fma38 wrote:

claudevh wrote:

For the  'off-the-shelf' replacement crown, I have seen some interresting "astronomical" stuff's ... I thing mainly to "Bader Planetarium" system to adapt their universal system to the Celestron Nexstar GT mount series who share basically a lot of pieces with the Merlin/Orion (same mother company = Synta), see the next links (all in german):
http://www.baader-planetarium.de/univer … ttform.htm
http://www.baader-planetarium.de/downlo … klemme.pdf

I have no time at the moment to take more informations, but I thing that the "overal" dimensions (mainly the thickness)
of the Baader pieces are more favorable and will permit to win additional "mm" !
Anyway the mounting piece will fit perfectly the Merlin head in replacement of the original one !

This is great! Any idea of the price of such crown?

I think I finally located a price - they seem to have no search facility on their web site,ugh! - you'll find the item about 3/4 of the way down this page:
http://www.baader-planetarium.de/zubeho … rsalklemme

There appear to be two models - one is 74 Euros (approx. GBP 64, US$ 94), the other 85 Euros (approx. GBP 72, US$ 108 ), not sure whether this is including or excluding VAT.

It looks good, but this is more than I would wish to pay, but I/we wouldn't want their dovetail bracket for mounting a telescope anyway.

I was quoted nearly GBP 90 for a one-off crown machined to Thierry's drawings by local engineering company;far more than I was willing to pay.

I think I'd be happy to pay say GBP 25 for a crown made to Thierry's spec., I would consider it at GBP 40, maybe reluctantly purchase at GBP 50 but I really would not want to pay more than that. Perhaps my expectations are unrealistic?

BTW what exactly does the 'red disc' do that has to be transferred from the old crown to the replacement? The German word 'Mitnehmerscheibe' is translated (by Babel Fish) as 'driving disk' but that does not really explain it's function for me. What is it made of? Could you make one if the original got damaged when removing it from the original crown?

Last edited by mediavets (2008-11-14 22:03:45)

Hey Stop !

I have no idea if those pieces are wel adapted to what we want !
I have no idea about the dimensions of the pieces, mainly the tickness who should be much lesser than the original crown otherways we will just win nothing !

The difference between the 2 prices come from the dovetail part

claudevh wrote:

I have no idea if those pieces are wel adapted to what we want ! I have no idea about the dimensions of the pieces

Here is a PDF, which shows the clamp-exchange on NexStar-Mount.
http://www.baader-planetarium.de/downlo … klemme.pdf

I mailed to Baader asking them for the dimensions of the crownplate and if they will sell the crownplate only.
IMO it is more flexible to mount a fixed guide rail on the crown with an adjustable/slideable quick release

pics shows the prototype-rail of my robot, on Merlin the rail can be much smaller

Last edited by Paul (2008-11-15 11:04:04)

fma38 wrote:

Could someone contact them to know if they can sell the crown alone? And to ask them for the exact dimensions...

someone did it

http://www.autopano.net/forum/p32688-to … -48#p32688

Last edited by Paul (2008-11-15 10:25:46)

fma38 wrote:

Ok, I'll try to send them a e-mail...

Hi Frederic, again: I did it already, send them a mail, asking for dimensions and if they will sell it separate ...

Hi all,

Sorry but I thing that the Canon 5 D could be use without modification of the Merlin Head, see post of Trekker 317 hereafter:
http://www.autopano.net/forum/p19302-20 … -51#p19302 and the explanations of the different dimensions hereafter:
http://www.autopano.net/forum/showimage … Etiers.jpg

If necessary, you could modify the Merlin head according the following rules:
1. Orininaly the head without modification allow the usage of all camera's wtih "A measure" of maximum 40 mm
2. A further mm's will be gained by separating the vertical and the horizontal part of the head:
    40 + 10 = 50 mm "A measure" maximum with simple separation according the next post:
    http://www.autopano.net/forum/p32400-20 … -57#p32400
3. Other furter increasements could be realized according the Wiki at the next URL:
    http://www.autopano.fr/wiki/action/view … e_fixation

Frederic, is that possible to adapt this part of the Wiki ?

