Xenotar 105 1:3 lens

Found one long forgotten lens in my camera chamber, this Xenotar 105/3 was BIN in xbay several years ago, at time I was charmed by Xenotar, any auction listed Xenotar would makes me click the page. 

This was listed by a gentleman from Germany, just front and rear element, no barrel, no shutter, as is, but in nearly brand new condition. I checked the web and found nothing on this lens, no the dimension of the thread, or any example photo made by it, but the hell, I grabbed it anyway.

Planned to adapt it onto a custom 6x9 or 6x12 camera, maybe the image circle is not enough for 6x12, then how about 6x11 or 6x10.5? I have some old six-20 cameras, there are in wider format, some frames measured at about 11cm at width, I thought that may be a good candidate for a pano folder.

But then I forgot it, since I don't know where to find a suitable barrel/ shutter for it, and that silver rim looks like a fly sauce won't let go, so I wrapped it and stored it deep in my dry box.

Today I took it out, unscrewed 3 tiny screws at side of front element, and helped by some gadget, finally I took off the sauce.

 glass is purely beautiful, thick and glued together, crystal clear, without any color, (meaning no coating??}

And then I measured the dimension of the thread, about 38mm in dimension for this part, but the front most glass which separated from this thick part is much larger, you can see them at lower left of the image below.

I did not take off the rear element, but manged to measure the dimension of thread, about 35mm. 

Well, does it mean now I can find a way to make it adapting onto some shutter, right? right? right!!!

Anyone has experience of this lens?

Xenotar 150 Gowlandflex on Nick

Only Xenotar 150/2.8 makes such bokeh. speechless...

I leave the original file (more than 40MB) here, you can download it to see pixel by pixel..... 

Xenotar 150 Gowlandflex

John Turner modified a Gowlandflex camera, made it both viewing and taking lens in Xenotar 150, what a combination!

Hey! this is what 4x5 snap camera supposed to do! a lively snaps!

He wrote to me about the modification,

"I decided to try to modify it to accept my underused Xenotar.  It required a great deal of work and modification. I found some recessed lensboards and adjusted parts so that when the frame meets the body...it is exactly at infinity.

Then bellows that go inside out and trimming the lens flange etc etc.
What did I get was a hand holdable..(although much bigger than a byron!)..easy to focus (used Maxwell focusing screen))(everything is bright) 4x5.The magnifying hood (homemade) with diopter for my eye, makes wide open focus easy!!"
"Dear John,

How envy am I now!!

This must be the most luxury Tlr 4x5 ever made! what do you think when bring it out and people get around you and WOW! maybe you can check their teeth at that time!

Xenotar lens is heavy and EXPENSIVE! so if I were you, I would try to find an enlarger lens, same as 150mm, to mount it as a focus lens, leave taking lens as Xenotar is more than enough.

What is the total weight of this tank? You must be very strong to hold it and snap on the street."

"Dear Daniel, It is easy to hold to shoot....its length allows your arms to rest at full length and you just need to tip your head a little.The shutter release is a pleasure as well!
The viewing lens need to match focus along its travel. The Schneider man told me that even between Xenotars you may not get a good match!  I bought a barrel with scratches for the viewing lens for 550! not too bad. It matches from less than a meter to infinity.
I will weigh it and let you know.  My negatives are tack sharp on the eye wide open 90%. 

I will try to send some to you...still don't understand Picasa!"

Months later, I received another mail with two huge images (33MB each), showing his camera does make great job!

"I took 12 pics... and 11 were tack in focus on the eyelashes...these are random...not the necessarily  the best of the group.  That is bamboo about 1 meter behind him."

Two original images had been downsizing to 1/64 in size, or this blog won't take it, but I crop the eyes which keeps in original size.

Folks, enjoy these beautiful images and great camera with me! 

Thank you John, you made wonderful camera, and such a lively portrait!!

