TMB 115 LZOS

[garryblueboy]

A very nice TMB 115 LZOS F7 has arrived thanks to a fellow Astronomer looking to Gain more Aperture so my LX went to a new home and this came home with me it is one of the original TMB with LZOS lens and feather touch focuser all in immaculate condition not to much out their in these scopes but everything I read was positive so looking forward to first light 

[dweller25]

Nice ?

[John]

Lovely scope

Looks like a slightly smaller version of my TMB/LZOS 130mm F/9.2. Does yours have the Kruppax tube ?

[garryblueboy]

 

15 minutes ago, John said:

Lovely scope

Looks like a slightly smaller version of my TMB/LZOS 130mm F/9.2. Does yours have the Kruppax tube ?

I’m not sure John it’s a early TMB not APM 

[John]

It looks pretty much exactly the same build as my scope, which has an APM label on the tube but TMB on the objective bezel and dew shield. My tube is Kruppax.

My scope dates from 2006 according to the optical test certificate.

[garryblueboy]

John Is there any well to tell ?

[DirkSteele]

That looks identical to my TMB LZOS 115 f/7 that I purchased in 2004 right down to the low budget tube rings (which are perfectly serviceable but not as nice as the CNC rings that come with these scopes now).  Mine is lens cell 142.  I reviewed it last year on the link below.  They are great scopes.  I always thought this vintage came in an aluminium tube and Kruppax was introduced a couple of years later.

http://alpha-lyrae.co.uk/2018/06/03/apm-lzos-115-triplet-apo-refractor-review/

While the tube and focuser are perfectly good, I had APM do a complete rebuild earlier this year with a 3" feathertouch which actually cost a small fortune.  I still have the old tube so will compare the new to old and see if there is a difference.

[John]

21 minutes ago, garryblueboy said:

John Is there any well to tell ?

If you gently tap the tube it sounds a little different to aluminium / steel. More like fibreglass I guess. Yours maybe aluminium though as Matthew says.

[mikeDnight]

4 hours ago, garryblueboy said:

A very nice TMB 115 LZOS F7 has arrived thanks to a fellow Astronomer looking to Gain more Aperture so my LX went to a new home and this came home with me it is one of the original TMB with LZOS lens and feather touch focuser all in immaculate condition not to much out their in these scopes but everything I read was positive so looking forward to first light 

That's a beautiful looking scope Gary!

Is it just me, or does anybody else want to lick that lens?

[garryblueboy]

6 minutes ago, mikeDnight said:

That's a beautiful looking scope Gary!

Is it just me, or does anybody else want to lick that lens?

Yes Mike it is delicious ? 

[garryblueboy]

24 minutes ago, DirkSteele said:

That looks identical to my TMB LZOS 115 f/7 that I purchased in 2004 right down to the low budget tube rings (which are perfectly serviceable but not as nice as the CNC rings that come with these scopes now).  Mine is lens cell 142.  I reviewed it last year on the link below.  They are great scopes.  I always thought this vintage came in an aluminium tube and Kruppax was introduced a couple of years later.

http://alpha-lyrae.co.uk/2018/06/03/apm-lzos-115-triplet-apo-refractor-review/

While the tube and focuser are perfectly good, I had APM do a complete rebuild earlier this year with a 3" feathertouch which actually cost a small fortune.  I still have the old tube so will compare the new to old and see if there is a difference.

Hi Mathew yes I read your review it was one of the reasons I went for it 

[Ben the Ignorant]

4 hours ago, garryblueboy said:

not to much out their in these scopes but everything I read was positive

When racking in and out of focus you will see this.

White even disks, what a true apo should show.

 

Yeah, Rohr's lab measured its Strehl ratios in five colors instead of the usual three and they are between 0.94 and 0.99. What is most striking is the three central colors in the spectrum, green, blue-green and yellow-orange are focused exactly at the same point, with zero split between them when it's measured in microns. Only the indigo/violet stands 5 microns away, and red 20 microns on the other side. Starting at 150 microns a refractor is considered apo.

My 80mm triplet has 23µ between red and violet so the same figure achieved with larger lenses is a rare feat. Must be that the three lenses are made of exotic glass. Figuring (Foucault test) and polishing (Lyot) are excellent or the 94%-plus polystrehl couldn't be reached. There is no light scattering to speak of, all of it is tightly packed where it should. Spherical aberration is nil.

The scope is a super-apo because its color spread is less than the humanly perceivable 40 microns, and a keeper.

https://astro-foren.de/index.php?thread/11698-lzos-apo-115-805-354/

[garryblueboy]

5 minutes ago, Ben the Ignorant said:

When racking in and out of focus you will see this.

White even disks, what a true apo should show.

 

Yeah, Rohr's lab measured its Strehl ratios in five colors instead of the usual three and they are between 0.94 and 0.99. What is most striking is the three central colors in the spectrum, green, blue-green and yellow-orange are focused exactly at the same point, with zero split between them when it's measured in microns. Only the indigo/violet stands 5 microns away, and red 20 microns on the other side. Starting at 150 microns a refractor is considered apo.

My 80mm triplet has 23µ between red and violet so the same figure achieved with larger lenses is a rare feat. Must be that the three lenses are made of exotic glass. Figuring (Foucault test) and polishing (Lyot) are excellent or the 94%-plus polystrehl couldn't be reached. There is no light scattering to speak of, all of it is tightly packed where it should. Spherical aberration is nil.

