Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

1988 Tak FC-100 - Explore & Restore

Classic Collimation Equipment Optics Refractor
  • Please log in to reply
89 replies to this topic

#1 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 18 May 2021 - 12:38 PM

I bought Ko Ko's 1988 Takahashi FC-100:

 

Tak FC-100 Delivery P06 - OTA (Assembled RS).jpg

 

... and, the clouds rolled in ...

 

Excellent packing & super fast shipping from Singapore to The Swamp.

 

Since the scope is in good condition, this is more of an Explore than Restore thread, but here we go:

 

Tak FC-100 Restore S02 - Bare OTA (Disassembled).jpg

 

Pristine optics in both the APO and the 50mm finder, but here's a before / after cleaning:

 

Tak FC-100 Restore S03 - Lens (BEFORE Cleaning).jpg Tak FC-100 Restore S07 - Lens (AFTER Cleaning).jpg

 

I tried to make some pix of its Newton Rings, but I'll have to try some post-processing to get those to show.

 

As pictured, here's some Info...

 

- Scope Length = 31"

- Tube Diameter = 112.8mm

- Scope Weight = 10.3 lbs


Edited by Bomber Bob, 18 May 2021 - 03:15 PM.

  • plyscope, rerun, Nippon and 12 others like this

#2 Terra Nova

Terra Nova

    ISS

  • *****
  • Posts: 24,781
  • Joined: 29 May 2012
  • Loc: 39.07°N, 229m AMSL, USA

Posted 18 May 2021 - 01:53 PM

That’s a lovely scope. Congratulations. Did you get the clamshell for it or are you going to use rings?


  • Bomber Bob likes this

#3 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 18 May 2021 - 02:12 PM

Got rings on order.  Actually... the rings from my Dakin 4 fit it, too.  Gonna make some pix of it on the Mizar SP here in a bit.

 

I guess the Cloudy Nights are okay for now...  I'm gonna:

 

- DPAC the lens

- Collimate the scope

- Align the 50mm finder


  • Terra Nova and Bowlerhat like this

#4 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 18 May 2021 - 03:16 PM

1st Set Up - Mizar SP:

 

Tak FC-100 Delivery S21 - 1st Setup (Mizar SP RS).jpg Tak FC-100 Delivery S22 - 1st Setup (Mizar SP LS).jpg

 

Both axes balanced.  The Mizar c/w is at the very end of the shaft.


  • Jacques, rerun, mdowns and 8 others like this

#5 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 18 May 2021 - 04:48 PM

DPAC - Green Light:

 

Inside Focus / Outside Focus:

 

Tak FC-100 DPAC P02 (IF) PT4.jpg Tak FC-100 DPAC P03 (OF) PT4.jpg

 

At Focus / AF - False Color:

 

Tak FC-100 DPAC P04 (AF) PT4.jpg Tak FC-100 DPAC P04 (AF) PZ6.jpg

 

DPAC Focal Length = 812mm [+/- 5mm]

 

First time I've seen this pattern AF -- almost like the brightness falls off to one side!

 

I have seen the 3D Center Bowing Towards you effect before - the AT102ED F7, IIRC...  Doesn't show OF.  Overall, this FC-100 lens is not like the FC-50.


Edited by Bomber Bob, 18 May 2021 - 04:55 PM.

  • GreyDay and davidc135 like this

#6 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 19 May 2021 - 06:16 AM

Unlike my 1984 FC-50, I've found no evidence of repainting.  And, this original paint job looks thicker & better applied.  So at least in this case, the FC-100's serial number (8109) does point to the 109th made in 1988...

 

Overall construction is typical TAK, which you either love or hate -- heavy traditional castings, all-metal construction.  I like TAK durability, and the "little touches" like the microscopic grub screws on the outer collars of the lens cell & focuser that lock these in place -- no slipping, slopping, loosie-goosy fit & finish.  That "never go light!" design applies to the 50mm finder & bracket, too.

 

I'm not crazy about the color, but since this FC (like my first FC) will spend 90% of its time in a waterproof case, that's not a big deal.  I came too close to buying an older gray one with serious optical issues; but for once, sanity won out...

 

Some folks buy a new FeatherTouch as soon as they order a top-tier APO.  Not Ole BB.  I only do that after adjusting the focuser myself, and finding the results unsatisfactory.  In fact, with EVERY scope that I've bought for serious observing, I've taken the time to set the focuser to my tastes -- and if that isn't possible, only then have I replaced it -- as with my Meade 826 & its new Lumicon Helical model.  As delivered, the 100's movements are very very smooth, but I'll increase the friction a bit, because I will be using 2" & heavy 1.25" accessories like my binoviewer.


