Piero

After searching for a suitable dovetail in the last two evenings and a interesting conversation about this subject with Mike ( @mikeDnight - Thanks again! ), I found this nice dovetail matching exactly the 95mm Tak Cradle (TKA21420) that I bought: https://www.astromarket.org/takahashi-5/tube-rings---dovetails-5/vixen-style-dovetail-for-tak-fsq85---fsq106---fs60 There are 5x35mm spaces, plus 12.5mm at each borders for a total length of 200mm. I also like the fact that this bar doesn't have an `elongated hole`. Now it's time to deal with the next step... mount head!

Thanks everybody for the very useful and detailed replies! It would have been rather difficult to make the best choice without your feedback!

Tak FC-100DF (tube) + Tak clamshell 95mm ordered!! Ian King was really helpful.

I will get it from Ian King. As I understand the `package` version also includes clamshell, finder, finder bracket. I am not interested in the finder and finder bracket, so if this is the only difference, I was thinking to get the `basic` version and add the clamshell separately.

Thanks John! I will place the order tonight or tomorrow.

Could someone let me know whether this is the correct clamshell / cradle for the FC-100DF, please? Is the one you got? https://www.takahashiuk.co.uk/Adaptors/52-/Takahashi-TKA21420-Tube-Cradle-for-FSQ85 Thanks a lot!!

In my 8" dob I have a 2-speed moonlight. I do like the microfocuser, but I could also easily live without (still nice to have it of course! ). Have to try the regular one at f7.4 before deciding.

Both of them look very well engineered! Do you use the microfocuser with your Vixen 102? (F6.5 right?)

No problem John. I think it is more likely that my English wasn't sufficiently clear! Dual speed can be added if needed. Tak sells the Tak MEF-3 microfocuser. I've read many positive comments about it. It seems it can be easily adjusted if needed.

Actually, my question was related to the focuser, not the optics! I was interested in knowing whether/when replacing the standard focuser with a FT has advantages. After reading the several replies in this thread, I think installing a FT focuser has some advantages, but not really for me. can we get better in terms of optics for a life-time scope? My eyepieces already show me things in a way that I like. What my TV60 misses (not its fault, it wasn't invented for this!) is focal length, aperture, and a better focuser. 100mm makes a great grab 'n' go, but still powerful for studying bright objects. I never felt I wanted a better 60mm than my TV60, and I really doubt I will want a better 100mm than this Tak (assuming that it works properly of course!). My main aim is to have the possibility to study targets at the eyepiece. This 100mm, whether Tak, TV, TMB, SW, will not do everything. So, it will not be "perfect". What matters to me is that it will allow me to study the brightest planets and the very brightest DSOs, without too much cooling time and transport weight. At f7.4 it will show less lateral chromatic aberration than my TV60, while still showing 2deg fov with the 24 Pan, and more than 3deg with the ES30. It's all what I need from a light but serious small telescope.

That was exactly my thought. The counterweight should guarantee more equilibrium for the whole system, which is (I'd say) necessary when using light tripods.

It looks lovely Mark! How is tracking at high mags with the mini-Ercole? Do you need a counterweight?

Those are beautiful! Great scopes guys! @Highburymark Hi Mark, not sure but are you using a mini-Ercole mount and Gitzo tripod? may I ask you your thought about it, please? p.s. it looks very nice and sturdy.

stunning! I like the focuser design!

No problem John! Any feedback is always welcome. I thought that DL focuser were the same as the DF (and the Sky 90), not the DC. I might be wrong though. Does it accept 2" eps directly or you need extra adapters? As far as I understand, the DF comes with a 70mm extension tube, but this is meant for imaging / straight view. (ref. https://www.cloudynights.com/topic/535739-takahashi-fc-100-dc-basic-questions/#entry7195864 )

Okay, that could be the case. On my TV60, eyepieces require about 2cm extra back focus when I observe trees 50-200mt away. If the zoom requires an extra cm to reach focus in daytime, I'd suspect that it might still work in nighttime (with the focuser tube almost all the way out).

Thinking more about, did you check this in day time or extract it from observation notes? I'm asking this because my eyepieces require more back focus in daytime because targets are closer.

Thanks for the info! Well, the good thing is that it can be solved! Your 47mm Baader extension is very interesting. I have a spare Baader 1.25" nosepiece and 2"/T2-to-1.25" adaptor which can be used as mini-extension tube if needed as a temporary solution.

Thank you Olly. Do you know where how much a cradle (95mm) weighs? I am looking for this info on the internet but so far no success..

That'd be fantastic! Thanks again! As far as I understand, the required light path for a given eyepiece to reach focus is independent of 2" and 1.25" diagonals or straight view. The light path in a 2" diagonal is longer than the path in a 1.25" diagonal. So the 2" diagonal will require more inward focus travel (inward difference = 2" diag light path - 1.25" diag light path).

Thank you! You provided me with great information! The TV Nagler zoom, 1.25" TV plossls (8-32), and 24 Pan are nearly parfocal. They all belong to the group B (http://www.televue.com/engine/TV3b_page.asp?return=Advice&id=81). I will use the 1.25" TV everbrite diagonal in the short term. The 24 Pan on this should come to focus without extension tubes then.

@Stu Thank you a lot! Out of curiosity, do you need to minimise the length for travel because of binoviewer and Baader Solar wedge?

@mikeDnight Thanks a lot Mike! really useful information. I will keep this in mind for the future. @jabeoo1 Thank you very much for your help! If this doesn't take too much time, would it be possible for you to measure the travel distance to reach focus with a 1.25" diagonal and a 24 Panoptic (or any other 1.25" TV eyepiece - I can then calculate for the 24Pan using the TV website), please?

Thanks for sharing your opinion on this. That's my concern too. As far as I understand the DC has approx 25-30mm travel, whereas the DF has 68.6mm (2.7"). The Zeiss zoom is the eyepiece of my set that require more inward focus when used in 1.25" mode. It still reaches focus in my TV60 though. The 1.25" eyepiece requiring more outward travel in my 1.25" set is the 24 Pan. Does anyone know if the 24 Pan reaches focus with the DC using a 1.25" diagonal?

Thanks @Stu and @paulastro ! Very helpful comments!