Tak FC-100 - a few questions :)

[jock1958]

16 minutes ago, F15Rules said:

You're not missing anything Jock..I bought the same set, it's great value.

The prism has 32mm clear aperture so shouldn't vignette any 1.25 eps.

You can use 2" nosepiece/T2 as well (have done so before), and the prism build is certainly up to the weight of 2" eps - but vignetting is then likely (Although not actually too bad I found).

A great bit of kit?☺.

Dave

Thanks Dave...Phew... thought I might have blundered!  As previously mentioned on this thread you have to remove the 2" (73mm) extension tube to achieve focus for long range work and vice versa for close range work, am I right?

I wonder if a 40mm extension tube would give you that sweet spot where you don't have to remove or add anything?

 

[Timebandit]

1 hour ago, jock1958 said:

.  Do you think I'm missing something? 

 

 

58 minutes ago, F15Rules said:

You're not missing anything Jock..

 

I don't know ?

I couple of ZAO in the optical chain would certainly assist you get the best out of your quality set up ?

 

 

[25585]

1 hour ago, F15Rules said:

You're not missing anything Jock..I bought the same set, it's great value.

The prism has 32mm clear aperture so shouldn't vignette any 1.25 eps.

You can use 2" nosepiece/T2 as well (have done so before), and the prism build is certainly up to the weight of 2" eps - but vignetting is then likely (Although not actually too bad I found).

A great bit of kit?☺.

Dave

Too bad it's really just for 1.25 inch eps. Baader's Amici and Zeiss prism 2 inch diagonals are very expensive indeed.

[Pig]

 I was thinking of getting the 2” but £450 put me off initially, but I may still get one ? as the Astro fund is building up nicely again.

[Piero]

I have the 2" bbhs silver mirror. It cost me £330 from Microglobe. According to William Paolini and others who compared it against the baader Zeiss prism, there s not much in between.

II decided to get a 2" model because I already had some nice 2"eyepieces and filters. Also, my eyes are not equal,, making binoviewing a bit tricky. I think Jock made a wise choice because he got a very good diagonal for the 1.25" eyepiece set he has and at a sensible cost. 32mm aperture will allow him to use some 2" eyepieces if he ever decides to after buying some extra adapter. 

[jock1958]

4 hours ago, Timebandit said:

 

 

I don't know ?

I couple of ZAO in the optical chain would certainly assist you get the best out of your quality set up ?

 

 

Found some interesting info on page 3 of Cloudy Nights about extension tubes and adaptors to get either your 2" or 1.25" EP's into focus

https://www.cloudynights.com/topic/541932-takahashi-fc-100df-steinheil-fluorite-doublet/page-3 

[BGazing]

Well, what can I say, DF is a thing of beauty.More detailed report to follow, I have picked it up but proper testing will hopefully take place once I drive it home.

Got t2 BBHS mirror diagonal with 1,25 clamping on the nose part, but quick test with 4.7 ES eyepiece could not get into focus without 2inch extension being used...that sort of surprised me. Either it is the eyepeice (which I  doubt) or I foolishly thought that T2 is sufficiently comparable in light path to full 2inch BBHS (which appears to have no problems).

[Piero]

2 hours ago, BGazing said:

Well, what can I say, DF is a thing of beauty.More detailed report to follow, I have picked it up but proper testing will hopefully take place once I drive it home.

Got t2 BBHS mirror diagonal with 1,25 clamping on the nose part, but quick test with 4.7 ES eyepiece could not get into focus without 2inch extension being used...that sort of surprised me. Either it is the eyepeice (which I  doubt) or I foolishly thought that T2 is sufficiently comparable in light path to full 2inch BBHS (which appears to have no problems).

Congratulations!  

 

According to the specs on Baader website (https://www.baader-planetarium.com/en/baader-t-2-bbhs-r-mirror-diagonal.html , https://www.baader-planetarium.com/en/baader-2"-bbhs-r-mirror-diagonal-with-2"-clicklock-clamp.html), the light paths for the T2 and 2" BBHS mirror are 43mm and 112mm, respectively. You will need an extension tube to reach focus with the T2 model.

