Almost Ready For a 5" Frac!

[dweller25]

Telescope Service is a German company but they do ship overseas.

Edited December 29, 2022 by dweller25

[Deadlake]

I'm surprised the TEC140 has not been bought up....

LZOS are no longer available, even if the war was to stop tomorrow the cost of the lens cells is just too high Marcus has not proceeded. 

The main unique selling point of the AP130GTX apart from the figuring is the weight, which is why I would prefer an AP over the TOA130 that is a battleship. 

 

[ollypenrice]

As Deadlake says above, the TEC140...

You are within price range on the used market. It is a triplet but oil spaced, so there is physical contact between all objective surfaces, making cooldown fast. TEC QC is second to none, and I mean none. (As someone who hosts robotic telescopes I can tell you that Takahashi QC is abominable. If anyone feels inclined to burn me at the stake as a heretic for this, PM me for chapter and verse. Believe me, I'm ready.)

The TEC objective is optimized for visual observing (which you'll like) but, with flattener, it is also the best refractor - the best set of optics, in fact - that I have ever used for imaging. The focuser is Feathertouch rack and pinion. You will never beat that. I bought mine second hand about ten years ago and it performs, in all respects, as new.

We might remember that, when it appeared, it was presented as a slightly 'sub-premium' Apo with a clever design, and clever aperture choice, designed to take on the finest Apos and beat them on price. The fact that it is now regarded as a full-on premium Apo indicates that it proved capable of living with the best and, sometimes, beating 'the best.' I would swap mine... but only for an AP175. 

Olly

[Cjg]

Good luck in choosing @Sunshine!

I went to a 125mm as an increase in aperture from a Tak 76; a huge difference in "light gathering". 

My 125 is a doublet from a UK company called Altair Astro; the same scope is available from other retailers under differing brand names. 

This is a slightly newer version with a handle included ,though the scope  OTA, I think, is the same  as mine https://www.altairastro.com/altair-wave-series-125-edf-f78-apo-w-large-m92-rp-focuser-454-p.asp Mine came with a test report and has a Strehl ratio of 96.6

No noticeable 'cool down' time needed, but I tend to drive to Seething Observatory (the home of Norwich Astro - my local club) with the heating off, or on a minimal amount.

Am not sure if you plan on using your existing mount, but a frac of this size and weight needs careful balancing at the start and handling, especially at the end of a session when you are cold / tired packing away.  I use an Alt Az manual mount that needs counterweights, so more time to set up / take down.

I upgraded my Tak to a 92mm Stowaway, and it really depends upon the weather forecast as to which gets used...if the weather forecast is for clear skies for most of the night, then it's the 125mm that accompanies me, but, if the forecast is less than settled, then it's the Stowaway.

Looking forward to seeing what you go for!

Chris

[Sunshine]

8 minutes ago, Cjg said:

Good luck in choosing @Sunshine!

I went to a 125mm as an increase in aperture from a Tak 76; a huge difference in "light gathering". 

My 125 is a doublet from a UK company called Altair Astro; the same scope is available from other retailers under differing brand names. 

This is a slightly newer version with a handle included though the scope is OTA, I think, is the same https://www.altairastro.com/altair-wave-series-125-edf-f78-apo-w-large-m92-rp-focuser-454-p.asp

No noticeable 'cool down' time needed, but I tend to drive to Seething Observatory (the home of Norwich Astro - my local club) with the heating off, or on a minimal amount.

Am not sure if you plan on using your existing mount, but a frac of this size and weight needs careful balancing at the start and handling, especially at the end of a session when you are cold / tired packing away.  I use an Alt Az manual mount that needs counterweights, so more time to set up / take down.

I upgraded my Tak to a 92mm Stowaway, and it really depends upon the weather forecast as to which gets used...if the weather forecast is for clear skies for most of the night, then it's the 125mm that accompanies me, but, if the forecast is less than settled, then it's the Stowaway.

Good luck in choosing!

Chris

Thank you for the info! great to hear you are Happy with your Altair Astro 125, I decided not to rush headlong into a snap decision and prefer to gather input from those who have larger doublets and can speak from experience at the eyepiece.

Since you were nice enough to contribute (thanks) I will ask about your experience at the eyepiece, how are planetary views? I am not looking for triplet performance in a doublet but I would not enjoy glaring CA, a tad is fine. Many doublets good doublets seem to struggle with Mars, particularly.

UPDATE: Upon searching out your scope I found your SGL review from 2018 front and centre on google, funny part isI was the second person to leave a comment 😂 funny how we can forget.

Edited December 29, 2022 by Sunshine

[Deadlake]

What mount are you going to use?

[GazOC]

It's surprising from these pictures just how much difference in size the extra 7-8 mm in aperture makes from 120mm to 127mm for scopes of the same focal ratio 

[Sunshine]

1 hour ago, Deadlake said:

What mount are you going to use?