The scope is a super-apo because its color spread is less than the humanly perceivable 40 microns, and a keeper.

https://astro-foren.de/index.php?thread/11698-lzos-apo-115-805-354/

Thanks Ben I knew the LZOS were supposed to be good but didn’t realise they were that good ?happy days 

[John]

I think LZOS make some of the very best objectives available to the amateur. Unusually (uniquely ?) they control the whole process from the glass melt through to final polishing and mounting in bespoke objective cells. They use their own glass types which they rarely make available to other manufacturers and utilise hand finishing and frequent testing through the whole process. Thats why they are expensive

My 130mm TMB/LZOS has an F/9.2 triplet in it which is the best objective that I've ever observed through, and that includes my Tak FC-100DL.

When tested by Rohr and others, LZOS objectives often prove a little better than the test reports that are supplied with them.

 

[garryblueboy]

On 05/04/2019 at 15:38, John said:

It looks pretty much exactly the same build as my scope, which has an APM label on the tube but TMB on the objective bezel and dew shield. My tube is Kruppax.

My scope dates from 2006 according to the optical test certificate.

Hi John I think it may be when gently tapping it does sound like non metallic and doesn’t feel as cold if that makes sense 

[John]

6 hours ago, garryblueboy said:

Hi John I think it may be when gently tapping it does sound like non metallic and doesn’t feel as cold if that makes sense 

That does sound like a Kruppax 50 tube. One additional benefit is that this material seems make the scope immune from dewing. I think Matthew said this in his review and I've found that with my 130.

 

[Gabby76]

Congratulations on the new TMB, a very nice refractor. 

I had the Stellarvue/ TMB 115T and it was a outstanding telescope. 

[Ben the Ignorant]

A few more words about the color correction. LZOS' engineers chose to group all the colors except red within 5 microns of each other, red being 20 microns away.

The question of optimizing a visual refractor for the blue end or the red end arises sometimes, especially in Cloudy Nights. Some say red carries more interesting information but seeing planetary images in narrowly filtered colors, it's obvious each carries important info, so what spectrum end should be privileged? Not that this is a big difference here with only 25 microns total but apos with 115 or 150 microns chromatic spread need to be optimized for a group of colors over the other. When focusing on the brighter green fringe of the spectrum, which we do unconsciously because of the eye's natural sensitivity, the far ends are not as sharply focused.

Red is less disturbed by turbulence so you can be a little more lax with it. Images are steadier though a red filter, and some imagers filter their guidescope in red to benefit from that. But if the lens is not optimized for blue that imperfection adds up to turbulence, so the more sensible design choice is to group green and blue close together, and leave red a little farther away.

Which they did. So, eventhough the red spread is only an imperceptible 20 microns here they shot for the best correction. I'd love to own of these 115mm; I won't because it doesn't rain sapphires and silver coins but I admire the design.

[garryblueboy]

Thanks Guys for all the positive info looks like I got a Bargain and as usual clouds everywhere looking forward to trying it out 

[mert]

Garry’s scopes always make me want to buy something  lol 

[F15Rules]

12 hours ago, garryblueboy said:

Thanks Guys for all the positive info looks like I got a Bargain and as usual clouds everywhere looking forward to trying it out 

That's a lovely refractor Garry, I think the Russian blue coatings are the nicest to look at ..quite "lickable", even.

I remember holding one of these some years ago in Worcestershire (am pretty sure it was a 115mm), when I went to view a different scope and saw the TMB sitting on a table. The owner said it was a great scope but he didn't use it much as it was so heavy. He invited me to pick it up, and it was indeed really heavy- as I recall, MUCH heavier than my FS128 doublet which is a larger but lighter scope. That was the first time I had held a triplet and the weight difference really shocked me.

I'm sure this will be a fabulous scope for you..maybe one to hang on to?

Look forward to your first light report!

Dave

 

[garryblueboy]

1 hour ago, F15Rules said:

That's a lovely refractor Garry, I think the Russian blue coatings are the nicest to look at ..quite "lickable", even.

I remember holding one of these some years ago in Worcestershire (am pretty sure it was a 115mm), when I went to view a different scope and saw the TMB sitting on a table. The owner said it was a great scope but he didn't use it much as it was so heavy. He invited me to pick it up, and it was indeed really heavy- as I recall, MUCH heavier than my FS128 doublet which is a larger but lighter scope. That was the first time I had held a triplet and the weight difference really shocked me.

I'm sure this will be a fabulous scope for you..maybe one to hang on to?

Look forward to your first light report!

Dave

 

Dave this is the light weight version with the Kruppax tube so not so heavy I remember the Meade 115 6000 I had that was fairly heavy scope but yes I’m hoping to settle down now with the three scopes I have but you never know what comes up lol ? but it would need to be something special as the three I have are 

[garryblueboy]

1 hour ago, mert said:

Garry’s scopes always make me want to buy something  lol 

There’s some great deals out there Mert treat yourself 

[John]

The LW versions of these scopes are not too heavy for their apertures I feel. My 130mm F/9.25 weighs just over 9kg including rings, finder and diagonal. The original TMB CNC versions are a lot heavier.

 

[pmlogg]

Yes, the original Silver and White CNC models are heavy and the non-standard threads do pose issues at time.  Markus at APM is however quite receptive and will produce adapters (e.g. for flatteners and reducers).  Great scopes though.