With a clear aperture of 33mm, you might just marginally notice some vignetting with a 20mm Lunt HDC, when the T2 is fitted with a 2" nosepiece. The T2 will also make your life easier if you intend to binoview at some point.

Well done! 

[BGazing]

23 hours ago, Piero said:

Congratulations!  

 

According to the specs on Baader website (https://www.baader-planetarium.com/en/baader-t-2-bbhs-r-mirror-diagonal.html , https://www.baader-planetarium.com/en/baader-2"-bbhs-r-mirror-diagonal-with-2"-clicklock-clamp.html), the light paths for the T2 and 2" BBHS mirror are 43mm and 112mm, respectively. You will need an extension tube to reach focus with the T2 model.

With a clear aperture of 33mm, you might just marginally notice some vignetting with a 20mm Lunt HDC, when the T2 is fitted with a 2" nosepiece. The T2 will also make your life easier if you intend to binoview at some point.

Well done! 

Thanks! If only the sky will clear, even full Moon will do it.

T2 is indeed 43mm, but 1.25 eyepiece clicklock is additional 33mm, I believe, and 2 in nose additional mm or two...altogether around 77. I am short of 35mm, and 100mm Tak extender is too much. Any ideas for a well-baffled 35mm extension? Not sure I can find anything in Baader section.

I can alternatively use Baader clicklock 2in and disregard the nuances in performance.

Edited March 29, 2018 by BGazing

[Piero]

1 hour ago, BGazing said:

Thanks! If only the sky will clear, even full Moon will do it.

T2 is indeed 43mm, but 1.25 eyepiece clicklock is additional 33mm, I believe, and 2 in nose additional mm or two...altogether around 77. I am short of 35mm, and 100mm Tak extender is too much. Any ideas for a well-baffled 35mm extension? Not sure I can find anything in Baader section.

I can alternatively use Baader clicklock 2in and disregard the nuances in performance.

I'd ask FLO, or Baader directly, for suggestions. They reply very quickly. 

A 2" clicklock would also enable you to use 2" eyepieces (up to ~33mm field stop without vignetting).

Edited March 29, 2018 by Piero

[BGazing]

1 hour ago, Piero said:

I'd ask FLO, or Baader directly, for suggestions. They reply very quickly. 

A 2" clicklock would also enable you to use 2" eyepieces (up to ~33mm field stop without vignetting).

I have 2 in and 1.25 adapters on the eyepiece side for t2, did not plan on going wider than 31mm (which is as much field stop as t2 would allow). No biggie, will test it first in various configurations. Cannot wait.

The size is just about the limit of handling a tube comfortably with one hand and mounting it, I guess. 5 inch refractors are a different league...

[25585]

3 hours ago, BGazing said:

I have 2 in and 1.25 adapters on the eyepiece side for t2, did not plan on going wider than 31mm (which is as much field stop as t2 would allow). No biggie, will test it first in various configurations. Cannot wait.

The size is just about the limit of handling a tube comfortably with one hand and mounting it, I guess. 5 inch refractors are a different league...

A tube handle is a good thing. Two hands handling as well. 

[BGazing]

Talk about frustration. Ayo arrived but without the second saddle, it got lost somewhere in the ordering process. But worse is that I realized that the dovetail I have ordered and mounted on the clamp

https://teleskop-austria.at/TKP71423_Takahashi-Prismenschiene-185mm-fur-Vixen-Level#m

is actually too narrow to be gripped properly by the Ayo claim. DSV-M grips it but is puny to handle FC100, and Evo mount grips it but barely. It's 41mm at the widest point, I apparently paid no attention.

@Piero I tried the link for the dovetail you ordered but nothing's there now...anyone has any recommendation?

[Piero]

@BGazing, as by PM, I'll double check whether the one you suggested (  https://www.takahashi.be/takahashi-monteringen/tube-rings---dovetails/vixen-style-dovetail-for-tak-fsq85---fsq106---fs60, ) is like mine. It looks like identical. I also attached two safety bolts at each extremity, just in case the AYO clamp looses. 

