MOD - closer focus of 0.78m - Leica 35mm F1.4 Summilux-M lens v2 Canada

 Hello, this article is one more practical exploration of close focus mod for Leica mount lens. This time I'm working with Leica 35mm F1.4 Summilux-M v2 Canada lens provided by FredMiranda forum member lifeandmylens (thank you very much Shawn!). Out of factory lens is able to focus down to 3ft only, and there is relatively easy way to customize focusing down to about 0.78m.



Close focus mod details

Modifying closer focus for first models of Leica 35mm F1.4 Summilux-M is not something new. As mentioned in earlier Steel Rim Reissue mod article, you can check "details on modifying close focus in one of Leica Summilux-M 35mm F1.4 lens model performed by danielcai and shared on Leica Forum in article Summilux 35mm f/1.4 Pre-ASPH V2 close focus mod. "

Technically I'm performing modification similar to #2 described in that article, but instead of any lens drilling decided to introduce mechanical change that can be easily reverted to lens original condition. A bit closer focusing modification is definitely possible, though involving grinding of lens parts, and I'm not going to do that.

Lens disassembly steps

First the aperture ring need to be set to F5.6 and then accurately unscrewing lens optical module from focusing frame in CCW direction. It's important to memorize its screwed in position for precise assembly later.


Next steps is to accurately partially unscrew three tiny bolts on the focusing ring, and taking it off.


At this point flip focusing frame to look at inner components. There are two thick black metal bars at 2 o'clock and 8 o'clock. They are limiting focusing ring rotation at infinity and 3ft correspondingly. When focusing a thinner black metal bar is moving radially between these bars, visible at 1 o'clock on picture below. 


Next I'm unscrewing bolt holding bar at 8 o'clock, and removing that bar from frame.


Then I'm cutting 3mm wide brass strip, and forming it in a circular arc shape.


 Left end of that strip is folded, then edge is fine grinded to form flat surface. It is going to be a new stopping point for close focusing. 


The right edge of curved strip will touch the bottom of 2 o'clock focus stopping bar. When inserted, brass strip is setting new stop location for close focus. Picture below shows focus ring moved to infinity stop.


And this picture shows how focus ring is now stopping at closer focusing position.


It is possible to make this brass arc shorter and allow closer focus, but there is focus cylinder helicoid guider that will touch internal RF cylinder and may slightly jam there, so I'm stopping focusing before that happens. So lens focusing operation remains silky smooth and light, with crisp and clean stop at about 0.78m distance, and focus helicoid guider is not yet touching internal ring.


Then I'm attaching focus ring back to it's original position, which can be traced by dedicated grooves made for three tiny bolts holding it on inner focusing cylinder. As you can see here is new and shorter minimal focusing distance.


Finally I'm screwing in lens optical core of Leica 35mm F1.4 Summilux-M to it's original radial position.


Last cosmetic change required is to protect bolt socket from dust by applying small vinyl film sticker.



It's important to keep removed metal bar and bolt in a safe place, preferably the lens box, so it can be easily reverted to original focusing range.

RF precision testing shows that lens is slightly front focusing at 0.78m, which technically requires fine reshaping of RF couple cylinder. At the moment of working with lens I got confused and was thinking that RF couple requires elevation to compensate front focusing at new range, but in fact it requires precision grinding off and lowering RF couple cylinder edge. I shipped lens back prior to understanding that. So it's possible to perform some grinding and make lens precisely focus with RF at new closer distance, though that change is not reversible.

Conclusions

Leica 35mm F1.4 Summilux-M lens v2 closer focus mod complexity is relatively low. Most challenging part is to accurately unscrew and screw in optical core. Crafting new brass stopper is very easy as well as removing default focusing blocking bar. So if you have proper skills, this modification may take less than a hour. You may even ask closest available lens repair technician if they could do such simple mod for your for some fee.

About lens modification requests

I'm already receiving requests from blog and forums readers asking if I could repeat the close focus mod for their Steel Rim Reissue, or Summilux-M v2 lens. Thank you for your interest, though it's important to clear up few things. I'm performing these exploratory discoveries and publishing details with hope that you can find skilled lens repair technician who could follow shared steps to repeat the mod, and yes it would be fair to pay them corresponding labor fee.

Personally, I have limited time dedication to this photo equipment hobby, and keep it separated from my daily job. Sometimes I'm spending hours and days researching, and some lens mechanical work is also quite labor and time costly. If I start taking modification orders, it will significantly cut off my hobby time, which I'd prefer to keep free for new explorations. So I'm grateful for your feedback, and hope you can find that person willing to help you with skilled lens modification. If they have any questions, I'll be more than happy to respond and add extra details or explanation to the article.







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