Project 02 – Olympus Mju II

Project 02 – Olympus Mju II

One of the most popular cameras of the 1990s, it is a modern classic – an affordable, stylish, light, small, splash proof camera with a fast and sharp lens coupled with accurate AF. There’s almost no downside to the camera and it is no wonder that Olympus sold almost 4m of this particular model worldwide.

It is one of the cameras I was most excited to modify to fit on my digital cameras. The process itself, however, was far from easy and involved many iterations of the final version of the adapter which I am showcasing here. The challenges were mainly to do with the extraction of the lens unit and then the designing of the adapter which would articulate the shutter/exposure mechanism which is conveniently integrated within the lens assembly unit – which can be extracted (with difficulty) as a single unit. More information can be found in the appropriate project areas.

Lens: 35mm, f/2.8, focusing from 0.35m-infinity. (4 elements in 4 groups)

Optical system construction: Lens is encased in an extended mono block plastic cylinder with 4 lugs which hold the lens block in place on a focusing platform. Also attached to the unit is a combination aperture and shutter mechanism.

Shutter and Aperture: Combined Shutter/Aperture mechanism, single set of 3 blades. Iris is a non linear triangle shape.

Common Failures:

  1. Battery door failure – very common and replaceable, unless the surrounding area where the door is mounted is also damaged (also common). Tape is crude and effective way to cure this but, inevitably, this is one of the most common source for cheap Mjus on sale on eBay
  2. Film Transport/micro switch failures: many symptoms for this, ranging from total failure in transport operability, to partial failure with some forms of film transport and flash failure. The latter is caused by the micro switch failure which syncs shutter to flash operations. Both are interlinked and made mainly out of plastic, which has a tendency to fail. Transport mechanism failures can be fixed using gearing from a donor camera but micro switch failures are almost impossible to fix.

Lens Removal:

This is guide on how to remove the lens out of a Olympus Mju II. It is NOT a repair manual. All the cameras I extract lenses from are beyond repair and my method of removing lenses is based on the easiest way of removing the lens at the expense of the donor camera.

The Olympus Mju II is a very densely packed camera, it’s compact form factor means that everything is very tightly packed into the compact body.

disassemble_1Step 1 – Separate the front and back clamshell 

The Olympus Mju II is a splash proof camera and front and rear clamshells are designed to keep moisture out of the camera. The first step is to separate these two by popping open the rear film chamber door and removing the screws highlighted in orange

Step 2 – It gets ugly, you get creative

See a screw, remove a screw. That is the basic idea. The good news is that most of the parts are plastic so where there is resistance, its relatively easy to break the bits that stand in the way to you getting to lens. There is no way of extracting the lens without sacrificing the camera in entirety, be very clear about this. It’s not a case of being careful, some of the parts in the camera are welded together and can only be forcefully separated, with no chance of reassembly.

The Prize. The extracted lens unit is approximately 24mm at it’s widest (not including the lens mounting lugs) and 25 mm high.

The rear of the lens. Note the large and bulbous rear element (compared to the front). This throws light at acute angles towards the edges.

Rear, the aperture/shutter wide open. Actuation of the aperture/shutter is via a tab in the bottom right of the lens unit.

 

Aperture/shutter closed down approximately half way. Note the triangular aperture. The aperture/shutter will close down completely when fully articulated.

Method of conversion:

  • Complex 3d printed mount in two parts, secured with a screw
  • Lens mounted between base of the mount and secondary enclosure
  • Base unit  has prongs to articulate shutter/aperture blades
  • Mount coupled to Leica M mount close focus helicoid

The adapter mount consists of two pieces – a base unit and a lens mount, which also has a handle to articulate the lens unit’s aperture/shutter mechanism

The lens unit mounts onto the lens mount piece by friction fit. It will be farther secured when attached to the base unit which has a lip to prevent the lens and mount units from travelling

 

The lens and lens mount unit is attached to the base unit. The base unit has a pair of prongs to articulate the shutter/aperture mechanism

The base unit has a slit to allow for the articulation of the shutter/aperture mechanism

 

The anchor screw attaches to the lens mount unit via a point which is printed in the lens mount unit. Here, I’m showing the mounting point without the outer base unit attached.

The final, assembled adapter, with both units attached. The lever on the bottom left is used to articulate the shutter/aperture mechanism.

Sample Images

Sony A7M2, 35mm f3.5, 1/3200th sec, ISO 100
Sony NEX-6, 35mm f3.5, 1/200th sec, ISO 100
Sony A7M2, 35mm f3.5, 1/250th sec, ISO 100

Some initial photos taken with the lens, full resolution versions and more photos taken with the lens can be found in on my Flickr album

Results and Conclusion:

The Mju II is the first real disappointment I’ve had so far (I’m sure that there will be more) in my efforts to convert compact camera lenses to work on digital cameras.

As you can see, the results from the images I have used to summarise the lens performance, the images are tack sharp in the centre but this sharpness rapidly disappears towards the edges. Additionally, closing the aperture/shutter blades does little to increase the depth of field of the image captured or increase edge sharpness.

