Great, I thought I missed something. Thanks for the clarification...Originally Posted by BarryS
65mm
90mm
Great, I thought I missed something. Thanks for the clarification...
I was given one of these last year and CLA'd it myself, so I learned quite a lot about its workings. As was mentioned by Corran, the highest speed setting is harder because when you turn the ring to that position, an additional, heavier spring is engaged that is not at all engaged at the lower speeds. That spring is there to give the extra force needed to cycle the shutter at that higher speed. For all the slower speeds, a weaker spring is engaged and then a geared mechanism with a catchment and pendulum thing is engaged by varying amounts to slow the shutter cycle for all speeds slower than 1/200. That retarder mechanism is what you hear buzzing with slower speeds. At 1/200, this retarder mechanism is simply not engaged. But for the 1/400 setting, extra spring power is needed. The designers probably didn't want to use a spring with that much resistance for all speeds as it probably causes more wear and stress and would require a more substantial mechanism to slow the cycling for lower speeds.
One thing I learned while studying the mechanism in this shutter is that settings in between the marked settings will most definitely not work as you might expect. You can't get reliable speeds in between the marked speeds to fudge the exposure a bit. The way speeds are determined is not a smooth slope. Each setting is sort of special and is determined by several factors. So you should only use the marked settings.
Interesting information about the Angulon lens! Are you offering to CLA Angulons? ;-) So, with all this effort to bring the extra spring into play, is there only a gain of a 1/50th as someone else speculated? Did you test the lens with a shutter speed tester? I see someone wrote an audio shutter speed tester for the iPhone: http://www.youtube.com/watch?v=tOcGn07YUpc Seems easy enough to do with any sound recording program.
As with many older shutters the highest speed often involves an "accelerator" spring which only comes into play on the highest speed. This was common on most medium format shutters on old folders. Since the highest speed is used less. the Accelerator springs often become harder to arm.
I have committed to buying one.. and today my 90mm f 6.8 arrived from Melbourne... Can't wait to get one in my hands... December seems like a while away... Great work guys... Cheers...
Len Metcalf
Leonard Murray Metcalf BA Dip Ed MEd
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This sounds like a great project, and so well designed too. I've built a couple of cameras and always had troubles with the backs. The Travelwide spring looks great. Maybe there's a market there for the pinhole and other builders to justify ordering a few extra springs to sell them separately.
To make it really cheap and popular I wonder if a Polaroid pack camera lens and shutter assembly could be hacked onto the front? They used to be incredibly plentiful, the 114 mm f/9.2 three element plastic Polaroid lenses already have a distance scale, so it might be possible to mount it straight onto the 65 mm Travelwide, perhaps with a bit of a shim. The lenses don't really vignette much on 4 x 5 but probably aren't real sharp in the corners.
You have to add a 3 volt power supply to operate the shutter/CdS sensor, but then you have automatic exposure, limited to around about 100 ISO film, with a bit of a tweak with the lighten-darken control. Flash is a problem though, unless you still have a supply of flash cubes!
I posted a message on APUG about adapting a Polaroid Colorpack 80 (1971-1976) to 4 x 5, but nobody replied so perhaps everybody thought it was a really dumb idea. My post, titled "Polaroid 4 x 5 point-and-shoot conversion with automatic exposure control" is at
http://www.apug.org/forums/forum147/...ml#post1162398
I think the lens and shutter assemblies on the new 6 x 12 Belair probably operate in much the way. They offer a 90 mm lens, but as I understand it the batteries (2x 1.5V LR44 button cells) and the shutter release are in the body so using this particular lens on a Travelwide might not be quite so straightforward, perhaps requiring a small extra lens panel with their bayonet fitting, along with the batteries, timer circuitry or an automatic exposure sensor, and a shutter release. That's assuming the register distances are similiar so the Belair lenses can focus.
However for down the track, this might be an easy way to make the Travelwide cheap and popular, if the supply of Angulons dries up!
Philip Jackson
I have a Belair (Yet to use it...) and indeed everything shutter-related is on the front panel of the body that pops out. Batteries, shutter, meter, everything. It could probably be popped off and put on a Travelwide.
What Dave said!
I question the value of putting automatic exposure on the camera. What is the target audience for this camera? Is it large format shooters who are used to setting aperture and shutter speed or is it point and shoot people who don't understand those concepts or don't want to deal with them? To me, it looks like a big hack to put that lens pack out front.
An advantage of requiring people to set their own aperture and shutter speed is that they will soon get the hang of it and not be so scared of the process. They will certainly be motivated after wasting a few sheets of 4x5 film, at $2-$4 a shot, LOL. Today's films have amazing latitude. This review of Portra 400 from Shutterbug says that you can basically guess at exposure, perfect for meter-less cameras:
• Bright sun: 1⁄250 sec at f/16
• “Cloudy bright” (overcast, but with clear shadows): 1⁄250 sec at f/5.6
• “Cloudy dull” (no clear shadows): 1⁄125 sec at f/4
• Indoors, room light: 1⁄30 sec at f/2
The designers could adapt these guidelines for the Angulon and publish them with the camera. Indoors is a problem, but the camera isn't called the TravelWide for nothing! Go outside! Of course, you can always stick a Gossen DigiSix meter in one of the cold shoes.
People are already complaining that the Angulon f/6.8 does not stand up to the Super Angulon f/8. How is the plastic Polaroid lens going to compete? LOL.
I think the fact that the designers said the camera was designed around the Angulon f/6.8 has been giving people the impression that it is the only lens that will work. The truth is that a large number of 90mm lenses will work on the camera. I think a list should be put up on the KickStarter website to help people in sourcing a lens for this camera.
It's true with the Graphex shutter in which the Optar is mounted, too. Of course, that shutter is really a Wollensak Rapax. It's a very nice shutter, but like most, the top speed is more for advertising than use.
The home-built sound-recording shutter testers that use light sensors wired into the sound-card microphone input may not be accurate with the higher speeds. We've discussed this a lot. It has to do with the way those inputs are filtered, and the way we should interpret the shape. And also that the opening and closing speed of the leaves becomes critical at higher speed settings.
Rick "who never uses the highest speeds on those small shutters" Denney
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