TS-Optics 8" f/12 Cassegrain telescope 203/2436 mm OTA

[johninderby]

Good, now you can use it properly. 👍🏻

[LoloCoAstro]

Hi,

I use my telescope with the diagonal, two days ago. It's ok !

Thanks again about your help.

I's very kind

[johninderby]

you are welcome. so much easier with a diagonal. 🙂

[Lamplighter05]

On 12/10/2019 at 10:46, johninderby said:

Minor jobs. 🙂

Got the finder aligned and found I needed the two inch spacer added to focus on something a mile away. 

Found the front cover was a bit awkward to remove as there was nothing to grab and it is a snug fit. So off to the spare parts box for a black stainless steel knob to attach to the cover. Much better. 👍🏻

I took the plunge and invested in one of these too - just arrived today. Very nice indeed. One thing I noticed about the front cover is that it 'locks' in place by twisting once placed into the OTA. Its about a 10 to 20 degree twist to 'lock' and 'unlock'.

[johninderby]

12 minutes ago, Lamplighter05 said:

I took the plunge and invested in one of these too - just arrived today. Very nice indeed. One thing I noticed about the front cover is that it 'locks' in place by twisting once placed into the OTA. Its about a 10 to 20 degree twist to 'lock' and 'unlock'.

Good to see another CC owner. 👍🏻👍🏻👍🏻

Yes I was impressed with the build quality of it. Very solid scope.  One thing I found was that sometimes it was difficult to remove the cover if you overtightened it  Hence the knob. 

[Lamplighter05]

16 hours ago, johninderby said:

Good to see another CC owner. 👍🏻👍🏻👍🏻

Yes I was impressed with the build quality of it. Very solid scope.  One thing I found was that sometimes it was difficult to remove the cover if you overtightened it  Hence the knob. 

Indeed, as I already had an TS APO 80mm triplet refractor and am very happy with the build of that, I was really happy to see, and conformed via your thread here this was my next option as opposed to a Mak. I'm looking to the autumn and winter for most of my telescope time ... dew and temperature plus CA my main concerns. Funnily, the CC I received has a red front tube baffle from the current RC as advertised. I did check I hadn't got some factory 'Frankenstein' hybrid - seems not - only cosmetic! Lol. My next 'investment' will be some Vixen to Losmandy mounting saddle, so I can use the broader rail on the mount side rather than the Vixen bar. I think your lid solution is a great addition.

Separately did you tweak the collimation in the end, if so what method did you use? Cheers for any info.

[johninderby]

I played around with the collimation just to see how you went about collimating it but the collimation was OK as delivered but now I know how to do it. Once you understand how to collimate it it is actually quite simple as explained in the manual. Don’t know why TS doesn’t provide a manual. 🤔

https://nimax-img.de/Produktdownloads/62478_1_Anleitung-EN.pdf

[nfotis]

Still on the fence about this and the Skymax 180. I don't like the spider vanes and the resulting diffraction pattern, but I suppose that for planetary observation and imaging these aren't a problem.

I have seen that the Omegon brand version is cheaper than the TS one, I wonder if there's any quality difference? Or different accessories? Also, the GSO site doesn't mention the classic Cassegrain series at all.

As I live in Athens, Greece dew and cold aren't usually a problem. Would a few shield be useful as a stray light block, though?

Since I have a HEQ5 mount, I suppose that I'll have to reverse the mounting rails in order to have the guide scope on top, right? Does this involve cutting holes as well?

Cheers,

N.F..

 

Edited September 16, 2020 by nfotis

[AstroNeb]

Throwing my hat in the ring.

Took delivery of a TS 8” Classical Cassegrain yesterday at 11am and had first light of Venus and crescent moon within an hour😀
I got it from Teleskop Service in Germany and pretty happy with scope and their service.

First problem is the OTA being 8.9Kg as opposed to the 7.5Kg advertised, have asked them to rectify this on the website for the benefit of others. Maybe without focuser and/or rails 7.5 is correct.

Second one, actually more of a ‘Doh!’ moment was spotting the StellaLyra at about £200 cheaper😢 I’ve convinced myself that this is because the StellaLyra claims 95% reflectivity of the mirrors and TS 99% (mmmm, they got the weight wrong so maybe...?)

Looking at the other manifestations of this beast (iOptron, GSO, Orion et al) 96% seems to be the usual figure which means I’m clinging to the hope that when these companies order their paint livery etc. from the factory in China, they either specify the coatings they want on the mirrors (to suit budget and pricing etc.) or coat the optics themselves.🤞

The scope is an ‘upgrade’ from my pristine 18 year old Intes MK67 (which I’ll be selling). The easier to handle and vastly cheaper 6” may have been a more suitable choice😢

But this scope seems very promising, just hope to goodness I don’t drop it.

Enough for now, it’s been a good distraction to losing a very close friend to Covid on Tuesday.

Keep safe everyone.

