RIP Tak Sky-90
Posted 15 March 2013 - 04:33 AM
Posted 15 March 2013 - 04:38 AM
I bought it second-handed for $750, including the flattener, because its front element was scratched.
It is giving me some old age problems lately.. like black paint inside falling like powder, weird corners on 35mm format, but I still love it.
Posted 15 March 2013 - 06:39 AM
Posted 15 March 2013 - 07:42 AM
It is the original "Stowaway"!
It was introduced after the Stowaway.
Posted 15 March 2013 - 08:50 AM
However where are the PICTURES?
Posted 15 March 2013 - 09:06 AM
Posted 16 March 2013 - 09:46 AM
Will miss the little guy.
I won't. I have had a Sky90IINSV with all the major accessories (FF, CAA, ext-Q, 2" adapter, etc) for almost 10 years (serial number in year 2005). It is not going anywhere but outside under the stars and doing solar with my solar filters. While it is NOT an f4.9 Stowaway, it is very close, and is always very happy coming along on vacation in the made-for-it Temba case.
Posted 16 March 2013 - 12:31 PM
Posted 16 March 2013 - 03:56 PM
The Temmon Guide review is in the Uncensored Tak Group > Files > Temmon_Guide > Sky_90_Review.
Sky 90 review
Now THAT is a review, not the puff pieces we see in the US mags.
Hummmmm, where can we find a translation of this article ?
I just acquired a used Sky90 a month ago, and I must admit that I felt in love with it !! True that in has a tiny amount of chromatism and some coma compared to the TMB 92, but it is sharper, has a superb contrast and color rendering, and the stars images are textbook ! Great little scope !!
Posted 17 March 2013 - 05:44 AM
I had bought one of these for spontaneously gazing at a few objects every once in a while, especially in cold winter temperatures when I normally would be too lazy to set up one of my bigger scopes.
In normal weather, it showed some CA (I wouldn't call this one a real Apo) but almost no SA: A nice little scope indeed.
However, in temperatures falling below 30F its objective lens started to show SA caused by being pinched in its lens cell obviously shrinking at a higher rate than the glass, thus deteriorating optical quality.
Since I had bought the Sky-90 especially for the cold season and due to its very obvious inferiority to my FCT100 (in every observing temperature!) it soon had to go...
As you know I'm very fond of Tak - however, in this case I considered the AP-Stowaway (which I in fact once had the opportunity to observe with) the clearly superior contender!
Posted 17 March 2013 - 08:02 AM
Actually your report is not the first time I heard this. I wonder why the Sky-90 behaves differently than say the FS-60 or the FC-76...
May be that the larger size is no suit for the same type of cell design?
Posted 17 March 2013 - 08:52 AM
The Sky 90 in its day really was a marvel and its excellent build quality, compact design and sharp optics, while admittedly showing CA, kept up well into the present. However, now there are plenty of less expensive options and even the Asian triplets can surpass this little gem(my TMB 92L showed less coma and less CA than my Sky 90!), so it comes as no surprise it is being dropped. Still, a great scope for visual in my book (loved it), but plenty of others get wrapped up with the color it shows and scoff (hate it)!
I'll have to agree with Tim here. I'd really like to see Takahashi focus on a larger FSQ from an imaging standpoint.
Posted 17 March 2013 - 08:55 AM
Posted 17 March 2013 - 09:06 AM
IIRC, the Sky 90 I didn't have the pinch problem but didn't hold collimation well. Sky 90 II was introduced in 2003 and had a different cell design that holds collimation well but pinches the optics when cold. It was later redeisgned and a different lens fixing glue was used to eliminate the pinch problem.
A friend and I bought our first ones at the same time in early 2004 and it still had the problem. Both were returned to Takahashi by TNR in late 2004. We received brand new 2005 OTAs in early 2005 which no longer had the cold pinch. It actually showed a 'snowflake' type of distortion in focus which turned to a haxagon the futher one traveled from the focal point.
It is an exceptionally nice little light telescope since the cell problem was fixed.
Posted 17 March 2013 - 08:39 PM
Yes, I read about those problems. My gripe was very poor wide field performance, despite the relatively enormous price tag. It is well known that the Sky -90 was the weak link in the Takahashi lineup.
Posted 18 March 2013 - 03:24 AM
Thanks Andy for the link showing the large air gap, this all makes sense now.
So basically if someone wants to buy a used one he should look for a serial number indicating a manufacturing date after 2005....
Any nice astro pictures that you could post, that were shot with the Sky-90? :photo:
Posted 04 April 2013 - 11:08 AM
They hinted a revival of fluorite objective lens scope in the future. Ok, nothing specific beyond that
Posted 05 April 2013 - 01:45 AM
Posted 05 April 2013 - 10:44 AM