film flashing question

[Wade]

This shot between 1:40 and 1:55 was flashed, as an experiment. Since the whole shot is dark its not really easy to tell if flashing had any effect. In fact, I suppose the lighting in the subway is actually less contrasty than straight daylight--not a good shot to experiment on. So, has anybody ever used flashing before, and how is it done?

https://vimeo.com/139887229

[slashmaster]

This shot between 1:40 and 1:55 was flashed, as an experiment. Since the whole shot is dark its not really easy to tell if flashing had any effect. In fact, I suppose the lighting in the subway is actually less contrasty than straight daylight--not a good shot to experiment on. So, has anybody ever used flashing before, and how is it done?

https://vimeo.com/139887229

Never done it, what is it? Looks like you've got usable stuff though. I've got tri-x 200 asa footage of Boston subways which mostly worked good, but still a little too dark at the maximum f-stop.

[Wade]

Never done it, what is it? Looks like you've got usable stuff though. I've got tri-x 200 asa footage of Boston subways which mostly worked good, but still a little too dark at the maximum f-stop.

I've never done it either, nor do I know anyone who has. Flashing, I believe, is "one-lighting" an exposed roll of film in order to bring detail out in shadow areas. For example, if a documentary is being filmed and lighting equipment, or even a reflector couldn't be used, and the lighting is really contrasty, and they were using a narrow latitude film stock, like a reversal stock, one option was that the contrast can be made less harsh by flashing the film after it is exposed. It brings detail out of the dark areas, while leaving the lighter areas not over exposed. I suppose if one knew what they were doing they could deliberately expose knowing they will flash the film and possibly get acceptable results. I might be able to find a lab guy who knows about it.

[David M. Leugers]

I used a 10 percent flashing to lower contrast by boosting the exposure in the darker areas of the image without blowing out the highlights. The effect on Kodachrome was subtle, but produced the desired effect of better balanced images taken in scenes with bright sunlight mixed with heavy shade. The different look given to the footage was what was gained rather than a perceived increase in film speed if that makes sense. You expose the film at your normal film speed, the flashing just affects the less exposed areas. More flashing (say 20 percent or more) is not generally used but one could experiment. The flashing can be done before filming or after filming. I preferred to flash before because I wanted to be sure the footage I shot was not ruined by some accidental over exposure during the flashing part. Just one thing less to go wrong the way I saw it. I filmed a Kodak gray card evenly lit with the lens out of focus with the card (longer lens focused on infinity ) with the card just filling the entire frame. A 10 percent flash exposure is roughly 3 stops under exposed. Determine the correct "F" stop to film the card per your setup if you were filming normally, then stop the lens down 3 stops to underexpose the card. The film has to be rewound if 16mm single perf before filming your footage, otherwise reload the roll film and shoot normally. I think the difficulty performing this with S-8mm cartridge film makes this really a roll film procedure. If you have a R-8mm or DS-8mm camera you could flash half the roll and then shoot the entire roll of the same scenes for a comparison. Projecting Kodachrome shot this way the images had a little less "punch" in the images, but the film transferred better to video. I suspect E100D would have similar attributes or any other contrasty reversal stock. I never tried it with B+W.

[doug]

I use a similar method as David's but post-flashing, so only parts of the roll need be done. I really like the way E100D behaves when flashed. Yes I'd say rather like Kodachrome which I also used to flash. With post-flashing I suppose there's a slight risk of ruining everything, but I only use unbroken sunshine so bar the odd eclipse no problem. I shoot a black card out of focus (and in the shade) and after metering off a grey card I generally overexpose by about half a stop. This gives a nice pastel effect if that's what you want, and I'd think should help the scanning later, by keeping the contrast within limits.
I also like doing rephotography off projected slides and film, and for lowering the contrast it's quite easy to introduce some flashing with a light bounced off the ceiling or wall.

[doug]

Looking at Wade's footage it's a little hard to know what the effect would have been without flash. I've never tried flashing monochrome. Maybe it's less effective than with colour. Although if the aim is to simply lighten up dark areas maybe it's worth it anyhow.

[Wade]

I filmed a Kodak gray card evenly lit with the lens out of focus with the card (longer lens focused on infinity ) with the card just filling the entire frame. A 10 percent flash exposure is roughly 3 stops under exposed. .

I used a grey card under exposing two stops, out of focus. Using a Bolex B8LA, which has a rewind slot, I shot the grey card, and rewound it and took the subway shot. I will experiment again with a more contrasty scene.

Looking at Wade's footage it's a little hard to know what the effect would have been without flash. I've never tried flashing monochrome. Maybe it's less effective than with colour. Although if the aim is to simply lighten up dark areas maybe it's worth it anyhow.

I might even experiment shooting a white card to see what happens. After all, it's B&W, so I probably don't need to use a grey card.


Thanks guys. It's good to know other people have done it successfully.