Dilemma

[ST_Steve]

So….

I have been saving for a new StellaMira 125mm ED Doublet f/7.8 and close to purchase but a friend of a colleague has offered me an APM LZOS 100/800 F8 Triplet APO for £2000.

The APM is only twelve months old and has barely been used and looks immaculate (the owner is giving up the hobby due to illness).

So here is the dilemma, stay with my original choice and extra aperture or go for the APM?

For information I’m visual only and already own an 8” classical cassegrain and Rowan AZ100 on BB Planet.

Anyone have any thoughts as my mind is in turmoil at the moment?

[mikeDnight]

I think I may be leaning toward the LZOS, not because its a triplet but because of the optical quality. It may take a little longer to cool, but it may very well punch well above its aperture class in terms of definition and image sharpness.

[JeremyS]

LZOS

[John]

I suppose the question is, would the APM/LZOS deliver what you were aiming to get from the 125mm Stellalyra ?

Although it's optics will perform about as good as 100mm can (it's in the top tier of 100mm refractors IMHO) 25mm is a lot to catch up, even for the magic of LZOS glass.

The Stellalyra may well cool quicker and the optical tube may even weigh the same but do you want what a good 125mm refractor can deliver or what a top tier 100mm can deliver ?

It's quite a finely balanced decision in some ways.

 

 

[ST_Steve]

My heart is saying LZOS but a finely balanced decision as you say @John and everyone’s comments have already crossed my mind. 
Does everyone feel the £2k price is about right? I don’t really want to haggle as the seller has a terminal diagnosis.

[Stu]

I guess my view would be you can ‘always’ pick up a SL 125 but won’t have many/any other opportunities to pick up an LZOS (assuming the price is right which I can’t comment on). I would go with the LZOS, knowing you could sell it on, or carry on saving to add the SL later 🤪🤣

[Captain Scarlet]

LZOS no question. If it’s the wrong choice, you’ll have no problem passing it along at no cost.

M

[Paz]

Assuming £2k for the LZOs id a good price, its only a good thing if you actually want one.

I agree with John's comment re what is the aim of having a SM125 and would the LZOs do better.

The SM125 does well in terms of price, weight, aperture, cool down, and quality.

I'm sure the LZOs is better quality but aperture counts for a lot also. I admit, if I was going to go for a top of the range 4" for visual I'd go for a doublet e.g. a  Tak[censored]i and just wait for one to come along second hand. You would have epic quality and even less weight and faster cool down etc.

I have a SM125 and a C8 and I think they cover different bases so having one doesnt make the other redundant, but a 4" is even further from a C8 so there's less risk of those scopes  competing for attention.

[josefk]

I would also vote for the LZOS Steve. 
Like you I have an 8”CC on an AZ100 and BB planet. a brilliant set-up.  I also have a 130mm APO and it competes with the CC. It also beats it on certain targets TBH but in raw capability rather than aesthetic pleasure the APO doesn’t take me into new territory. 
 

On the other hand I have an 85mm APO and that does things for me the other two can’t do because it can be out and in use at just a few minutes notice and can travel with me. I could mount it on the AZ200 but I can also mount it much more lightly for shorter sessions and do. 
 

In short IME/IMHO the smaller APO is a better compliment to my CC than the larger one. 
 

PS. I should qualify I don’t know the respective weights and mounting needs of the 100/800 LZOS and SM125. Possibly my experience of the option for lightly mounting for a fully different way to use the smaller scope doesn’t apply. 

Edited March 5 by josefk
Added PS.

[Moonlit Night]

LZOS 

[IB20]

At 5.6kg (I think) and 30-60 minute cooldown in Winter then I guess it depends what you’d want it for? Optically it’ll be near perfection though but won’t show more than the 125. I guess if you want a LZOS, go for it. The price seems about 50% rrp from when they were available so seems a good deal. You’ll almost certainly end up acquiring a 5 or 6” apo in the future with the az100 anyway. 😅

You could get a Starfield 102mm and the SM125 for £2k…

Edited March 5 by IB20

[John]

On the subject of the cost, the APM/LZOS 100mm F/8 triplets seem to retail new for around £4K so 50% of that for a 12 month old one, presumably in excellent condition, is a very fair price indeed. If you decide that it is not quite what you want at some point in the future I'm sure you will have no problem recouping your full investment.

 

 

[DirkSteele]

Sounds like a good price for one of the finest 4” scopes ever to be made available to the amateur astronomy community. You can almost certainly sell it on for no financial loss (and possibly at a profit) if it does not deliver all you hope it will.

