[Sagitta]

Made this thing pretty much on a whim after promptly dropping the lens (denting it and causing a rattle) after taking it from its original box. I paid $10 for it as a gamble since the listing didn't have what brand it was for with the idea of reselling if it wasn't Pentax. I don't have infinity, but it works nice up close (and wide open, since I didn't bother mucking with the aperture mechanism).

I sacrificed an old Sears zoom I paid $8 for just so I could swap mounts.




And some of the resultant shots. A few seem tilt shifted since I didn't have the mount flush when I first cobbled it together.

[aliasant]

Has anyone converted Bronica S2 to Pentax?

I have bought a very nice and extremely sharp Nikkor-P 75mm f2.8 for Bronica.
I thought I would have more space between the Pentax and the lens and planned to use it on a bellows but that didnt quite work.

One idea I have been thinking about is to modify one of my M42 bellows so it is shorter by cutting perhaps half the bellow off. That should make it possible to get infinity.

Has anyone done or seen anything like this?

[aliasant]

I managed to put my Bronica on a Bellows and now it works from infinity to 1:1 or close to 1:1 at least. Havnt checked that yet.

I uploaded some pictures of it and from it here

[mikechopragant]

Anyone have any idea how I can get this lens off this cine cam without whatever tool was specifically made for that job?

[ovim]

Anyone have any idea how I can get this lens off this cine cam without whatever tool was specifically made for that job?

Pictures might help

[mikechopragant]

Pictures might help

Not sure why this photo didn't appear before

[aliasant]

Looks a bit like theres a lockring that needs to be unscrewed.
That metal ring between the lens and the camera body. Not sure what tool to use though. Do you care about the camera or are you prepared to slash it to get to the lens ?

[vanakaru]

try this tool
General Tool 452-6 6" Outside to Outside Measurement Caliper Legs

[ripit]

I don't suppose that anyone could give me an idea how to get the mount off this lens? It's a vivitar 70-150mm f3.8 close focusing auto zoom (serial 22???? so I assume kiron). The only info I have found is for other kirons but none are the same as this one. I have even found repair manuals for some but again, none seem to be the same as this one.

There are two pins on the rear of the mount (no screws), and 3 screws on the aperture ring (the stationary part above the collar that turns). There are also screws on the focusing collar.

I want to try and make a k mount for it (it is minolta sr). Fyi, yes I am aware of the issues with focal distance., If this lens is like any of the other kiron diagrams I saw, I suspect that if I just go tearing into it, I'll wind up trashing the lens. Can the mount even be removed without tearing the lens completely apart?

[mikechopragant]

Looks a bit like theres a lockring that needs to be unscrewed.
That metal ring between the lens and the camera body. Not sure what tool to use though. Do you care about the camera or are you prepared to slash it to get to the lens ?

It's a camera I picked up cheap in a charity shop recently, mostly because the lens interested me, so I don't have any particular emotional commitment to the camera nor do I imagine it's of particular value either financially or historically. It's standard 8. I have no projector and films are pricey so I doubt I'll ever want to use it for its intended purpose. Having said that, it's in pristine condition and is a complete kit, with filters and a carrying case and I have a natural inclination not to trash things like this unnecessarily. So I probably couldn't bring myself to destroy the camera to get the lens off. I'm also a bit unsure about how aperture is controlled. On the cine camera exposure seems to be controlled automatically by electronic adjustment of the aperture to suit conditions. I can't see a manual way of setting aperture which may mean it will be useless on a DSLR.

[rsBayArea]

Update on the old 1920's Schneider 30cm 5.5: it's been sitting on my desk at work for the last few months while I've been waiting for my back to recover from an injury so I can get downstairs on the lathe to machine a mount... I got impatient last week and decided that if I can't machine something pretty in a timely manner I would instead just make something that'll work. $3.00 of PVC at Lowes and my mount is complete.



The pvc initially gave me a washed out image, so I flocked the inside with an old black tee shirt rubber cemented in place and sharpied everywhere else I saw white. The effect this had on color contrast was mind blowing:



The bushing and flange put me just short of infinity (in the right direction- phew!), so I still have room to tilt and shift on distance shots. Focus goes from infinity to about 3.5 feet...



If someone could kindly describe to me how to calculate macro ratios I could probably come up with a pretty good number (I'm too tired to google it right now):



And, of course, the obligatory kitten portrait, flash photo, 125, f8, from about 15 feet away:



Whenever I get out the camera he starts posing, staring at the camera, rolling on his back, and he even tolerates the flashes without complaint. The perfect model.

