Novosibirsk TAL 200K Klevtzov Cassegrain


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Novosibirsk TAL 200K Klevtzov Cassegrain
Excellent scope for the money. Built like a rock, has withstood a couple of drops. Good eyepieces with it. Pedestal mount a bit low, but still rigid as a rock

Overall Rating: 9
Optics:9 Mount:9 Ease of Use:9 Value:10
Weight: 1 (Unreliable Vote)
Date:
By: Anonymous (xxx.xxx.81.219)
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=70455


Novosibirsk TAL 200K Klevtzov Cassegrain
I had two of them: the first one went back to the shop for aligment (collimation) which turned out to be impossible. So I got a replacement (newer) 200K and I 'm very pleased with the optical performance

Overall Rating: 9
Optics:9 Mount:8 Ease of Use:9 Value:10
Weight: 1 (Unreliable Vote)
Date:
By: Anonymous (xxx.xxx.184.153)
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=89229


Novosibirsk TAL 200K Klevtzov Cassegrain
Optics is quite good, maybe not superb, but realy good.
But mount.... well its not a mount, its a poor joke :(

Overall Rating: 7
Optics:8 Mount:2 Ease of Use:8 Value:8
Weight: 1 (Unreliable Vote)
Date:
By: Anonymous (xxx.xxx.189.194)
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=338781


Novosibirsk TAL 200K Klevtzov Cassegrain
The (cheap) focusser should be better. Only 1,25 inch oculairs can be used. The Tal Gem mount is to light. Better use a H-eq5 or a eq6.
Sorry, but the optics are mutch, mutch better than a Celestron C8 or a Meade LX90/LX200. Why a 9? Only a Tak Apo earns a 10.

Bert

Overall Rating: 8
Optics:9 Mount:6 Ease of Use:8 Value:10
Weight: 1 (Unreliable Vote)
Date:
By: Anonymous (xxx.xxx.148.64)
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=426308


Novosibirsk TAL 200K Klevtzov Cassegrain
I purchased this scope because of its peculiar optical design (klevtsov cassegrain), its affordable price, its "small" size, its excellent 8x50 finder and its often excellent reviews. Another reason is that this scope is accompanied with a set of accessories which mean you can start observing right after unpacking the scope!

I was a little bit surprized about the size of the baltic birch wooden case in which the scope is packed :)

After 2 weeks of use, I must say I am very happy with the optical performance of this scope. I get pinpoint star images! Unless others I have a rack and pinion focuser with no play at all. However I envisage replacing it with a motorized focuser some day, allowing me to focus without vibration problems (I observe most of the time on a concrete patio). The finder is easily adjusted (hint: also set your crosshair in RA and DEC) and has an excellent optical quality.

This scope came with the new TAL GEM3 mount (with illuminated polar finder) on a steel pier. The mount has a 12VDC stepper motor instead of a 12VAC clock drive motor (as in the GEM2). It correctly tracks the objects, most of the drift is due to polar misalignment. Polar alignment is fairly accurate. There's a reference screw on the pier, which you should roughly point north (northern hemisphere assumed here). The mount head provides 2 bolts which can be used to finely adjust the north direction (unlock in one direction and lock in the other direction). Polar height is adjusted with a worm and wormwheel which is operated by hand (my mount has a little play here; I'll remove that play with a set of washers).

There's one peculiar thing with the DEC axis: it is much more sturdy to move, and the reason is that it uses slide bushings instead of bearings. The very positive advantage is that there's absolutely no play in Declination. Slew rates in RA are very slow (about 0.25x to 0.5x I guess), and the stepper motor only rotates in one direction. This is explained by the single-axis drive. One important fact on the GEM3 mount: you MUST NOT rotate the RA knobs while the RA motor is running. If you know this, then there's no problem at all. Otherwise you may damage the mount (I was told this in the shop where I bought mine).

Regarding vibrations, I observe on an "unforgiving" concrete patio, so vibrations can't easily move to the ground. The counterweight shaft is 14" long (40cm) and about .75" (18.5mm) in diameter. I think vibrations can be reduced by adding an extra counterweight and moving the entire counterweight "mass" closer to the mount head. If I don't touch the scope, I don't get any vibrations.

The scope is easy to use, but the telescope parts are rather heavy. This is not a scope you'd give to a 12yo kid, unless it's permanently mounted or an adult is always present when setting up and packing the scope. It takes a little practicing to deal with the DEC axis stiffness. The scope cools down very quickly (15-30 minutes). Sometimes I have to search for the RA and DEC lock levers, but that's a matter of exercising :)

I must say I am delighted with this scope. Maybe one day I'll buy another mount for this scope, but that will only happen if I envisage photography and CCD. Otherwise this scope (and the mount) is really worth the money!

