3 axis rotation mount with goniometric tilt

AndrewC · Post by **AndrewC** » Sat Oct 10, 2009 10:00 am

Personally I don't like threads once they get over 3 or 4 pages so I've started a new one for my creation. Chris' is much more elegant but I can't stretch to a 2 axis goniometer

This is partly to show what a goniometric setup can do.

For the following images imagine your stacking camera is at stage right looking the fly face on in the first picture. Squared paper with arrows is fixed to the base the mounting stage is taped to.

Hardware (starting from the bottom):

1) Goniometer giving tilt, axis of rotation is x (straight in/out of the image) with a centre of rotation 50mm above the base.

2) Rotation base. rotates around z-axis (straight up). They are stacked in this order simply because that is the only way they will physically connect.

3) Bolt threaded through bulkhead with a 0.5mm hole in the end holding mounting pin. Axis of rotation Y - along stacking axis. Thread is 1mm per turn so it lets me adjust the specimen forwards/backwards in 1mm steps.

Zero position:

Tilt down (to look at the top of the head)

Tilt up (to get "face on")

Rotate in Z to look at right cheek

Rotate in Z and Y to look at bottom of head ?

Rotate in Z to look at left cheek

It's not 100% perfect but it beats the pants off my previous methods of bending pins and sliding around on magnets and hunting for the subject with linear adjustments. Some linear correction is needed, unless you luck out and your area of interest is at the xyz axis intersection.

Planapo · Post by **Planapo** » Mon Oct 12, 2009 9:23 am

I get some good ideas from these pictures.
Thanks for posting, Andrew!

--Betty

AndrewC · Post by **AndrewC** » Mon Oct 12, 2009 2:30 pm

Planapo wrote:I get some good ideas from these pictures.
Thanks for posting, Andrew!

--Betty

That's why I posted them

Andrew

dmillard · Post by **dmillard** » Wed Oct 14, 2009 4:49 pm

Thank you Andrew -

These images have inspired me to finally move beyond my current clumsy positioning device (without spending too much money

)

David

g4lab · Post by **g4lab** » Wed Oct 14, 2009 7:04 pm

David my I presume that that was you in the honorable mention or images of distinction section of the Nikon Small World Contest.

If so my congratulations.

Wim van Egmond was also there if I remember correctly.

I hope this isn't old news.

dmillard · Post by **dmillard** » Thu Oct 15, 2009 1:07 am

g4lab wrote:David my I presume that that was you in the honorable mention [ ] of the Nikon Small World Contest.

If so my congratulations.

Thank you!

Chris S. · Post by **Chris S.** » Fri Oct 23, 2009 8:56 pm

Brilliant, Andrew! (Sorry I'm so late I'm commenting, but was suddently and violently beset by work). Yours is an elegant way of getting all the axes at less expense. If I hadn't lucked out and found an inexpensive set of matched goniometers, I'd copy your approach. Doubt I'd have thought of it on my own.

As discussed, my bet is that once more folks discover the joys of a goniometric stage, they'll wonder how they did without it.

Also, on your use of lined graph paper and arrows to illustrate how the specimen remains largely in place while being rotated in various axes--well done!

--Chris

PaulFurman · Post by **PaulFurman** » Sun Oct 25, 2009 11:13 am

Very nice setup. What is the exact model of the rotation stage above the goniometer?

I have a larger goniometer & xyz stage which were originally acquired for a home made tilt/shift view camera. I've rearranged the components into an optical bench with PB4 bellows but it lacks rotation. This is the best item I could find:

40mm rotation stage part number 124-0030 $200.00
http://www.optosigma.com/miva/merchant. ... ion+Stages

Here's my original rig:
http://www.flickr.com/photos/edgehill/2 ... 231101723/
And the new setup:
http://www.flickr.com/photos/edgehill/3 ... 231101723/

AndrewC · Post by **AndrewC** » Sun Oct 25, 2009 12:21 pm

PaulFurman wrote:Very nice setup. What is the exact model of the rotation stage above the goniometer?

I have a larger goniometer & xyz stage which were originally acquired for a home made tilt/shift view camera. I've rearranged the components into an optical bench with PB4 bellows but it lacks rotation. This is the best item I could find:

40mm rotation stage part number 124-0030 $200.00
http://www.optosigma.com/miva/merchant. ... ion+Stages

Here's my original rig:
http://www.flickr.com/photos/edgehill/2 ... 231101723/
And the new setup:
http://www.flickr.com/photos/edgehill/3 ... 231101723/

It's a Melles Griot 07 TRT 508 http://www.mellesgriot.com/pdf/0022.9.pdf

Depending how big everything else is you can pick up Newport RSP rotation stages quite cheaply.

Have fun

Andrew

PaulFurman · Post by **PaulFurman** » Sun Oct 25, 2009 7:29 pm

Thanks, it looks similar to the one I was looking at. I found a review & comparison of different models HERE.

Ah wow, $23 new. I saw some larger versions of those used but it looks like your fingers would be in the way when adjusting, depending on the size of the subject:
http://www.newport.com/RSP-Series-Stand ... talog.aspx

(Admin edit: to fix broken url causing blank post)

PaulFurman · Post by **PaulFurman** » Sat Dec 05, 2009 3:42 pm

AndrewC wrote:
PaulFurman wrote:Very nice setup. What is the exact model of the rotation stage above the goniometer?

I have a larger goniometer & xyz stage which were originally acquired for a home made tilt/shift view camera. I've rearranged the components into an optical bench with PB4 bellows but it lacks rotation. This is the best item I could find:

40mm rotation stage part number 124-0030 $200.00
It's a Melles Griot 07 TRT 508 http://www.mellesgriot.com/pdf/0022.9.pdf

Depending how big everything else is you can pick up Newport RSP rotation stages quite cheaply.

Andrew, I found one for a good price used but I'm wondering if it's broken. Your pic doesn't show the micrometer knob and perhaps you don't have that part... ultimately it's probably not necessary but... the knob on mine slips into a hole behind this view and if you give it a firm push, it sticks fairly well but pops out pretty easily too. I'm wondering if it's supposed to be that way or was originally glued in?

It is just the right size for my needs and came with some mounting plates & brackets that will be useful. Seems like overkill now that I have it but I'm not sure what else could be used that could be mounted firmly, locked in place, etc. Other models I looked at did not make sense for the application. However it would've been nice to have one where a knob adjusts it 360 degrees rather than just 50 degrees of rotation but most of these devices have limited range for fine control. It does have quick release and moves smoothly manually. I looked at a novoflex panorama plate for rotation of the camera before but it's a ridiculous price.

AndrewC · Post by **AndrewC** » Sat Dec 05, 2009 6:08 pm

Mine does have a micrometer, but I can't check it right now as I'm on the wrong continent. I quite like the combination of unlocked coarse and locked precision movement over a small range - makes it easy to quickly get to roughly the right place and then tweak it exactly.

Andrew

PaulFurman · Post by **PaulFurman** » Mon Dec 07, 2009 10:11 am

No worry Andrew, I don't want you to break it trying. I think mine is alright, it just needs a very firm push and holds rather well. The vast majority of the time I don't think I'll need the fine control of the micrometer anyways if people want to save money, then skip it. With a little drilling, sawing & rearranging of the aluminum brackets, I've got a perfect stage. Well, the center of the goniometer doesn't match like yours... I can move things around and make it match but other problems emerge. These things really take thought and planning, I admire the elegance of your solution.