 

[Piero]

@BGazing, Here are some photos of my dovetail. 

 

The model was called : Vixen Style Dovetail for Tak FSQ85 / FS!106 / FS60 200mm long , so I think it is exactly the one on the website you sent me. It's a nice dovetail in my opinion. 

I bought the extra two bolts separately. Mine are: M8 x 30mm A2 Stainless Steel Socket Cap Allen Key Head Bolt. As you can see in the third photo, they are taller than the dovetail. I intentionally wanted this because I can hang up to two wrist weights on the two ends of a screw to balance eyepieces, if needed.

Edited March 29, 2018 by Piero

[avtaram]

I bought the same dovetail on Piero's recommendation for my fc-100dc and it fits nicely on the Tak clamshell.

Avtar

[BGazing]

Thanks, guys. I have tried cannibalizing AOK dovetail from my Borg and it works. So there are options, although Tak options really seem to be...weird.

[25585]

For such I recommend Losmandy D clamp and dovetail. They are wider, accommodating the whole Tak clamp base, and are so more stable. 

@Stuwas selling a clamp, might still be. @FLOsell D dovetails https://www.firstlightoptics.com/adm-losmandy-type-d-series/adm-losmandy-style-universal-dovetail-bars.html

Edited March 29, 2018 by 25585

[Piero]

For visual, I don't see the need of a losmandy dovetail to be honest. 

[25585]

36 minutes ago, Piero said:

For visual, I don't see the need of a losmandy dovetail to be honest. 

For added security and stability in mounting an expensive refractor, I do!  Whatever its uses. ?

[Piero]

5 minutes ago, 25585 said:

For added security and stability in mounting an expensive refractor, I do!  Whatever its uses. ?

well..

Security: adding two bolts at each end is completely enough if the clamp looses. 

Stability: on my AYO II, vibration damping is less than 1 second when the legs of my tripod are fully extended, so no really an issue. 

Whatever dovetail you prefer is up to you of course, I don't argue with that. Whether a Vixen or Losmandy dovetail is better for visual use, I'd say that for visual one is better off investing on a solid tripod rather than a Losmandy dovetail. 

[BGazing]

Well, the dovetail sorted itself out thanks to Beat of AOK who is graciously sending it to me for free, as well as a free second clamp which I wanted but he forgot to include in the order and I did not pay. Talk about Easter presents!

It's cloudy here, as expected.

[25585]

12 hours ago, Piero said:

well..

Security: adding two bolts at each end is completely enough if the clamp looses. 

Stability: on my AYO II, vibration damping is less than 1 second when the legs of my tripod are fully extended, so no really an issue. 

Whatever dovetail you prefer is up to you of course, I don't argue with that. Whether a Vixen or Losmandy dovetail is better for visual use, I'd say that for visual one is better off investing on a solid tripod rather than a Losmandy dovetail. 

Its partly because the Tak clamps (2 for my DL) are so sturdy, have larger footprint and are heavier, that I decided on Losmandy D. Vixen width might have put too much strain on a narrower bar and bolts leading to mishaps ?

 Bit of a colour combination, white tube, white mount, pale green clamps and Primaluce clamp + bar. Have to post a photo.... ?

Edited March 30, 2018 by 25585

[Timebandit]

17 minutes ago, 25585 said:

 

 Bit of a colour combination, white tube, white mount, pale green clamps and Primaluce clamp + bar. Have to post a photo.... ?

 

Yes . 

Let's see a picture of this multi coloured Tak. ?

That will get the Tak owners club talking. Its usually any colour you want Sir ,as long as its white and grey ? ?

 

 

[25585]

6 minutes ago, Timebandit said:

 

Yes . 

Let's see a picture of this multi coloured Tak. ?

That will get the Tak owners club talking. Its usually any colour you want Sir ,as long as its white and grey ? ?

 

 

Purists ? Glad go be bucking a trend ?

Strictly black and silver for my Equinoxes though ?