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My quest for better DSO views/filters or video astronomy??


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From my quite badly polluted skys i have always been quite underwhelmed with the views of DSOs i can get through my 250px M13 i believe is one of the more impressive DSOs and that is still really very dim from where i live - the double cluster looks really nice though. honestly i exspected a little more, and traveling to darker sites is a rare thing for me.

The only nebulas i have seen have been the great orion nebula and the ring nebula , and the ring was very faint. I know there called faint fussies for a good reason now! lol:)

So in my quest for improved DSO viewing from home what route do you think i should go down? buy some filters like OIII , or save a bit more and give video astronomy a go??.

What improvment is video astronomy compared to visual?. pros and cons?.

Edited by Madhatter
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theres nothing like seeing things with your own eyes...if you wanna see stars on a pc...use google

a 2inch OIII gave fantastic views in a 400p... a 1.25 inch in a 200p was not so impressive...they may have been different makes tho...both were borrowed

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This post is so relevant to this group. Most beginners are so disappointed when their expectations of what they thought they should be seeing does not come close to what they actually see. And more great telescopes are sold within a year for this exact reason. The way I see it is you've got two choices. Accept that you overestimated what you might see in the first place and be happy that he faint fuzzies is as good as it gets for many DSO. Or get into astrphotography and then you get the best of both worlds. ie locating the objects in the first place. And having a much better visual proof of what you were looking at the previous night. I'd choose the latter.

Edited by sabana
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I'm still very much on the Beginners side of things and wanted to look at DSOs. With a 127 Mak they are very much Faint Fuzzies so I looked at astrophotography and what I could get out of that, as I do photography anyway.

I like the satisfaction of knowing that the images are mine, they are taken by me, through my equipment and processed by me. They may not be HST quality but they are mine.

First stop was a second hand EQ5 Pro Goto mount, that made seeing much better but the scope is really too slow at f15 and it would mean really long exposures with a DSLR (your normal SPC900 or Neximage webcam is no good for DSOs). So I managed to find a second hand 102mm wide field refractor which is much faster at f5.

Some reading was done with the aid of "Making Every Photon Count" and I did some test shots with a standard Canon EOS 400D, no filters, no guiding, just polar aligned the mount, focused as best I could, picked the object and started taking images.

This is what it produced, and I know I can improve on it:

71822d1319759386-first-real-doss-m31-m33-m31-27102011.jpg

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Realistic expectations is the key. Even with a big scope, faint grey fuzzies still look like slightly brighter faint grey fuzzies! Which is why, I guess, newcomers often get disillusioned, and in the modern fast-paced media world we expect instant dramatic results. Personally, I still get a huge kick out of seeing them visually, even if they are faint grey smudges. My kids think I am wierd.

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O-III and / or UHC filters improve the contrast of nebulae but don't improve the views of other DSO types, they can dim them in fact.

You have enough aperture to give great views but you really need to get the scope under dark skies so that it can show what it can do. I took my 6" mak-newtonian to the SGL star party earlier this year and was really impressed at what it could do on a wide range of DSO's - it performed like my 10" newtonian does at home so next year the 10" is going to the star party ;)

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There are three major things that improve the visual impact of DSOs in my experience.

1) dark skies, the darker the better and with no local lights if possible.

2) larger aperture - as large as you can transport and handle

3) a decent Oiii or UHC filter for some targets

If you can combine all three then your views will be better and better. If you can only get one then dark skies are the best and closely followed by aperture. With aperture you often want more even when you have a large scope, but the logisitics of transporting and moving a large scope, and of course the cost start to restrict what you can do.

As John said, if you have one scope and get it under dark skies, the views will be massively better than at a light polluted site.

Personally I also believe that a larger aperture also works better at home as despite many people's opinion to the contrary, a larger aperture will always be better than a small aperture for the average DSO (and especially for fainter DSOs, at least the ones that fit in the view) even in a light polluted area. The view through my 16" and 6" scopes on DSOs is not comparable even at home with the 16" winning every time. Larger apertures by ratio do not 'suck in' light pollution any more than small scopes.

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Dont get me wrong guys, i never exspected "hubble" like views or anything:) i just exspected a little more, but we love our scope and it will never be sold!.

