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What is wrong with Takahashi ?


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My take on it is this: the FC-100DZ is already £2.5-£2.6k. Even an FC-120DZ (not as big a scope as you are suggesting) would cost at the very least £3.4k. And the TSA-120 triplet is only £500 more. With this scenario, can only conclude that there isn’t enough space or profitability in an DZ120. 
How much would a 130DZ cost? £4k? Is there a market at that price? 
I’d love them to extend the range, but I maybe it doesn’t stack up financially?

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How much was the FS128 when it was out, relative to a 100mm Takahashi? I suspect at 130 mm the TOA is popular as one of the best imagining scopes at that aperture and that's where the market is.

Note:


Takahashi should supply a lens report, LZOS and AP guarantee a minimum tolerance. 
TecnoStar also provides a minimum lens quality on their 130 mm model as well.

Edited by Deadlake
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21 minutes ago, dweller25 said:

Why are they not making an FC130DZ ?

..so that you're not tempted to sell your FS128 David??😈😂

But joking apart, could such a doublet really be noticeably better than the FS128?🤔

I know mine isn't going anywhere, for any other scope!🤗😊

Dave

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1 hour ago, Deadlake said:

Takahashi should supply a lens report, LZOS and AP guarantee a minimum tolerance.

I think there are hundreds, if not thousands, of practical user "test" reports from satisfied Takahashi users worldwide. To me, they are far more valuable than technical reports that many (including me) don't understand, and what you see when you look through the scope is far more convincing than a piece of paper with obscure figures, often argued over as being subjective or slanted to a particular audience.

It may well work differently for imaging, but for visual use (the use to which most doublets are put), you can't beat the acid test of MK1 eyeballs! 👍

Dave

 

Edited by F15Rules
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4 minutes ago, F15Rules said:

I think there are hundreds, if not thousands, of practical user "test" reports from satisfied Takahashi users worldwide. To me, they are far more valuable than technical reports that many (including me) don't understand, and what you see when you look through the scope is far more convincing than a piece of paper with obscure figures, often argued over as being subjective or slanted to a particular audience.

You trust Takahashi's QA process and they do deliver, fair enough.
But why do other vendors such as LZOS and AP provide minimum tolerances or in some cases let you choose which lens you are getting from a small selection?

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7 minutes ago, Deadlake said:

You trust Takahashi's QA process and they do deliver, fair enough.
But why do other vendors such as LZOS and AP provide minimum tolerances or in some cases let you choose which lens you are getting from a small selection?

Somehow, I wrongly presumed all scope makers rather than general mass producers provided test certification.
Heck at that level of investment, I would feel I need a but more than trust in a QA process.

Nice click bait by the way....

Edited by Alan White
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4 minutes ago, Deadlake said:

You trust Takahashi's QA process and they do deliver, fair enough.
But why do other vendors such as LZOS and AP provide minimum tolerances or in some cases let you choose which lens you are getting from a small selection?

You'd have to get a definitive answer to that question direct from the manufacturer. 

But in the case of AP, if you are making potential customers join a 10 year plus waiting list to get one of their products, maybe you have to try to convince them that they are getting something extra for waiting that long?

Dave

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I would likely buy something like a Tak FC130 f8 if it was available. The benefits of a fluorite doublet in terms of weight, cool down, contrast and transmission. £3.5K to £4K wouldn’t seem unreasonable for such a top end scope, provided it had a decent focuser, preferably FT.

I never felt hard done by through not having a test report for my FC100DC, its optics have always spoken for themselves. I don’t believe Zambuto or Nichol for example give test certificates, they have a reputation to uphold and their kit satisfies their customers.

 

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16 minutes ago, Stu said:

I don’t believe Zambuto or Nichol for example give test certificates, they have a reputation to uphold and their kit satisfies their customers.

👍

Or Lockwood.

I dont think any would be in business long if they were merely avg optics and duds IMHO.

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The LZOS optical tests are to satisfy APM that the objectives have matched the required spec. Not aimed at the scope buyers particularly as far as I'm aware.