Me? I have an alt az mount capable of quite a bit more weight than the 125,  UA Doublestar tandem mount, it can take 35lbs on main saddle no issues.

[Franklin]

11 hours ago, F15Rules said:

That's 3 of the 4 that I know of in the UK..and one more I know of in Australia.

 

20 hours ago, Sunshine said:

It seems both yourself and F15Rules own the only two FS128's ever produced.🙄

The majority of FS128's ever produced are currently hiding in Japan.

[Cjg]

13 hours ago, Sunshine said:

Thank you for the info! great to hear you are Happy with your Altair Astro 125, I decided not to rush headlong into a snap decision and prefer to gather input from those who have larger doublets and can speak from experience at the eyepiece.

Since you were nice enough to contribute (thanks) I will ask about your experience at the eyepiece, how are planetary views? I am not looking for triplet performance in a doublet but I would not enjoy glaring CA, a tad is fine. Many doublets good doublets seem to struggle with Mars, particularly.

UPDATE: Upon searching out your scope I found your SGL review from 2018 front and centre on google, funny part isI was the second person to leave a comment 😂 funny how we can forget.

Good morning, 

The eyepiece experience is a much, much tougher question.

I've had many more hours with the 125 since my first light report, since July 2018.

The planets are great, Jupiter and Saturn have been superb, but not Mars. (Most recently looked at approx 2 weeks ago) it's too bright at present. I used my Panoptic 24mm and 9mm Nagler. I'll have another attempt when the weather improves, but at that time, it felt very much as if I needed an ND filter to "dim down' the brightness.

All of the comments have been about the Stowaway; ( https://www.facebook.com/groups/479353680354/posts/10166985478450355/ ) it's probably seen a little more action as the weather has been less than settled. If I had to keep just 1 scope, then it would be the Stowaway...

Probably no help whatsoever, sorry!!

Chris

 

[Sunshine]

4 hours ago, Cjg said:

Good morning, 

The eyepiece experience is a much, much tougher question.

I've had many more hours with the 125 since my first light report, since July 2018.

The planets are great, Jupiter and Saturn have been superb, but not Mars. (Most recently looked at approx 2 weeks ago) it's too bright at present. I used my Panoptic 24mm and 9mm Nagler. I'll have another attempt when the weather improves, but at that time, it felt very much as if I needed an ND filter to "dim down' the brightness.

All of the comments have been about the Stowaway; ( https://www.facebook.com/groups/479353680354/posts/10166985478450355/ ) it's probably seen a little more action as the weather has been less than settled. If I had to keep just 1 scope, then it would be the Stowaway...

Probably no help whatsoever, sorry!!

Chris

 

This Facebook post is somewhat of an eye opener, what strikes me is the fact that your stowaway seems to have stole the show, a sub4” refractor left people mesmerized at the view it produced. What you say about Mars in your post is also an eye opener, when I point my TSA-102 at mars even in mediocre seeing I see Mars, may be a bit shaky in mediocre seeing but I see surface detail and it’s color is always a bronzy orangy hard to describe Martian color, it’s wonderful. 

The 102 isn’t going anywhere, no matter what larger refractor I choose.

[Coco]

Big frac's are fun but keeping them steady isn't, Im going to build a garden pier for mine, my skytee II isn't really strong enough or tall enough  and my Omegon AZ & Manfrotto 161MK2B ok but has no slo mo controls. 

[Grotemobile]

I know this is not a refactor but this scope is one  of my most used. 6" Mac. Way better than my 4" vixen Doublet on the planets

 which is what l image  . Horses for courses . Have done imaging with both these scopes on the CG-5 mount .6" Mac is easier to use.

[F15Rules]

1 hour ago, Grotemobile said:

I know this is not a refactor but this scope is one  of my most used. 6" Mac. Way better than my 4" vixen Doublet on the planets

 which is what l image  . Horses for courses . Have done imaging with both these scopes on the CG-5 mount .6" Mac is easier to use.

A nice pair of scopes.

I'd expect the Mak to comfortably beat your Vixen..not perhaps a truly fair comparison though? Apo Vs Achromat.. now, if you compared an ED103s or SD103s Apo to your Mak I think the contest would be much closer, and the Vixen would also give you a significantly wider fov, not to mention faster cool down and lighter weight👍.

Btw, I really like Maks: if I couldn't have an Apo refractor I'd happily have a decent Mak..I had 150mmLomo Ylena and Intes Maks some years back and both were excellent.

Dave

 

Edited January 2, 2023 by F15Rules

[LDW1]

I have a 127mm refractor, it weighs about 22 lb. complete, its is a different animal than my 4 other refractors, it needs a different mount, its mount weighs over 20 lb. Its a great change with great views on the good nites, grab & go is not part of its forte but every astronomer should have tried one in their viewing lifetime !  PS:  Before they get too old, lol !