Would you buy a 100mm LCD shutter for $400?

[Vaughn]

No, this is something I would not be interested in. I usually do not use less than 1 second, and often have the darkslide pulled and then wait for the right time to make the exposure. Shutter needs to block 100%.

And the less things without batteries, the better for me.

[polyglot]

For those still interested, I can't get a straight answer from the manufacturers wrt contrast, so I'll probably just buy a small sample myself and do some testing.

[JR Steel]

Another variable. How would it be affected by temperature in the field?

[Leigh]

LCD response slows at low temperatures.

They are liquid, after all.

- Leigh

[Old-N-Feeble]

I'll bet the OP could add a temperature probe to compensate within +/-10 percent accuracy. However, I too worry about image quality through the device.

[polyglot]

Performance should be pretty consistent from -20C (well, certainly 0C) to +85C. You want to operate outside that range, too bad.

Clearly I'll need to demonstrate photos taken through a smaller prototype before offering these things for sale. Assume that if quality is insufficient then they won't be made available unless you swear to use it only for petzvals or worse

[genotypewriter]

Performance should be pretty consistent from -20C (well, certainly 0C) to +85C. You want to operate outside that range, too bad.

Clearly I'll need to demonstrate photos taken through a smaller prototype before offering these things for sale. Assume that if quality is insufficient then they won't be made available unless you swear to use it only for petzvals or worse

Looking forward to it. Don't let the naysayers get to you. Progress doesn't come out of thin air. Hope you come up with a good solution that works for some conditions even if it doesn't for all conditions. Not even LF itself is good for all conditions any way

GTW

[Struan Gray]

Polyglot: I say go for it. Experiment trumps armchair theory every time.

There are, however, some things to look out for.

1. You may need an auxiliary shutter if the darkslide is going to be pulled for a long time. The pi cells I have stumbled across (in other applications) have extinction ratios of a 200:1 to 300:1. That means you can safely pull the darkslide or remove the lens cap for 10-20 times the exposure duration with no issues whatsoever (assuming you don't have things like car headlights around). Practical, but it would require discipline/understanding on the part of the user.

2. In front of the lens the LCD may introduce flare. Behind it it may introduce flare and a bit of spherical aberration. I honestly doubt either are going to be a big deal with the sort of vintage portrait lenses which currently use a Packard or a hat.

3. Polarisation may bite you. First the 'on' transmission will be one or two stops down from a simple hole, and that may tip the balance for those really fighting for enough light like ULF or wetplate users. Also, there may be interactions with polarisation in the scene in front of the camera, leading to uneven skies or visible stress patterns in glass and plastics. Finally, anyone wanting to use a polariser for the usual photographic reasons would either have to be able to rotate the shutter, or would have to use a circular polariser out front instead of a linear one.


I don't think any of these are deal breakers. I would love to have an updated Sinar shutter using this technology, the bigger the better. If you are thinking of fully commercialising the idea (as opposed to a shareware-like make-a-profit-but-not-a-living business model) I suspect your biggest problem will be competing with all the eBay copycats who jump on the bandwagon once you have done the hard work of proving the idea works.


PS: 100 mm is a little small for my 'problem' lenses. 130-140 mm (fit inside a typical 4x5 format frame) would be *much* more interesting.

[E. von Hoegh]

Not if the movement of one part is countered by the movement of a similar opposite part. e.g. six shutter blades evenly spaced will cancel out each others movement.


Steve.

You are utterly wrong, I posted an explanation why should you care to read it.

[Jay DeFehr]

Polyglot: I say go for it. Experiment trumps armchair theory every time.

There are, however, some things to look out for.

1. You may need an auxiliary shutter if the darkslide is going to be pulled for a long time. The pi cells I have stumbled across (in other applications) have extinction ratios of a 200:1 to 300:1. That means you can safely pull the darkslide or remove the lens cap for 10-20 times the exposure duration with no issues whatsoever (assuming you don't have things like car headlights around). Practical, but it would require discipline/understanding on the part of the user.

What if you stacked two LCD shutters?

Could an LCD shutter be made large enough to use at the focal plane?

One application I see is for using lenses like my Verito, which are aperture-dependent in their effects, so if I want to shoot in bright natural light at wide apertures, I need either a fast shutter or a slow film (or a ND filter).