How do you keep objects in view under high magnification? I have an EQ mount for my reflector and at 300x I can't so much as touch my tripod or breath. If it were not for the worm gears and ra gear I would not be able to keep anything in the eye piece.

But dobsons use alt/az mounts and have to be adjusted by hand. In practice how well does that work?  All that aperature would go to waste without the ability to point it at the object you want and keep it in the eye piece right?

Or do people use dobsons at low mag to look at large objects like Andromeda?

I'm also open to recommendations for finding a good dobson.  

I have a 10" Orion XT Classic and routinely use it at magnifications of 240X and have tracked with it as high as 480X.  The ability to track at high magnification with a dob is a function of the 'sticktion' of the bearing surfaces.  The altitude bearings on my XT10 are the stock teflon pads installed at the factory, I have replaced the azmuth bearing teflon with 1" Magic Sliders from the local Lowes.  While I would not claim that my scope's motion is "buttery smooth", I have no complaints.  I also think that technique makes a big difference.  I know that I am more adept at moving the scope smoothly now than I was in the first few weeks after I started using it.

As far as recomending a scope, I think all of the major players make a good product. I like my Orion very much and would probably stick with that brand in the future if I were going to upgrade to a 12", but I've also heard great things about the Zhumell line of dobs, and the Mead Lightbridge scopes.

Howdy Kodack!

The simple answer to your high magnification question is... with great difficulty!    High magnification is generally used for planets and the lunar surface where you can tease out additional detail.  Objects such as the Andromeda Galaxy are better suited to lower or medium magnification... and a clear moonless night.

Aperture is never truly wasted but I understand your point.  The more light you can gather (on a good mirror), the better the views will be and you'll be better equipped to pick out fainter objects.  You are quite correct!  Keeping an object centered in view at higher magnification will keep you very busy with the RA and Dec slow motion controls.  This really detracts from the viewing experience and be very frustrating.  It's tough to focus your attention on the object when you're tweaking the control knobs and the object is whizzing around in the eyepiece... or moving completely out of view.

Here are a few suggestions... in increasing order of cost.

Since you have an EQ mount, you might want to look at buying a drive motor for the right ascension axis.  A drive motor on the RA axis will stop the object you are viewing dead in its tracks... even at higher magnification.  You'll probably still need to make some declination axis adjustments on the fly, unless you've done a superb job of polar aligning the mount.  Even a single axis drive motor will do an infinitely better job than attempting to make adjustments by hand.  Single axis systems are quite inexpensive.

The next step up from the single axis (RA) drive motor would be a dual axis drive motor system.  Dual axis systems come with a drive motor for each axis and a hand control which will allow you to make both RA and DEC adjustments electronically... in much finer increments than you could possibly make by hand.

The ultimate system for your EQ mount would be an add-on GOTO system.  Systems like this will not only do the tracking for you, they will find celestial objects for you as well.  These systems can get expensive and are not adaptable to all EQ mounts.

Please note that not every EQ mount will accept the equipment mentioned above.  If you could post the type of EQ mount you have, perhaps the group could make suggestions for appropriate drives for your mount.  We'd all be happy to help.

You are also correct about Dobsonian style mounts, and the necessity to move them by hand.  This is a trade-off however.  The beauty of these systems is that they are typically much lower in cost per inch of aperture.  Large aperture with lower cost makes all amateur astronomers smile!  Yes, Dobsonians are alt/az but there are solutions to the higher magnification tracking issues.  Equatorial platforms are available which will do the job nicely.  Again, it is necessary to do a reasonable job of polar aligning the platform in order to get maximum tracking performance.  Here's a web link (selected at random) to give you additional information about equatorial platforms.  http://www.equatorialplatforms.com/  There are a number of manufacturers out there, but this will at least get you started.

If you want to "run with the big dogs", and have a fairly healthy budget, you can outfit a Dobsonian mount with a complete tracking and GOTO system.  These system remove nearly all limitations associated with alt/az mount arrangements.  Again, these are a fairly costly solution but they work very, very well.  Here are two "tried and true" systems, for your review.  http://www.tech2000astronomy.com/dobdriver/  and http://www.stellarcat.com/.

Hope this helps!

 Kodack - I use a 10" f 4.5 newt on a EQ mount and when observing at medium to high power, I locate the object, then move a couple of f.o.v.s in front of its path and let the object drift by. Doing this allows the scope to settle down and provide stable (no jitters)  views of the object as it passes by your f.o.v. True, it's a cheap, dirty trick but it does work with a little practice and patience and allows your eye to dark adapt a few seconds before the faint object  appears in the dark f.o.v. (with no bright stars in it).

