Robert_M Posted August 7, 2011 Share #1 Posted August 7, 2011 Advertisement (gone after registration) I recently received my Perar II lens from MS Optical Super Triplet Perar 3.5/35 Mark II | japan exposures and am happy with the lens. It is what I expected for the optics and the mechanics. It is an interesting lens for making the whole M9 package super compact and portable in a "pocket" as others have discussed. However, there are some issues in coding this lens which I'll point out in this new thread. Since I haven't seen this discussed anywhere, I've taken the the liberty to start a new thread. I have coded all my Leica and CV lenses myself and am very familiar with the codes and how to implement the codes. After some experimentation, I found that the 35 f/2.5 coding was the best fit for this lens. This matches what others have found. Now to use this code, one must physically code the lens since that option is not available in the M9 menu for manual coding. Not really a problem, since I prefer to physically code all my lenses to avoid memory lapse. The Perar II lens has conveniently put in a coding groove in the lens flange. In my lens, this groove was not black anodized like the rest of the lens flange (contrary to the pictures on the Japan Exposures web site). So coding was done with some black flat paint, leaving the aluminum surface for the white. This works fine under normal circumstances. However, the Perar II lens has 2 features which seem to cause some issues with detecting the coding. First, the Perar II lens flange is only 49.9mm in diameter. To completely cover the M9 lens coding diode array, it is necessary to have a flange of at least 51mm in diameter. All my other lenses (and extensive list) have at least this flange diameter. The result is that the two ends of the coding diode array see outside the lens flange. I've attached a picture which shows this on my camera. On the Perar web site (at the above link) one can see this in their photos also if one knows what to look for. To help the viewer, the screws on the M9 mount flange are on the same diameter circle as the diode array. So if one sees parts of the flange screws, the diode array is also not covered completely. Secondly, the groove for the coding area is milled out to the full diameter of the flange (it is not a groove, but a cavity). So, there is some additional light leek into the diode array area. The result is that the coding of the lens works fine in moderate lighting. I have no problems indoors with the M9 properly detecting the lens code. However, out in bright sunlight, there is too much stray light that hits the diode array (since it is not properly shielded) so the lens detection no longer works. Here are some solutions I've come up with: 1) Shield the area of the flange that is near the diode array with my finger to prevent the stray light from hitting the lens coding diode array. This works, but it is cumbersome and not a satisfactory solution. 2) Use some gaffer's tape to cover the exposed lens coding diode array after mounting the lens. Those who like gaffer's tape to cover their red dot probably like this solution. It works, but is not elegant. 3) I made a coding drawing and printed mask which fits the lens coding area with the proper code. I printed this out onto some standard label material on a printer. I left extra area to stick out and cover the diode array area. If anyone wants, I can generate a pdf file of this and post it here. This solution only works if the paper or label material is very dense. With thin white label material, the light still shines through the label. 4) I have thought about making a short, curve piece of a metal ring to attach to the outside of the lens flange to extend the flange diameter in that area. I haven't experimented with this yet. So far, I haven't found a solution I'm thrilled with. Have others noticed this issue? Or, are other users just happy with uncoded lens settings? Maybe I live in a sunny climate and other users have dull light, so haven't noticed the issue? Feedback would be helpful. Thanks. RM Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/158826-perar-ii-lens-coding-for-m9/?do=findComment&comment=1758682'>More sharing options...
Advertisement Posted August 7, 2011 Posted August 7, 2011 Hi Robert_M, Take a look here Perar II Lens coding for M9. I'm sure you'll find what you were looking for!
MarkP Posted August 7, 2011 Share #2 Posted August 7, 2011 Thanks for posting this Robert. Very interesting observation. Dirk coded the lens for me for the 2.5/35 Summarit before the lens was sent out so I didn't have to do it myself. Have just looked at the lens on the M9 and I see exactly what you mean. I haven't noticed a problem with the exposed sensors yet as I've only just started using the lens recently. However, with palm of my left hand supporting the camera weight, and thumb and index fingers around the bottom of the lens for aperture and focus adjustment I would probably be inadvertently shielding the sensors from stray light. Have you contacted Dirk about this? It would be an appropriate modification for the Perar III, I doubt it could justify a recall on the Perar I & II. I should add that although I'm overall happy with the lens I find it most annoying that it doesn't lock in when collapsed and slides in and out depending on the position of the camera Mark Link to post Share on other sites More sharing options...
250swb Posted August 7, 2011 Share #3 Posted August 7, 2011 My Perar I covers the sensor completely so I wonder if it is only a problem with the II? Steve Link to post Share on other sites More sharing options...
Robert_M Posted August 7, 2011 Author Share #4 Posted August 7, 2011 Steve, That could well be. The 1st version was LTM with adapter pre-attached; isn't that right? So it has a different flange. I, of course, have been communicating with Dirk well before posting here for input. In fact, he suggested I post something here. Dirk has been very helpful and is also curious about input from others. He tells me that this same flange (version II) is used for the other conversion lenses that they offer. RM Link to post Share on other sites More sharing options...
