Project Impossible--Byron Version

I just said that "don't even think about it!!" at 150mm lens test, about Xenotar 2.8. Then Jeff that New Yoker really good at persuasion, whispered: "If you made it, you will be the first and the only one who brings Xenotar to snaps, think about it!"

................

That really tempts.

Well, think it twice, its nearly impossible.

nearly.

(to be continued)

Multi Infinity Stops Engraving

Each Byron is converted by clients' requests, especially for the lenses they picked. Different combinations of brands and types of lens, shutters, it definitely needs each lens' infinity stop be measured specifically.
After individual measurement for each lens, then the i.stop engraving work needs help by my mechanist.
First, a special T type lathe knife was ordered.

The knife will engrave the plate a 1 mm width ditch, to keep and hold the front standard on location. Measurements are precisely down to 0.01mm, and with a CNC lathe machine, that will do the job very well.
Secondary, my mechanist made a fixture tooling, to hold the plate in fixed position.

Fixture tool firmly holds the plate in vertical position, and knife lathes tiny ditch according to the measurements.

Then the plate is engraved the digits of focal length by the side of ditch, for identification. I need some more practice of engraving......

For my own reason, to ensure pairing the plate with matched camera body, I engraved each owner's name on the back of the plate.

Then the installation, and rechecked the focus. Noticed that 90mm lens distance scale at the right side? that is for un-coupled focus.

Lens mount study---150mm lenses

Each lens on Byron needs to be measured for its infinity stop, that is why I asked my clients to ship their lenses planning to use on Byron to me.
Byron is handmade converted, and the lenses are in different shutters, these variations bring great differences within lenses in same focal length.
Recently I measured 12 Byrons for their 4.7/127 Ysarex, to engrave their infinity stops. I found out that i.stop location changes within 4mm range, specific camera should paired with specific lens, no lens/camera switches allowed.
And on 150mm lens, I got 7 lenses this time, all in different type, although they are marked 150mm, but by their i.stop location, I'm sure some lenses are far less than 150mm.

Another BIG brother is a 2.8/150 Xenotar, I put a 127 Ysarex with it as comparison, you can see its size!! In  #3 shutter! Jesus Christ!

We will discuss each lens one by one, for future references.

Rodenstock Geronar 6.3/150 in #0 shutter

This lens got the shortest i.stop distance among other 150 lens, I doubt it is far less than 150mm, but found no data to prove it.
It doesn't need extruding lens board, normal board is good enough, and best of all, this lens can stay in camera when fold up, its tiny size and light-weight feature is great for travel and pack-carry, all these make this lens highly recommended for Byron.

Voigtlander Heliar 4.5/15cm in #1 shutter

This vintage lens is rather fast--4.5, and needs a extruding lens board, for its exceeding i.stop, and for its #1 shutter.

Fujinon.W 5.6/150 in #0 shutter--older version

Fuji 150 lens on normal lens board, can be directly mounted on, that is, no need to unscrew the rare element first. Compared with newer version, this lens is rather small in size, and quite easily mount/unmount.

CM Fujinon.W 5.6/150 in #0 shutter--New Version

I don't understand why Fuji made this version in such a big size, much bigger then previous version, but the lens are all in same size, a lot of space is wasted on its "bowl", front and rare, brings troubles when mounting on Byron.

two versions compared in size.

Infinity stop moves further a little bit, compared with old version, so it needs an extruding lens board. And the rare element is bigger than 48mm in diameter, must be taken off when mounting, then re-screw it on, that makes this lens the least choice for Byron, take my word, choose that old version.

Schneider APO Symmar 5.6/150 in #0 shutter

I was hoping to mount this lens directly, according its rear size in 47mm dia. smaller than Byron front standard lens hole 48mm, but because of extruding lens board, it only allow for in-directly mounting, very disappointed.
So there are two options:

1. installed with extruding lens board, and in-directly mount the lens.

2. installed with normal lens board, directly mount the lens, but rail extends about 2mm.

I will take option 2, for 2mm of rail movement loss cause focus range from 5 feet to about 5.3 feet, and I think I seldom to use a 150 in such close distance.
Pity, this is my favorite lens, but I can't make it perfect fit on Byron.

Fujinar 6/3/15cm vintage lens in #0 shutter

This tiny lens takes extruding lens board for its 3mm exceeding i.stop, other than that, no problem on mounting/un-mounting, very light-weight, a great lens for travel and trekking, but front element is little bit high, preventing it staying in camera when fold up.
Seikosha-Rapid shutter got a funny long release arm, so it can be released by Byron's sliding release, another weird plus.

Rodenstock APO Ronar 9/150 in #0 shutter

This lens takes extruding lens board, it is tiny, light-weight, easy to mount/un-mount, and very sharp. Though it is not a fast lens, but you can pick it in very reasonable price, and thinking of we always take pictures in rather slower aperture, like f/11or f/16, it is actually a good candidate for rangefolders.
(to be continued.....)

