Refractor considerations

[Deadlake]

6 minutes ago, John said:

If I did not already have a TMB/LZOS 130mm I would have been onto that one 😀

I have got away with two 4 inch refractors but I suspect my other half will not see why two 5.1 inchers are "essential"

Don’t you need a 130 mm wide field scope as well? I’m running the argument thru my head I need a CAT (Mewlon) to complement my wide field scopes.....

[Captain Scarlet]

23 minutes ago, John said:

If I did not already have a TMB/LZOS 130mm I would have been onto that one 😀

I have got away with two 4 inch refractors but I suspect my other half will not see why two 5.1 inchers are "essential"

It's quite simple. It needs to be presented as an optimization problem. The correct number of scopes, obviously, = n+1, where n = no. scopes you own at present.

But also, the correct number of scopes = s-1, where s = no. scopes that would cause your partner to leave you.

Combining these, you get s = n+2. Which means your partner will only leave you if you get 2 more scopes. So there's room for just one more.

Ad infinitum...

Edited February 9, 2021 by Captain Magenta

[Peter Drew]

19 minutes ago, Deadlake said:

Don’t you need a 130 mm wide field scope as well? I’m running the argument thru my head I need a CAT (Mewlon) to complement my wide field scopes.....

Despite the mew in Mewlon, it's not a CAT it's a Dall-Kirkham Cassegrain.     😀

[John]

27 minutes ago, Deadlake said:

Don’t you need a 130 mm wide field scope as well? I’m running the argument thru my head I need a CAT (Mewlon) to complement my wide field scopes.....

Not really. I have the ED120 which is F/7.5

If I'm doing serious deep sky observing the 12 inch dob is as easy to get out as any of the refractors are.

If I have a gap it is probably in the 8 inch aperture area but I'd go for an 8 inch F/6 newt for that I think, if and when I decide to fill that spot.

 

Edited February 9, 2021 by John

[John]

14 minutes ago, Captain Magenta said:

It's quite simple. It needs to be presented as an optimization problem. The correct number of scopes, obviously, = n+1, where n = no. scopes you own at present.

But also, the correct number of scopes = s-1, where s = no. scopes that would cause your partner to leave you.

Combining these, you get s = n+2. Which means your partner will only leave you if you get 2 more scopes. So there's room for just one more.

Ad infinitum...

I'm on a 3 scope agreement with my other half and have been for some years. I'm on thin ice with the 6 scopes I currently own. She can count rather well !

 

[Deadlake]

11 minutes ago, Peter Drew said:

Despite the mew in Mewlon, it's not a CAT it's a Dall-Kirkham Cassegrain.     😀

Actually meant reflector, but failed at multitasking. C11 would also do...

[Nikodemuzz]

8 hours ago, Captain Magenta said:

There is a TMB 130 in the for sale section at the moment...

Thanks for the tip! TMB's reputation is right up there. They don't come up so much in discussions, but probably because they haven't been produced in a while and are pretty rare.

Edited February 10, 2021 by Nikodemuzz

[KP82]

4 hours ago, Nikodemuzz said:

Thanks for the tip! TMB's reputation is right up there. They don't come up so much in discussions, but probably because they haven't been produced in a while and are pretty rare.

The lenses in TMB SS scopes were not manufactured by LZOS but instead Canon Optron who also supplies lenses to Tak (uncofirmed). However the reviews I've seen so far are all very positive.

Edited February 10, 2021 by KP82

[John]

3 hours ago, KP82 said:

The lenses in TMB SS scopes were not manufactured by LZOS but instead Canon Optron who also supplies lenses to Tak (uncofirmed). However the reviews I've seen so far are all very positive.

I've seen a lot of discussions lately on the source of the optics for the TMB SS on another forum with no firm conclusion on the source other than that the objectives are excellent. 

I think it is pretty firmly established that Canon Optron provide the objectives for Takahashi and Vixen fluorite refractors. Maybe the non-fluorite Taks as well ?

With LZOS objectives, the objective cell is designed and manufactured by LZOS as well as the objective. Not sure if that is the case with other objective makers.