[johninderby]

A handle really helps.

The ADM is expensive bit fits right onto the dovetail on the top.

https://www.firstlightoptics.com/adm-misc-mounting-accessories/adm-dovetail-handle-vixen.html

The WDS handle is great though and much cheaper.

https://www.wdscomponents.com/en-gb/tubed-handle-front-mounted-black-wds-8517/c-404/p-920

 

[AstroNeb]

43 minutes ago, johninderby said:

A handle really helps.

The ADM is expensive bit fits right onto the dovetail on the top.

https://www.firstlightoptics.com/adm-misc-mounting-accessories/adm-dovetail-handle-vixen.html

The WDS handle is great though and much cheaper.

https://www.wdscomponents.com/en-gb/tubed-handle-front-mounted-black-wds-8517/c-404/p-920

 

Thanks JohninDerby, definitely going to fit something to help with the handling. Yes the WDS website is almost porn to me! Wonderful fittings to behold.👍🙂

[johninderby]

5 minutes ago, AstroNeb said:

Thanks JohninDerby, definitely going to fit something to help with the handling. Yes the WDS website is almost porn to me! Wonderful fittings to behold.👍🙂

Yes you can’t help adding a few extras that might come in handy while perusing the WDS website. 😁

[LoloCoAstro]

Last days, I try to adjust the collimation of my telescope. But I don't understand somethings.

When I use 3 screws on the secondary mirror, it's possible to adjust the collimation.

But is it possible to adjust the primor mirror ?

Behind the telescope there is 3 pairs of screws. How do these screws work ? Do they adjust the primor mirror or adjust the axe of the focuser ?

I ask you this because, when i adjusted the colimation, last time, I saw a little astigmatisme.
Do you know how to remove this astigmatisme, or decrease it ?

Do you tested it ?
Do you have some information to help me ?
 

[johninderby]

Have a read of the manual. Will explain collimation quite well.

https://nimax-img.de/Produktdownloads/62478_1_Anleitung-EN.pdf

[LoloCoAstro]

@johninderby,

Thanks. I have this manuel.

But i don't undestand.

The "Optical Axis (Primary Mirror) Adjustment" don't work on the primary mirror directly, but on the axis of extension rings and focuser. Are you alright with me ?

My question is: when we adjust the optical axis, the position between secondary mirror and primary mirro is it différent or is it the same ? So, the position of extension rings and focuser change from mirrors ?

 

 

 

[johninderby]

The adjustment screws around the back of the scope adjust the tilt of the primary mirror. The distance between the primary and secondary stays basicly the same as you will omly be making very small adjustments. 

These screws don’t adjust the tilt of the focuser / extensions.  To adjust the tilt of the focuser you need to add a tilt adjuster. 

https://www.teleskop-express.de/shop/product_info.php/info/p4272_TS-Optics-M90-Tilting-Adapter-Flange-for-astrophotography.html

I originaly thought these screws did adjust the tilt but have now found out that they don’t.

[LoloCoAstro]

Thanks @johninderby,

I think that you exactly undestood my problem.

7 hours ago, johninderby said:

These screws don’t adjust the tilt of the focuser / extensions.  To adjust the tilt of the focuser you need to add a tilt adjuster. 

https://www.teleskop-express.de/shop/product_info.php/info/p4272_TS-Optics-M90-Tilting-Adapter-Flange-for-astrophotography.html

The element with 3 pairs of screw on the back of the scope look like to this tiltin adapter flange. That's why I believed it.

Thanks so much. Next time I'll try to adjust the primary mirror too. 

[Stu1smartcookie]

This is the scope that i have wanted ... having bought and sold ( and lost loads of money ) trying to find my sweet spot in this wonderful hobby , i am at last happy ! 

Now , where are the planets ???? hmmm,  in the East in the morning  ... ah well , there are loads of doubles and a very nice moon to look at .   

Edited March 17, 2022 by Stu1smartcookie

[LoloCoAstro]

Hello evevrybody

Someone knows if it exist a optical reducer focal to the 8" F/12 ?

[nfotis]

I think that TS offers a 0.67 reducer suitable for this design.

Lemme see... Saw it in the accessories :

https://www.teleskop-express.de/shop/product_info.php/info/p8932_TS-Optics-Optics-2--CCD-Reducer-0-67x-for-RC---flatfield-telescopes-ab-F-8.html

N.F.

[magnahrl]

Intressting thread. I am very intressted to purchase a GSO CC8 f12.  Partly because it`s an open tube which maybe reduces cooldowntime and the problem with dew. I also like the eypiece is always easy to reach comparing to my 8" f/6  Newtonian. I can get one CC8 second hand which has only been set up 3 times but hardly used since the seller purchased it in 2021. The price is also attractive   -1/2 the money vs the cost new. Furthermore the seller has let me loan it before actually buying it. Very kind. I have had it out for 2 nights. They where a bit hazy but I could see brighter stars. It was  a bit out of collimation. I have never collimated a CC but it looks as I got right by using a 4mm hexwrench (?) on the secondary. Only tiny movements. I did not touch the primary. I noted some SA in startest but not more than one can expect on a massproduced telescope. No astigmatism, TDE or pinched optics. The seeing was rather mediocre so I was not able to determing the snap focus exactly.

I used one 2" extension ring + a 2"diagonal (WO). Mag I used were 100X, 185X, 267X, 300X ,343X and 400X for testing. Delta Cyg was sweet and well sep at 185X and 267X. Lot`s of black space between A-B.

The OTA is rather heavy vs my C8, close to 9-10kg is my guess (20lbs) Still my VixenGP+Celestron 2" steeltripodlegs held very solid for visual observing. And yes I am 100% visual. Damping time was ~3 sec after a light hit on the tube at 400X. On my C8 it`s  ~1sec.

What do I want to use this scope for? Well mainly multiple stars, planets,open clusters, globular clusters and planetary nebulas.

I would be happy to here opinions regarding my thinking on this 8"CC scope from you out there.....

Yes I know I have too many scopes. But I am very curious on this CC and the price is good? I  would not have considered I new one for full price! Maybe.......

 

Clear Skies!

Magnus A.

 

[magnahrl]

PS Or should I save money and get a Mewlon 180? Somewhere in the future.

Magnus A.

[josefk]

i have this scope @magnahrl and i really rate it. It has brought and does bring me a lot of pleasure.

That said in your family of scopes i'm not sure it brings any new capability versus the 6" Mak, 8" SCT and 8" newt you have??? In my family of scopes i would swap you my CC8 for your 6" Intes 🙂

The CC8 is a bit undersized (using the flashlight test) at 185mm ish and that makes the secondary a bit chunky in percentage terms and also using the flashlight test the secondary is anyway a bit bigger than specified.

Still, I really enjoy it's contrast and general capability (in a compact package) at medium magnifications on DSO (including planetary nebula) and collimation holds really well (i drive down a rough track to my viewing spot and it doesn't care). For planets the diffraction spikes are a big distraction (for me) and i think the quite thick secondary support (that makes collimation so robust) contribute to those spikes being fairly prominent on the brighter planets even while the details on the face of Jupiter in particular have at times been excellent.

[magnahrl]

Thanks josefk for your kind feedback.

Yeas the CC8 won`t bring new optical  capability to my  scope family but it  might bring me a better ergonomical scope than the 8" Newt. I don`t have to stand, I sit and relax for reaching the eypiece and turn the ota for comfortable view in the eypiece is not needed  and I don`t have to rebalacing the scope when looking at new objects. Maybe a good alt-az mount like Rowan or Losmandy AZ8 will make things easier but that will cost Money!!

My C8 and Intes MK66 are dewmagnets even with dewshields on. Indeed there are other ways to fight dew such as "dewbands" to put on the tube. But they need a battery and cables and I don`t want to mess in the dark with such things if I can get a fairly short tube were the optics are resonably protected from dew and the eypiece is as comfortable to use as in an SCT, Mak or refractor.

Still it hurts to stop using my excellent (?) 8" Newtonian. Just sell it you might say? Not easy to ship this. In my country the intresst in visual scopes is almost 0. People intressted in astronomy observing just don`t observe, they are imagening. So the demand for shortfocus apo:s is much higher. This might not be the truth   -it`s just my experience!

I have a small balcony were my C8 (1973) and MK66 are perfect. Yeas I do have the sad light-pollution but those two scopes work perfectly there on my Vixen GP +a Vixen light aluminum tripod. No dew thanks to the roof above my balcony. Still pretty good view of the E and S skies.

So there you have it why I want an easy to use scope with little dew problems and a comfortable to reach eypiece. I think CC8 could be the answer. I am 71 years now and I don`t want to give up observational astronomy yet out in the dark nature. My Equinox 120ED is also an instrument I want to use more in the dark sky. With a longer dewshield than the original.

Sorry for the long rambling.....

And yeas you are correct: my Intes MK66 Mak is a beautiful scope. Very nice views. Pinpoint stars up to ca 360X. Nice planetary views. My 1973 C8 is not so aestetecly nice in good seeing but still it resolvs tighter binaries and shows more and distinct details  on Jupiter, Mars and Saturn. An amazing 50+ years orange SCT C8 scope. I have deforked it and put a Vixenrail on instead so I can use it on my eq-mounts.

Once again sorry for the rambling.

 

All the best,

Magnus A.

 

PS  Is the Tak Mewlon 180 worth 2200€?

[magnahrl]

PS2  I have read Carlinos rewiew of a CC8 where he states the actual aperture is 7,3" and so the 33-34% CO is not correct. Thats bad! I am not so worried the aperture is 0;7" less than stated but the increased CO is irritating.

Magnus A.