Thursday, August 19, 2010

Welcome to Xenotar club

One goes to NY, one goes to Texas, one goes to Germany. 6 of Xenotar lenses this batch, next 3 will be on 2 weeks later.

This summer class is the most difficult one I ever met! Too hot to do the conversion, and all kind of challenges jumps out during the job, from places you never think of, take bellows as example, I made about 6 bellows prototype, and modified blue print 16 times, finally grabbed the key.

Then the front standard, factory went wrong on dimension FOUR times! can you imagine?! It is damn too hot!

Not yet mounting the RF housing, tonight's job.
Look carefully, the left one is a little bit small size on bellows, will replace it after shooting.

Tuesday, August 3, 2010

Bellows, bellows....

Bellows was re-sized for Xenotar 150, thinking that no matter the extension length or front opening size, is perfect fit to Big Eyes.

Mounting Xenotar 150 is an in-direct procedure, rear element needs to be taken off before front element/shutter mounted, then screw back the rear element.

I keep the bellows in no extension situation when screwing back the rear element, then the problem comes. Bellows is so perfect fit to the lens, the front opening size is just slightly bigger than rear element, so when I screwed the rear in no extension situation, some folds in front of the bellows were clipped, that is Ok since bellows has enough folds for rail movement, but it looks awful. Folds will not be clipped if you screwing the rear when bellows extended in half or full length, but that makes a deep hole and brings difficulty for screwing.

Solution? re-size the bellows, make front opening size even bigger, so no folds were clipped when bellows in no extension situation.

Byron got three version of bellows sizes now, Khaki color shows opening for #0 shutter lens, Blue opening shows the size for any other lenses other than Xenotar 150, and the Gray one shows the opening size exclusively for Xenotar 150, the Big Eyes.

All three sizes are bigger than 110B's original bellows.

And the RF parts was sent for fine tuning, for this lens, mechanist told me he needs to take part all RF parts, we will wait and see.

Before it came back, I made Byron as a simple view camera, and test the stability. Lens is heavy, but front standard works well. Without RF viewing windows, and my model keeps moving on chair, it is hard to capture him and the little tree he planted.
No folds are clipped if rear element is mounted when bellows extension in full length, but rather hard to do, and you can see one front side ridge of bellows were bumped..., reasons for re-sizing a bigger bellows is obviously clear.
Film expired? no matter developing time I changed, saturation is way less than what I saw.