godra

Dave,it is IM mak-newt in guestion(MN66). Much heavier( around 10kg with accesories) and more length then MK67 which is great scope too but with lesser mount requirements.

Vlaiv,DirkSteele thanks for suggestions. My IM MN66 is primarily planetary scope and can give very high magnifications( 250x-350x),seeing permiting. So I definitivly need AZ mount with tracking( with or without Goto). My budget is around 1000€. 

Hi

I do have IM MN66,fantastic scope in every way...little bit heavy but I don't mind. Only problem is that I have only GM8 mount and possition of focuser is very frustrating when you use it on german mount. What is your suggestions for some mount alternative....I have some AltAz mounts( with tracking) in mind but I would like to hear your thoughts). I am visual only....

Thank you

Many,many thanks to Spile,Doublevodka,Clarkey,Mark and others who suggested to rotate spider vanes by 180deg!! Guys,you are great!!

With the "little" help of my friend I finally managed to do it! Tho whole secondary cage is now moved around 5mm toward primary mirror. Doing so,it was easy than to center secondary under focuser(and complete a collimation). Also,we cleaned the secondary mirror.

Unfortunately I haven't had a chance yet (due to bad weather) to check the collimation on stars.

Before modification:

After:

A few more pictures during the operation:

42 minutes ago, doublevodka said:

Looking at the pictures I suspect rotating the vanes 180 degrees is going to be the fix

If I was a betting man I'd say someone has previously removed the vanes and secondary and reinstalled them the other way round, the two screws seem slightly off to one side but that may just be my eyes...

Maybe worth slackening off the screws slightly and see if you can move it all towards the end of the tube? Sometimes with these things there is a little play which may be just enough

I really, really need to own one of these one day too, there's definitely something about that over engineered look that I like

 

Stupid question left till last, have you tried collimating and star testing as is? With no TAL2 owners jumping in so far, maybe it is by design...

Yes, beautifull scope despite old fashion,industrial look🙂 Build like a tank!

Acctualy,I went trough all phases of collimation and star testing. Stars don't snap to focus and they are pretty blury.

What I found while doing star testing is that on outside side of focus, stars showing images like on those when pinched optics is present.

Something like this:  I attributed it to bad collimation though...

Inside side of focus looks much better-nice concentric diffraction rings but atmospheric condition were not so good for definitive conclusions.

Spile,Clarkey thanks for the suggestions! Yes,it is technicaly possibble to rotate spider vanes and maybe this could help! I also have an idea to move focuser base(whole focuser) few millimeters to the right but that involves drilling wider holes (under focuser) on OTA.  

Here's the pictures of vane assembly and secondary holder. As you can see...nearly no space between two holders,just top of the adjusters can be barely seen.

:

1 hour ago, Pixies said:

Can you confirm that the secondary holder is able to be pulled right back on to the 'vane assembly' (not sure what this is actually called). If it really is as far as it can go, something is definitely wrong.

Any pictures?

Yes,I can confirm that. 

I will post pictures later this day!

9 hours ago, Pixies said:

To bring the secondary away from the primary, loosen the 3 adjusters and tighten the central screw. This will pull the secondary back towards the vane assembly. When you hit the adjusters, back them off a bit more and tighten the central screw again. Keep going until the secondary is under the focuser. However, from my understanding of @godra's first post, this is what he is doing, but the secondary hits a limit before it is correctly under the focuser.

Pixies,that's right.

9 hours ago, Pixies said:

I would be suspicious that the adjusters aren't fully backed-out or the spring is misplaced and stopping the secondary from being fully pulled back.

Nope....I even completely unscrewed adjusters to make sure they didn't block the secondary from fully retracting.

16 hours ago, Spile said:

To move the secondary away from the primary (to the left) you would need to tighten the outer bolts and therefore loosen the centre screw so I do not understand what you mean by  "screwed on"?

Once the secondary is axially centred  I would correct the tilt/rotation error to make the primary mirror reflection circular.

 

I can't bring the secondary holder more left (away from primary mirror) because it is maximum left position when I untighten tree outer bolts and when I fully screw central screw.  In opposite,when I untighten tree bolts and unscrew central screw,then secondary is moving toward primary mirror (to the right on picture)

Dear astro friends,
I recently bought a TAL-2 Newton reflector telescope and tried to collimate it because it has not been used for over 20 years. I noticed that the secondary mirror could not come to the correct position, just below the focuser. See the picture ... When the secondary mirror is moved to the maximum to the left, it still needs to be moved a little more to be exactly in the middle below the focuser. In this position, the central screw is fully screwed on and can no longer be moved backwards ... Other components such as the secondary carrier (spider) or the focuser cannot be moved but are fixed. I wonder if any of you have had similar experiences with this telescope and how this can be solved?
Thanks in advance for the help,

This morning I tried to separate these two parts on my FC100DC but I failed. To much resistance...even with help of my friend. It seems to me that these two elements are also glued to each other !?Has anyone else had similar problems?

With 2.6x GPC I can reach focus, but with 1.6x GPC don't have much in focus...

Two nights ago I made stupid mistake  while I was using my brand new BBHS mirror diagonal with my binoviewer . Nose of the binoviewer is long,especially with GPC. When I came home I saw sometning like dirt on edge of the mirror,but ...that was scratch😪😪 It is located abot 3mm from edge of mirror plate and the size is about 3mm by 2mm( I think).

Now,what to do?  How much this affects image quality?? Weather forecast is very bad for the next 7-10 days...

I made some pictures.

This is view from telescope side:

:

Eyepiece side:

On 27/01/2021 at 19:13, jock1958 said:

Contacted @FLO today and they’re in discussions and if all goes well they will add these products to their website.
I’d like to think there would be a substantial saving over the MEF-3 even after shipping & import costs but will have to wait and see?
Also the quality looks good and should fit a good proportion of the Takahashi range of scopes.

https://astrohutech.store/product/more-blue-precision-focuser-kit-for-takahashi-telescopes/

Now available!!!

https://www.firstlightoptics.com/takahashi-other-accessories/more-blue-precision-focuser-retrofit-kit-for-takahashi-telescopes.html

On 27.1.2021. at 18:51, Highburymark said:

One option if you go for the T2 diagonal is to use just T2 spacers to reach focus. As you see in the attached photo I removed the green Tak spacer element between the OTA and the focuser (it just unscrews) and now can reach focus with binoviewer and all ep combinations, Quark, or in normal night mode with single 1.25” or 2” eps - all I do is change the number of T2 spacers.

Thank you!

I can see your diagonal is one of the Baader T2.  And also I can see that there's no clear consensus is the prism better than BBHS for this F number(7.4) Which one you prefer better?

HI!

Can I reach focus with most 1.25" eyepieces if i buy Baader T2 BBHS diagonal? I have FC100DC with all adapters except n›16 - TKP20001(for staight through viewing)