[tuco]

The image has nice tonal scale. But that looks like a light leak and/or uneven development.

[Swift1]

The 90mm has a cable release socket on the lens to trip the leaf shutter as well as manually doing it with the S-U lever on the lens.

IIRC, it only works properly if the stop down lever/pin in the lens mount is actuated. The way it would be when mounted and with focal plane shutter open. This mechanisn closes the leaf shutter.

[wombat2go]

The image has nice tonal scale. But that looks like a light leak and/or uneven development.

That was due to me having to turn the light on after I failed to start the spiral.
That was the only frame that partly survived.

[tuco]

IIRC, it only works properly if the stop down lever/pin in the lens mount is actuated. The way it would be when mounted and with focal plane shutter open. This mechanisn closes the leaf shutter.

Yeah, it still needs a way of moving the lens's aperture lever when not mounted on a Pentax body (tape it, I suppose). But the leaf shutter is pretty independent. I'm able to trip the LS on my 90mm while only holding it in my hands while not on the camera.

---

Last edited by tuco; 11-10-2012 at 10:13 AM.

[klaus123]

How about using enlarging lens like the Schneider Componon or Rodenstock .... with some luck you can get them cheap in several focal lengths

[wombat2go]

Hi Klaus,
I adapted a 90 mm Rodenstock Omagaron to M43 using the Pentax Bellows -M and a Leica M39 adaptor made on the lathe
It works OK , but I think it needs a hood for sunny 16 days.
This adaption is not possible to a pentax slr/dslr due to their longer register.
This lens should adapt well to the 6 by 9 format and I have a lens board nearly ready for the Graflex

[wombat2go]

Progress On the Speed Graphic-Pentax 6X7 conversion

Following my inability to wind the 120 film onto the spiral reel, I took a close look this afternoon.

Firstly, the plastic reel is an adjustable width type, however in the 120 film position, the sides of the reel are not accurately parallel because the centre concentic axles have insufficient length of engagement to hold themselves parallel. The concentic axles diameters are not sufficiently accurate dimensionally, too much free play.

Secondly, when locked into the 120 film width slots, the tolerances on the slots are too loose, so when I grip the reel to push the film in, the groove width is less than the film width, so the film bows, and binds where my hand pressure is.

Third problem makes the above 2 worse. I read on 3 forums that it is best to cut 45 degree chamfers on the leading edge of the film.

I am sure this is appropriate for an accurate plastic reel, however testing my plastic reels, when pushing the film in to the roller-coasters, the chamfer lets the film take the easy path which is to jump out of the groove. (Even in the light, this happens frequently)
So, using what I have here , I machined an inner axle which allows the reel sides to float (pushed apart by the film) and I no longer have to grip both sides of the reel.
Tests in the light were much better.

But now I have no bw 120 film left to try this mod, I hope to get some this week. Actually I need the lowest cost 120 film for these tests, and run my Ilford Microphen past its limits.

So I spent the remainder of the afternoon checking the rear shutter speed.
Here the Pentax 6X7 lens is racked out into a macro position, to focus accurately on the lamp reflector though a #4 oxy welding lens .
To collimate the photo-diode (shown moved away from the ground glass in this photo) I machined a puck of black acetyl, 10 mm long and with a 1.2 mm drill with a counter-drill 5.2 mm for the photo-diode. The puck is pressed to the ground glass for the test shots.
with the lens on f/4.5 this all gives a pulse of 4 microAmp above dark current through 5200 Ohm and on to my vintage but quite accurate Eico oscilloscope, ..probably of similar vintage to The Speed...
It measures the shutter exposure time sharply except I think the collimation is getting a bit ragged on the 1/1000th slot of the Graflex.

Attached Images

View Picture EXIF

File Date

 

[wombat2go]

Progress with the P67 on the Speed Graphic this weekend.

I had to make a new darkslide out of thin stainless sheet because the old plastic one was cracked.
Telescope flocking from Protostar was used to cover the rear of the lens board and the shiny P67 bayonet mount.
Loading the tank reel has been solved and a roll of Kodak 120 TMY 400 was exposed using the M4/3 as a spot meter and in Ilphord Microphen.
The Epson V600 is used to scan the 6 by 9.
1200 DPI can not resolve the overhead electric lines in the shot below.
Trying 1800 DPI which makes a 22 MB raw Tif on BW and will be about 66MB in 24 bit color.

The Takumar 67 1:4.5 75mm lens is losing sharpness right out on the corners of the 6 by 9, otherwise the images are sharp (limited by the V600)
I left the below photos untrimmed to show the full 6 by 9 corners, but they will be cropped to 6 by 7 or so in the enlarger.
The second shot is a tough one, the sun in the top corner and exposing the shaded side of the house.
I think it is a good lens - being 40+ !!
(These are downsized to 4MB jpgs)
https://www.box.com/s/98dvx2lwnbq07kjynkq1
https://www.box.com/s/dp69w7tibt5r73ik7c02

It is daunting to take a shot.
Here is the cheat sheet till I get used to it!

[stevebrot]

Progress with the P67 on the Speed Graphic this weekend.

