The main story discussing the need and want of a tab (or not) on a 50 'cron seems to have invoked the further finding that at those times during which these things were indeed produced, they existed either as a convex or a concave version (e.g. http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=004KA3 and http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=004hKq).

Now FWIW, those lenses (Article 11819) of S/N 2915801 onwards (1979-1982) had convex tabs, whereas those of S/N 3098901 and later (1982-1994) had concave tabs. That's all. I need and want a 50 'cron with a concave tab just like those on the present day 21, 24, 28 and 35 mm Ms, and maybe any other newbies wouldn't mind knowing what to check for either.

Mike

-- Michael Kastner (kastner@zedat.fu-berlin.de), September 06, 2001

Answers

Lord, save us! What next? Crosshead screws versus flathead?

-- Robin Smith (smith_robin@hotmail.com), September 06, 2001.

Help:

Lord save us indeed.

See my previous posting about "arcanity". Forget about flathead vs Philips screws: what about the galactic question of angels on pinheads? Do pinheads made in Germany have less friction than those made in Japan, or Rome?

Sheesh!!!

-- RICHARD ILOMAKI (richardjx@hotmail.com), September 06, 2001.

Doesn't sound arcane to me at all: it sounds like a serious functional concern at the point of interface between the photographer and the lens. I prefer the concave tabs, too.

-- Michael Darnton (mdarnton@hotmail.com), September 06, 2001.

Mike,

I have a concave tab on my 50mm Summicron and a convex tab on my 35mm Summicron. These are my most used lenses for my Leica M cameras, and there is no problem operationally with either shape. I can switch back and forth effortlessly, with no noticeable reduction in capability based on the tab.

I mention this only because if a lens presents itself to you with the rounded convex tab, it should not be immediately rejected because of this purely cosmetic feature. The optics are the same, and when you are looking through the finder, you can't see what shape the tab is... but your left index finger will fall right in place.

-- Al Smith (smith58@msn.com), September 06, 2001.

Mike:

I'm with you and Michael D. I don't agree with the others that think this is another arcane post. How we interact with our gear is a matter of personal choice. If you want the concave tab, go for it! I also prefer the concave tab and would be willing to pay an additional premium just to get it.

Cheers,

-- Jack Flesher (jbflesher@msn.com), September 06, 2001.

cable ties... 1 for a convex tab, 2 for a concave... ;o)

-- Lutz Konermann (lutz@konermann.net), September 06, 2001.

. . . and I have the convex tabbed 50, and wish it were concave. All my other lenses with tabs are concave. The convex one feels wrong, foreign, to my fingers. One of these Saturday mornings, I may have to fire up the Dremel Moto-Tool in the basement to correct this. But is the tab metal or plastic? If metal, the operation would leave a bright shiny surface. Does anybody know?

-- Bob Fleischman (RFXMAIL@prodigy.net), September 06, 2001.

An idle mind is the Dremel's workshop.

-- Mani Sitaraman (bindumani@pacific.net.sg), September 06, 2001.

I think the more serious question is to tab or not to tab. I have some of each and have really grown fond of the tabs.

-- mark (mramra@qwest.net), September 06, 2001.

The tabs on my Summicrons (50 and 35) let me follow-focus as well as good autofocus, with focus exactly where I want it, moreover. The downside of this technique is that subject tend to get centered :-(

-- Mani Sitaraman (bindumani@pacific.net.sg), September 06, 2001.

I use the present version of the Summicron-50, the one without tab. However, I bought the concave tab (from the previous model of the Summicron-50) as a spare part from Leica (about 15 US dollars a few years ago) and had a repair-man mount it on my lens. It fits perfectly, and since I prefer the concave version (much faster than the convex)and also have the same type on my other lenses, I am quite satisfied. And it is a benefit to also have the serrated ring for focussing, since I sometimes prefer this to using the tab (especially when taking portraits or other pictures with the camera "standing- up").

-- (goran.bjerklow@swipnet.se), September 07, 2001.

So to summarize the above responses, it's either "concave" or "I don't care". Does anyone *prefer* convex?

-- Michael Darnton (mdarnton@hotmail.com), September 07, 2001.

Bob Fleischman:

Might you be able to buy the concave tab and simply replace your convex one with it?

-- Jack Flesher (jbflesher@msn.com), September 07, 2001.

"Dear Bob and Jack" -- here are a few answers from Solms:

• Concave tabs are apparently still available as spare parts and can also be added or replaced (on an M-lens which already had one).
• The tabs are to be screwed in from the inside of the focusing ring, meaning that the whole barrel first has to be dismounted, then remounted and at last readjusted optically.
• This is not possible for the present day 2/50 due to steric problems. Neither the addition of a tab to the focusing ring present, nor the exchange of the focusing ring present with a whole new ring inclusive of tab is possible.
• This can only be done by Leica itself or by a Leica-authorized repair shop.
• No price estimates were given.

Somehow, I can now understand Robin a little (but just a little) :-»

-- Michael Kastner (kastner@zedat.fu-berlin.de), October 18, 2001.

Convex tab is for those, who have a concave finger, and vice versa :?)

-- Victor Randin (ved@enran.com.ua), October 18, 2001.