The lens that doesn't exist

Hi lumiworx,

Thanks... In a word, "arrrgghh"! That's what I figured would be the case, but then again, processes change over time and I thought there might be a slim chance with it being the newest penny in the bank. It has some light fungus, but it looks cleanable, so I'm really hoping to get it cleaned before it's too late. Some times ya gotta do whatever works.

Well, at first blush it looks like there's just as much plastic as the 1.9c or the standard ML 1.9 - however - there are some differences that show up once they are weighed and measured.

In no particular order, and not including any front or rear caps:


I measured them all with calipers while they were collapsed at infinity focus. I don't know what accounts for the 3grams difference within .36mm of height, except the raw weight of a slightly taller mid-barrel, so I'm guessing that the optical diagram is likely the same as the standard ML 1.9 lens. My initial thought about it being close to the 1.9c is obviously wrong when you compare the numbers.

At this point I've started the UV process on the glass to kill whatever is left in there. I'll let that sit overnight to give it a maximum dose of light. I use a small germicidal fluorescent bulb for these, so they are effective and fairly quick. Once it's done it's part, I'll grab some drivers and see how to get inside. It's not going to get any better than it is withought a little help, so I might as well give it a try.

EDIT to add: lenslover ... I have several of the f/2 versions, but their exact locations eluded me for the moment, so I just used both the f/1.9 models instead.

Well... I've finally had a chance to try again at getting into the DX to do some cleanup. It turns out that the front rim/ring assembly was just being stubborn, and it does unscrew just as the ML 1.4 does. There were no holes or slots anywhere to insert a lens spanner to get the front element block out, so after some gentle attempts at simple unscrewing, it wouldn't 'back itself out', but it did turn. With a #10 scalpel (much better and far cheaper than X-Acto knives) I found a separation line to slowly pop out the block. It's a compression fit with several little teethlets holding it behind a ridge at the edge, so it wouldn't just fall out on it's own.

The UV did it's job on the fungus, and it was an easy clean off, but with the block out it showed there was also some separation on the cemented elements and it was beginning to fog in the void it left. Probably not the best design, as it seems like the glued-up block is press-fit into the molded black plastic to the point that it's impossible to push/pull the glass out. I'd hesitate to say the plastic was molded around the glass, but that's how tight it was.

As it stands now, the glass is clearer and still pretty sharp after a quick test, but I'm guessing the separation issues will get worse. For now, it's nice to have for it's rarity, but I wouldn't rush out to buy one as a shooter. The f/2 would be a better choice, and a lot easier to find. I may do a short and simple shooting test to see if there's some characteristics produced by the DX that would have made it evolutionary or show any improvements, but I'm not expecting to see anything terribly different.

The lens, after disassembly:

Slower lenses -- of whatever focal length -- are typically given the "cold shoulder" as inferior in terms of quality, simply because they are less expensive. In fact, the opposite is frequently the truth. That's OK with me, as I can find smaller and lighter lenses at give-away prices.

P.S., PLEASE don't let the secret out!!!