I was really touched by your enthusiastic response to the previous article. I really appreciate that.
Some person mailed me. It said that the content I showed in the first one had already been patented by some company. And I also confirmed that it’s true.
I should have considered that some maker had the thought while developing mirrorless cameras with short flange back.
There was a sad thing in some response. Even if it has already been patented, I could manufacture it if the level of the technology is like elementary school. It was weird.
I felt sad that the thought I’d been thinking became just a thing possible to illegally produce.
‘What have I done?’
“It’s easy to follow someone, but it’s difficult to do it first.”
I was in panic for some days. And I finally decided.
Let’s make a thing not patented.
The decision was simple, but actually it’s very complicated. As I found out in the MF lens adaptor of the mirrorless cameras, they don’t even use the patent for real products in many cases.
And it’s also very difficult to follow the technology, if it has no patent. I also had to produce, not just find the technology, so I was worried about it more.
However, it’s fun to do a thing difficult.
If everything is easy, it will be really boring.
Therefore, the theme of this test is “Creating TS (Tilt & Shift) lens working as AF for mirrorless interchangeable lens cameras.”. Let’s see what the TS means first.
– Wiki Attach –
TS is a shooting method usually used for large cameras. Refer to the drawing.
Picture  and  is a image focused on a normal lens.
It’s a drawing of my first article. However, when it comes to these normal lenses, there’s some distortion of the subject when taking a big subject like a building from the down side, due to the slant between the sensor and film.
In order correct this distortion, like the , the correction method by moving the lens up and down is called Shift, and if a lens has this function, it’s called a Shift lens. Tilting the optical axis to correct the distortion is called Tilt. This lens is Tilt lens. And we call them together as TS lens.
The previous purpose of Tilt/Shift was for building, but recently, it has also been used for landscape, miniature, and so on for making forced distortion.
Does the picture look like a miniature? It’s the driver’s license test course taken with Tilt/Shift.
We’ve finished learning it, so let’s make the TS lens.
Now, let’s proceed it with the bundle lens 18-55mm
Part which light can go through
Like the previous article, I disassembled the mount. I just disassembled the mount, but there was some serious problem.
The aperture is optimized to F3.5-5.6, so except the space of eye part, it’s covered with board. As a result, light accepting part is too narrow, so it might hide the part of light. Let’s check out the solution later and finish the rest.
It’s just a simple disassembling.
Let’s focus on aperture + AF module + OIS module
When it comes to OIS (Optical Image Stabilization) module, it’s composed from very early stage of the first design and very sensitive. Therefore, I don’t think it’s possible to disassemble and upgrade it, because it moves 4 coils with 8 contacts to the direction of hand shake. I gave up and took out the contacts.
It uses stepping motor for AF operation. Unlike a general motor, a stepping motor has a RPM control module, so the RPM of the motor can be controlled by 1/2 RPM or 1/3 RPM. Additionally, compared to DC motor using spur gear to reduce the RPM and needing a sensor calculating the reduce RPM, it takes a less space.
However, for this reason, it has weaker output than DC motor. It’s not appropriate to be used for AF module, unless the lens design is IF. But the bundle lens design is IF.
As you may have already known, an AF module consisting of stepping motor can’t be used for this modification to move the whole lens.
However, I already mentioned ‘it’s fun to do a thing difficult.’, ‘If everything is easy, it will be really boring.’, so I can’t give up now, right?
In this modification, I keep trying to use the bundle lens.
But the stepping motor in the bundle lens is a linear stepping motor, so I replace it to a stepping motor with a larger output.
Like you see, it works properly after the replacement.
It’s the lens used for the modification
Carl Zeizz Distagon 28mm F2.8 (Assumed)
Every time I see this lens, I want to modify something. The previous trial MF lens to AF lens was with this lens.
It has a relatively smaller size than other lenses. It’s small, but it’s made of metal and glass, so it’s not that light. Therefore, we need something making it move more freely back and forth. It also has to change the straight line motion to circular motion, and error in the moment has to be small.
Where should I get this thing satisfying everything? Amazingly, I’ve found CD-ROM drive.
Disassembling a CD ROM drive, there’s a gear part moving the LASER detector back and forth. It looks possible to me. I would try with this one.
Except the straight line motion and gear, take all the parts.
It’s a normal Ball clip. Its principle is similar to a ball head.
Fix this clip to the lens by using Magic Fix. (Epoxy adhesive)
Once it’s stiffened, it becomes like reinforced plastic. Additionally, the grey product has a similar thermal expansion to a metal, it’s perfect for metal.
Fix it to the rotation part of the CD-ROM.
Because the bundle lens has a plastic mount, I put a screw to fix the camera.
I’ve solved the problem hiding light by connecting the wire and keeping away the board. As you can see from the picture, I hid it under the CD-ROM.
It’s a mount. It looks everything gathered, but one important thing is missing. It’s bellows to hide light.
Let’s make a bellows, too.
Draw the diagram on a thick paper.
Cut them (With a pre-determined interval and try not to cut the part of the paper on lines.)
Put them on reformed sticker made of synthetic rubber with a certain interval (The papers have to be put like the picture like a zigzag with one line difference.)
Cut the reformed sticker and put tape between the papers.
And fold them. It’s the finished one.
I tested it without the bellows to see the operating better.
It worked properly.
I could also tilt the lens back, forth, up, and down without engaging forces. There was no problem to get the AF (Refer to the previous article to see the operation principle.)
Because a stepping motor was applied for the AF, I needed to move the lens and set a approximate focus, and then it sets the accurate AF by having the motor moved.
I took sample shots.
It’s the roof taken from another roof. It really looks like a miniature.
It’s between buildings taken from roof. I’m sure that it’s almost impossible to make this effect even with PhotoShop Lens blur effect.
Isn’t wondering that pictures are taken like a miniature? It ca
Taking a driver in F2.8, how does it look like?
It will be like one of them above, right? However, using tilting
The picture will be like this with right focus.
It looks weird, but I’m relieved that I could see the finished one.
I’m just a University student majoring in Computer engineering. I can’t actually design mount, get an high quality parts, or create a perfect product.
Please don’t laugh at how it looks. As I’m aware of, ‘With a lens for small camera, making TS function work” has not been patented yet.
In this article, I’d like to tell you that it’s possible to create TS converter using the gain from shot flange back of the mirrorless interchangeable lens camera.
I hope more lenses will be released for those who enjoy taking pictures.