Edited by Bomber Bob, 19 May 2021 - 06:18 AM.

  • Kasmos, Defenderslideguitar, Esso2112 and 1 other like this

#7 bergkamp_

bergkamp_

    Lift Off

  • -----
  • Posts: 7
  • Joined: 21 Jan 2008
  • Loc: Singapore

Posted 19 May 2021 - 11:05 AM

So you are the one who got Koko FC 100.. rare scope.. nonoonn it left singapore.

Edited by bergkamp_, 19 May 2021 - 11:05 AM.

  • Bomber Bob and Defenderslideguitar like this

#8 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 19 May 2021 - 12:53 PM

Yep, lil' Ole BB.  I thought for sure he'd sell it before I made up my mind -- got the PMs to prove it.

 

Some more Notes on this 33 year old Tak...

 

Baffling:  Wow!  3 baffles in the tube, and at least a half-dozen in the focuser assembly, each one about 6-8mm apart.  It's DARK in there, even under an LED spotlight.  Interior paint is flat black, and there are no bright bits to cover.  No need to flock -- I'm not used to that.

 

50mm Finder & Bracket:  Big BONUS with this one.  It's a fine small achro on its own.  And, it has the slot for an Illuminator.  I may add one.  No dust cap, but I think I have one in the shed (where else?) that'll fit.  If the straight-through proves too much for my neck, I'll replace it with a good quality R/A model -- like the Nihon-Seiko that I added to my RV-6.

 

Tak Dust Caps:  Man!  The cast aluminum "trash can" cap for the lens is heavy!  It has that threaded center stop-down aperture with The Logo on it.  The accessory adapter has a thread-on plastic cap, also with The Logo.  (Reminds me of my 1st Classic, Monolux 4380, that had MONOLUX JAPAN stickers on everything, including the tripod clamps!)

 

Push-Pull Lens Cell:  Same as my FC-50.  After the DPAC, I used 2 lasers to nail collimation with a paper mask & center dot.  (The lens makes a nice "clunk" sound.)  I see no evidence that this lens has ever been out of its cell.  No "growths" or traces of alien lifeforms on or between the elements.  I haven't put the lens under my microscope, but I don't see any dust between the elements, either.

 

Cosmetics:  The Finder has the worst scratches.  3 long skinny lines in the paint, like it got shoved through the bracket, and the front screws dug in.  Small scratches on the OTA, EXCEPT on the underside, where it looks like the tube slid in the OTA ring(s).  No dings or dents anywhere.  I doubt that I'll ever hand this one over to JD for a powder-coat...

 

Left to Buy:  Parallax Tube Rings are headed to The Swamp.  Baader rings & things to use 2" accessories.  Water-tight & thickly-padded Rugged Case (like my FC-50).


  • Terra Nova and Defenderslideguitar like this

#9 Kasmos

Kasmos

    Soyuz

  • *****
  • Posts: 3,733
  • Joined: 19 Aug 2015
  • Loc: So Cal

Posted 19 May 2021 - 01:19 PM

I have a friend that has the same model. Yes, the old grey ones are cool but IMO the greenish ones are also very appealing. I like their overall construction and being a stuborn purist, would never change the focuser. The biggest problem that you might encounter, some other scopes may fall into non use.


  • Terra Nova, Bomber Bob, GreyDay and 1 other like this

#10 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 19 May 2021 - 03:35 PM

Yeah...  I had to reassure the Dakin - twice! - The New Kid is just borrowing your rings, 'kay?  That's all - Honest!  

 

The biggest problem that you might encounter, some other scopes may fall into non use.

 

I think it'll be like my FC-50:  There are still times & views where I prefer a quality achro of similar aperture.  While I had the Swift 838, it was my Solar Scope.  Now the Jaegers has that niche.

 

In theory, the FC-100 should trounce my Dakin 4 and C102 on almost all object types.  However, if the Tak won't accept 2" accessories; or, does accepts them, but vignettes more than the Dakin... all bets are off.  Will the F8 Tak's widest fields be as flat as my F10 achros?  The Dakin puts RED in the GRS... will the Tak be "muted" in comparison?

 

Yeah, I'm really looking forward to the Side-By-Sides.


Edited by Bomber Bob, 19 May 2021 - 03:49 PM.