I had to make a new darkslide out of thin stainless sheet because the old plastic one was cracked.
Telescope flocking from Protostar was used to cover the rear of the lens board and the shiny P67 bayonet mount.
Loading the tank reel has been solved and a roll of Kodak 120 TMY 400 was exposed using the M4/3 as a spot meter and in Ilphord Microphen.
The Epson V600 is used to scan the 6 by 9.
1200 DPI can not resolve the overhead electric lines in the shot below.
Trying 1800 DPI which makes a 22 MB raw Tif on BW and will be about 66MB in 24 bit color.

The Takumar 67 1:4.5 75mm lens is losing sharpness right out on the corners of the 6 by 9, otherwise the images are sharp (limited by the V600)
I left the below photos untrimmed to show the full 6 by 9 corners, but they will be cropped to 6 by 7 or so in the enlarger.
The second shot is a tough one, the sun in the top corner and exposing the shaded side of the house.
I think it is a good lens - being 40+ !!
(These are downsized to 4MB jpgs)
https://www.box.com/s/98dvx2lwnbq07kjynkq1
https://www.box.com/s/dp69w7tibt5r73ik7c02

It is daunting to take a shot.
Here is the cheat sheet till I get used to it!

Ha! Ha!

I used to carry an almost identical cheat sheet when I was learning how to use my view camera. Welcome to the world of primative photography!


Steve

[Swift1]

I need something like that for all my manual cameras.
Last week, I spent something like 15 minutes setting up for a long (1s) exposure with my Bronica, took the shot, packed up, and then I remembered I hadn't even focused the camera.

[wombat2go]

Progress on the P67 Speed Graphic conversion:
Waiting for a C41 kit to process the Fuji 400 120 Rolls so I post progress.
The camera has been out in the cold a few times and even to Canada, and is doing sharp shots so far.
I got carried away at Port Huron and fired all 8 6x9 shots before I realized I forgot another to bring another 120 roll
So I got out the Pentax MX and its metering failed (again, I have to pull it apart to fix) ) . We used the Oly M43 for the remainder of the trip.

I have been trying to use the only tripod which I ever owned, and old 1970's Velbon.
Totally inadequate structurally for the weight of the Speed Graphic with the heavy P67 lens.
Interestingly the shots with the focal plane shutter were sharp, but the tripod was in danger of a collapse.
So I found a used heavy duty tripod on Adorama for about $115. -See photo below.
Much better.

The lens board I machined was allowing shiny parts of itself and also the shiny lens mount to reflect a little bit back onto the film.
I don't know how the original P67 body handles this because i don't have one.
I covered the back of the lens board with self adhesive telescope flock from ProtoStar in such a way as to form a pocket so the P67 lens can be removed normally, while it covers the bayonet mount.
Taking this shot tonight with a flash, I was surprised to see additional strong reflection (see right side) from a black painted rail on the Graflex bellows. Not obvious in normal light. I will add another flap of ProtoStar flock.

[wombat2go]

I need something like that for all my manual cameras.
Last week, I spent something like 15 minutes setting up for a long (1s) exposure with my Bronica, took the shot, packed up, and then I remembered I hadn't even focused the camera.

My problem too , not to mention that I am by now too blind to focus anyway !!
18 mm on M43
75 mm on 6 x 9

these lenses while quite different in the images they produce , both have extraordinary depth of field
The 75 mm at f/8 at CoC 0.05 mm goes from a few metres to infinity., so at the normal f/16 or so, just use the scale.

[revdocjim]

What a great project. It catches my interest because I also have an old beater of a Speed Graphic with only one working lens, but a whole bunch of Pentax Takumar 6x7 lenses. Unfortunately I'm pretty sure my Speed Graphic doesn't have the focal plane shutter option.

As for loading film onto reels in the dark, I initially had only stainless steel reels and I found that with a little practice 120 has become extremely easy. But try as I might, I could never get good at loading 135 onto the stainless reels. So finally I bought a plastic patterson style reel and tank for use with 135 film.

[wombat2go]

Hi, revdocjim,
I think a Speed Graphic by definition has a focal plane shutter (The fast focal plane shutter was for sports etc)
Look for the big winder key in the side
It may have been removed in yours however replacement shutters are still available in USA.
Any way if you have a P67 90 LS it would be a good lens on the 6 by 9 rollfilm back if the focal plane shutter is not working.

[wombat2go]

Lens # 2 arrived and I finished its lens board today. Ready for testing
The lens boards are much stronger ( laminated Al plate) than the original Speed Graphic lens boards partly to take the weight, and partly to get enough thickness to machine the bayonet mount.
And the light trap is different.
The lens board is covered with telescope flocking to shield the shiny parts of the bayonet and forms a pocket to allow removal of the lens
I decided to make one board per lens because the front of the camera is not intended to take twisting when a lens is changed.

I still don't know what to do about the missing lens cap for the 55mm.
One thought since the front rack of the Speed is not used, as the front is back on the body rack to get the P67's 85 mm register, is to replace the front door.
Make a jumbo front out of Aluminum plate for the Speed which contains the biggest P67 lens I am likely to get, and cover it with matching leather.

I see that the Graflex cameras had many variants and modifications in their day, this would be just another one.

Ps Note the spelling mistake on the name of the Super Takumar The engraving is wrong, it is not missing paint. Was that original?