My particular journey into experimentation with lens modification started when I chanced upon an article form a blog by Yu-Lin Chan, a long time lens modder, on his blog – http://oldlenses.blogspot.sg/2015/04/a-gift-from-john.html. The article showed samples of images taken with an Aires Coral 45mm f1.9 lens from an Aires rangefinder camera which showed amazing rendition and bokeh – a lens character, if you will. Something which you would struggle to find in modern day lenses with their in camera image processed output.

Flash forward a few months later and my dad surprises me with a cache of cameras belonging to the family from my grandfather onwards. The choice items include a Yashica T4 and an Olympus Trip 35, both cult cameras, but sadly dead. This started me on my journey to see if I could salvage the lenses from compact cameras and rangefinders known to have good lenses and create a set of lightweight prime lenses I could carry around with me when travelling light.

This overview is particular to my experience and covers areas which I have explored so far, and that is very much based on the fact that I am a big advocate of 3D printing. There are other ways of modding such as gluing filter rings on to lenses and attaching them onto the camera using macro reversal adapters but that’s something I’ve tried… yet.

Why bother?

Let’s get one thing straight up front. Transplanting a lens which has been scientifically calibrated to perform on a dedicated, aligned and optimized to a specific camera is never going to yield as good a result as for the camera it was meant to serve. If you enter into this

However, given the right approach and care, a transplanted lens can yield results which produce interesting and rewarding results.

My experience to date has been mixed. In general, the transplanting of the lens and creating a mount and aperture for the lens has not been difficult. However, the performance of the transplanted lenses has been a bit of a mixed bag. The majority of the lenses I have transplanted have lived up to the expected performance in the center of the lens but not able to provide good edge definition.

As the title of this article suggests, this is a learning experience for me and one which I will document and share with those who are interested.

I have, to date managed to transplant over a dozen lenses and ended up with a whole lot of very usable pancake type lenses, mostly weighing under 100g, which I carry around with me to supplement my usual shooting set up and had a lot of fun along the way.

Types of lenses

There are probably technically accurate terms for these, but these are the 3 most common lens configurations I have encountered so far when extracting lenses from compact cameras and fixed lens rangefinders are:

ov_img_12Multiple lens groups, separated by an aperture and/or shutter – this configuration is the most common for fixed lens rangefinders and high end compact cameras. These lenses are the most challenging to modify as you will need to maintain register between the different lens groups, remove or modify the shutter/aperture and find a way of implementing an aperture between the lens groups.

Failure to maintain correct register and distance between the lens groups will result in aberrations and a distorted image. If you’ve ever used a lens such as the Lensbaby Composer or tried ‘lens bashing’, you will be familiar with the effects.

The next challenge will be to either remove or disable the shutter mechanism, leaving a clear light transmission path. In most cases, disabling the shutter mechanism by jamming the shutter wide open is the easiest way if you can locate the relevant part of the shutter mechanism. However, if your shutter mechanism does not work in the first place, then your only option is to remove it completely.

All this, bearing in mind that the next considerations – how to throttle light transmission via an aperture and allow the lens to focus.

ov_img_06Single lens block, usually sealed – this configuration is the easiest to transplant. Once extracted, the lens group is easily mounted. As these lens type is designed sit in front of their camera’s shutter/aperture mechanism, it’s also easy to create an aperture and focusing solution.

In some instances, the entire lens block, aperture and helicoid can be extracted as a single unit, making the transplanting of the lens even easier.

The only drawback is that image quality is not as great as the multi lens group with aperture in between. In my experience, some monoblock lenses are meant to be only shot wide open, with no aperture and using only shutter speed to control exposure. In these instances, adding an aperture mechanism has little effect on the depth of field, and can even cause vignetting.

There is no easy way of telling, you just need to try various options.

Multiple lens groups, floating lens elements, separated by an aperture/shutter – the floating elements in this configuration pose a serious challenge when transplanting recreating the focusing mechanism usually involves trying to replicate intricate mechanicals.

I’ve not tried to transplant such lenses, yet. My Olympus XA will remain in storage until I have a little more experience under my belt.

All the above configurations are based on compact cameras and rangefinders with fixed focal length lenses. I’ve tried to transplant zoom lenses from compact cameras but, with a couple of exception, they have not been successful. This will be covered in my future articles.

Mounting considerations

The object here would be to create a platform in which to mount the lens and, subsequently on to the camera.