  • Kasmos likes this

#11 Esso2112

Esso2112

    Apollo

  • *****
  • Posts: 1,255
  • Joined: 21 Apr 2017
  • Loc: Magnolia, TX

Posted 19 May 2021 - 03:47 PM

Congrats. It’s a beauty. The 7x50 finder is one of the best out there and they should be for their price.

Bonus is you can use the manhole cover as weapon against this swamp creatures.
  • Bomber Bob likes this

#12 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 19 May 2021 - 06:47 PM

As some of you know, one thing I don't like about Takahashi:  The ludicrous number + expense of unbranded machined rings required to adapt Tak focusers to international standards...

 

(Situation seems similar to that of Mercedes Owners:  If you can afford that E or S Class sedan, you can afford the $600 oil change - so stop your whining!)

 

Case In Point:  The female M55.9x.075 coupling on the focuser.  To get to standard 2" accessories, looks like at least 3 separate ringy thingies need to be stacked...  Yeah, that's secure & stable.  (There may be a single machined aluminum 2" collar that threads directly to the Tak, but I haven't found it yet.)

 

And to show these Tak rings aren't special:  My cheap binoviewer came with 2 thread-in extender tubes - both are shorter than the same part on the FC-100.  Both are black anodized, with the same interior rifling, same knurled edge, same... everything.  And, both thread smoothly into the Tak, and the 2 additional authentic Tak rings that step-down to 1.25" thread smoothly into each of these China-made tubes...



#13 Bowlerhat

Bowlerhat

    Apollo

  • *****
  • Posts: 1,363
  • Joined: 05 Jun 2019
  • Loc: Melbourne, Australia

Posted 19 May 2021 - 09:25 PM

So this is finally your answer to that long thread..congratulations!

Baader planetarium has a lot of adaptors for taks threads. I used one in my FC60 and the black finish blends well. 


  • Bomber Bob likes this

#14 Defenderslideguitar

Defenderslideguitar

    Gemini

  • *****
  • Posts: 3,227
  • Joined: 05 Oct 2016
  • Loc: Connecticut

Posted 19 May 2021 - 09:38 PM

Hope you grow fond of yours   congrats

love my Tak FC-100  circa 1990.........

the focuser is fine  but unlike the focuser on the c -102fl which I changed over to a Moonlight and that greatly improved that scope    my Tak focuser in just fine      if a better focuser pops up i'd be interested i guess 

 i did get the 7x50 finder when one popped up here from Tom D        great  finder

  my fc-100 came with the original  box...

Attached Thumbnails

  • Tac fc-100FullSizeRender (39).jpg
  • Tac fc-100FullSizeRender (38).jpg
  • Takfc-100standingtallFullSizeRender (43).jpg

Edited by Defenderslideguitar, 19 May 2021 - 09:43 PM.

  • mdowns, Terra Nova, Bomber Bob and 6 others like this

#15 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 20 May 2021 - 06:55 AM

So this is finally your answer to that long thread..congratulations!

Baader planetarium has a lot of adaptors for taks threads. I used one in my FC60 and the black finish blends well. 

Yeah... less than an hour after my Gripe Post, I found a reasonably-priced single-piece Baader Click-Stop that threads directly to the FC-100...  but, I stand by my gripes -- especially if you buy Tak-branded stuff...

 

First Star Test

 

Last night.  7/10 seeing - at best.  Perfect star tests on Pollux, Regulus, & Arcturus.  The Moon... in terms younger folks can understand, is like going from EDTV to HDTV:  Everything is sharper, clearer, & more distinct -- and increasing magnification doesn't break down into individual pixels, even at 400x.  But even before the clouds rolled in, seeing limited me to 200x (Radian 4) for most views.  The Moon isn't the best object for assessing optical quality, but if the seeing is better tonight, I'll put the FC-100 up against my Dakin 4" F10.  The phase should be about right for exploring the Alpine Valley, and I have charts for it with feature sizes.


  • ltha, davidc135 and Defenderslideguitar like this

#16 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 20 May 2021 - 10:52 AM

False Color?  What's that??

 

I really tried to get the FC-100 to show false color, but it would not cooperate...

 

Closest that I got was with the Nagler 5 (160x), where a few of the tallest & brightest peaks / crater rims showed a bit of blur + a light yellowish tinge.  I don't call that CA / false color.  It's a defect / artifact made by the accessory.  It also wasn't a function of magnification, as it didn't show with the Radian 4 @ 200x.  

