TS Optics 90/500 refractor - bargain?

[Alfian]

I came across this a couple of days ago:

http://www.teleskop-express.de/shop/product_info.php/info/p5616_TS-90-500mm-Rich-Field-Refractor-Telescope-with-2--Focuser.html

and although looks can be deceiving thought it looked very much like this:

http://www.opticstar.com/Run/Astronomy/Astro-Telescopes-Opticstar.asp?p=0_10_1_1_64

Probably from the same chinese production line.

Looking at the price -135 euros (about £115) I thought that this had to be a mistake - so I emailed TS Optics who I've found can always be relied upon to quickly respond - albeit in breif terms, asking if the price was correct. Email by return - yes it was - the price had recently been reduced, but they also pointed out that, as you would expect, the optical quality was that of a simple short tube achromat.

I interpret this as it is in the same mould as the SW Startravel ST80/102.  No diagonal or eyepieces  but even so - with postage that looks like a good deal to me. Good travel scope.

[emadmoussa]

Most definitely the same. A year or so ago I looked into these actually. Like you say it seems the TS one has been reduced in price.

[Naemeth]

Indeed they are probably the same, they do look like interesting scopes, slightly less CA than the ST102 though as it's F/5.5

[Dooshka]

Hello Stargazers

I have ordered one of these scopes, needing a lightweight RFT for my occasional travels, and it should arrive tomorrow. Assuming the wind and rain ever stop, I will let you know how I get on with it. From the photos on the TS site, the build quality looks better than SkyWatcher, more like a baby version of Kunming's 150mm achro which is variously branded. Might also think of it as a cheap 500mm telephoto lens and see how I get on with a bit of lunar imaging.

Dooshka

(Orion VX6XL, Celestron C11, Hyperion zoom, Meade 8.8 UWA and 32mm Plossl, ES 18mm UW, various Revelation eps)

[ronin]

Hope it arrives and you get a chance to try it, would be interested in your thoughts about it.

[Dooshka]

TS RFT905 First Impressions

The scope arrived on time, solidly packaged, wreathed in bubble wrap and safe inside a well-made soft carry-case with a strong double zip and sufficient additional space for the usual accessories. First impressions confirmed what I expected from the photos on TS's web-site. The build quality and finish are excellent. The action of the single speed 2-inch Crayford focuser is smooth and precise, and the graduated scale on the matt black draw tube is a nice feature. The retractable dew shield is snug to the scope but not too snug. It glides comfortably and I liked the fact that the lens cap is a screw fit to prevent it slipping off. Inside, the tube has a powder black finish and is well baffled to block stray light. No signs of grease or glue anywhere. First impressions are of a scope that is in a different league from the ST102, for example - not that I have anything particular against SkyWatcher - the ST102 was my very first scope which really drew me into astronomy. Any gripes? Well, just one. The tube ring grips the scope by means of a single small screw that I could only turn using pliers. Why not a hexagon nut? I had to adjust it because it was slightly mis-aligned and needed repositioning so that the scope would be balanced with the dew shield extended and a diagonal and eyepiece on the back. It's not an operation I would want to repeat too often and I shall be replacing the tube ring with a pair of SkyWatchet tube rings and a conventional dovetail as soon as possible. The supplied tube ring is threaded for attaching to a photo tripod and although this set up works, I would not recommended it unless you have a very sturdy tripod with a solid and well-engineered head. It's not that the scope is heavy (only about 4.5 lbs), rather it's the moment that's created by a tube attached at single point that makes this arrangement unstable - certainly on the photo tripod that I have. Until I replace the tube ring, I have attached it to the L adaptor that came with my Skymaster binoculars, and by that means mounted the scope very satisfactorily on an AZ4. First light hopefully tonight, if it stays clear and the wind eases sufficiently. I will let you know if the scope lives up to what it's build seems to promise.

[Dooshka]

TS RFT905 First Light

Q: What do you do with an RFT on a brilliant moonlit night? A: The best you can. Last night was the first time this year I have had any opportunity to spend appreciable time behind a telescope, mainly because of the appalling weather. To start with I homed in on the Orion Nebula using my trusty Baader Hyperion zoom. On this scope, it delivers 21x - 63x. As magnification increased, the Trapezium became even more distinct and the surrounding nebulosity clearer. As the Moon was only a few degrees away, I was amazed at the amount of nebulosity I could actually see. All the stars in the region were pin-point perfect, and the only hint of CA I could detect as I scanned the surrounding area was, not surprisingly, with Sirius. Next The Pleiades. Wonderful with the zoom at 21x but even better with my Meade 5000 32mm Plossl. This was the first time I had seen the whole of The Pleiades through a telescope, and framed against the blackness, the cluster looked fabulous. It was worth buying the scope just for this. With a 41mm Panoptic, the true field of view is well over 5 deg and I do not think it would be any insult to that venerable eyepiece to couple it with the RFT905. Meantime, I will have to make do with my set of 2-inch Revelation Widefields which are still pretty good. So far so very good. But what about using the scope outside it's natural comfort zone. As the sky was dominated by a Moon 6 days away from full, I decided to test the scope on our nearest celestial neighbour using a Meade 8.8 UWA married to a Baader Fringe Killer and a decent 1.5x Barlow. The combination delivered around 85x with a true Fov of over 1 deg. Granted there was some unobtrusive purple fringing around the Moon's intensely sunlit horizon, but there was nothing at all to detract from the clarity and stark detail of the landscape across the terminator and in and around Plato and Copernicus in particular. If conditions had allowed (the wind was now gusting up to 20 mph) I am sure I could have pushed the scope up to 140x or more - twice what Teleskop Express recommend for this scope. All short tube achromats are subject to CA, but to my eyes, the optics of this scope are very well corrected and with the fringe-killer, the CA can be managed down to well below nuisance level.

Conclusion

I have been a serious amateur astronomer for about 5 years - but I claim to great observing expertise. My purpose is just to enjoy the night sky. I have done so with a variety of scopes, currently a C12 and a 6-inch long-focal-length reflector, and now unquestionably with the RFT905, which for a very modest sum punches well above its weight and will be my permanent travelling companion. As soon as the seeing gets half-way decent, I shall even try it out on Jupiter and Saturn. But what I shall most enjoy is using it to voyage the Milky Way in great swathes, and visiting The Pleiades as often as I can. I heartily recommend this telescope.

[russ]

Great review. A member of our local club has this scope and its given some very impressive, and immersive, widefield views. Travelling along the Milkyway last summer was a treat using a 24mm Meade 5000 UWA. Picked out all the amazing deepsky treats low on the Southern horizon.

Enjoy your scope  

[emadmoussa]

Photos?

[Alfian]

Hi Dooshka, great review - considering it myself now - at the price its really tempting.