This lens is a blast to shoot with and I'm looking forward to pushing it as far as I can. I feel lucky to have stumbled across this lens for only $15; when looking for info on it I keep finding them for $400-$500. It's my longest lens now so I'll have to take it on a field trip to a state park or preserve and see if it can catch birds as well as cats.

I also recently picked up a Kodak Anastigmatic Projection 105/4.5 enlarger lens. Holding it to the bellows, I could still get infinity focus (and the photos were sharp enough to cut steel), but unfortunately the threading on the rear of the lens is too close to 42mm to mount it to a screw body cap. It may end up on a pvc mount similar to the one on the 30cm but with a k mount end and some way to focus. How awful would a simple slip-fit sliding focus be to use? Guess I'll find out soon. This is, after all, just a hobby.

[aliasant]

Update on the old 1920's Schneider 30cm 5.5: it's been sitting on my desk.......

The pvc initially gave me a washed out image, so I flocked the inside with an old black tee shirt rubber cemented in place and sharpied everywhere else I saw white. The effect this had on color contrast was mind blowing:

Would be great to see a before and after shot or 2?

If someone could kindly describe to me how to calculate macro ratios I could probably come up with a pretty good number (I'm too tired to google it right now):

What you could do is simply photograph a ruler.
Macro 1:1 is when the photographed area is of the same size as your sensor.
Macro 1:2 is when the photographed area is twice as large as then sensor.

Your lens doesnt look to good as a macro but could work great for close focusing? I have seen similar on other old teles on bellows. Its great to get that close with them instead of having several meters as the closest distance. Similar to the Bronica I have a few posts up. The original would have a closest distance of about 75cm but on a bellows I get about 15cm and it still reaches infinity. I did notice that IQ dropped at higher magnifications though.

[rsBayArea]

Aliasant, thanks for the explanation. For comparison I shot with both the 300mm and my 50mm enlarger lens. Looked up the k2000 sensor size and the width is 0.925"; my 50mm shot measured .328125" (give or take...) and the 300mm measured 3.0625". This gives me about 1:0.35 for the 50mm and 1:3.3 for the 300mm. It just felt "macro" when a bee filled the viewfinder from 5 feet away, but I guess I'll be calling this lens "close focus"...

50mm:


300mm:

[ripit]

my conversions are on the simple side but I have gained enough experience I'm ready to try some harder ones. So far I got an olympus f.zuiko 50mm 1.8, a vivitar series 1 70-210mm 3.5 ver 2 converted from olympus to k mount, and a century optics .65X front mount teleconverter. The f.zuiko is wide open only. The vivitar series 1 has aperture control on the lens ring like a m42 lens but no camera connection. The century optics is a front mount teleconverter that originally cost about 600$. They sell for over 100$ used with a usable mount. I got mine for 20$ shipped with an obsolete bayonet mount that I converted to 52mm. The vivitar was only 15$ shipped from a new seller that listed it poorly (the ebay description was for the filter, not the lens).
Here is the century optics and the f.zuiko. I'll do the vivitar in another post since I just did it and have full pics.

[ripit]

On the vivitar I was going to use an m42-pk adapter but saw that it was bigger around than the hole in the lens (didn't stop to think that the mount was going to have to be pushed away from the lens and it didn't matter). I looked through lenses that I would be willing to sacrifice and found a working but heavily worn jcpenny 135mm 2.8 with 3 screws like the olympus mount had. The mount fit perfect. Of course then I realized it needed to be pushed away from the lens more.
A 52mm-49mm step ring did the job nicely as a spacer. I had to cut 3 notches for screw clearance. It focuses just past infinity (I can thin the step ring a little if I want to get it to stop at infinity).
Last problem was there was nothing holding the aperture ring down. A liner from a filter case fit perfectly after cutting a hole in the middle and thinning it down. The first one was too thick and was getting stretched over the grip groves in the aperture ring which caused it to split as seen in the pics. The new one (forgot to take a pic) looks just like the other one minus the split, and the thickness of the outer rim was thinned to about half. Its ghetto looking but I have some ideas to make the spacer look better (a step up ring might work well but I didn't have the right size). I would say a vivitar series 1 70-210mm 3.5 v2 for 19$ including the shipped cost of the lens and the donor lens but not the cost of the step ring isn't too bad.
here are pics from the vivitar.
http://www.pbase.com/richardh/series_1_70-210mm_v2
Next comes a minolta mount and a canon mount.