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The "No EQ" DSO Challenge!


JGM1971
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9 hours ago, happy-kat said:

Well captured.

Did you try any in colour to see if it was green?

Yes, of course, but the sensitivity of my color camera is very bad. I made a gif too from 20 monochrome  pictures, because of my alt-az mount its a little bit funny ?(the stars takes a round, but the comet is moving between them), but I want to entry with this gif into imaging challenge #17. The 20 frame was taken with my phone, and Celestron Nexstar 8 SE with 25mm plössl eyepiece, in every 10-12 minutes in the intervall 00:16-03:53 2018.08.16.  Do you think, is it a good idea? Or better to entry with a single shot? 

20180816_043311.gif

IMG_20180818_195451.jpg

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6 minutes ago, happy-kat said:

The moving gif is really good it shows the speed difference of the comet.

Really like it? :) It makes me happy!! I don't know, how can I get the angle, what I see in the eyepiece? This is 80x magnification with my 2000 mm focal lenght instrument, the diameter is 200 mm. 25 mm plössl eyepiece?

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On 18/08/2018 at 08:19, smisy said:

I tried again the comet 21P Giacobini-Zinner, Celestron Nexstar 8 SE, Alt-az mount, Huawei P10 smartphone, monochrome camera, 25mm plössl eyepiece. 2018. 08.15. 23:52, Hirschegg im Kleinwalsertal, Austria. 30 sec exposition at ISO 1600.

 

Well done!

I did also try on that target. As it is not exactly Deep Space but you give me good excuse to post it here too :)

 

C12P.gif

And the stacked image:

C21P.thumb.png.a77b5b6c4c413ca66182bd4d4af94b82.png

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17 hours ago, smisy said:

Very nice job, Calli! How did you stack the pictures? I think, over the sun and moon + planets everything is deep space object, or isn't?

The animation was Normalized/Calibrated and Registered (Preprocessing tab) in "regim" (as DSS did not work with my files). Then I used these .fits files to make ,tiffs and stabilized them in Blender (https://blender.org) a complete Open Source 3D Suite which can also do tracking and stabilizing of footage... Yes at least one App I know for sure ?

The stacked one I am not sure anymore, I think I use also regim and then used Fitswork batchprocessing to track on the Coment? I really forgot it was a bit a PITA...

Carsten

Edited by calli
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Hello,

here is the famous Trifid Nebula captured last week with my SkyVision 400mm (FD/4) at 1600mm without autoguiding and in altaz mode of course. Derotation with the Optec Pyxis LE Rotator.

Subs of 20s with Sony A7S modded (astrodon)

Clear skies

Michel

0D3D28C3-0063-44D2-847B-6EC89796AA71.jpeg

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  • 3 weeks later...

Hi Everyone,

First of all I will state the obvious, Fantastic Thread!.

I would very much appreciate some guideance, I have a Nexstar 6SE, wonderful little scope, and a Canon 450D camera.

I would very much like to try AP on the Great Orion Nebula, you guys have posted some wonderful images, absolutely amazing!

Now for me to image this nebula I take it that I should attach my camera to the scope with the prime focus method? Without a Barlow or anything?

My second question is, with this scope and the camera at prime focus, what would be the max exposure time that I could achieve before the stars star to trail?

Additionally if you have any suggestions as to what I could do with this very basic set up please let me know, such as what to image, use a EP or not etc.

 

Any suggestion and guidance would be very helpful.

 

Ian

 

N.B

Thus far I have only used my camera on a tripod for the Milkyway.

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58 minutes ago, iandownunder said:

Hi Everyone,

First of all I will state the obvious, Fantastic Thread!.

I would very much appreciate some guideance, I have a Nexstar 6SE, wonderful little scope, and a Canon 450D camera.

I would very much like to try AP on the Great Orion Nebula, you guys have posted some wonderful images, absolutely amazing!