150mm lenses Recommendation List to fit Byron:  

Best!
tiny, light weight and stay in fold up
1. Rodenstock Geronar 6.3/150mm

Better.

directly mount, take off when fold up

1. Fujinon.W 5.6/150 (old version)
2. Fujinar 6.3/15cm
3. Voigtlander 4.5/15cm (in #1 shutter)
4. Rodenstock APO Ronar 9/150

Better NOT!!

indirectly mount, take off when fold up

1. Fujinon.W 5.6/150 (new version)
2. Schneider APO Symmar 5.6/150

Don't Even Think About It!!

1. Xenotar 2.8/150 in #3 shutter

Lens board study--#1 shutter available for Byron now!

110B camera was designed for 127mm lens, it's flat bed has 20mm of rail moving range, enough for 127 lens to focus from infinity to 3 feet.

Now we are planning to use 150mm lens on it, 20mm range just makes150 lens focusing from infinity to 5 feet, I tried to extend the moving range flat bed, but fail, because the arm connecting the lens cam is not able to extend any longer.

That makes 20mm rail very precious, we should utilize all the range on focusing purpose.

When lens focuses at infinity, it gets shortest distance from lens to focal plane, and then distance added when focusing near objects. So we need at least locate the i.stop position for 150mm lens on flat bed, then utilize the rail movement for object within range.

But the bed is so long to accommodate all 150mm lenses' i.stop, some 150 need little more extension for infinity stop. Previous post has discussed about this situation before. (We will discuss about variety of 150mm lenses later).

Images below shows some i.stop for 150 needs no extension, but some need about 4mm of extension to achieve the shortest distance.

4mm of rail movement for i.stop, means that focus range will be shrinked from 5 feet to maybe 6 feet, which is, definitely not tolerated.

The solution? we should try to make 4mm extrudes of the lens when mounted, so to keep the precious full 20mm rail movement on focusing.

So here is the answer, besides normal lens board, there are extruding version.

That complicates the parts we need, but it worth it, because not only it solve the 150mm lens problem, it also allows us to use #1 shutter on Byron.

Extruding ring makes #1 shutter avoiding the collision with struts. Next time I will try my Angulon 6.8/120 on Byron!!

Image below shows Heliar 4.5/15cm lens on Linhof #1 shutter, from Prof. Don, when the lens arrived I measure the shutter, it is OK to mount on normal lens board, but struts on both sides makes operation awkward, but now with this extruding lens board, not only solves the i.stop location problem, also makes this big shutter operates easily and cozy.

Do you see it? Don?

New Year, New Shoe, New press button

That bothers me, so I face it and solve it.

The cold shoe, was bought from HK, I took it apart and installed it on Byron with a custom base. It looks like this:

Thought that would be a nice solution to convert original shoe into a international standard size, so I order some from HK again, and made the base in small quantity.

But then I realized that these "made in China" products are unstable in size, some are too tight for mounting, some are OK and some too loose, that bothers me, a lot!

Rather than being complained by my clients, I prefer to face it in advance.

So all these cold shoes and bases are abandoned, I ask my mechanist to make a new one for me.

Byron need only one screw to fix, the second hole is designed for Emily, I planed to implant two or three shoe mounts on her, three in a row! You can install a view finder, a range finder, and a level or a flash at the same time!

Borrowing from lens board, luckily I don't have to order new custom size of stop fixer screws,

Now the shoe is made in one piece.

But for those accessories doesn't have a locking screw, this shoe is little loose to them. I asked the price to order a tiny spring plate for shoe, but gave up of the cost.

So to mount an accessory that without locking-screw, and seems loose, you can:

1. insert a little piece of paper in the shoe, then insert the accessory.
2. use Scotch 3M tape, paste a little piece in the shoe.
3. insert a transfer shoe mount first, then insert your view finder

So the only one part I bought from ready-made, is the 3/8 to 1/4 tripod socket.

People tells me that they rarely use 3/8 tripod anymore, no need for an adapter. Well, I am kind of old fashion, alway keep the option.

Oh, by the way, I add a little rubber button for the shutter release, because days before a lady who loves to take pictures operated Byron, and she couldn't find the release, finally she found it, and she said that the release is not handy for a girl with little palm size like her, better if she didn't have to press it so deep.

Storing Chamber

Just found out that I never post images of storing chamber, so here they are:

Shutter release and lens cloth can be stored in the chamber,  door closed tightly, controlled by a tiny screw just under the eye cup (a silver shinny one), can be adjusted if you feel it too tight or loose.

Emily has new covering and bellows

Emily with a Grafmatic film back, Looks nice and neat. But she needs a new lens board