Idea pitch: Electrochromic glass shutter, would it be possible?

[Bob Salomon]

Its just another filter, Bob.

And most filters are pretty poor optically.

[rdenney]

And most filters are pretty poor optically.

On the other hand, a lot of the vintage barrel lenses to which such a technology might be applied are also pretty poor in terms of resolution, and people use them for their other qualities.

That said, Sinar shutters and Packard shutters do actually fulfill at least most of the requirements in making an old barrel lens usable, and neither require batteries.

Rick "developing a long-term hate relationship with batteries" Denney

[Jody_S]

This absolutely would work for large barrel lenses, but only behind a Packard shutter. Of course if you're going to go to the expense of buying a large Packard shutter and putting this together, you could just buy a 4x5" or 5x7" camera with a focal plane shutter and cut that up to use behind your barrel lens, and have no light loss and much less experimentation to get through. So this is only practical if you need speeds above 1/1000s, which is pretty rare these days with large format.

[Havoc]

I think it would be far more easier and faster to get an electronically controlled curtain shutter set up and working. Or one scale up one of those DSLR shutters. With film on a normal day and 4x5 i'm happy if I can use 1/30!

While filters may be "poor", I'm very sure that we cannot get the same parallelism between the lens plane and the film plane than the cheapest, clumsiest, garden shed made filter can achieve. If you would clamp the outer race of a chinese ball bearing between 2 commercial window float glass panes, it would be more parallel than a Linnhoff Technika coming out of the factory in 1970. Let alone after 30 years of (ab)use.

[Pere Casals]

I would like other options.

Smart glass will not be practical because it won't block all light and it may degradate image quality.

This is an smart solution: https://www.largeformatphotography.i...struction.html


Also it's time to recall the Galli shutter, I calibrated mine with a shutter tester, and with some practice it's way more accurate than one may think:

https://www.youtube.com/watch?v=ICLG3HCDlhk

[Drew Wiley]

Photochromic and electrochromic glass have been around a quite awhile. The latter is commonly used on highrise windows where the shading can be electronically controlled for sake of energy savings. It doesn't react that fast. I can't imagine using something like this for a shutter, but then, landing on the moon seemed impossible too. It just took a lot of time and money.

[Havoc]

What about a moving/rotating mirror? It would require rethinking of the camera and way of composing. Like the rotating mirrors used for scanning labels or the line scanning "helical" in the beginning of tv. Can't find it directly but it looked like slits of mirrors stacked like a helical that rotated.

Those moving mirror cameras were used for fast recording of events. The rotating mirror sweeped the image past a long strip of film.

Google is horrible these days.

[LabRat]

One of the other issues that would come up is falloff...

I had heard that when using Leica M lenses on digital cameras, UWA's would exhibit fall-off due to the severe cone of light that would deflect off the sensor glasses at the outer areas more, so UWA'S had even more fall-off... Current lenses for digital have a less severe cone of light nowadays...

I was looking to develop a personal silent camera back in the 90's (when I did theatrical photography) using a cell, but didn't get too far, as mentioned there was significant light loss and not 100% sealing when closed... The units were (then) big and realitively heavy to fit into a 35mm as I hoped, so the project got scrapped...

Glass can be used in the camera, as those plates in the moon Hassy's had them, and of course in front of digital sensors...

There's other ways to skin this cat, with much smaller shutters on the lens side of the camera...

Steve K

[Pere Casals]

Glass can be used in the camera, as those plates in the moon Hassy's had them, and of course in front of digital sensors...

But glass should be of certified flatness for optical usage and it should sport anti-reflective coating, of the MC kind if possible, if we want to conserve optical performance.

[Drew Bedo]

This problem was addressed in the early days of photograp;hy. Back then the solutions were things like the Packard-Ideal shutters and the Thornton roller blind shutters.

Interestingly, both types can be found today. Some working with traditional alternative processes prefer to use the most period correct gear. There are others though who will screw a 150 year old brass lens into a modern leaf shutter with a custom machined cross-over adapter.

Another option is to get one of the 4x5 press cameras with a focal planer curtain shutter.