Posts Made By: Owen Chin

Hi Bob,

Perhaps. I'm in the minority but I have a Tak Mewlon 210 which I bought to complement my TMB 100/800. I use it together on my dual head Giro GR-2dx or alone on my Losmandy GM-8 with no problem. It is an open tube design so it cools down faster than the MCT or SCTs and the OTA, inch for inch is lighter than the two as it weighs in at 17lbs. It has killer contrasty views for DSOs and also for lunar and planetary. Despite the rumours, I find that it holds collimation well. On Astromart they go anywhere from $2000-2400. The Mewlon 180 with a inch less aperture goes from $1350-1700 and is several pounds lighter.
Using a Nagler 31mm my Mewlon at 80x is great for DSOs and a Nagler 12mm or 9mm are great for lunar/planetary and obviously you get the quality of a Takahashi.

I hope this helps, Owen

Michael,
When I went shopping for a 4" APO, I narrowed it down to the Tak FS102 TV 102 and the CNC TMB. Sight unseen, I poured over Ed Ting's, Excelesis, Cloudy Nights reviews and archived over the Tak and TMB Yahoo groups. I imagine you have done the same so I will defer to them for a detailed analysis. At the time, outfitted, the Tak came close in price to the TMB which included rings, finder bracket and case. I was drawn to the uncompromised build and design of the TMB, that it was a triplet over a doublet, and could work with a binoviewer sans a barlow/corrector. I decided to take the plunge for the TMB but wasn't sure if I wanted a 100/800 over the 105. Thomas Back emailed me that for lunar/planetary the 100 will have the edge over the 105, which will have slightly more light grasp and a widerfield for DSOs. I choose the 100 and after comparing it against a 105, I would do it again (repost if you are interested why). S&T, and many have criticised the weight of the CNC tube, (outfitted in a 2" format with Naglers it pushes 20lbs or so) but for viewing it works great on my GM-8 and Giro GR-2DX. The weight doesn't bother me, in the case, it is compact and the views, as far as a 4" APO goes. are to die for. Have since compared to a TV102..no regrets. Have yet looked thru a Tak102, but I probably wouldn't change my mind. BTW, I do own a Tak and they are great scopes, I just think the TMB was the right choice for me. You may be leaning toward the lighter Vixen tube but the used prices on the CNC OTA since the S&T article regarding the weight, I think, have fallen to an artifically low price for what you get. (much of the added weight is in the massive 3" rotating focuser and finder bracket.)
Cognitive dissonance in the amateur astronomy equipment acquistion decision making process isn't a job..., it's an affliction.
Good Luck, Owen

Michael,

Weight and size IS a major concern for many. Robert's post is right on point. Much of the weight on the CNC is in the rotating focuser, then the finder/bracket, then the rings. The massive focuser was designed for photo/imaging weight payloads so it's overbuilt I've been told.(personally like like the heft and aesthetics of it) On the other hand, the lighter tube's focuser doesn't rotate but you get the Feathertouch which is a plus. (You can retrofit one on the CNC though). Rotating focusers are great on GEMs as the finder rotates as well, but for Altaz mounts, it is a moot point. (I forgo the finder and use a lighter dot finder instead anyway) The CMC mounting options require a beefier set up, so be advised. For a detailed analysis, I suggest you sign up on the TMB Yahoo group (access the archive or post the question) or you can email Thomas Back or Markus Ludes and ask them directly. The last I heard was that they were going to phase out the 100/800 for the 105/650 in the lighter tubes. It's purely a personal preference, so really think it out.

Personally I like the CNC. I rarely use my TMB on my GM-8, opting for the Giro GR-2DX which I dual mount with my Mewlon 210 on the GM-8 adj tripod using Losmandy dovetail/saddleplates. They counterbalance each other perfectly and albeit heavy, once counterbalanced front to back, it is very smooth and dob-like. Not exactly grab and go but hey, it's fun to compare the different presentations of both scopes alone or with others. Look at John Ford's set up in his TMB 152/ Giro XXL Cloudy Nights Review, with help from John, my setup is the little brother.

Good Luck and Happy Holidays to all,
Owen

Clyde,

Your Upswing mount has two 1/4" threaded holes in it to attach the TV clamshell. You might have balance problems and focuser problems at zenith if you try to attach it to the block mount on your scope as it will be too far foward.
Personally I would go to a machine shop buy a scrap 1/4" thick 2x6" aluminum plate. Drill and tap a 1/4" threaded hole at the rear centered for yor OTA and two 1/4" slotted holes about an inch long and corresponding to the two holes on the Upswing cradle. This will allow you to balance your OTA by allowing you to slide it foward and back. (you can use masking tape on the underside of your plate do you won't scrape the Upswing cradle) Buy the necessary plastic knobs and 1/4" stainless hardware at Lowes and be done with it. It shouldn't cost you more than $10. Tube rings can get expensive and may not even fit inside the cradle and you may find that you need a balance plate anyway.