 

I also tested my restored Meade 390 last night.  CA?  Yes, but not annoying or obtrusive; BUT, present in every eyepiece to varying degrees in this 90mm F11 achromatic.  

 

I kinda expected to see maybe a bit in the 100, as it's twice the aperture of my CA-free FC-50, and capable of even higher magnifications.  Nope.  Not with the Moon.  Mars / Jupiter / Saturn?  We'll see.  Venus?  Likely - at least a bit of blue - based on owner reports.  


  • Terra Nova and mikeDnight like this

#17 Terra Nova

Terra Nova

    ISS

  • *****
  • Posts: 24,781
  • Joined: 29 May 2012
  • Loc: 39.07°N, 229m AMSL, USA

Posted 20 May 2021 - 01:06 PM

Tak Dust Caps:  Man!  The cast aluminum "trash can" cap for the lens is heavy!  It has that threaded center stop-down aperture with The Logo on it.  The accessory adapter has a thread-on plastic cap, also with The Logo.  (Reminds me of my 1st Classic, Monolux 4380, that had MONOLUX JAPAN stickers on everything, including the tripod clamps!)

 

We Tak owners refer to them as Manhole Covers for a reason!


  • starmason, Defenderslideguitar and Esso2112 like this

#18 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 20 May 2021 - 03:41 PM

Good Grief!  Got my 1st Pfizer Shot early this morning... I'm fuzzier than usual.

 

There won't be a Dakin vs. Tak until the rings come in -- the Tak is using the Dakin's.

 

If I do go out tonight, it'll be FC vs. FC / 50mm vs. 100mm...


  • Terra Nova and Defenderslideguitar like this

#19 Nippon

Nippon

    Skylab

  • *****
  • Posts: 4,236
  • Joined: 22 Oct 2009
  • Loc: Central Florida

Posted 20 May 2021 - 04:21 PM

Nice scope! I'm surprised that the tube diameter is 112.8 I thought they were 114. But that's only 1.2mm smaller so not exactly a huge difference.


  • Bomber Bob likes this

#20 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 20 May 2021 - 04:49 PM

Yeah, I checked / made sure the tube wasn't out of round -- got the same at each end and around the middle.

 

Seems like someone else found some tube differences between the same models of vintage Taks, but I can't be sure about that -- and for once I can blame it on something external.



#21 Nippon

Nippon

    Skylab

  • *****
  • Posts: 4,236
  • Joined: 22 Oct 2009
  • Loc: Central Florida

Posted 20 May 2021 - 05:15 PM

Speaking of out of round it sure can happen. My TV 85 which I used on a side mount alt/az and a CG4 apparently had a tube that was out of round. When used on the alt/az I'd rotate the scope in the clamshell and it would take an extra one and a half turns of the bat handle to snug the tube in the clamshell.


  • Bomber Bob likes this

#22 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 20 May 2021 - 05:25 PM

Hindsight is always 20/20:  Wish I'd held on to my AT102ED F7 long enough to compare with the FC-100.  Instead, I have to rely on my... what's the word?  Oh, yeah -- Memory!

 

One of the first things I noticed last night:  So many shades of gray in the Maria, and none were washed-out / too bright to see the subtle color differences.  I don't recall the ED having such finesse with these features.  And again, the skies were "wet" with high RH (most at the mid-levels).  Can't wait for an 8+ night.

 

Like my APM152ED F8, it appeared to me that the AT controlled visual CA by suppressing all the colors.  First time I see the GRS in the Tak, I'll know if it's like the FC-50, which is aperture-limited on the uber-subtle Jupiter belt colors.  That is, I expect the 100 to lean towards the Dakin's GRS more than the AT's -- but without the CA.

 

Tonight, I hope to compare the 100 with the 50 on star colors.  As I've posted many (too many!) times, star colors in the Tiny Tak are the closest to my nekkid eyes of any of my refractors -- so far -- with the exception of the phenomenal Vixen FL80S.

 

BIF:  I sold the Vixen.  Naturally, in hindsight, I'm thinking about another 3" APO.  Definitely not a rush or high priority.  I missed out on a Mizar FA-80 on ZEN, but I keep checking there.  I'm also interested in testing one of the TS-65/1000 SA Triplets.  It's been YEARS since I haven't had a 60mm longish frac. But I am down-sizing -- can't ya tell??


Edited by Bomber Bob, 20 May 2021 - 05:32 PM.

