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Richter Field Collimator


James Steven Beverly

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Guest John Adderley
Has anyone ever used one of these and exactly how do they work?

 

I have a little field collimator made by Thomas Thomosy in Canada. It's cheap and cheerful and always works. What it does is to show me that a lens is correctly focussing to infinity when I put it on any of my cameras. I just put little strip of reflective silver gel in the gate where the film goes and make sure the pressure plate holds it up against the aperture plate. The with the shutter open I can switch the field collimator on and point it into the lens and see an image of the collimator's focusing screen. The screen is sharp when the lens is at infinity. If I then also swing the mirror over to view through the viewfinder I can check the ground glass is correct at the same time.

There are instructions on the web as to haopw to make these instruments so STFW.

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  • 1 month later...
I have a little field collimator made by Thomas Thomosy in Canada. It's cheap and cheerful and always works. What it does is to show me that a lens is correctly focussing to infinity when I put it on any of my cameras. I just put little strip of reflective silver gel in the gate where the film goes and make sure the pressure plate holds it up against the aperture plate. The with the shutter open I can switch the field collimator on and point it into the lens and see an image of the collimator's focusing screen. The screen is sharp when the lens is at infinity. If I then also swing the mirror over to view through the viewfinder I can check the ground glass is correct at the same time.

There are instructions on the web as to haopw to make these instruments so STFW.

 

Hi John. What collimator are you using? Will it work with HD as well?

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William Wages, ASC has one of those and he was showing me how it works just the other day on the set of "Big Love". Seems pretty nifty. Of course, if the collimation is off, you won't know if it's the lens or the camera mount, but at least you know if it's off...

 

Since with an HD camera & lens you can easily adjust the back-focus, in a sense, you don't need to check the collimation -- it's basically "off" until you set it yourself using the typical back-focusing techniques.

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Hi.

I use a few versions or russian collimators and collimator tubes, collimator bentch with focal length 180...2000 mm.

This was collimators with one fixed position - infinity, auto collimator with possiblity to adjust of distance focusing of lens, small collimation tube and big collimator bentch.

I think, the version of collmator need choose for your needs.

If you need test of camera and lens only, this can be simply collimator tube with not high speed of optical system, compact and low weight.

You can take this collimator on expedition and test of camera and lenses.

But, if you need lab device, this must be a big weight, fast speed collimator with many focus positions , with high precision.

If anybody interesting, i cans end pictures and description of russian collimators.

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William Wages, ASC has one of those and he was showing me how it works just the other day on the set of "Big Love". Seems pretty nifty. Of course, if the collimation is off, you won't know if it's the lens or the camera mount, but at least you know if it's off...

 

Since with an HD camera & lens you can easily adjust the back-focus, in a sense, you don't need to check the collimation -- it's basically "off" until you set it yourself using the typical back-focusing techniques.

 

 

With a HD zoom yes, it's pretty straight forward, but it's not so easy when using a 35mm adapter and 35mm primes. That's why I asked. I guess I should have mentioned it :)

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Has anyone ever used one of these and exactly how do they work?

 

Good morning James,

 

I used the Richter collimator for over thirty years of cine lens and camera repair and manufacturing. It and the Zeiss units are to be found in every rental and manufactures facility. What it does is provide a image of a 1951 airforce resoultion reticle focused at infinity. You can check the accuracy of the collimator by unscrewing the eyepiece and mounting it where the light source would generaly be attached and looking at an object at a distances equalling infinity. We use to use the moon when it was about half full as the terminator provided a sharp image of infinity focus. Then if the reticle and the lunar image were in focus at the same time you knew the collimator was in proper adjustment.

 

Chuck Colburn

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William Wages, ASC has one of those and he was showing me how it works just the other day on the set of "Big Love". Seems pretty nifty. Of course, if the collimation is off, you won't know if it's the lens or the camera mount, but at least you know if it's off...

 

Since with an HD camera & lens you can easily adjust the back-focus, in a sense, you don't need to check the collimation -- it's basically "off" until you set it yourself using the typical back-focusing techniques.

 

Good morning David,

 

If the film plane and the ground glass are showing the same relative image in the collimator eyepiece then chances are that any error in collimation is within the lens being checked.

 

Chuck

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With a HD zoom yes, it's pretty straight forward, but it's not so easy when using a 35mm adapter and 35mm primes. That's why I asked. I guess I should have mentioned it :)

 

Well in that case, you take care of the lenses exctly the same way that you would take care of them if they went out in any other package. The trick there is that many of the 35mm adapters don't have very well thought out provisions for adjusting flange focal depth. I'm shooting a short right now with the director's Redrock adapter and it's a pain in the ass. It took me 4 hours to get the flange focal depth perfect so that lenses' footage markings would be accurate and the next time I took it out of the case it was off again. I've given up on that and am just eye focusing and putting up with the scale inaccuracies.

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  • 3 years later...

Hi,

I just bought a russian collimator http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=390249357862&ssPageName=STRK:MEWNX:IT

I need it, because I have an anamorphic lens set in oct19 mount, but In order to rent it to be used on the RED I will have to switch sometimes mounts to PL. I have a OCT19 mount for the RED, but unfortunately, the owner of the RED does not want to change mount on the camera itself.

 

Now I have no idea of how this things work...

But if someone can tell me where to find a english manual, or some literature abouth this it might be of great help.

 

thanks

Daniel

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  • 3 weeks later...

Hi,

I just bought a russian collimator http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=390249357862&ssPageName=STRK:MEWNX:IT

I need it, because I have an anamorphic lens set in oct19 mount, but In order to rent it to be used on the RED I will have to switch sometimes mounts to PL. I have a OCT19 mount for the RED, but unfortunately, the owner of the RED does not want to change mount on the camera itself.

 

Now I have no idea of how this things work...

But if someone can tell me where to find a english manual, or some literature abouth this it might be of great help.

 

thanks

Daniel

 

Hi Daniel: I am in the same bout. Have Lomo snamorphs and a Richter collimator, but looking for steps to set up the collimator and chnage mounts on the LOMOs. Please share if you find something. I will do the same. Thanks, Mike

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