Regarding the tripod. Televue uses the Davis/Stanford Magnum XL tripod. You can buy one at B&H Photo with a 3way pan/tilt head for $100. If you anticipate aperture fever setting in later on, go for a heftier Bogen with a greater payload capacity and a locking center spreader.

As you can tell...I've been down this road before.

Owen

Don,

If I were to consider the liquidation of the equipment which you have to move up to a 5", I would not get a Meade.(I have a tendency to over analyze things...I guess that's why I'm in the hobby). Consider the highest price that you are willing to spend and go from there. I would look, from low to high, at the Vixen ED, Borg ED, Tak, TMB, and the AP. For the price of a Tak, TMB or AP, I would seriously consider spending the difference on a TEC 140 instead. But in any event, I think you will have to get a more substantial mount than your TV mount so will may have to factor that in as well (Unless you consider the Borg 125, which is pretty light).

By way of example, I have a TMB 100/800, looked thru an AP 130 F8.35 and got on the list for the 130 F6. But soon reality creeped in and I realized that I liked my TMB too much so I looked at other options. A Mewlon 210 came up for sale, so I surfed the learning curve and took the plunge. The Mewlon's light grasp on DSOs is superior to the 5" AP while the contrast is like a refractor. On nights of steady seeing lunar/planetary, if correctly collimated, is as good as I remember in the AP. And most important, the money I spent on the Mewlon would have been the same as if spent that and sold my TMB to come up for the difference needed for an AP 130..., but now I have both.

Good luck in you quest,
Owen

For visual lunar/planetary, of the three, I would opt for the TMB. Albeit a bit heavier due to the focuser, it rotates (a must on a GEM), the extention tube behind the focuser drops out to pick up the backfocus so it will take a binoviewer sans a corrector/barlow (a must for a two-eyed dedicated planetary/lunar viewer) and optically it can give an AP 130 f8.35 a run for the money (if you can find one). Although many may say that it is overbuilt...therein lies the beauty, everytime you open the case!

...but then again...that TEC 140 (which is not on the list) looks pretty darned nice too!

...but then again...that Tak Mewlon 250 which was for sale on the reflectors section (and about the same price range) on a steady night, would have walked away with everything...planets, lunar and deep sky!

Best Regards,
Owen

Hey Doug,

You know you can always skip the 9T6s and borrow my set of super light weight 9mmT1s for your finely tuned and highly balanced Dobs! It will be a match "swayed" under the heavens.

Owen

Rick,

A Starmaster 11"-14.5" ELT would be my choice, but I live in Florida. If you plan to view from the midwest, Mars will be pretty close to the horizon for a large aperture Dob unless you have some very steady nights. An APO in the 5-6" range would be my choice in your parts. (for planetary, there is a jump from 4-5") The TEC 140 would be my best bet. For a compound scope I would take the Tak 250 Mewlon. While many would disagree, I think it would give refractor-like images, have a faster cool-down than a MN or MCT, lighter and not subject to dewing up. Even though the TECs are killer, so I've been told, the weight and cool down is getting up there for my tastes. But on an APO or Mewlon or TEC, you run into the additional cost of a mount. Hence, I would go with the a SM ELT 11" or 12.5" with tracking if you can afford it and take a trip to the southern latitudes...you said money was no object!

Have Fun and Good Luck!
Owen

(FYI, I'm using a TMB 100/800 and a Mewlon 210 dual mounted on a Giro)

Mike,

For $3500 in New Mexico, I would go for a Starmaster ELT 11" or 12.5. They are very portable as Dobs go, give you much wider views than a SCT or APO, and the Zambuto optics will give you killer lunar/planetary images that will knock your socks off in addition to the awesome DSO views. The downside if if you want to image/photograph. But then again, to get a comprable APO in the 5-6" range, you would spend more and still have to purchase a mount.
As far as a SCT is concerned, I would rather have a Mewlon 210 or 250 or perhaps a TEC but, again you still have to spring for a mount as well.

Just my $.02
Owen

David,

Wide angle in a 1.25" format, you can't really go wrong with a 19mm Panoptic and on Astromart you can get one used in the $185-205 range shipped. In the 16mm range a Nagler 16T5 is really nice but will cost you and they rarely come up used on Astromart. If you need the eye relief look at the Pentax XLs as they afford a generous FOV as well.

Good Luck,
Owen