I have never tryed stacking images but thats something i would like to learn now the webcams working.

i guess thats the main argument against video astronomy..if you want to do that why not use google, but its not quite the same, the views are live and where your pointing your scope, a group can be viewing the same thing, and coulors come into play.

i mean just look at this video through a 120mm refreactor, correct me if im wrong but even a massive dob wouldent even show this level of detail and coulor? ok this was filmed under very dark skys in australia...but you see what i mean.

i did manage to get my scope to dark skys once, and the views were vastly better:)

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I still get a kick out of finding dso's with my bins in my back garden. Small almost unrecognizable and shaky with my 15 x 70's. But a mile and a half drive to a very dark site with my 120mm refractor they are unbelievable in comparison. It's also important how you observe, I use the averted vision method and give my peepers a break every minute or 2 and I can tease out a bit more detail.

I read on here a while back that if you learn a bit about your nights targets from books and drawings it helps too. I've since bought and read some great books on messier objects and it really does help.

Mind you, all this said a 16" dob would be nice.

Al

Sent from my HTC Sensation Z710e

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I know what you mean, i do get a buzz when i find something:) and i think there is a few things i can do to improve seeing, the main one is give my eyes more time to get dark addapted and make sure the scope gets proper cooldown time, to often there is a small break in the clouds and i take the scope outside and use it strait away. It just hasent been clear enough recently to cool down the scope..clouds roll in way before it has had the chance:(

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Hi Madhatter

If your Dob does not have any tracking then video us going to be difficult as most of the preferred video cameras have some form of in camera integration (10 seconds for the SBC2000).

You cannot beat having the photons hit your own eyes, but video does help see a little deeper. The thrill is in locating the object and knowing that you have mastered the equipment just the same as visual observing but it's not for every one.

I'm happy with my video camera but would much rather have the views through Moonshanes 16" dob at a dark site anytime ;)

Clear skies

Paul

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Thanks DoctorD, il forget the video astronomy for now then:) and buy some filters.

On sunday this week and next i have the chance to travel to really dark skys so fingers crossed the weather is good!

Ok - now im wondering what video astronomy would be like through a 16" goto dobsonian:D

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  • 1 year later...

Hi all,

I have been using various filters with my 8" lx 200 for the last several months.  I've been pretty happy with the results.  I was especially impressed with the Meade broadband filter.  It has a very wide band pass but seemed to fit the nebulas (for the most part) that I was trying to see.  I am using an sbc4000.  I am seeing good views of Ring, dumbell, M13, Trifid, Lagoon, Swan , Eagle and Orion and dumbell.  The thing that surprises me is I'm seeing these in heavy sodium vapor polluted skies(Street light no more than 50' away. The filter does a good job on blocking the sodium pollution(In my opinion).  I just recently tried an O III (Lumicon) filter to compare against the broadband(Under same polluted situation).  My initial impression was ho hum.  I feel that maybe the Dumbell nebula acutally came out with quite a bit more detail than the other.  The Ring looked about the same.  I tried several nebulas that I haven't been able to see (Veil, Crescent, N. American etc.) Sorry to say, not successfully.  I am reserving judgement on the O III for futher

work at a darker site.  Right now the broadband filter is holding all the cards.

Dennis

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An interesting topic.......

I am in a similar position - with light polluted skies at home and only very rare visits to dark skies.

I eventually went down the GOTO route to find those objects which star hopping techniques had failed to find because of LP. Having found them I began to enjoy the astronomy experience much more but still many of the fainter objects eluded me and detail on those that I could find could be better.

I then discovered video astronomy and have just begun the journey - it is much too soon to say if it was the right choice as cloudy skies and the need to master site specific camera settings, capture and stacking software programmes etc. have not allowed me to experience the full potential of VA.

I am, though, enjoying the learning experience and am looking forward experimenting with VA over the coming months.

Like many others I don't think you can beat observing under dark skies with a telescope - but VA does seem to offer the opportunity to significantly enhance observing from poor quality sites.

There is a good section on VA in the "Science" section of the forums and much is currently being discussed regarding the Phil Dyer Colour video camera - which I have now purchased.

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