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Could people please post pictures of what dso’s look like through a ST80 stacked and processed with clear nights?


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Here's an image of the Heart nebula shot with an ST80 and a Canon 700d about 5 years ago.  Processed in DSS and StarTools.

18 x 180 sec lights, 30 flats and 30 bias frames.

I acquired the ST 80 as a guide scope and wanted to see how it performed as an imager.   I haven't used it for imaging since.

Heart.jpg.da146aa4a056f4138d67b64487c48f47.jpg

Edited by almcl
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7 hours ago, Mostafa said:

Also, are the pictures in the simulation stacked and processed or not?

Again thanks,

That one aims to show images as they would appear through an eyepiece. They explain how the images are processed in the simulator.

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8 hours ago, Mostafa said:

Thank you very much!

But my goal is to use a DSLR instead of  eyepieces. I am trying to go for Astrophotography.

What mount do you have.... given that most DSO need stacked long exposures the mount is probably just as much, if not more important than the scope used.

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2 hours ago, malc-c said:

What mount do you have.... given that most DSO need stacked long exposures the mount is probably just as much, if not more important than the scope used.

The computerised GOTO mounts are too expensive, so I decided to improvise and an equatorial mount with just an RA motor drive.

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5 hours ago, almcl said:

Here's an image of the Heart nebula shot with an ST80 and a Canon 700d about 5 years ago.  Processed in DSS and StarTools.

18 x 180 sec lights, 30 flats and 30 bias frames.

I acquired the ST 80 as a guide scope and wanted to see how it performed as an imager.   I haven't used it for imaging since.

Heart.jpg.da146aa4a056f4138d67b64487c48f47.jpg

Thanks.

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You already have your mount and I gather have added a motor. You can start imaging with your camera and a camera lens as many deep sky objects are huge and there is a lot to learn anyway.

Practice with what you have improve your polar alignment, don't fully extend the tripod legs, if using a dSLR I use a red dot finder mounted in the flash hot shoe for aiming. 

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Can you advise us what make and model the mount is as some will be better than others.  It's really difficult to advise when we have no idea on how capable the mount and motor drive is

But if the motor on the RA axis is designed to work with the mount you have then it should provide good enough tracking for wide angle shots with your camera and lens.  Provided you can polar align the mount well there would be little to no tracking errors in a wide field image.  It's only when you start using long focal length lenses or telescopes that the alignment becomes critical, and limits the exposure duration before guiding is needed in order to prevent star tailing.

 

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5 hours ago, malc-c said:

Can you advise us what make and model the mount is as some will be better than others.  It's really difficult to advise when we have no idea on how capable the mount and motor drive is

But if the motor on the RA axis is designed to work with the mount you have then it should provide good enough tracking for wide angle shots with your camera and lens.  Provided you can polar align the mount well there would be little to no tracking errors in a wide field image.  It's only when you start using long focal length lenses or telescopes that the alignment becomes critical, and limits the exposure duration before guiding is needed in order to prevent star tailing.

 

It is a Saxon eq1 mount with tripod and Saxon eq1 ra motor drive, made for each other.

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5 hours ago, Mostafa said:

It is a Saxon eq1 mount with tripod and Saxon eq1 ra motor drive, made for each other.

OK it's obvious that you are trying to get into astro-photograpy on a budget.  But IMO the mount is not going to give you the accuracy and stability to do so. The drive is intended to maintain position for visual observing where it won't matter if the polar alignment is off, or if the battery is running low and the tracking is slightly slower.  The drive is a simple DC motor system and the mount will have a fair bit of backlash and lacs the precision required to produce sharp detailed long exposures.  It will be fine for taking pictures of the moon, or wide field constellations where single 20-30 second exposures with a 55mm lense will not show any error, but for any deep sky work that requires a scope or heavy lens and long exposures the mount simply is not up to it.

The mount is the most critical part of any true imaging rig, which is why you see pictures of HEQ5 / EQ6 / EQ8 with relatively small scopes on them.  Its their ability to precisely track even whilst carrying a lot of weight that they are used. And as anyone who ventures into imaging it is not the cheapest side of the hobby compared to visual observing.

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On 16/07/2020 at 16:44, almcl said:

Here's an image of the Heart nebula shot with an ST80 and a Canon 700d about 5 years ago.  Processed in DSS and StarTools.

18 x 180 sec lights, 30 flats and 30 bias frames.

I acquired the ST 80 as a guide scope and wanted to see how it performed as an imager.   I haven't used it for imaging since.

Heart.jpg.da146aa4a056f4138d67b64487c48f47.jpg

Why are the edges warped? And the stars an unnatural colour? Is this from the telescopes or processing?

 

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The image shows up the optical imperfections of the ST80.  It suffers chromatic aberration (coloured fringes around stars) and also coma. The focuser sags when a heavy camera is attached which makes the problems worse.

I never used it for visual as it came (secondhand) without a diagonal and without one the viewing angle would have been very awkward.     

The colours are approximately correct although the yellows are missing as a consequence of having to imge through a light pollution feature. 

Edited by almcl
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