250swb Posted August 7, 2011 Share #5 Posted August 7, 2011 As I undertsand it Robert the first version appears to be LTM in origin, but couldn't actually be used as an LTM (if you could take the adapter/flange off). I think the adapter style mount was just a jumping off point for the overall design? Steve Link to post Share on other sites More sharing options...
Robert_M Posted August 8, 2011 Author Share #6 Posted August 8, 2011 MarkP, Thanks for the reply. I didn't see your post when I replied to this thread last. I think this forum software may have some issues with timezones and everything doesn't pop up exactly right. Yes, I think you are probably shielding the lens coding diode with your hands. Try it out in sunny weather on the sand, and then check the "info" button on the M9. Is it still coded? You should be finding plenty of sunny days in Oz like we have in the US SW. Dirk has been very helpful. I wouldn't think of suggesting that this is some problem which constitutes some condition of "recall". This is a specialty, custom lens, limited production item. It may have "features", but that is to be expected with custom items. I'm far more interested in suggesting improvements for the next iteration of production if changes are made. If we can suggest improvements for them, all the better. I see your point about the locking of the lens in collapsed condition. That hasn't bothered me so far. I expect to put it in a compact belt case when I collapse it, so this isn't an issue. RM Link to post Share on other sites More sharing options...
MarkP Posted August 8, 2011 Share #7 Posted August 8, 2011 Advertisement (gone after registration) Thanks Robert, I'll report back when I've had a chance to test the lens when working in bright light. Regards, Mark Link to post Share on other sites More sharing options...
JapanExposures Posted August 10, 2011 Share #8 Posted August 10, 2011 As I undertsand it Robert the first version appears to be LTM in origin, but couldn't actually be used as an LTM (if you could take the adapter/flange off). I think the adapter style mount was just a jumping off point for the overall design? Hi, this is correct. I will try to test this coding issue with my own setup as well. I have not heard from anyone else with this problem so far. If it is a camera/lens combination problem or one-off lens is too small then we can swap the lens. Let me know if you cannot solve it please. Link to post Share on other sites More sharing options...
tdtaylor Posted September 27, 2011 Share #9 Posted September 27, 2011 Never noticed it before, but my Perar II definitely leaves the diodes exposed. Link to post Share on other sites More sharing options...
Robert_M Posted September 28, 2011 Author Share #10 Posted September 28, 2011 Terry, Do you use the Perar II uncoded, manual coded, or coded with lens detection (and appropriate paint on the lens mount) on the M9? RM Link to post Share on other sites More sharing options...
tdtaylor Posted September 28, 2011 Share #11 Posted September 28, 2011 RM, I currently have the lens uncoded. I have one of my User Setting set to manual lens detection and 35mm f2 11310/11311 ( I found I often don't remember to change from manual to auto for lens detection, but I do check the settings when I pick the camera up). My camera has been at Leica, and haven't had a lot of time to experiment with the manual setting available, but this manual setting appears to work fairly well. Since every other lens I have is coded, I would prefer to have this one coded, but the exposed diodes may not make this possible without a fair amount of inconvenience. I am open to any straight forward, simple solution. Link to post Share on other sites More sharing options...
brill64 Posted September 30, 2011 Share #12 Posted September 30, 2011 Although the Yen is currently quite expensive, it's great that you are supporting the Japanese economy by buying this great little lens. From what I've read about the Perar, it has achieved cult status amongst Leica users in Japan and personally, I am considering to buy a copy myself. I read on the Japan Exposures website that they decided not to code it because opinions differ on how best to code so I guess that ultimately it comes down to personal choice. What is interesting is that the m-mount appears to be the same as my ancient (older than me) Leitz Elmar 3.5cm, which when mounted on my M9 almost fully exposes the 6-bit reading diode. Since I manually code with this lens on anyway, I've never really found it to be an issue, except possibly on an M8, where coding is necessary but even then I've not found any anomolies. Will post a pic mounted on my M9 later for you to see. Link to post Share on other sites More sharing options...
brill64 Posted September 30, 2011 Share #13 Posted September 30, 2011 here you go, as promised, (sorry) taken with my phone. Since the subject was brought up, I felt that it may have some significance other than being a "fault" in the design. The lens is now in it's third generation and I think was originally designed and introduced before the advent of the digital m, ie., the M8. I feel the Perar has a generally retro look with very contemporary styling and finishing. The lens designer, Mr Miyazaki designed it just so, partly to imitate the compact nature of the original British Cooke lenses. My tiny Leica Elmar 3.5cm bears resemblances, particularly the diameter of the optics and m-mount which, as you can see, almost fully exposes the red 6-bit sensor. Undoubtedly the optics of the Perar have a much sharper and more contemporary, certainly less "glowy" rendering on a digital camera. Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/158826-perar-ii-lens-coding-for-m9/?do=findComment&comment=1806443'>More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.