ROM lenses on the SL?

Up to now the answer has been no they cannot be modified safely to fit

because then the lens would also fit the Leicaflex Standard and SL2, whose

cam followers for the first cam would foul the ROM contacts.... but I think

I've figured out how to do it with minimal modification to the hardware and

full compatability while preventing hardware damage from bad lens/body

combinations. I've run the idea past DAG and he says it ought to work.

<P>

The two differences between the SL flange and the R flange are a slightly

larger inside diameter on the R flange and a slightly shorter bayonet lug

on the body at the 12 o'clock position, with a correspondingly longer

bayonet lug on the lens but (this is crucial) only on those lenses that

would interfere with the SL's mirror. The bayonet lug size change was made

beginning with the SL2 and the longer lug on the deep back-focus lenses

prevents their use on the SL or Leicaflex Standard (where the mirror would

hit the lens).

<P>

The only ROM lens I've had is the 80-200 f/4 (now a 3-cam lens), which has no

mirror clearance problems. The flange that originally came with the lens

requires the R-only larger inside diameter along with the shorter bayonet

lug for the lenses with no clearance problems. If - a big if - Leica has

beeen consistent about using the longer lug on the deeper lenses, then one

could:

<P>

) put the SL's metering cam on the ROM lens, leaving the ROM stuff and the

lens' flange alone

<P>

) enlarge the inside diameter of the SL's flange to R specs, leaving its 12

o'clock lug alone.

<P>

The modified SL would then accept any R lens that doesn't have mirror

clearance problems and would still fail to mount the deeper lenses. The

lens would still be incompatible with the Leicaflex Standard and SL2, so

that the ROM contacts won't be fouled by these bodies' first-cam follower,

but would fit the modified SL and (because of its retrofitted 2nd cam)

meter correctly. Since the SL doesn't use the first cam it wouldn't damage

the ROM contacts.

<P>

According to Don Goldberg the modifications to the lens and SL are both very

simple. Note that this will not work with the SL2 or Standard - only the SL.