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RE: Eclair ACL Super-16 conversion; Shutter versus off-axis mirror spindle

Just caught this thread.

To confirm: 1) Replacing the mirror spindle with an off-axis spindle is not essential, it is a "peace of mind" thing to bring the camera up to full S-16 specs (I'm one of those guys who, when checking out the camera, will slowly advance the shutter while looking through the aperture plate, and take pride that at no time do I see the mirror passing while the shutter is open --- kind of a "pride of ownership" thing, I guess; I just like feeling that Arri has nothing specs-wise over my ACL); Without re-centering, technically the right side of every second frame receives a micro-nanosecond less exposure, but it seems to be too small an amount to have any perceptible photographic effect; [the off-axis spindle does require extra labor to install, but certainly can and is being done: Bernie O'Doherty in Boston, <A HREF="mailto:bernie_odoherty@emerson.edu";>bernie_odoherty@emerson.edu</A>, is doing them on HD-144 conversions, as well as Bruce at Arandafilm in Australia <A HREF="mailto:bruce@arandafilm.com.au";>bruce@arandafilm.com.au</A>. Many others may be as well. Bruce mentioned to me his own "peace of mind" reason to recenter the mirror --- in that way the mirror is dead center when parked, which is the position in which critcal focusing is done], but in the final analysis, cameras without re-centering the mirror give the same quality of final image, and "the proof is in the pudding." If you can save money by not re-centering, and don't care aesthetically, then you are fine not to re-center.

2) HOWEVER: replacing the 175 degree R-16 shutter with a shutter at about 140-150 degrees is necessary, to allow the mirror time to clear the enlarged aperture. (The exact number of degrees is not crtical as long as the shutter clears, but since the necessary amount is in the vicinity of 144 degrees, by manufacturing the HD-144 shutters on a computer controlled machine for precisely 144 degrees, it gives a shutter speed of exactly 1/60th second, and minimizes the width of the roll-bar when shooting off an NTSC TV at 24 fps.)

3) Many fine camera Techs can install a S-16 shutter, whether the HD-144 Shutter or their own version. (In fact, for the least possible expense, a piece of black tape can be placed over the R-16 shutter to close it down --- I'm not recommending this, but it has certainly been done in a pinch). A list of techs can be found on my site at: www.members.aol.com/Super16ACL. 4) I do recommend modifying any mag rollers that contact the emulsion side, since an emulsion scratch is irreversible (and there are only a few such rolers, so the cost is trivial). The Super-16 support should be taken down to .7mm. After that, run scratch tests. A pristine ACL mag should not scratch anywhere --- but mags are 20-30 years old, so on a well used mag some rollers or the aperture plate may not be as pristine as they once were.

5) As of Jan 1, 2002, if you order a part from www.members.aol.com/Super16ACL, remember to mention this Topica List for a 20% discount. A lot of people have been steered to me in recent months via the list, and as a result my investment in making the HD-144 kits is getting whittled down (still not at break-even), so I can return the favor. (I never had planned to be in the parts business --- but it was so expensive to make just a few for my own camera --- especially the new aperture plate, and the R& D costs on the Shutter counterbalance until it came out perfectly --- that it seemed sensible to make a large batch to sell kits to defray the cost. Frankly, if I'd known when I started how much the prototyping process bleeds out of you, I don't think I'd have begun.).


PS - I think it's great that there has been such an explosion of interest in Super-16 ACL conversion over the past year or two. Regardless of which excellent Tech is doing the install, and whether it is with in-house parts, converted R-16 parts, or the HD-144 kit, the fact that there has been a kind of revival in the ACL for HDTV and 1.85 blowup is very exciting --- many people who would have otherwise gone over to mini-DV seem to have found Super-16, and that is great for filmmakers the world over who want to keep film alive and well. And new 3rd party accessories for the ACL , such as motors, are now being marketed. And both OEH in the USA and Les Bocher in England are still making all kinds of other accessories, such as lens adapters etc. And Les is also now doing very cost-effective conversions of R-16 zooms to S-16. My next hope is that we'll find a way to make conversion of the 200' mag to 350' an economical reality. I'm going to work with the folks down-under on this --- the great thing about the ACL revival is that it's kind of like Linux; everyone is doing it for the love of it (even if they also make a livlihood off it), and people are very willing to share info on the technology. Also, kudos to Ray (the list Mum) for building up this site!

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