How do we know what Tak are planning for the future ?. The FC100-DL came as a surprise to most I seem to recall. 

 

 

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1 hour ago, Deadlake said:

How much was the FS128 when it was out, relative to a 100mm Takahashi? I suspect at 130 mm the TOA is popular as one of the best imagining scopes at that aperture and that's where the market is.

Note:


Takahashi should supply a lens report, LZOS and AP guarantee a minimum tolerance. 
TecnoStar also provides a minimum lens quality on their 130 mm model as well.

LZOS provide test reports because they're a contractor selling components to a third party. They're not doing it for the benefit of the end user even if the people buying the completed scopes do love those Strehl numbers.

Even publicising the minimum tolerance isn't straightforward. Is it referring to peak monochromatic Strehl or minimum across the entire visual spectrum and how much difference would it make in the real world anyway? Ultimately a good test report is worth nothing if you don't like the view through the scope and I don't need a test report to tell me whether I can see false colour or if my scope delivers a perfect star test.

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6 minutes ago, vlaiv said:

I bet that's a really impressive planetary scope and a good 6" F8 mirror is easy to make and apparently should give decent performance even if it's left with a spherical figure.

Mind you, you couldn't pay me to own a Newtonian, they're just not my cup of tea.

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6 minutes ago, Andrew_B said:

apparently should give decent performance even if it's left with a spherical figure.

I think the f ratio should be over f12 for this at 6" aperture? But yes, the likelyhood of getting good 6" f8's and 8" f6's is really high. I guess thats why the 6", long fl newts are called "APO" killers.

Edited by jetstream
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3 minutes ago, Andrew_B said:

I bet that's a really impressive planetary scope and a good 6" F8 mirror is easy to make and apparently should give decent performance even if it's left with a spherical figure.

Mind you, you couldn't pay me to own a Newtonian, they're just not my cup of tea.

Don't mind me, I was being somewhat provocative with that post :D (trying to be half provocative and half funny).

But there is a point to it - maybe not that exact SW model - as you yourself pointed out - people do like nice Strehl figure, but comparing two different aperture scopes with different Strehl is another matter.

On purely optical side of things - larger aperture diffraction limited and obstructed scope can outperform smaller clear aperture with perfect figure. In practice it will also depend on atmosphere of course and target, and observing conditions, and there are also personal preferences of course.

 

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7 minutes ago, jetstream said:

I think the f ratio should be over f12 for this at 6" aperture? But yes, the likelyhood of getting good 6" f8's and 8" f6's is really high. I guess thats why the 6", long fl newts are called "APO" killers.

I think I must have read that info somewhere on telescope-optics.net and this page has the formula for the minimum focal ratio at which a spherical mirror gives acceptable performance as the cube root of 90.15 multiplied by the diameter in inches. For a 6" mirror this would be F8.15 so a spherical F8 optic should be close enough to be good but I'd imagine they'd parabolise it anyway.

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8 minutes ago, vlaiv said:

Don't mind me, I was being somewhat provocative with that post :D (trying to be half provocative and half funny).

Keep working on that vlaiv 😉🤣.

I’m actually almost dreading putting my LZOS 130mm up against the Heritage 150p! 🤪🤪. Hopefully I will get round to selling it before I get the chance 🤣

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26 minutes ago, John said:

How do we know what Tak are planning for the future ?. The FC100-DL came as a surprise to most I seem to recall.

Yep, who knows indeed. I do wish they would stop the obsession with so many 100mm variants and do something else. Mind you, I’m sure the DC, DF, DL and DZ have been commercially very successful for them which is great.

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1 hour ago, F15Rules said:

..so that you're not tempted to sell your FS128 David??😈😂

But joking apart, could such a doublet really be noticeably better than the FS128?🤔

I know mine isn't going anywhere, for any other scope!🤗😊

Dave

I MAY be tempted if an “FC130DZ” weighed around 6.5kgs with tube rings and finder.

That, to me, would be better than the FS128 😁

But as @Highburymark says it may not be commercially viable anyway - but who knows what may happen in the land of the rising Sun ?

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