Chamonix and Intrepid rise-fall/tilt knobs

[ramesesjd]

Hello all,

I've noticed that the new Chamonix, Intrepid and Chroma cameras come with knobs on the front standard that are able to independently control rise-fall and tilt. I'm very intrigued by this and would like to incorporate such into my own LF camera or its in-conception stage descendants. I haven't a clue how these 'dual action knobs' work or if that's even the correct term for them. Can any one provide a description of this or link to one, please? Also, are these knobs commercially available in quantities for a hobbyist, or are they custom machined?

A brief search online didn't turn up anything, most likely because I don't know the words to ask the questions with. I've not been lurking on the forums as often as I used to so my apologies if these are questions already asked and answered.

Many thanks,
-R

[DDrake]

Hello all,

I've noticed that the new Chamonix, Intrepid and Chroma cameras come with knobs on the front standard that are able to independently control rise-fall and tilt. I'm very intrigued by this and would like to incorporate such into my own LF camera or its in-conception stage descendants. I haven't a clue how these 'dual action knobs' work or if that's even the correct term for them. Can any one provide a description of this or link to one, please? Also, are these knobs commercially available in quantities for a hobbyist, or are they custom machined?

A brief search online didn't turn up anything, most likely because I don't know the words to ask the questions with. I've not been lurking on the forums as often as I used to so my apologies if these are questions already asked and answered.

Many thanks,
-R

Hi R,
I was also interested in Chamonix/Intrepid style dual knobs, and couldn't find anything available so I designed and made my own. Haven't used them for a camera yet (camera design isn't finished) but they seem to work.

The trick is to have a hollow bolt that locks rise/fall while a smaller diameter bolt runs through the hollow center and acts as a tilt axle and lock. I used 5/16-16 socket head cap screws for the hollow bolts, drilled out to accept 10-24 socket head cap screw. Had 10 hollow bolts drilled out by a machine shop at a cost of about $3/ea. Knobs are 3D printed plastic, bonded to the bolts by heating the bolt heads and pressing them into the knobs. A little hard to explain. I'll post pictures of the assembly when I have a chance, which should make things more clear.

[Peter De Smidt]

Thanks for the info, David. I look forward to the pictures.

[ramesesjd]

Hi David,

Thanks for the pointers and details. I've been sketching out ideas for a few days and I've come up with something very similar to what you describe. I've found these hollow bolts on AliExpress that might work for this type of design:
https://www.aliexpress.com/item/32754398189.html
https://www.aliexpress.com/item/32960645334.html
https://www.aliexpress.com/item/32856112744.html

Seems like these bolts are used in lamp housings. I'm not sure but the style of bolt in the first link could obviate the need for the plate I describe to prevent rotation around the rise/fall bolt. As you've already got your hollow bolts these links may be of little use to you, but perhaps someone else will find them useful at least as starting points.

In addition to the hollow bolt, I'm also thinking to have a plate ride within the rise/fall slots on the standards to ensure that the frame doesn't rotate around the rise/fall bolt. I'd like to 3D print some parts to test this idea. This is some way off yet, but I'll post pictures when I have these printed. This should also clarify how the mechanism would work to separate rise/fall from tilt. I look forward to pictures of your design.

Kind regards,
-R

[DDrake]

The style of bolt in the first ali express link looks like it would work well, but if the actual bolt is 12mm diameter, that seems pretty chunky.

Here's pics of what I did. Note the wide plastic piece the hollow bolt is pressed into, with lugs that engage the slot in the standard preventing rotation, just as you suggest. The middle knob has a 5/16"-16 nut pressed in to a recess, and the top knob (tilt knob) has 10-24 cap screw pressed through it. I model the printed parts with slightly undersized holes where the bolts and nut press in, and extra wall thickness, then heat the bolts and nut before I push them into place. The plastic melts and hardens around the steel, and makes a very secure hold. I suppose knobs could be machined from steel or aluminum and bolts and nuts seated with an arbor press, but I doubt the machine work would be cheap.

[Peter De Smidt]

Great work, David!

[Tin Can]

Off the shelf Dual Shaft Knobs exist, but are often specialized for other purposes.

Examples below, I have not used any of them for cameras.

https://www.surplussales.com/SHAFTHARDWARE/Knobs-8.html

https://www.amazon.com/Estone-Black-.../dp/B00J5ZQ3A2

https://www.ebay.com/sch/i.html?_nkw...&ul_noapp=true

[ramesesjd]

Very nice work, David! Thanks for sharing the photos.

Tin Can, thanks for the links. It seems those style of knobs would work for rotary pots or rotary encoders. I'm not sure how they'd mate with a bolt/axle for camera movements, but if they did it would be a very convenient off-the-self solution.

-R

[Peter De Smidt]

Here's the question, though: Do we really like concentric knobs in use?

[ramesesjd]

On a LF camera, I've only ever used combined rise-fall/tilt controls and been annoyed by them. I've also never used a camera with completely independent movement mechanisms (like the Arca Swiss, I think), so I haven't that basis to compare either. I'm not sure how these dual control knobs are to use in practice, but it's a neat mechanical problem to puzzle through at least. From the few reviews I've seen of the Chamonix cameras with the dual knob, it appears that people like them. Do you have experience with or thoughts on these controls, Peter?

Outside of photography, I've used a few older scientific instruments with dual knobs where the outer knob was very low profile and usually had a locking pin to keep it from being moved inadvertently. Those outer knobs usually controlled coarse parameters not meant to be jiggled on a routine basis (e.g., coarse focus/working distance on an electron probe). For those purposes, I quite liked concentric knob controls for how space efficient and logical-in-use they were/are.