WTB Arri Bayo --> Aaton adapter

adam berk · September 26, 2007

If anyone has an arri bayo 2 aaton adapter they could part with, email me @

adam at b-mp.com

I'm looking for the lever-lock one that just goes on the camera and lets you switch lenses as usual.

thanks,

adam

Tim Carroll · September 26, 2007

Adam,

Got one left.

Back when I had an Aaton LTR I had all my mount adapters calibrated. Be aware, depending on who made the adapter, they can throw your FFD off if they are not dead on 12.00mm. (And if your FFD is off, your image will be soft when using normal to wide angle lenses).

The one I have for sale is calibrated at exactly 12.003mm, so it is three thousandths of a millimeter long, which will not effect your FFD. Some of the less expensive adapters are not that accurate and I've seen them as short as 11.985mm which would effect your FFD and give you soft images.

I'm selling this one for $250, if you're interested.

Best,

-Tim

PS: By the way, even with the lever lock adapter, you still need to put the adapter on the lens, then put the lens on the camera, to get everything to seat properly. You cannot leave the adapter on the camera and just take out the lens and switch them. The lever lock makes switching lenses much faster and easier, but you still need to remove the lens and adapter, put the adapter on the new lens, then put the lens and adapter back into the camera.

Mitch Gross · September 26, 2007

PS: By the way, even with the lever lock adapter, you still need to put the adapter on the lens, then put the lens on the camera, to get everything to seat properly. You cannot leave the adapter on the camera and just take out the lens and switch them. The lever lock makes switching lenses much faster and easier, but you still need to remove the lens and adapter, put the adapter on the new lens, then put the lens and adapter back into the camera.

Interesting, as I had the identical adapter for 12 years and always would leave it on the camera, just swapping the lenses. Perhaps the issue was with your lenses and not the adapter. I had no problem with my Illuminas.

BTW, we have these adapters brand new at Abel in NY.

Tim Carroll · September 26, 2007

Interesting, as I had the identical adapter for 12 years and always would leave it on the camera, just swapping the lenses. Perhaps the issue was with your lenses and not the adapter. I had no problem with my Illuminas.

Mitch,

Never mentioned having any problem with the adapter on my Aaton camera with my Zeiss Super Speed Mk1 lenses, not sure where you got that from.

Just going by what the Aaton manual says. "It is highly recommended to leave Aaton adapters on lenses already fitted with other mounts." And talking with a friend who has been using Aatons for many years, and he recommended what I described above, always take the lens and adapter out of the camera, switch the the mount to the new lens, and put it back in. He said that otherwise, the lens may not seat properly in the adapter, and as you know, even being slightly off is a big deal with FFD and sharp focus.

By the way, last time I talked with Nathan, he said you guys didn't have your adapters calibrated. Are you guys doing that now? And what are you selling the new lever lock adapters for?

Best,

-Tim

Nathan Milford · September 26, 2007

I generally callibrate the lens to the adapter to the camera mount.

I set the flange on the camera properly, then I shim the lenses to work properly on the adapter mount and lastly I set screen focus to match film focus. It really isn't a problem and I think people's fears about adapter mounts are typically overblown. I shim the lenses just because I'm obsessive compulsive, but they'd look fine on any other camera or adapter assuming everything is within spec... I just like absolute precision when it is attainable, but there is enough fudge room.

Zeiss quotes something like +20 to -20 microns as tolerance for the superspeeds and I've never seen an Aaton or ARRI PL adapter out more than 5 microns...

The real problem is when a tech will set the flange or back focus arbitrarily to just work as a closed system instead of using proper tools to set everything to the accepted standard specs. I am shocked every time I hear of a rental or repair facility that doesn't use a modern collimator and instead sets the lenses to the camera. Some places will making everything plus or minus so everything matches in the set (camera and lenses) making a closed system. It causes problems when you use the lenses on a foreign camera body or foreign lenses on the set body.

Long story short, you ought to be able to slap the adapter on with no problems assuming your lenses and flange are set properly in the first place.

Tim Carroll · September 26, 2007

Nathan,

Your system is very similar to mine. I first set the FFD on the camera body so it is dead on to spec. Then I carefully measure the adapter (I set it up with gauge blocks and measure it to .002 mm) to make sure it is within spec. Then I collimate the lenses to make sure they are in spec. That way, the camera operator can take that camera body, and that adapter (which since we are talking about the lever lock adapter, we can assume the operator is going to be swapping it on different lenses) and put any collimated lens on there and he or she is good to go. Your way of collimating the lens after the adapter is mounted is great, as long at they are the screw on "permanent" type of adapters and they stay on that particular lens. I don't consider the lever lock adapter to be of that type, which is why I think you need to calibrate the lever lock adapters to make sure they are 12.00mm since camera operators are going to be swapping them between different lenses.

Like I mentioned above, I have seen Aaton-ARRI mount adapters off as much as 11.985, or 15 thousandths of a millimeter, which for me, is out of spec enough to cause focus problems. I see this much more so with ARRI PL mount adapters, probably because there are so many more of those in circulation, and the quality on many of them is really questionable.

Best,

-Tim