Posts Made By: Lorne Johnson

I used a fairly standard spray on from 3m, which is a contact cement if one spays both surfaces and lets them dry for 60 seconds before connecting. It worked fine. I think that it was what Joe Nastasi advised me to use.

I had that True Track system mounted on a Super Polaris and it worked pretty well, but it' not a very high torque system. If the gears are meshed tight they can bind and keep the mount from moving at all. Obviously the clutches must be tight. The scope and mount should be balanced in both RA and Dec (which you have already reported doing, and it shouldn't require paranoia either). Finally, as Ed ting put it, the RA gearing must be set up looser for a motor drive than we like it for manually operated slow motion.

Hope one of these works!

That's a good list. I would add the Double Cluster between Perseus and Cassiopea, and M11 (The Wild Duck) around the head of the Eagle--they are about my two favorite open clusters. If you get out fairly early the Saggitarius Nebulae (Swan, and Lagoon) should be nice in good transparency.

I have the plain old 1.25 inch variable barlow. It seems to work quite as well as my friend's 2.5X Televue barlow, but more versatile. (He hates making those by the way--lots of machining.) I don't need a 2 inch Barlow, but I'm tempted just the same. I hope that you find out more, and post it.

I have a 5 inch Mak (Newt) as well. You might try for the Blinking Nebula, the Helix, or the Rosette. I assume that you have done the North American (really needs a 2 degree field) and the Veil. Then, have you seen the dust lane in M 84? I've seen it in my 5 inch with averted vision (but I saw it first in the 16).

Unfortunately, my experience has been, that while I love my Mak, a whole new deep sky opens up in an 8 inch (or larger) Dobsonian. Portability , of course, becomes an issue. I have a friend with a 16 inch truss scope, it shows a lot, but I wouldn't trade my beautifully figured 8 inch for it because mine is small enough to use, and big enough to see a whole lot.

Personally, I don't think that you would go too far wrong with either an 8" or 10". I wanted to build a 10" and then had really fine 8" crop up at a price that I couldn't refuse. Thus far I have been living happily ever after. I would pay more attention to the quality of the optics and the size and weight issues than anything else. There are a number of good choices, and strong opinions (mine are the only correct ones of course). I find that I can carry my 8" (38lbs) out of the study through the living room, out the door and across the street in one piece. It makes it almost a grab and go scope. When i first bough the scope it weighed 46 lbs, and I lightened it with a saber saw--that 8 lbs was a big difference in comfort. It's easier to carry out than my 5" Mak Newt on a GP mount (and slightly lighter as well). When I looked at the Discovery 10" PDHQ the weight was double. I think the Orion is somewhat lighter. In the end, it's what you are able to happily carry what distance and around what obstacles. Thus, having the garage well cleaned out or living on a third floor, is far more significant than the absolutes put forward by us blowhards.

I know globulars will look better in a 10 inch, and you should see noticeable differences in many DSO's, but nowhere near as much difference as a good dark sky will make, or even careful flocking and use of a dew shield, or really good optics vs so-so optics.

Planetary detail will most likely be limited by the atmosphere more than your telescope, especially in the 8 to 10 inch range. But what the upper limit is will be dependent on your atmosphere. Where I live in New England I have never had a night that really was improved above 220x. (280x was still good, but I could not honestly say that I could see more at 280 than at 220.) Those nights are few and far between around here. I often get more pleasing views (not more visual information) in my 5" than in my 8", but on a really good night apeture certainly rules. Observers in Florida and Arizona do much better than that on a regular basis.

You might enjoy reading some of the short articles on Newtonians on Bob Royces web site (rfroyce.com). He really likes 10" reflectors, and he writes clearly with a lot of common sense.

I sold mine on Arstromart about a week ago. It's a good eyepiece at f/6, and a wonderful value. In the end I chose the Siebert 36 mm Observatory (which is significantly more expensive, and very nice to use--never seen one come up used). It was obviously a personal choice, and one would not go too far wrong with either.

I have an f/5.7 dob and its easy to collimate. Bob Royce has a good article on collimating Newtonians and another on coma(at rfroyce.com); he describes Newtoians of f 5.5 and up as being a relaxed system.
There seems to be some agreement that it gets noticeably more finnicky below f/5.
I would not go futher without reading the royce articles.

Observing is a skill. And, it doesn't look like television or images from the Hubble (which is significantly larger than the Starmaster and above the earth's atmosphere, and usually involves pretty sophisticated image processing). So, you're quite right, it doesn't have the visual wow factor, and my wife would agree with wildly on this. My 7 year old daughter's commets on observing Mars 44 hours after it made its closest pass to Earth in 58,00 years was "no, i can't see anything on the surface. Oh, I can see the polar ice cap . . . It looks like a white speck. You know, if we don't know what that was . . . it would look pretty boring."

But, we did know what it was, and something of how far away it was (c. 38,000,000 miles), and it is this acumulated knowledge and experience that can make the experience fill me with wonder, and my daughter, but not my wife. My experience is that most people couldn't care less, and there is no great failing in that. As a historian, I would suggest that our culture demands overstimulation. And, in astronomy, most of the stimulation is in the immagination, not the retinal image. As one becomes a more experienced and skilled observer (and I'm probably garden variety in both)the images get better, but its still the imagination that keeps me out at night--I mean that light from the Sombrero Galaxy is 65 million years old, and I can see it right now. Who said Jurasiac period?