markruskikh

Dear community, I own a mamiya 127mm K/L lens. The lens has a “foggy” rare lens doublet. Which I recently learned is quite common on this particular lens. Most listing on eBay rated at near mint/exc5 or even mint have this problem (which is for another discussion as rating of lenses especially by Japanese sellers over the years have degraded significantly.) many people use this lenses with that condition as is, which is doable, and somewhat gives you a soft focus 127mm lens if you watch out for high contrast scenes, or during long exposure night photography you will get results somewhat similar to the look of cinestil 800t. Which I do not like (for my style the more sharp the image is the better, even for portraiture.) after consulting with photo repair stores, optics labs, and even some of my scientist friends who work in the field of optics I learned that no one will take my oldy MF mamiya glass and take apart the doublet re-align and recement it. I was told that the price for the job is just many times higher than the price of the lens. so here comes the fun part. I decided to do it myself. As I really have no use for a soft 127mm. Now the doublet is being soaked In methylene chloride and soon will be ready for re-cementing. the question is does anyone know what kind of optical adhesive was used in mamiya k/l glass? I assume it’s a synthetic cement or UV cured epoxy adhesive as it did not look like Canadian balsam or something of older types adhesives. The most important question is does anyone know the refractive index of the used adhesive? So I can chose a replacement accordingly. best regards, mark

thank you for your post, I’ve taken the lens apart and the worst fear turned true, the problem is in between the two cemented elements in the rare double.

did few more rolls rated at box speed and scanned at different labs, and flare was consistent throughout all.

Dear all, Little update on the issue. the rare element of my lens seems fogged (pictures attached). Not very noticeable looking through the lens however when using a flashlight the whole rare element glows beyond any kind of transparency. I’ve got mixed feedback from my local camera repair stores, some said fungus, some said haze- which I tend to agree more with as it was my initial assessment as well. The only thing I fear if it is lens separation as I have no idea how to fix that. anyways, all of them refused to service a lens with anything like this, I guess in Brussels it doesn’t go beyond cleaning dust. So I’m waiting for the lens spanner wrench to come from Amazon and will dig in the rare element with some ammonia and hydrogen peroxide being handy. let me know if anyone dealt with the same issue.

it does seem like there is a thin layer of haze in the back lens element internally. Wasn’t aware that it can cause such a dramatic effect in high contrast scenes. Will have my Lens serviced. Thank you.

Dear all, I’ve recently got scans back from the lab, and I have some halation around highlights in high contrast scenes. See attached. can someone tell me what can be causing it and how to reduce it? photos were shot with Mamiya Rb67 pro SD, and a 127mm K/L lens. With portra 400, rated at 200. The day photo was shot at about f11, and the night one is almost wide open f5.6 as I wanted to avoid cars getting in the frame hence faster shutter speed.