In terms of creating a platform for the lens, there are 3 methods which I have tried to date:

Simple 3d printed mount –mounts lens block, simple add on aperture, attached to close focus helicoid. This is the simplest way of transplanting a lens, and works particularly well as a quick and easy way of transplanting lenses.

Complex 3d printed mount – mounts multiple lens groups, provides capability to integrate a separate aperture between the lens groups. This is the only way of transplanting a lens with multiple groups.

Donor lens, in which the existing lens elements are replaced with the lens elements to be transplanted.

Which method to use will be led by the construct of the lens and your options for creating a focusing and aperture solution to use on your particular camera.

In some ways, the camera you intend to use the lens on will dictate how you approach the mounting of the lens. If you shoot using mirrorless camera, there are more options including a lot of off the shelf focusing helicoids.ov_img_20

Focusing considerations

Perhaps the most important aspect for modding lenses is how you intend to implement a focusing mechanism. It is possible to shoot wide open, that is to say without an aperture, but if a lens does not focus easily and smoothly then it becomes a lot less pleasant to handle and use.

There are many ways of doing this and doing so successfully will lead to a lens which you will end up wanting to use, rather than one which you build for fun. The two methods I have tried to date are:

Use a close focusing helicoid – these are available in many mount options. The ones I would recommend for lens modding purposes are the Leica M lens mount to your camera mount helicoids if it exists, for the reasons I mention below.

3d printed helicoid, friction focus – this is a very crude way of focusing but is the quickest way for you to adjust distances between lens groups and establish the correct flange distance. It’s just a printed tube to mount lens elements which slides through hole in a printed mount. It’s not a long term solution, but I use this exclusively to determine the lens parameters before creating a more permanent mount to mount on to a focusing helicoid or donor lens shell.

There are other ways of creating a mechanism for focusing your lenses, such as screw thread focusing. This method is commonly used to focus images thrown from projectors. It’s not a method I’ve tried myself so far, but I am certain that I will be doing so in one or more of my future projects.

Lenses from compact cameras and fixed lens rangefinders are only designed to work in their intended cameras, their flange distance is often unique and poses challenges.

The primary reason why lens modification is more suited for mirrorless cameras is because of flange distances. Like the compact camera or or fixed lens rangefinder camera that the lens comes from, mirrorless cameras have a short flange distance. This makes it easier for the donor lens to be attached to a focusing mechanism. DSLR cameras have a longer flange distance to accommodate their mirror box, which makes modifying lenses for them difficult if not impossible.

The reason I recommended using Leica M mount focusing helicoids is because Leicas, being rangefinders, have a short flange distance. This allows for us to reasonably increase or decrease the flange distance for the donor lens by manufacturing a mount by recessing or protruding the lens. Additionally, the short flange distance also allows us to design built in apertures for the lens platform.

Aperture Considerations

When considering an aperture solution, there are a lot of options and most of them are straightforward to implement (corresponding images below, left to right):

3d printed fixed aperture plate – this is the simplest solution. It’s basically a plate with a fixed opening, which sits close to the last element in the lens

3dr party component aperture – these are standalone apertures which are manufactured specifically for scientific optical equipment.

Aperture from the camera the lens came from – in a lot of cases, the aperture from the camera the lens came from can be reused. However, in most cases, the apertures in compact cameras are controlled via internal linkages. The difficulty here would be in making an appropriate linkage to operate the aperture once transplanted.

ov_img_21

What’s next?

What I’ve written so far is only a guide to the thinking process involved in modifying and transplanting the optics from compact cameras and fixed lens rangefinders.

As an outline, the process I have found to work is as follows:

  1. Choose your camera, do not expect to salvage any parts. It’s possible but more often than not, the camera will end up being next to useless.
  2. Do your research – check for repair manuals/online repair guides, it will give you an idea of how to dismantle the camera, lens may not be worth extracting if the camera has a floating lens elements for example.
  3. Open the camera – avoid the capacitor, tape over exposed contact points.
  4. Extract lens
  5. Choose mounting, focusing and aperture approach
  6. Print necessary components in draft quality to check tolerances and fit
  7. Assemble the set up and make adjustments to the components
  8. Repeat until you have a satisfactory fit

The last 3 steps require a lot of perseverance and patience and I do not expect anyone reading this to be proficient just from reading this article.

If you are still interested in doing so yourself, keep visiting this site. I will be documenting the various projects I embark on.