The TMB SS is a superb scope though, no doubt about that. Tom Trusock was very impressed with it:

https://www.cloudynights.com/articles/cat/cn-reports/telescope-reports/cn-report-tmb-130-signature-series-r1634

 

[KP82]

7 minutes ago, John said:

I've seen a lot of discussions lately on the source of the optics for the TMB SS on another forum with no firm conclusion on the source other than that the objectives are excellent. 

I think it is pretty firmly established that Canon Optron provide the objectives for Takahashi and Vixen fluorite refractors. Maybe the non-fluorite Taks as well ?

With LZOS objectives, the objective cell is designed and manufactured by LZOS as well as the objective. Not sure if that is the case with other objective makers.

The TMB SS is a superb scope though, no doubt about that. Tom Trusock was very impressed with it:

https://www.cloudynights.com/articles/cat/cn-reports/telescope-reports/cn-report-tmb-130-signature-series-r1634

 

I believe Tak source objectives from Canon Optron exclusively for their refractors whereas Vixen have scopes made both in Japan and China.

Yeah nobody knows for sure where the objectives in the TMB SS were sourced from. According to several threads on CN someone from Astronomics (TMB SS was a collaboration between Astronomics/Astro-tech & Mr. Back) claimed the objectives were made by a taiwanese optician who initially had set up  the business in Japanese but later moved back to Taiwan.

Most people who own the TMB SS 130 seem to be in love with it. That's why it's very difficult to find one on the used market.

[jetstream]

The TMB is a vg scope and that fella has vg optics...

[jetstream]

There is a strong connection between TMB and Markus Ludes https://astromart.com/forums/astronomy-equipment/equipment-talk/tmbs-designs

"Hi

many of the APM-LZOS Apo's are TMB designed and in production. But the TMB Business does not exist anymore , a reason why the product was renamed into APM-LZOS. Apm has anyway the owner ship on those TMB designs, since we paid TMB the design fees

cheers
Markus Ludes"

[jetstream]

The reason I mention this is two fold- obviously the current/historical connection between Ludes and LZOS but also that Markus Ludes most likely knows the source of the TMB SS lenses.

Maybe someone interested could contact him and ask?

I'm not a gambler but I'd put a lot of money on that he knows...

[John]

28 minutes ago, jetstream said:

There is a strong connection between TMB and Markus Ludes https://astromart.com/forums/astronomy-equipment/equipment-talk/tmbs-designs

"Hi

many of the APM-LZOS Apo's are TMB designed and in production. But the TMB Business does not exist anymore , a reason why the product was renamed into APM-LZOS. Apm has anyway the owner ship on those TMB designs, since we paid TMB the design fees

cheers
Markus Ludes"

Thomas M Back's passing in 2007 at just 50 years of age was a great loss to the refractor world

My TMB/LZOS is a 2006 model so bears the TMB engraving on the bezel. Later changed as Markus says, to APM.

 

[jetstream]

5 minutes ago, John said:

Thomas M Back's passing in 2007 at just 50 years of age was a great loss to the refractor world

A complete tragedy for the optics and astro community. He was well liked and respected by many.

[jetstream]

6 minutes ago, John said:

My TMB/LZOS is a 2006 model so bears the TMB engraving on the bezel. Later changed as Markus says, to APM.

Is this an offer to sell John? 😀

Maybe take my SW120ED as part trade?!

[Deadlake]

40 minutes ago, jetstream said:

The reason I mention this is two fold- obviously the current/historical connection between Ludes and LZOS but also that Markus Ludes most likely knows the source of the TMB SS lenses.

Maybe someone interested could contact him and ask?

I'm not a gambler but I'd put a lot of money on that he knows...

TMB 130 F7. This is one of the earliest Chinese made scopes from United Optics that was made for Thomas Back. Unless there are other TMB 130 F7 out there...
Thomas was partners with Markus at APM for the ‘TMB Apo’s using LZOS lenses, but TMB branded Chinese scopes are not related. They were a separate business that started and eventually closed after Thomas died. 