  Hope this info helps you, no mater what scope type you decide on. Mr Q
 

Just my opinion of course,

I love observing with my GEM mounted 8" Newt or 6" SCT.  I will never own a Dobsonian mounted scope simply because of my laziness.  Sure it would be awesome to look through a 12" or larger scope more than once in awhile but when I am on my lonesome I just don't want to haul around a monster that I have to fiddle with.  Once I get an object in view I want it to stay there where I can relax and enjoy the view without having to do anything.  No worries about magnification or changing oculars.  If nature requires a response Saturn will still be in the eyepiece at 300x when I return.  Plus I can sit down the entire time I am looking as well.  No ladders or akward tiptoe positions where I might fall into the tube! 

Aperature fever is real.  But with it comes longer cool down times, weight, bulk, careful collimation, and stubbed toes.  It all comes down to what you feel most comfortable with and what you will use most often!  In my personal opinion I have the best sized telescopes for what I enjoy doing most of the time. 

But that is just the opinion of one older guy in love with comfortable viewing under the stars.

Enjoy your search!

L

 The scope I have now is a 130mm celestron with the EQ3 mount. Somebody had mentioned moving RA ahead and then letting the object drift across the eyepiece, this is the only way I can view saturn at max mag and because of the low viewing angle on my 4mm I also have to view with both eyes open so that the planet appears to float in front of my face, this actually works pretty well. I've regularly viewed Saturn with 4mm and a barlow for 325x.

 
However even with 5" of aperature when I point at something like the Orion nebula there is very little nebulosity and little color. I'm not expecting a 10" dob to give me stacked image type clarity but it would be nice to see a hint of color when I'm looking at something.

 
I'm also past the "oh what a pretty planet" stage and moving on into the "I'm going to find that blasted M** if it takes me all night" stage so I'm looking for aperture. I think it will also help when viewing with filters since even the best filter is still going to decrease the brightness of objects.

 If I get a dob I'd be using whatever mount it comes with and I think I'd take aperture over a goto simply because I don't want a computer to do the work. I get a sense of satisfaction out of knowing a particular patch of sky by sight.

 
On the other hand an SCT is pretty tempting for the ability to kick back in a comfortable chair instead of playing twister with the eye piece.


 

Kodack:

I'm not expecting a 10" dob to give me stacked image type clarity but it would be nice to see a hint of color when I'm looking at something.

Unless you plan on acquiring a 20" or larger aperture, don't even think about color. Even a 20" is probably too small. I have typically seen 25" noted as a minimum needed to experience faint pastel on the brightest nebulas, under the darkest skies.

If you want color, and don't want to go for the really big scope, get into long exposure photography.

Robert

On a dark stable night I have seen hints of a very pale green in the Orion nebula, and a hint of pale blue in the ring nebula. Other than that the only other objects I have seen any color in are the planets and stars.
OIII and UHC filters help enhance the views of most nebulae making the clouds of gas appear brighter against a darker background, however, they do not enhance any color. 

Learning to use averted vision and averted imagination are important when observing faint DSO's.

As for observing objects at high magnifications with a Dob, that comes with experience.  A good set of wide field parfocal eyepieces with the large eye lens helps also.

Keeping your bearing surfaces clean and dry is important in keeping the motion smooth. Replace the stock Teflon pads with magic sliders and keep them clean. Don't use WD-40, DuraLube, car wax or anything like that. Those things will only be the catalyst dirt and gunk need to adhere on the surfaces preventing smooth motion.  Plain old rubbing alcohol is all that is needed to keep them clean.  

Keeping the bearing surface clean and moving smooth helps when viewing objects at high magnifications. You will get to where you can follow along with the object without annoying vibrations. But when those bearing surface start getting dirty and the friction/stiction increase, then it gets harder to follow objects.

BTW, believe it or not, sometimes a little love tap on the side of the OTA when observing some objects will help tease out a little more detail.

Have A Nice _________

Some color can be seen in apertures much smaller than 25", although large apertures make it more readily apparent.  I've seen various pastel hues including blue, green, and pink in M42 through a 14.5" Starmaster Sky Tracker Dob on exceptional nights.  A number of bright planetary nebulae appear as blue or aquamarine through small apertures.  Planetaries such as NGC 7662, the Blue Snowball, exhibit color through my 101mm Tele Vue refractor.  IC 418 in Lepus is known as the Raspberry Nebula for good reason.   