Xenotar 135/3.5 on SL66

I dug my dehumidifier yesterday for my spared #2 shutter, and I found one long forgot Xenotar 135/3.5 sat there stared at me, I bought it last years, and then quickly shift my interest into big brother 150/2.8, this one left in the box till now.

It came as a barrel lens, with iris only, but I managed to fit it with a proper #1 shutter, and so there it can be mounted on Byron, or on my SL66.

This lens did not need extension tube, you can see bellows extends just about 1.5inch and you got infinity already, if you extend bellows to the end, focus can be as near as 1.5 feet.

Next time I will try to mount this beauty onto Byron, 135mm is quite wide for 4x5 snaps.

Xenotar Byron

Target for this month-- finish first batch of Xenotar Byron conversion, one for NY Jeff, one for myself..

To breaking the limits of original 110A/B front standard, to mount bigger size lens/shutter, I did try many ways to expand its ability, from beginning the target was to accept #0 shutter only, then by add additional spacer ring, now Byron accepts #1 shutter too, but due to the 'bottle neck' that spacer ring brings, some lens with big  rear element is limited.
Lens board study
150 Lens mount study

For even bigger lens like Xenotar 2.8/150, that mount on a #2 shutter (Yes! #2 shutter, not #3!!), I had to re-design whole front standard to take it. But at least initial test showed it is possible! see here:
Project I'm possible
The nearest distance Xenotar can get

Now, for a easier way to mount/un-mount this big eye, I need to develop another front standard/ lens board system, differ from the previous version.

They will be similar to normal view camera, with a somewhat rectangular lens board, and front standard will have a spring clip to lock the board.

The board, with maximun size of open hole to 60mm, Byron surely expands its lenses option, and since front standard extrudes a little bit, avoiding struts conflicting with shutter, so #2 shutter is possible too.

But the best thing this new system brings, is the opportunity to embrace 75mm wide angle lens without any difficulty. Previous version lens board takes 75mm too, but camera bed will block a little bit at one side, shading the image.
75mm lens on Byron

With new design, it may be no problem any more, but I need test first.

New system is specifically designed for big size lenses, it may not allow lens to stay in camera body when folded. I will try to keep the lens in, if lens board reverse the direction.

Oh, another minor thing, bellows needs new size too, for those big rear...

I got a Grandagon 4.5/75mm lens in #0 shutter, the one shown in image above,  a beauty.

New front standard/ lens board system plans to take this lens as wide angle end limit, not because front standard extruding or backward some distance, to avoid the blocking of camera bed, but by rising the lens a little bit.

It is about 7mm blocking on one side of frame, caused by lens backward too much thus camera bed shades the frame. It is no use to change lens board or front standard, because the distance requirement between lens and focal plane is fixed when focusing at infinity.

The only chance to avoid the blocking, is to rise the lens. 

I checked Grandagon data, it has 195mm image circle in f22, so there is plenty area to move.

Image above shows the reason one side of frame is blocked, 75mm lens is way too much backward, thus makes camera bed extruding and blocking the frame. On other LF camera like Technika, camera bed can be dropped a bit, to avoid the blocking, but Byron can not drop the bed.

Another way to solve the problem is by rising the lens a bit, makes less blocking area, thus eliminates the shading in negative area.

This way works in two conditions, 1. lens image circle is big enough for rising. 2. lens rises enough distance.

195mm image circle is big enough for rising, the only problem is how high can we  rise the lens?

In new front standard/ lens board system, front standard opening size is big, 61mm in diameter! Even bigger than previous version's lens board (60mm). images above shows that a #0 shutter should be able to rise no less than10mm, I believe it should solve the blocking problem.

But again, I need the test to approve it.

And why 61mm in dia. opening? Well, I want to directly mount the lens, and Grandagon 75 has a 60mm dia. rear, that is why.

(16/05 add)

Just back from factory, lens board spring clip parts are so small, and complicated, very difficult to assembly, and I don't like the effect, need to find a simpler way to hold the board......

(18/05 add....)

Had reduced spring clip into one part only, with spring(s), and bolts.
(To be continued..)