  • Defenderslideguitar likes this

#23 Defenderslideguitar

Defenderslideguitar

    Gemini

  • *****
  • Posts: 3,227
  • Joined: 05 Oct 2016
  • Loc: Connecticut

Posted 20 May 2021 - 06:35 PM

Tiny Tak are the closest to my nekkid eyes of any of my refractors -- so far -- with the exception of the phenomenal Vixen FL80S.    BIF :  I sold the Vixen.  Naturally, in hindsight, I'm thinking about another 3" APO..

 

 

Yes    I recently sold the venerable Vixen80fl   that was one of my best scopes. If not but for the long desire and search for the older Tak FC-76   I would still have the Vixen 80fl....miss it? you betcha...but   I sold it to a respected member of the classic folks here   and he says it is great and is now his most used scope  so I am happy to have placed it in good hands....

 

now when I start jonesing for the next fluorite    my favorite  "F" word      I'm thinking   what can I get that is a step down from the FC-100  and a step up from the FC-76 I have and the Vixen 80fl I sold?     wait for it..............................


  • Bomber Bob likes this

#24 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 19,535
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 20 May 2021 - 10:05 PM

... the RARE Vixen FL90S comes to mind.

 

FC vs FC

 

I put the FC-100 on the tall pedestal Meade StarFinder EQ, but left the FC-50 on the VersaGo 2...  Why?  Cause the CV-19 shot has added to my senior senility, that's why!  (The Tak SC / Filo was unoccupied, but under a tarp.  Outta sight, outta BB's mind, I guess.)

 

Seeing was much better tonight from 1930L to about 2130L (0030-0230Z) -- most noticeable while the Moon was slightly E & W of the meridian.  But... surface winds were SE at 8-12 knots.  Didn't effect either of these relatively massive Taks.  (Kinda cool to say, my TAKs - plural.)  

 

CA Comparisons

 

Both Taks used Tak prisms.  Started on the Moon at 20x each.  Zero fringing, zero blue, red, green, or yellow seen on the Super Bright disks.  Ditto as I stepped up to 30x per inch, and 50x per inch.  

 

Star Color Comparisons

 

Besides Regulus & Arcturus, there's a RED star between Gemini & Cancer that I really like, so I actually started there after the luna-see.  I saw no color differences at 40x & 80x.  FC-100 Arcturus is like FC-50 Arcturus, which is like what I see myself.  So if there's scope error, it 100% mimics BB error -- can't imagine Tak letting that happen.

 

Magnification & Resolution Comparisons

 

40x / inch & 80x / inch...

 

It's easy to get both FCs to 80x; tough! to get the 50 to 160x -- had to use the .965" ASTRO 2x Barlow.  It's a circa 1964 accessory in mint condition, so that may have affected the 50.  But, it didn't look like it.  For consistency, I did swap the spectros .965" PL5 between the two.  To get the 100 to 80x / inch, I used my brand spanking new (delivered yesterday!) Tak 2x Barlow.

 

Obviously, the 100 showed more fine details than the 50 at both settings.  What I wanted to see was whether one or both got "soft" at the near-extreme magnifications.  Nope.  My primary target was the "shield" around the crater Copernicus.  What's surprising is just how much the Tiny Tak can show in 8 or better seeing.

 

After this, I ignored the 50 for a bit to count Plato craterlets (4), explore the Alpine Valley, and the area around the Rupes Recta (Straight Wall).  Some of the tiny features that were difficult last night were much easier tonight.  (Duh, huh!)  Like... the 2 micro-craters on either side of the crater end of Rima Birt.  


Edited by Bomber Bob, 20 May 2021 - 10:48 PM.

  • Terra Nova, mikeDnight and Defenderslideguitar like this

#25 Terra Nova

Terra Nova

    ISS

  • *****
  • Posts: 24,781
  • Joined: 29 May 2012
  • Loc: 39.07°N, 229m AMSL, USA

Posted 21 May 2021 - 10:18 AM

BIF:  I sold the Vixen.  Naturally, in hindsight, I'm thinking about another 3" APO.  Definitely not a rush or high priority.  I missed out on a Mizar FA-80 on ZEN, but I keep checking there.  I'm also interested in testing one of the TS-65/1000 SA Triplets.  It's been YEARS since I haven't had a 60mm longish frac. But I am down-sizing -- can't ya tell??

Here you go then! The perfect compliment to your FC-100:

 

https://www.cloudyni...c-76-f8-mc-ota/


  • Bomber Bob and Defenderslideguitar like this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics





Also tagged with one or more of these keywords: Classic, Collimation, Equipment, Optics, Refractor



Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics