Televue 76?

[DirkSteele]

I already own two 4” class triplet Apos, the APM TMB 105 being my airline portable set up (the OTA, diagonal and EPs will fit in carry on luggage), but on some trips that scope is still a little bit big. Especially when factoring in the tripod and mount needed to give it a stable platform (the scope fully loaded with a Televue 2” hand grenade on the back will be tipping the scales at 6.5-7kg. So now I find myself considering something even smaller, just for those times when the 105 is still too much to carry, almost something that could be (very carefully) thrown in a back pack with a couple of EPs and a very lightweight tripod and mount.

I find myself considering the Televue 76. I am very discerning when it comes to optically quality, having been somewhat spoilt by my 3 triplet Apos which are of the highest order in optical quality. So for anyone who is familiar with the diminutive little 76, how does it stack up? I have been lucky enough to use the NP 101 so I know what Televue is capable of, so any comparisons in performance to that would help (quality of image rather than how deep it goes, 3” is never going to stand up to 4”).

Also, I have been unable to find the minimum dimensions for transportation so if anyone has those to hand that would be great. What is the easiest way to attach it to vixen style dovetail?

If there are any other recommendations of scope, I am more than happy to hear them as well. I would like the scope to optically excellent and as small and light as can be. This instrument would be used pretty infrequently so if there is cheaper, but equal option, it would be nice to know.

I look forward to hearing your thoughts.

[glowjet]

There are a couple of Refractor reviews on the Cloudy Nights forum which sing the praises of the TV 76 / 480 F/6.3. Used in this country by one observer, claiming in the order of 100X per inch on a specially clear night in Scotland. Is the new SW Espirit triplet 80 / 400 F/5 outside your budget perhaps ?

[DirkSteele]

I wonder how much the Skywatcher Esprit 80 will cost? Took a look on FLO, but currently listed as "please contact us." Certainly another to consider. And thank you as I was unaware there was an 80mm model in the Esprit line up.

[RT65CB-SWL]

Quote "...Also, I have been unable to find the minimum dimensions for transportation so if anyone has those to hand that would be great.  What is the easiest way to attach it to vixen style dovetail?"

TeleVue teamed up with Vixen and made a plate for use with the Tele-Pod and Porta mounts. (I cannot find it on the TeleVue website, so I cannot give you the model number). I use one with a Ranger on Giro II.

The TV Pronto (70mm)(which is the same spec as the Ranger but with r&p as opposed to helical focusser) 76 & TV85 all had/have a clamshell and I think the mounting plate is also suitable for mounting them too.

Just to finish off, the Ranger and Pronto are 480mm in length and the TV76 is slightly longer.

[Ben Ritchie]

So for anyone who is familiar with the diminutive little 76, how does it stack up? I have been lucky enough to use the NP 101 so I know what Televue is capable of, so any comparisons in performance to that would help (quality of image rather than how deep it goes, 3” is never going to stand up to 4”).

Also, I have been unable to find the minimum dimensions for transportation so if anyone has those to hand that would be great. What is the easiest way to attach it to vixen style dovetail?

If there are any other recommendations of scope, I am more than happy to hear them as well. I would like the scope to optically excellent and as small and light as can be.

I love mine, wouldn't part with it, and the optics are everything you would expect of TeleVue - I don't have any meaningful criticism of the optics in mine. Focuser is terrific too, mine has the duel speed version which is very solid indeed. But if you want your 'scope to be as light as can be, don't buy a TV76 - it is built like a tank, and is consequently heavy compared to other telescopes of similar aperture. Saying that, it's not bad in absolute terms and fairly compact, so not like a big 5" or 6" refractor where you have a lot of weight out at both ends in the lens cell and focuser.

Mine has a clamshell that bolts to a standard dovetail, I have an ADM Vixen-style one. I can take measurements if you want to know exact dimensions. The clamshell is fine for visual, but there's a little flexure in there for imaging (not helped by the weight of the 'scope) so I use a pair of standard rings if I want it to be rigid.

If you want ultra lightweight portable then i'd look at the Borg 'scopes, the modular system breaks down into almost nothing and the components weigh very little too. Can't think of anything else that compares. Not in the same league optically as TeleVue, but still a perfectly respectable performer.

[Stu]

Have you considered a Tak? I don't know much about them other than by reputation on the forum. As you know from our conversations, I'm really happy with my TV76, but I believe the commonly held view is that Tak scope optics are a higher quality. As you like your optics pretty much perfect, I wonder whether it is worth a look? The Sky 90 perhaps?

Stu

[NGC 1502]

"what is the easiest way to attach it to vixen style dovetail ?"

The part you need is AVT-1011, at the bottom of this link - http://www.televue.com/engine/TV3b_page.asp?id=43

Or you could make one from a short piece of standard dovetail, drilled to the same spacing as the TV clamshell. You will need two screws to attach it, the same thread as you find on a photo tripod, 1/4" 20 tpi (whitworth). I did just this to attach my TV Pronto to my alt-az mount.

Regards, Ed.

[Stu]

I've got an ADM dovetail with a slot in it and just bolt this to the clamshell. Seems to work very well.

Stu

[Ben Ritchie]

I've got an ADM dovetail with a slot in it and just bolt this to the clamshell. Seems to work very well.

Same here.

Have you considered a Tak?

Good idea - depending on how much aperture you want, the Tak FS60C is a great option, very light and lovely optics. There's an element of Tak adapter-hell as there's very little focuser travel, so most of the time there's something that won't reach focus, but you learn to live with its quirks. Along with my TMB 80/480 it's top of the list of 'scopes I should never have parted with.

[E621Keith]

Good idea - depending on how much aperture you want, the Tak FS60C is a great option, very light and lovely optics. There's an element of Tak adapter-hell as there's very little focuser travel, so most of the time there's something that won't reach focus, but you learn to live with its quirks. Along with my TMB 80/480 it's top of the list of 'scopes I should never have parted with.

Also consider the Takahashi FC-76DC. Fluroite doublet and almost £300 cheaper than the TV76. If money is not an issue, the FC76DS with bigger tube and 2.6" focuser is only £70 more than TV76

http://www.iankingimaging.com/show_product.php?id=1408

Markus from APM posted on CN a few months a go about a new (but limited) stock of LOMO 80/480. May be it's worth sending him a email since OP seems to like APM triplet a lot.

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5737904/Main/5607913

[rowan46]

That lomo gets rave reviews

[DirkSteele]

Awesome, thanks everyone. Plenty to think about and investigate.

Clear skies,

[RT65CB-SWL]

Quote "The part you need is AVT-1011, at the bottom of this link - http://www.televue.c..._page.asp?id=43" - Yes, that's the one!

Thanks for locating the link Ed. I am using my phone to access the internet at present as I have to re-install the o/s's (Windows XP or Vista (maybe both) and Xubuntu). Something todo when its cloudy.

Regards,

Philip

[lardy]

Hi,

TMB92ss F5.5 .. not light but very compact ( 13.2" long ) with excellent optics and a 3" featherlight focuser. Not had first light with mine yet as waiting for the CNC rings to arrive from the States ( could I find 114mm CNC rings in the UK! )

I considered the APM 80/480 but wanted something a little faster and more compact but with comparable optics to my APM's. The TMB kinda ticked the boxes for me.

Have you done that report yet about your APM Matthew?

[DirkSteele]

Hi,

TMB92ss F5.5 .. not light but very compact ( 13.2" long ) with excellent optics and a 3" featherlight focuser. Not had first light with mine yet as waiting for the CNC rings to arrive from the States ( could I find 114mm CNC rings in the UK! )

I considered the APM 80/480 but wanted something a little faster and more compact but with comparable optics to my APM's. The TMB kinda ticked the boxes for me.

Have you done that report yet about your APM Matthew?

Thanks for the suggestion. Another to certainly consider. I recall reading an excellent review in Sky & Telescope a few years ago.

Report not yet done. But don't worry, it is coming. I have a few thread planned around it actually...

[E621Keith]

Hi,

TMB92ss F5.5 .. not light but very compact ( 13.2" long ) with excellent optics and a 3" featherlight focuser. Not had first light with mine yet as waiting for the CNC rings to arrive from the States ( could I find 114mm CNC rings in the UK! )

I considered the APM 80/480 but wanted something a little faster and more compact but with comparable optics to my APM's. The TMB kinda ticked the boxes for me.

Have you done that report yet about your APM Matthew?

Just out of interest. Is the TMB92SS in the same league as the premium Russian and Japanese scopes like APM and Takahashi? After all, like other post Thomas Back TMB scopes, the 92SS uses Chinese optics.

[michael.h.f.wilkinson]

I have an APM 80mm F=480 triplet (not the LOMO), and it is very good indeed. These scopes are sold in various guises (TS, Altair), and give pinpoint starts across the FOV (of the 31T5 Panzerfaust ). Olly Penrice had a look through mine and liked the views (though he may have been trying to be polite ). Not too expensive either, as these scopes go.