Category Archives: Tools

Separation, leads to divorce, and a new coupling.

Sometimes you encounter a lens that has some internal blemishes that you cannot seem to clean off … can look like rainbow rings (ring of fire), a cloudy ring round the edge, a crescent beige tint, bubbles, or even a flowery/snowflake pattern … and it always seems like it’s trapped between two lens elements.

This old LTM lens has an almost complete ring haze. Now, it could possibly be just haze on the back of the element … but I suspected it was more than that.  After talking it apart it was apparent that it was separation of the front two elements.

Yes, in fact it is between two lens elements. Most lens designs require two lens elements to be bonded/cemented together (doublet) with adhesive to eliminate the glass air gap. By reducing exposed surfaces, cementing reduces refraction and ghost images from reflections, and allows the use of thinner flint elements. 

Older lenses used Canada Balsam as it had a high index of refraction, which is optically a good thing to have. It is derived from good ol Canadian trees … yup good ol sap … yes, its not just only for maple syrup.

Development of resins to cement elements started in 1785. Eventually changed to a synthetic resin because of WWII … high altitude aerial photography caused issues with Canada balsalm, so they developed a synthetic cement that could handle low and high temperatures … this is the MIL-A-3920 standard optical adhesive. UV curing adhesives appeared in 1966 to reduce the curing time for high production.

When the “cement” has degraded and no longer seals the two elements together, the separation will create artifacts that will change the refractive properties of the lens. Sometimes it is not very visually apparent … sometimes it is. The only real solution is to separate and re-cement them.

This topic has been discussed much on the web … FotomozaicLargeFormatForumskgrimes

With Canada balsam, it requires heating to soften the resin so the elements can be separated. The newer synthetic resins require special chemicals … and in some cases the elements cannot be separated without damaging it.

Once separated, new resin can be applied to cement the elements. Then new resin can be applied to cement the elements … modern day resins are UV cured, so makes it much quicker to get a lens back to working condition.

Sounds easy … not !!! Heating sometimes does not work, or even worse causes the element to crack … and there are cemented group that are encased in a metal sleeve which has to be removed first (without damaging the glass, and you may have to find something to replace it) … or, as mentioned before, it just doesn’t work.

One day I will make a serious attempt at re-cementing … meaning, my half-ass attempt sucked, and I will try again.

Summers Optical makes many different types of synthetic resins for optical cementing … and you can still buy Canada Balsam, as it is still used for microscopic slide mounting and painting.

Sometimes the lens separation is not so bad in terms of affecting the image, especially if it is around the edges like the lens pictured above … but when it sits right in the centre, it will most likely cause apparent visual effects. Mounting this lens on my Sony NEX-6 and taking some shots, I could not really notice it until I got some light hitting the front and the separation starts adding some flaring/fogging.

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There be knobs !!

There was one particular “tool” that I mentioned that could be one of the most important ones to have … or have access to … and that is a friend who has a machine shop.

I had completed the work on the Mamiya Six some time ago, but sadly the camera came to me with a missing part … one of the film spool supporters.

I thought, hmmm, possibly my awesome friend Craig could machine a new one for me … and that’s what he did.

The old one is on the right.

It’ not an exact replica, but I was not expecting that, just something similar.

Hey, it works … and looking almost like it’s original is a bonus !!


Some thoughts to start 2017 …

Oily oily oxen free …

Have you noticed I have not used any “oil” yet ?

I mention it in my section of tools.

I am not actually sure if any oil was used in the creation of cameras. Yes, there is the use of grease on many moving parts … especially on focus helicoids and the focus mechanism of TLR’s … but I don’t think oil is needed.

From the many discussions on the web … camera shutter mechanisms/gears are designed to run dry. Without access to the manufacturers service manual, you really do not want to guess what parts can be lubricated with oil, better safe than sorry.

If you add too much oil or the wrong type of oil, to escapements they can slow down … throwing off the timing of the shutter. If you add too much oil then it can leak onto the shutter and aperture blades … which is something you really do not want to gumm up.

I have used watch oil (though I never stated it) on heavy movement arms … but never anything close to the shutter, or apertures blades. When I do use it … it gets applied with something like a metal pin/needle.

Many of the cameras/lenses that I have encountered do have gummed up shutters or aperture blades. Most of the time is comes from old helicoid grease that degraded, liquified, and has leaked into the wrong places … sometimes it is just crud … and sometimes a DIY job.

 

Can’t get enough of that sugar crisp … or at least screwdrivers.

I am always needing screwdrivers. For some reason or another I tend to need one size/type that I don’t have … or is not exactly the right shape … length … etc. Now most of the drivers that I have are ordered online, since they are of very small point size I can’t get them easily … but recently I was at the local hardware store for something and noticed a cheap micro screwdriver set. It was the Home Depot brand, the Husky 8-in-1 Ratcheting Precision Screwdriver.

It comes with eight (yes, as the name says) reversable snap-on tips.

Slotted: 1.5 mm, 2.5 mm Philips: 0, 00, 000 Square: 0 TORX:T7, T15

After using this, I have found that I am using it half of the time … and the Torx is great when I am working on Laptops. The quality of the metal tips is pretty good, and you can get a good grip when necessary. The only thing I really have not used the ratchet, as I keep forgetting that it has that feature. They do make a version without the ratchet and added a twist top (handy for small thin drivers), but they did not have that at my location … and all for $9, yes less than 10 bucks (for you Americans it probaly means $5) !!!

 


Tools, tools, tool.

I frequently mention tools … because without them I could not do all this stuff. I am always encountering a situation when I think, crap I wish I had a <enter tool name here>. There will always be a time where you don’t have the best thing to do the job, so you make due, or you get the thing you need … or at least the closest thing.

One of the reasons the Yashica-MAT EM took so long was the seized screws and also some screws where the heads have been sheared off by a previous owner. The best way I could think of was to drill out the brass screws. I tried using my Dremel handheld … that didn’t work so well, as either I was moving too much and broke the bit or drilled out too much of the sides of the hole.

I needed a drill press. Well I looked and mini drill press’ are not easily found or cost too much … or where too big. Then I found that Dremel makes a Workstation. A drill press that I can attach my Dremel to.

I also bought a bunch of micro metal drill bits, a mini vise, and a mini tap and die set.

With the new tool I was able to deftly drill out the brass screws without damaging the threading !!


A word about support tools … broken stuff and a friend.

A friend of mine who has spent most of his life making and fixing things always collected broken/discarded parts to salvage for tiny screws, bolts, springs … etc.

He has shelves full of small containers and those organizer things, each with different pieces. This way he had a replacement for something … or a good enough replacement. I am always surprised when he can go over to one of the hundreds (and I am not kidding, I helped him pack/move them) of containers and find the thing he was looking for.

It’s also handy to have someone with decades of knowledge to ask.

Always good to get a hold of broken cameras of the type that you typically work on. Many use common sized screws and parts … and also other broken things with small parts.

Whenever I replace my computers (mostly laptops),the old ones are not worth it to resell, so I salvage the small parts from them. Some of these can be also be used for cameras.

One of the reason’s this Yashica repair took so long was the many missing screws (someone in the past tried to fix it) and the number of seized screws that broke while I was trying to remove them … which I needed to replace.

Whenever you can find a giveaway camera, take it … there probably is some thingamabob that you can use from it.


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