Now for me to image this nebula I take it that I should attach my camera to the scope with the prime focus method? Without a Barlow or anything?

My second question is, with this scope and the camera at prime focus, what would be the max exposure time that I could achieve before the stars star to trail?

Additionally if you have any suggestions as to what I could do with this very basic set up please let me know, such as what to image, use a EP or not etc.

 

Any suggestion and guidance would be very helpful.

 

Ian

 

N.B

Thus far I have only used my camera on a tripod for the Milkyway.

Hi! Welcome here! I work with my alt-az mount always with 30 seconds or less. With this mount it depend also on the position of the sky object, how long exposure you can take. Anyway if you work with raw files and you process them in Deep sky stacker or in another program, than better if you use 10-15 sec exposition. If you want only one shot, than use 30 sec! But in this case the align must be very precise. 

Clear sky! 

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3 hours ago, iandownunder said:

Thank you.

Am I correct to assume that the closer the object I choose to image is to the South Celestrial Pole the longer it takes for star trails to show?

i.e  30 seconds at the SCP and less the further away you go?

There was a big help earlier, this post: 

 

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Welcome to SGL. You might think that but the celestial motion gets a bit more complicated when you try to image with an Alt-Az mount. With a perfectly aligned mount, you should not get what you might call conventional star trailing, because the telescope tracks the stars. In the real world though, mounts aren't perfect, and Alt-Az mounts by virtue of the way they move, you will get star trailing. This worsens the longer the focal length of the scope. Really, the only way to know what sort of exposures to use is to experiment, starting at 30s and less.

There is also another type of trailing caused by the apparent rotation of objects over time. Again, this is inherent in the way the Alt-Az mount moves. This field rotation is least towards the East and West, worst towards the South and North, and worsens with altitude, being worst at the zenith. If you look back in this thread there are discussions about this. This alone can limit exposures to between a few seconds and a minute or more, mount willing. In fact I posted about this recently.

What imagers normally do is take a number (more often, quite a number, in the hundreds!) of short exposure frames and overlay them on top of each other, or stack them, in software such as Deep Sky Stacker (free) in order to reduce the noise levels caused by the short exposures.

Good luck.

Ian

Edited by The Admiral
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Thanks for the comments, weather permitting tonight I will do as suggested and start at 30 seconds and work backwards, the Orion Nebula is unavailable at the moment ( too low and only comes up in early hours at the moment and the moon comes up as well ) but when it is up high and there is no moon I would like to take some test shots and see what happens, not sure if my set up will show anything other than a bright star but will see what happens.

Cheers for the Link, will read it now.

Thank you all,

 

Ian

Edited by iandownunder
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3 hours ago, iandownunder said:

Thanks for the comments, weather permitting tonight I will do as suggested and start at 30 seconds and work backwards, the Orion Nebula is unavailable at the moment ( too low and only comes up in early hours at the moment and the moon comes up as well ) but when it is up high and there is no moon I would like to take some test shots and see what happens, not sure if my set up will show anything other than a bright star but will see what happens.

Cheers for the Link, will read it now.

Thank you all,

 

Ian

To start this with the Orion nebula is the best way, because it's very bright. May you can use smaller ISO with 30 sec, for example 800-1000. That gives less noise and more contrast. Have a clear sky! 

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Just the basic 18 - 55 camera lens.

As you know the scope is F10 and I am not able to buy a focal reducer so I will just try the prime focus method and see how that turns out.

When I took photos of the Milky Way on a tripod I could only manage around 20 seconds before the stars trailed, so when I have a try at the Orion Nebula at prime focus I think I may need to limit the exposures to 10 seconds, but like you say trial and error.

 

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4 minutes ago, primordial atom said:

thanks both, yes lovely dark skies on the shores (or should I say bonny banks ?) of Loch Lomond, unfortunately I was eaten by midgies ?

I think I could put up with Scottish midges compared to the Staffordshire Mosquitos this year... or perhaps not!

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