Dave Mitsky

During its 1999 apparition, I tracked Mars at 455x (the highest magnification that I had available at the time) for a half an hour on one occasion with my 12.5" f/4.8 Starsplitter Dobsonian.  The seeing was excellent that morning and I had a great view of the Red Planet.

Dave Mitsky

tkerr:

Learning to use averted vision and averted imagination

The imagination would seem to be the most useful attribute in seeing colors with scopes less than 1/2 meter.

Robert

The comment Tim made earlier about widefield eyepeices is right on the money.  Tracking with my 10" Skyquest dob is much easier with the 68dg EP's I typically use.  I frequently see color in the brighter planetaries, and have seen hints of green in M42 on exceptional nights.

I know that one of the initial questions asked was related to solving the object drift issue at high magnification, but there is a lot to be said about rich field views.  It's not unusual to keep jacking up the magnification to see if any additional detail will pop out.  We've all done it... newbie and veteran alike. 

Over time, and as your experience at the eyepiece grows, you'll find that pushing your scope to the max really won't yield what you are looking for.  An amazing amount of object detail is available even at low to medium powers.  It just takes practice.  You'll find this especially true as you move toward the M and NGC class objects as you indicated.  Rich field viewing has a certain beauty unlike any other... in my opinion at least.  If your 130mm Newt is the f/5 variety, it is pretty much designed for this type of viewing. 

You might want to consider a longer focal length instrument, over time, if higher powered viewing is what you are ultimately after.  If you end up like most long-term amateur astronomers, you'll probably buy a few scopes (at least), each dedicated to the type of observing session you are planning.

 I do most of my viewing at very wide viewing angles with a 30mm plossil. Even at that size though the field of view is quite small when compared to my binoculars. I have a 12x60 Celestron bino kit that serves me well in that regard.

 If I had more aperature though I know that my views of the planets would be greatly improved, especially the dim twins beyond Saturn. I really only drop below 25mm when looking at the planets. I find the images are more appealing, even if less detailed, when they cover a larger area.

 
M42 would be spectacular in the 10" and up range as well I'm sure. I got a few months to decide before it starts hanging out in my part of the sky again. But I want to be ready for Jupiter when it hits opposition. I really want to see some detail this time.

The most I've got out of my 130mm is a fuzzy ball with no detail, banding, or color. (I haven't had a chance to revisit since fixing collimation)
 

 The
 

Generally Plössl eyepieces have a narrow apparent field of view of about 50° or 52°.  What you might want to consider are some eyepieces like the Baader Hyperions or Orion Stratus which have a 68° AFOV which are in a reasonable price range, and are very good eyepieces in their own class.  Then if you want to step up to wider AFOV eyepieces you will want to save your money. Then I would start looking at Nagler or even Pentax..

Getting a larger telescope such as a 10" or larger will give you the ability to increase your magnification well above the range a 5.1" would. Atmosphere permitting of course.. Not only will you be able to use higher magnifications, the increase in light grasp will also give you a very noticeable increase in resolving power.  At 250x or higher magnification in dark stable skies Jupiter and Saturn will blow you away..
As for seeing the outer planets, Well even in a 10" they are very small, something even hard to tell the difference between them or a small planetary nebula.. The only give away is the faint color blue or aqua green, depending which one,  you would see in either of them.

If you do get a 10" or larger Newtonian(Dob) there is a trick you can use to bring out more detail in the larger planets and moon with out a colored filter.  It is something you will have to invest a few dollars in and make for yourself.  It will have a psychedelic side effect, but that is easy to ignore if you choose. Kind of cool if you ask me though..  It's called an apodizing mask, and if you do a search here in the forums you will find a few threads discussing them and one or two that I posted links for instruction on how to make one. If you can't find it let me know and I'll get it for you.

BTW, you should remove the extra a
Someone was bound to say something..
 

Have A Nice __________

 Yes I read about those when I first joined the site. They seem to operate like a kind of make shift polarizing filter am I right? At least that's what I suspect from their construction.

So there are eyepieces other than Plossl? That I did not know, I assumed it was just a fancy name for "eyepiece" :)  Can you explain the difference in construction? I'm assuming they would have a more spherical lens like a fisheye, does that cause vignetting?

There are many different designs for eyepieces just as there are different manufactures that make them and or have their own patent designs.

Read the following to learn more.

http://www.hypermaths.org/quadibloc/science/opt04.htm

Have A Nice __________

Another source of info concerning eyepieces

http://www.televue.com/engine/page.asp?ID=131

a useful online calculator:

http://www.televue.com/engine/page.asp?ID=107

and info concerning their high end eyepieces:

http://www.televue.com/engine/page.asp?ID=144

Robert