Many other stuff could be updated like the summaries in English and the traduction in French made by Mediavets

Who can do that and how ?

claudevh wrote:

Hi all,

Sorry but I think that the Canon 5 D could be use without modification of the Merlin Head, see post of Trekker 317 hereafter:
http://www.autopano.net/forum/p19302-20 … -51#p19302 and the explanations of the different dimensions hereafter:
http://www.autopano.net/forum/showimage … Etiers.jpg
cool:

Claude and Frank,
It appears that I am mistaken - the Canon 5D is smaller in that dimension that I had imagined - I should have checked the size of the Canon 5D body before posting. My apologies.

It seems that it is possible to get the Canon 5D (the body at least) very close to the NPP if mounted in portrait orientation without modifying the dovetail-clamp crown. As Frederic pointed out, it will depend to some extent on the diameter of the 'barrel' of the lens you are using as much as the size of the camera body.

I think these pictures of Klaus' setup show a 5D on the Merlin?:
http://www.autopano.net/forum/p30829-20 … -37#p30829

My small D40 body fits fine, using the standard dovetail-clamp, with the standard 18-55mm kit zoom and the Nikkor 10.5mm FE, but it's a very tight fit using the Sigma 8mm f3.5, and any lens with a bigger barrel would be a no-no. And, I can get a +90 degrees zenith shot with the Nikkor 10.5mm FE and Sigma 8mm f3.5 FE on the D40 using the Merlin but this is not possible with many larger/longer body/lens combinations.

You may still need/wish to modify (reduce the size of) the large knob on the camera screw on the standard dovetail bar to maximise vertical rotation.
http://www.autopano.net/forum/p31985-20 … -52#p31985
http://www.autopano.net/forum/p31499-20 … -09#p31499
http://www.autopano.net/forum/p31502-20 … -39#p31502

Last edited by mediavets (2008-11-18 18:06:56)

Paul,

None of those dimensions seems to be a close match for Thierry's drawings of a replacement crown for Merlin:
http://www.autopano.net/forum/postgalle … hierry.jpg

It would be great if their current part had happened to be the correct size for Merlin. But that doesn't matter really. If they are set up to make a rather similar part they could perhaps make one especially for Merlin without too much trouble.

Good luck with your further investigation.

I think we may only need a part like the element they label 'Montageplatt'? But maybe with some more threaded holes it it to enable mounting of a camera-specific 'arm'/rail.
http://www.autopano.net/forum/postgalle … klemme.jpg

Or maybe people would like the dovetail clamp element too?

Last edited by mediavets (2008-11-18 15:04:16)

if that lathe/mill-story of Tom ends up lucky, we will produce adapter plates in three or four weeks

his lathe went back to the seller for repair/fix

If you want to edit the wiki, just create an account, and then edit the pages. This is the 'magic' of wiki

big hello dear Merlin users,

up to now we are serving the needs of astronomers, who frequently need specially designed adapters. We have an attached workshop and can provide economic solutions, hopefully :-)

The merlin is popular among astronomers as an ultraportable motorized mount for small telescopes, as you know we have it in stock. The problems for using it for pano tasks are almost clear to us, we understand what is NPP and have seen the fabulous panos at lookaround.nl - thanks bigwade for all the links!

Still I dont understand the connection between the crown, and the A value which is said to be 40mm for the Merlin. On a camera, it is the distance bottom to lens mount center. But on the Merlin? Is it the distance prism-mount to base rotation center?

We deliver the Merlin with an L-shaped photo adapter, probably you replace it by the Nodal Ninja or a similar device. What role plays the crown?

If somebody could send us a drawing of the needed crown replacement, as simple as possible (every drilling and so on adds to the price...) we are ready calculate the costs.

best regards form Austria, Tommy

Welcome to this forum Tommy.

I just bought a Merlin from you, but when I switch it on the "Guide" button LED goes on, "Set"- and "Go"-button starts blinking.
The Merlin does nothing.

This error is not explained in the manual. Can you help me?

A drawing of a crown replacement you can see here:
http://www.autopano.fr/wiki/action/view … %A9canique


PS: you made a typo in the link to your website, the 's' in austria is missing

Last edited by Paul (2008-11-28 18:40:20)