Clear skies<br />

<br />

Paul

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Hi Martin,

Thank you for your kind words. In terms of the registration (stacking) then that is a feature to be added (in hopefully) the near future. I have the algorithms prototyped in Matlab but need to firm up a few bits and then code them into C++ for the app. The images you see here from myself and DoctorD are only single exposures (although I have been collecting lots of subframes to aid development). The stacking will make a huge difference, basically the longer you keep live observing the target, the better detail will build up before your eyes on the screen. The app will have 3 live stacking modes - averaging, median and additive - different algorithms for different targets / situations. Parts of it are actually in there already - as they are common with the focus assist algorithm (star extraction and star quality measurement).

The current program does perform dark frame subtraction, and these are stacked using a rolling median estimator (no need to register these though). I normally take about 10 darks at the start (which I am visually observing), this is then used during the live viewing. The median estimator means you can add dark frames as and when you like, and I found with around 7-10+ exposures it gets to about 1-5% of the actual median value.

In terms of a tracking platform, you will need a set-up which can track sufficiently for the period of time of a single sub. I have been using 30 seconds as it seems a good compromise between the 'live' experience, sufficient time to gather a meaningful signal, and also running the mount in alt-az mode without too many issues. If using smaller exposure lengths then the stacking will help bring more of the object out. The stacking algorithm that will be going into the app will auto reject duff frames - I get about 1 in 10 frames that should be rejected due to excessive alt-az movement.

I am currently implementing colour decoding for the Lodestar-C - once this is complete I will begin adding the stacking algorithm. If you would like a copy of the app then ping me an IM with your email address and I will send you over the latest version (if you don't mind beta testing of course..  :grin: )

Will ping.

Actually, I'm a daily Matlab user myself (speech/hearing signal processing) and have been exploring (i.e. mashing up some code) for registration/stacking of untracked widefield DSLR images with a view to eventually enhancing the live experience via short subs. Hope I can find some way to contribute, certainly by beta testing  :grin:

Cheers

Martin

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