Thinking of getting a Revelation 12" DOB as first scope but......

Calibos

The old man brought up the first few issues of Sky at Night magazine recently and it has kinda rekindled my interest in Astronomy somewhat of late. I've been browsing a lot of the Astronomy forums and sites linked to from here over the last few days reading up on some of the different types of Telescopes, mounts and browsing through the image galleries.

I read about the Revelation 12" Dobsonian for instance for about 500 sterling. (How much would a decent finderscope and set of eyepieces be for this BTW?). Anyway, I never realised you could get this kind of apeture for so little these days. I know dob mounts are useless for imaging but I'm not sure I'd ever get into that anyway and obviously a goto mount takes away half the fun of exploring the sky. ie Starjumping to find something or randomly scanning the sky,finding something and then referancing a sky atlas to find out what you are looking at.

Which brings me to my main point. Seeing as I wouldn't be imaging but merely observing, what could I expect to see in the 12" dob eyepiece say with average seeing for example. I've seen some amazing photographs from similar aperatures but obviously the images are long exposures and/or stacked(whatever that means) Now I came across a pic of Mars tonight by someguy but unfortunately he didn't have his equipment in his sig. It did involve exposure times and stacking afaik. It was basically an almost full white disc with the tiniest hint of slightly darker area's. ie a pretty much featureless white disc. Not a great pic but it was one of his first attemps at planetary imaging though. Thing is though that a guy called greenward?? from Raheny who has a fabulous picture of Saturn linked in this thread I think commented on this other guys pic of Mars. He said that that was almost exactly what he could see through his eyepiece the night before when viewing Mars. Searched the Raheny fella's poasts and it looks like he has a huge Schmidt Cassegrain 10/12"??? Really impressive setup! So if thats what he see's in his eyepiece then I can't but help feel a little underwhelmed! I know most if not all of the colour and finer detail of celestial objects only come out in properly exposed/stacked images and that when viewed through an eyepiece most things in the sky are more like black and white photo's but I guess I was expecting more?? ie not expecting the planets or galaxies etc to look half as good as the pics you usually see posted by these amatuer astrophotographers but for them to look better than a featureless white disc like mars looked in that pic. I mean my binoculars resolve mars into a white disc rather than a pinpoint star (albeit a very small white disc!!). I was hoping a large apeture telescope would resolve it into a bit more than just a larger white disc??

Of course this was only one example but are there any sites/galleries with pics showing 'This is exactly what mars/jupiter/staturn/Andromeda Galaxy etc will look like in the eyepiece at 200x on an 8/10/12" scope etc" to give me a better idea of what I could expect to see in the eyepiece?

Seanie M

Get It! Get It! Get It! Get It! Get It! Get It! Get It! Get It! Get It!

If I had the money, I would - but I have just bought a house so its a bit of a no-go till the bathroom gets tiled! :rolleyes:

I used one with a member from Kildare Astronomy Society, and its a fantastic piece of equiment. Well worth the money.

Seanie.

dbran

It seems to be extremely good value for the price advertised. 12" is quiet a huge amount of aperture for just €700. You can always get it mounted on a German equitorial mount and motorise it if you really want to.

As regards what you will be able to see it will depend on a number of factors. For a start forget about all those colourfull pictures that are posted up on the internet by the folks. These are after either a) long exposures or b) a series of shorter exposures added up together. Either way a lot of processing goes into it.

For deep sky objects you will never see other anything then a grey image as there is not enough light gathered by even the largest scope for the cones in your eyes to show you the real colour image. But because the 12' gathers so much more light you will be able to use more magnification on objects so what you will se more of is "detail".

But you will not always be able to use the highest mag on nights when the seeing is not so good.

Note that the rev 12" would seem to be quite a relatively large beast and you will need to be sure that you have sufficient space to store the thing out of the way. Remember sometimes the scope with the smaller aperture gets used the most cause it takes such an effort to get it out of the house and into the car etc.

Also as with any dob, it will not track the stars. This of course effects your astrophotography. But also you willl have to manually guide the scope otherwise the immage will drift out of the field of view. When using low mag this is not such a chore as it happens relatively slowly but for high mag for plannets it will be a bit of a real pain.

Hope this helps

Kersh

I have one of these. I got it 4 months ago, and it is huge.....
The views through it are great, but like has been said, they are just elongated/circular grey smudges, except the planetary nebulas, which show great colour, relatively speaking. Saturn was brilliant, i havent got out to see Mars yet, but I will. it takes about 2 hours to cool sown, so ya gotta put it out early!!
I got mine from Greenwitch.com, delivery took 4 days.
If you want you can pm me and drop by to see it.
Im in Dublin.