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What am I missing?


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I'm v new to star gazing. I got a cheap Celestron travel scope several years ago for viewing the Jupiter, Saturn and Venus conjunction around Christmas here in the UK and a pair of binoculars last year but I finally bit and got a sky watcher 72 ED 72mm aperture 420mm fl) this year on an eq3 pro mount. I'm happy with the photos I'm taking now with a mirrorless Canon. See attached, 180 second exposures x45 stacked of the Iris nebula very roughly processed and a single 90 second exposure of M5 globular cluster.

 

However, straight after aligning on M5 and taking the attached photo I swapped for a 20 mm eyepiece from the old Celestron and refocused using some stars in view and I could only see a blurry distortion in the middle where M5 was, I tried the 10mm from the same kit and same result. If I thought this was what astronomy was like I would definitely forget about it. I can't overstate how disappointing the view was. But I'm completely satisfied with the photos which is my primary aim.

 

So do I try a better eyepiece or something?

Iris.jpg

M_5.jpg

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If you could gather all the photons together that the 90 second image contains then you would see a difference for sure but our eyes cannot/don't do that. It's one of the reasons I stopped "looking" as my low light vision is rubbish 🙂 🙂

 

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I suspect my vision is going to be a problem if I rely on it much. To be fair I didn't let my eyes adjust to the dark before looking. I was using a computer screen a few seconds before so perhaps some time in darkness and patience would do!

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Much depends on the object you're looking at. Are you saying that M5 was a blurry distortion, or everything you look at?

The 72ED is a very nice scope but for examining faint fuzzy targets it's perhaps not the most impressive performer due to its limited aperture. Observing from a dark sky site will make a big difference, but a larger aperture may be the best way forward for visual deep sky.

Edited by mikeDnight
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M5 will look like a faint fuzzy blob in a 72mm scope.   An image with a 90 second exposure will look much brighter and more impressive.  That's why imaging is so popular.

M5 looks more impressive in an 8" telescope, a size commonly used by visual observers these days.

Edited by Cosmic Geoff
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  • 5 weeks later...

 I can't overstate how disappointing the view was. 

That sentence there what you wrote is the main reason I switched from visual astronomy to astrophotography. I was using a skywatcher scope at the time 8" apparture, 1200mm focal length. Even with this scope, nebula, galaxies etc are nothing more that fuzzy blobs. Unfortunately that is really all you will see with a naked eye. Although sky quality, less light pollution, better optics, larger apparture etc. all will help to tease out some detail but nothing like what your photos show. That's just how our eyes work I'm afraid.

What I started to understand is that although the view might not be that impressive, spare a thought to how long those photons have been traveling before they get to your eye piece. Try using a manual scope to try and find as many galaxies, faint fuzzies etc, by using star charts and star hopping. That way it's more of a challenge. Or just give up on visual astronomy and stick to astrophotography. That's what I did and find it alot more enjoyable now.

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With a few notable exceptions, many targets we observe are faint, indistinct, subtle etc. While I have and will always stick with visual observing, I can quite understand why many turn to imaging or electronically enhanced observing to pursue their interests in astronomy.

Fortunately we have great forums such as SGL which cater for the myriad ways that people like to "do" astronomy 🙂

 

Edited by John
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