The main culprit for this is the, bulbous, wide rear element which spreads the image from the lens across the size of a 35mm frame. The flange distance between this element and the film plane is very small – approx 9 millimetres. The last element in the lens group does this by distributing light onto the film plane at very acute angles. Fine if it the final capturing medium is film, not so good if the capturing is being done by a digital sensor with a (relatively) thick piece of glass in front of it. The results are a distinctively smeared image and there’s nothing that can be done about it.

It’s a major disappointment as this is undoubtedly a very sharp and fast lens. Being able to utilise this on digital cameras would have been a major achievement. As it stands, I cannot recommend that you try to convert this lens for any practical purpose. The narrow flange distance and rear lens element characteristics mean that you will never be able to overcome the edge performance characteristics with the current digital sensor technology.

Additionally, the 9mm gap means that the converted lens will not mount on most APS-C sensor cameras as most of them have a blanking plate around the sensor which will prevent mounting of the lens. The lens (with enclosure) diameter is wider than an APS-C sensor so it will only mount on a full frame sensor camera.

Having said that, I learnt a lot converting this lens and look forward to seeing how it can potentially perform on my M mount film cameras, using hyperfocal focusing. Watch this space, as they say.

Flikr Groups:

https://www.flickr.com/groups/659149@N23/

Camera Review links:

http://www.35mmc.com/05/06/2013/yashica-t5-the-path-to-enlightenment-part-1/

Project 01 – Yashica T4

Project 01 – Yashica T4

Cult camera with a reputation for sharp lens and unique rendering, made famous by fashion and portrait photographer Terry Richardson. This is a compact camera of repute and many many articles have been written about it. There are a few links at the bottom of this article if you are not familiar with it. I’d like to focus this article on the lens conversion aspects.

My particular copy belonged to my father and came with a stuck shutter. Destined for the bin I decided to see if I could salvage it. The following project documents my efforts to do so. I have a compulsion fettle so, there will be updates to this article as I go through variations.

Lens: Carl Zeiss Tessar 35mm, f/3.5 lens, 4 elements in 3 groups, T* (multicoated)

Optical system construction: Lens is encased in a mono block plastic cylinder with 3 lugs which hold the lens block in place on a focusing platform. Also attached to the focusing platform is the combination aperture and shutter mechanism.

Shutter and Aperture: Combined Shutter/Aperture mechanism, single set of blades

Common Failures:

  1. Shutter failure – replaceable with donor shutter cable
  2. Motor drive failures: motor not working (replaceable with donor motor), motor not advancing full frame (often it’s a logic board problem and non economical to repair)

Lens Removal:

This is guide on how to remove the lens out of a Yashica T4. It is NOT a repair manual. All the cameras I extract lenses from are beyond repair and my method of removing lenses is based on the easiest way of removing the lens at the expense of the donor camera.

It is fairly straightforward to remove the lens off the Yashica T4. All you have to do is remove the bezel, remove 3 screws and extract the lens. Whilst this appears to be a non destructive, the lens is mounted immediately in front of the shutter mechanism; which is a known area of weakness. Damaging the shutter mechanism is a risk of removal. The bezel itself is held on by 3 prongs on to the focusing platform. These prongs are extremely fragile and may not survive the removal process. However, this is not necessarily a bad thing as, if you intend to follow on by modding the lens, you can use the bezel as a protector and lens hood.

guide_img_15Step 1 – Expose the lens

Insert battery into the camera and turn it on. The lens protector should slide down and expose the lens bezel and lens. If you are unable to power on your camera, you can manually slide the lens protector downwards and out of the way. However, the lens and bezel will be recessed into the body and it may be difficult to remove the bezel. If you have any difficulties, refer to the addendum of this guide and remove the camera casing.

guide_img_17Step 2 – Remove bezel

Once exposed, place a small screwdriver at the 12 o’clock position of the lens and apply gradual pressure to the bezel until the retaining prong releases from it’s socket. Repeat the process at the 4 and 8 o’clock positions until you remove the bezel.

guide_img_13-1Step 3 – Remove lens

With the bezel removed, all you have to do is remove 3 screws to remove the lens itself.

 

The extracted lens is approximately 20mm at it’s widest (not including the lens mounting lugs) and 12 mm high. It’s Zeiss T* coated and comprises of 4 elements in 3 groups

Addendum

If you have problems extracting the lens, you may still access it by removing the camera’s outer casing.

guide_img_01-2

Remove two screws on the right side of the camera as indicated.

 

guide_img_02-1

Next, remove 2 screws from the bottom of the camera.

Finally, remove the 3 screws within the film chamber.

The Yashica T4 is weather sealed so it is not easy to pry the front and rear casing apart but it is possible.

 

Method of conversion:

  • Simple 3d printed mount with lug for printed aperture plates
  • Lens mounted behind the base of the mount
  • 3D printed fixed aperture
  • Mount coupled to Leica M mount close focus helicoid
guide_img_07

Rear of mount with lens in place

 

guide_img_05

Rear of mount with aperture plate in place

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Front of lens with lens and bezel in place

Sample Images

Sony A7M2, 35mm f3.5, 1/3200th sec, ISO 100
Sony NEX-6, 35mm f3.5, 1/200th sec, ISO 100
Sony A7M2, 35mm f3.5, 1/250th sec, ISO 100
Lens Modding Overview

Lens Modding Overview

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.