182 replies to this topic

[Mike Clemens]

Ooo I like that better, now if the lettering could just be the classic blue scheme for TEC FL's !!

[photoracer18]

I believe the optics are done in-house with one of the opticians being Yuri's son.

 

Here is the OTA with dew shield extended.  

 

Many have already commented on the black shield and gold lettering.  Both do stand out to me but don't look bad at all to me when the scope mounted.

 

My only carp is that the black paint is a finger print magnet.  Every time I touch the dew shield to extend or retract it, I leave a finger print.  It's not nearly as glaringly bad as finger prints on a high gloss black surface and they do come off easy enough, but I find that annoying.

 

Maybe with enough badgering (which CN is good at),  Yuri will change the shield just like when people carped about how few baffles there were in the original 140EDs (even though technically the carping had ZERO merit).  Of course the original run of 140 EDs had black shields too.

 

Jeff 

I had #073 and it was a white dewshield.

[dscarpa]

 Carp on mon! It would be nice if  buyers had a choice of trim color  like with WO which I dearly with included black or gray. I'd be ok with either but would go with white. David.  

Edited by dscarpa, 11 April 2019 - 03:28 PM.

[jrbarnett]

I don't think you can compare the two. In fact, I wonder besides the fluorite, what is comparable. 

I am sure the 140fl is awesome, don't get me wrong. 

When TEC set out to design their triplets they studied the APQ design as the starting point or at least as a major "donor" for their design.  Of course TEC started work on its offerings in the early 2000s.  APQs hadn't been produced for more than a decade (and in fact had a very limited production run on account of being uneconomic to make and sell; 1991-1994), and used lens materials custom made in house by the Jena operation, when TEC began its design and development.  The APQ was killed by reunification and the difficulty the formerly state-sponsored/subsidized enterprise had in adapting to free market dynamics in labor, materials supply and sales.

 

TEC adopted the materials du jour in terms of glass types, but from a format perspective (moderately slow oiled triplet w/low dispersion material sandwiched between mates, quality hand figure, quality levels of polish, modern coatings for the era of production, etc.) it's pretty clear they borrowed quite a lot from the earlier Zeiss designs.  In fact, other than TECs I don't think you can get any other refractors today (manufactured new) that have more kinship to the APQ design. 

 

In terms of execution quality, hard to say.  Though APQs are revered and some of them test exceptionally well on the bench, not all test so well.  TECs are similar; generally excellent in execution with an occasional more good-middling effort.  There aren't really enough samples for which test data has been published to figure out where TEC median quality rates relative to APQ median quality.  My hunch is that, freed from the constraints of needing to make a buck, SOE Zeiss probably has the edge in figure quality, though anyone who has ever driven a Trabant might not agree. 

 

Best,

 

Jim

[lwbehney]

Regarding the slightly "warmer" tint that is reported in the fluorite TEC compare to the TEC 140 ED:  I have a Takahashi FS 128 and also noticed the slightly warmer tint to daytime objects, such as leaves on trees when compared to my Celestron 8" with XLT coatings. My thoughts about this is that the fluorite crystal passes red light including infrared with less dispersion than glass and that this may account for the "warm" tint described, i.e. the red light remains in tighter focus close to the infrared better than glass and in the infrared also and for those individuals who can see a little deeper into the infrared than others, they will see the warm tint described by so many in fluorite refractors.  

This may be why that the TEC 140fl design is aiming for the best blue correction, because it already will automatically have an advantage in the red wavelengths. 

I recommend that astro-imagers with fluorite refractors, think about reaching out a bit towards those longer wavelengths.

 

Larry

[Scott99]

Most Tak doublets have slightly "warmer" tone due to the unfocused blue, not the fluorite in the lens.  People buy triplet apos like the 140FL to get that last bit of false color cleaned up.

[Jeff B]

Some interesting ideas concerning the touch of "warmth" both Eric and I saw on solar system stuff (Satrun, Moon and Mars).

 

However, on Vega, at high, power, I saw no real trace of it, in fact, the stellar core was quite white in tint/tone with the 140ED showing a trace of a yellow tint.  There was a very, very minor hint of a red "glow" next to the airy disk at focus at high power in the 140FL, with a very mild purple glow using the 140 ED. 

 

As purple is really a combination of red and blue, maybe the 140FL's better correction in blue and slightly lesser correction in red, relative to the 140ED, left just that tiny bit of residual red to be detected.  This makes sense and seems to line up with what I saw.   But please remember, I was comparing samples of one for each scope and it took very high power to tease out that difference between them. 

 

So, if you all have one or the other (or both?)       

 

But...

 

Anybody want to send me other samples of each?!!  

 

Jeff

[25585]

Somebody in the UK has one, lucky person!  https://stargazerslo...ope-first-look/