With geopolitics what they are, new ones are not available anymore and possibly never will be again so I would not pass on the opportunity and that is coming from someone who owns 4 LZOS made triplets.

Edited March 5 by DirkSteele
Typo

[ST_Steve]

Okay, thanks to everyone who has expressed an opinion. What has come out of the comments has really confirmed my own thoughts, I think I just needed to hear a second (or more!) opinion and perhaps gain some perspective.

I started this search for an additional scope with a Starfield 102 in mind, then changed tack with the reports of the SM125, so I suppose in a way I’m going back to the 4” class I was originally considering as a complement to the 8” CC…

I do have a little ST80 for a fun grab and go option. I am also aware of the longer cool down time for the triplet over a doublet. My intention is to sleep on it and make a decision tomorrow. Will let you all know what I finally decide to do.

 Thanks again all 👏

Steve

[M40]

Just to add my thoughts, ignoring the cost aspect, the two are very similar weights but very different lengths. As you are looking at visual the eyepiece in the lzos would be easier to use as you aproach zenith. At the same time, using baader glass, M45 sparkles in the sm125 🤣

[John]

There is a certain attraction to owning and using what is widely acknowledged to be a top class refractor. It almost defies logic at times but there is a quiet satisfaction to be had when observing an astronomical target with some confidence that the views you are getting are probably as good as any instrument of that aperture can give under the pertaining conditions.

I had the opportunity to purchase such a scope back in 2016. I ended up buying two, one of which had a LZOS objective 🙄

 

[John]

You may well have seen this already - it is Roger Vine's report, on his excellent "Scopeviews" website, comparing a LZOS 100mm F/8 with a Celestron C8. Admittedly much older scopes than the one that you are considering but I don't think the LZOS 100 F8's have changed much recently:

TMB 100/800 vs C8 Review (scopeviews.co.uk)

 

Edited March 6 by John

[Deadlake]

I have a LZOS 105 mm @ f 6.25.

As many have stated it provides super sharp, high contrast views when the cloud allows.

Does it give up some aperture to a 130 mm version, of course however there is some thing about the sharpness and the brightness of the lens to the eye that makes you not want to give it up, I do not know why the previous owner did…

[JeremyS]

No pressure @ST_Steve 🤣

[John]

7 minutes ago, JeremyS said:

No pressure @ST_Steve 🤣

I tried to be as balanced as I could with my early post in this thread.

That didn't last long, did it ? 🤣

[ST_Steve]

I had already made up my mind before reading these replies @JeremyS @John @Deadlake 🤣🤣🤣 and haven’t changed my opinion since yesterday evening.

LZOS it is! I will be contacting the seller this afternoon.

Again thank you all for the balanced responses 👏 SGL really is a fantastic forum with wonderful members.

Steve
 

[Mr Spock]

You already have an 8"CC - what would a 125mm bring over that? What is your intended use? If it's a complement to the 8" then 4" would be a good choice. It would fit on a much lighter mount than the 125mm.

37 minutes ago, ST_Steve said:

LZOS it is! I will be contacting the seller this afternoon.

Sounds like you have the right plan!

[Piero]

Having already a 8", I would also go for the 4" refractor. This will also show a larger FOV at low power compared to the 125mm.

Adding the fact that you buy it second hand at a very fair price, to me the choice ia quite obvious!

[Moonlit Night]

6 hours ago, ST_Steve said:

I had already made up my mind before reading these replies @JeremyS @John @Deadlake 🤣🤣🤣 and haven’t changed my opinion since yesterday evening.

LZOS it is! I will be contacting the seller this afternoon.

Again thank you all for the balanced responses 👏 SGL really is a fantastic forum with wonderful members.

Steve
 

I think you have made the right decision. As has been previously stated:

A) The price is right 

b) These are not going to be imported back into the UK any time soon/ever (The last big import of TAL (Russian) refractors must be getting on for 15 years ago)

c) There is just something wonderfully reassuring about buying a premium refractor. Yes some of the reasons we buy these things is a little, dare I say… irrational, but you are no longer wondering if the glass is greener (or a nice purple or blue) on ABS. 

You could even argue (I’ve actually tested this out with Mrs Moonit) that it’s cheaper in the long run. The chances are you’re going to keep it forever if it ticks all your quality boxes. 
 
You’re not just buying a telescope, you’re peace of mind. 
 

Well done and congratulations. 
 

One another note, thanks for the appalling weather you are undoubtedly going to inflict on us all the moment you part with your cash! May include clouds, may nothing, it’s a given!

 

Edited March 6 by Moonlit Night

[Deadlake]

They do multiple