Jeff Morgan has one, he had some great NV pictures. LZOS are better and more expensive, the TMB is better value for sure.

Edited February 10, 2021 by Deadlake

[jetstream]

1 minute ago, Deadlake said:

TMB 130 F7. This is one of the earliest Chinese made scopes from United Optics that was made for Thomas Back. Unless there are other TMB 130 F7 out there...

 

I really don't know much about these scopes. I like known things.....like when it says LZOS on the cell or that Canon makes Tak lenses (common consensus anyway).

Do you know this for a certainty?

[Deadlake]

2 minutes ago, jetstream said:

I really don't know much about these scopes. I like known things.....like when it says LZOS on the cell or that Canon makes Tak lenses (common consensus anyway).

Do you know this for a certainty?

Let's say it came up while discussing buying a LZOS scope and would it also work with NV. I thought Jeff's scope was LZOS when its not.

Edited February 10, 2021 by Deadlake

[jetstream]

1 minute ago, Deadlake said:

Let's say it came up while discussing buying a LZOS scope and would it also work with NV. I thought Jeff's scope was LZOS when its not.

It is best to be educated when buying optics, very good info Deadlake-I didn't know this. Btw I personally dislike "clones" ....not saying the SS is, but I think you know what I mean.

[John]

Thomas had designed the 130 F/7's shortly before he passed away. He was excited about them as he posted here on the CN forum:

https://www.cloudynights.com/topic/78282-what-is-a-tmb-a-little-history/?p=1025809

Earlier in that thread he listed the lenses that he designed:

https://www.cloudynights.com/topic/78282-what-is-a-tmb-a-little-history/?p=1025627

Very sadly, less than a year later, he passed away.

I expect Markus Ludes does know the maker of the 130mm F/7 objectives. He was very helpful when I purchased my 130mm F/9.3 TMB/LZOS even though the last involvement he had with my scope was 10 years previously. Markus was able to supply me with the copies of the original paperwork and tests for my scope - he keeps them all on file apparently. The previous owner of my scope had lost the copies that had been supplied with the scope so I was glad to be able to get another set of them.

 

 

 

 

 

[Deadlake]

33 minutes ago, jetstream said:

It is best to be educated when buying optics, very good info Deadlake-I didn't know this. Btw I personally dislike "clones" ....not saying the SS is, but I think you know what I mean.

It was designed by Thomas Black, I would not call it a clone.

For telescopes I cannot think of any cloning, with the exception of Sharp Star copying Tak in the astrograph mirrored market.

However most of the cloning is the copying of Vixen and Tak mounts, thats for sure. You get what you pay for. Skywatcher and Optron are now going off on their own trajectory however...

 

Edited February 10, 2021 by Deadlake

[jetstream]

A portion of APM's reputation was built on the LZOS lens connection as well as Thomas Back's and priced accordingly.

APMs reputation might also have been used as a selling feature for their doublet ED scopes... if some of the discussions on these particular scopes were true then APM's reputation might not have been enhanced.

I think there were TMBII eyepieces that some called clones if I remember.

All I know is that going into a purchase its best with eyes wide open and being informed.

[Deadlake]

8 minutes ago, jetstream said:

APMs reputation might also have been used as a selling feature for their doublet ED scopes... if some of the discussions on these particular scopes were true then APM's reputation might not have been enhanced.

I suspect APM's reputation from LZOS has been used here, but in someway I'm not sure APM FPL51/53 scopes are any better then Skywatcher etc, given the price and manufacture.

As an aside for instance most diagonals are made by United Optics or GSO (Baader being the exception). However all the diagonals have different specs, from the same production line if you test them you will see different quality.

At the end just left with price to tell us if any good all other things being equal. 

[John]

5 minutes ago, Deadlake said:

....At the end just left with price to tell us if any good all other things being equal. 

And feedback from owners / users on forums ?

Sometimes you need to "read between the lines" but I've found that you can build up a reasonable picture if you read (critically) feedback.