Best regards,

Olivier

Overall Rating: 8
Optics:9 Mount:7 Ease of Use:7 Value:9
Weight: 1 (Unreliable Vote)
Date:
By: Anonymous (xxx.xxx.79.134)
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=439584


Novosibirsk TAL 200K Klevtzov Cassegrain
Very well priced ota in the UK. In fact it is UKĀ£250 cheaper than a celestron 8" sct. I got mine 2nd hand.
Really, really, solid built scope, in a military weapon style birchwood case. Huge !! Has the magnificent Tal 8x50 finder. Uses 1.25" eyepieces only, and comes with an adjustable mirror diagonal. The r&p focuser does the job.
The optics on mine are spot on and this shows in the sharp views. Have had great views of the moon, saturn and various deep sky stuff. M57 was especially glorious.
I'll not be selling this any time soon.
A note to those worried about collimation issues. If your 200K is alligned, it wont be going anywhere soon. But if yours is off, http://www.telescopes-astronomy.com.au/
in Australia has a tool which will get it back in collimation.

Andy.

Overall Rating: 9
Optics:9 Ease of Use:9 Value:10
Weight: 1 (Unreliable Vote)
Date:
By: Anonymous (xxx.xxx.239.40)
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=577562


Novosibirsk TAL 200K Klevtzov Cassegrain
excellent

Overall Rating: 10
Optics:10 Mount:10 Ease of Use:10 Value:5
Weight: 1 (Unreliable Vote)
Date:
By: Anonymous (xxx.xxx.110.187)
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=577606


Novosibirsk TAL 200K Klevtzov Cassegrain
I got this recent version a couple of years ago, which has the curved spider vanes and is an f/8.5 rather than f/10. I have had several C8s over the years to compare this to and it clearly bests them all. First off the build quality is substantial, it really feels hand-assembled. It certainly weighs more than a C8, I believe it's around 20lbs at least, but is shorter than a C8 by a couple of inches. Cool-down takes a good hour, even with the Sitall primary(I don't know why they don't advertise this feature!). Once acclimated the optics truly shine. Like Intes and Lomo units I have used, this also has the same smoothness Russian optics are known for. The faster f/8.5 optics do yield noticeably brighter images. Unlike the C8 and maksutovs, there is NO lateral color whatsoever, all the way to the very flat and sharp edge of the viewing field. I refer to that phenomenon, such as when viewing Jupiter, where one side of the planet has a reddish cast and the other side is bluish....utterly absent in this scope. The straight through finder is superb and the quick-release holder is very snug and firm. The stock focuser deserves mention. It is a single-speed, 1-1/4" unit, non-rotatable, but is very solid and smooth. Like the US-made Meade ED-Apos from a while back with their 2.7" rack and pinion focusers, this is like that where I do not feel the need to immediately upgrade. And it is not easy anyway. I got a Crawmach ultra-low profile unit custom made for this scope as a supplement, not a replacement, to use for bino-viewing using a Siebert 1x magnification OCA that only installs on a 2" diagonal to get the lowest mag. possible. Feathertouch and Moonlite could not make a focuser to replace the stock unit, just too short....only Crawmach had something available when they were around. Clement makes one that can do it.
But back to the optics. For most of the time I just leave the stock focuser on...it is fairly quick work to switch to the Crawmach when I need...just four screws.
The curved spider setup really works nicely to reduce spikes to a bare minimum....you really only see something in examining their shadow in the inside/outside focus diffraction rings. Planetary viewing is splendid at 1700mm focal length, baffling is great in cutting out flares from off-center bright objects, and resolution is pinpoint...Jupiters moons are discreet disks of varying size and color, and with 32.5% central obstruction( I leave the plastic slip cover off the secondary holder, which hides the adjustment screws- NEVER to be touched by the way!), contrast is still very high for discerning subtle banding.
Collimation is done via six bolts arrayed around the focuser under a snap-on rubber ring that can be removed, and holds very well. I've only touched it up once and is not that difficult...if you've adjusted a maksutov through the real cell it is very similar.
The stock 1-1/4" diagonal this comes with is a very solid unit, and is collimateble! While a mirror diagonal, it actually has about the same in-focus distance as my 1-1/4" Tak prism diagonal....not sure how this is. The 25mm and 10mm plossls included are excellent EPs that compare very well to orthos and even Televue plossls I have had....a quality kit all the way around! Mine came without a mount, but arrived safely encased in a wood crate, and neatly protected in fitted styrofoam in it box.
This puts up the cleanest and most vivid set of diffraction rings I've seen from any scope, including Intes-Alter and Lomo units, simply textbook and sharp, crisply defined. I have no issues with the open-tube design as it does reduce cool-down time...I use no dew-strips or flexible dewshields.

Overall Rating: 9
Optics:10 Ease of Use:8 Value:10
Weight: 5 (Veritable Vote)
Date:
By: Merrel321
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=608515

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