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Optical Distortion In Shot

>I'm shooting a spot in a cabaret (canon XL1). its a dark room with only candles on the tables, intimate, seats about 120 people. the lighting grid for the stage is well stacked, so all the shots towards the performers i can light. but then i have to do a reverse and shoot the crowd clapping from the performers POV. I think a roving spotlight will add some effect for this reverse but the table candles need pumping up.

>I'm considering 'peanut' bulbs behind the candles which are of the small glass "bar room" variety about 3 inches high and two inches wide. id like to ask advice on the smallest battery to bulb set up i could rig. maybe maglite bulbs wired direct to a 9volt or AA batt? also thinking of double wicked candles but dont know where to find them.

>I'd also like to distort the optics for several shots. the opener is fingers on a piano. i'm planning to use a mirror near the keyboard to get a "piano POV" on a long lens with selective focus (narrow DOF). the script calls for "slightly surreal". i want to find a way to achieve some curvature of field- like fisheye distorion but on a long lens. edmunds scientific says any glass they have will throw evryhting out of focus. i thought of bending a sheet of lexan or plexi, or even stretching saran rap (sandwhich rap for the aristocrats who dont speak american).

>Any thoughts?

>I have a 1 gallon glass jug from the health food store. the curve looks great to me. anyone know where i could take it to get it scored and split? ( I need to ask Jeff K and Gladstone to be kind with the preceding sentences) thought id better ask before my girlfriend comes over and finds me out back in a pile of shards with "just the right piece" in my bloody claws.

>Lastly, anyone ever shot thru water on set? i have a hunch that shooting thru some water would work well with video in this club lighting. all i can think off is a small fish tank. jiggle it, stir it or just let it bend the light. food coloring?

>Thanks in advance all.

>Caleb "no dont white balance. i think...just a couple more drops...of yellow..." Crosby

>its for an agency that i'd like to impress

>Well Caleb, since you asked so nice, and by the way it is Mr. Gladstone. If you have an eternity, you just might try using a file to cut through the Glass. There was a Twilight Zone episode ( The original Series) where they wanted the point of view of someone having bandages removed. So the cameraman reportedly found a big fish bowl to put in front of the lens.

>Steven ( how did I get such a reputation) Gladstone

>You might try an old trick from science class. Saturate a piece of string or "butchers" twine with alcohol. Tie it tightly around the jug. Light it and let the glass get hot and then submerge it in a basin of cold water. It should fracture at the line of the heat. (Use an oven mitt to hold the jug just in case...)

>A more tedious, but accurate, way would be with a glass cutter - get one used for art glass with a ball on the end of the handle. Score around the circumference of the jar. If you can get your hand in through the top (I assume you can if it's a one-gallon food jug) tap from the inside along the scored line with the "ball" end of the glass cutter. You'll see the glass fracture and then separate. (If the jug has a small opening, like for cider, I've used a coat hanger to extend the glass cutter and stick it through the opening for tapping purposes...)

>Glass cutting is a practiced skill, having worked in stained glass years ago, clear bottle-glass is a "no-brainer" once you've got the touch! As long as you've got some kind of access to both sides if the glass, score the front, tap from the back. Should work fine. After you're done cutting, use a sharpening stone (also a hardware store item the grim reaper uses to sharpen his scythe) to grind smooth the sharp edges.

Paul K. Miller

Autologic Information International


>My two cents on use of glass for distortion: I did this once for a commercial with body-painted children which was supposed to have a strange underwater look. We had the art department buy about 10 vases and jugs, and just moved them around in fornt of the lens by hand. Some we put the lens inside the jug, others we just moved them left to right and top to bottom in front of it. Great effect! Worked really well and the footage was beautiful. Don't be worried about just one vase and cutting it perfectly. I say, if you have the time and resources, have a box ready and experiment...



>I once did a trick where we recorded a scene on video, and then played it back on a monitor. The monitor was laying on its back, looking up, and we positioned a very shallow glass aquarium filled with water over the screen. Then we pointed a film camera from above at the monitor, now filming the monitors screen through a thin layer of water.

>If the water was perfectly still, you could not tell that it was not just a monitor being filmed. But when we used a compressed air can to blow ripples in the water, it looked as if the image itself was rippling. This was before digital effects could perform such tricks, and it is a lot of fun experimenting with multiple air cans and/or food colors in the water. Certainly a surreal image, and something I still prefer over the cheap digital effects we are often assaulted with these days.


>Marc Shipman-Mueller, Technical Representative Arriflex Corporation

>Try some Plexi mirror. I used that on a Triathalon/Car spot last year and the effect sounds similar to what you're after.

>Another thought... How about shooting through some heat shimmer? Sterno cans (three together) work well but flame bars or a blowtorch work even better.

>David Perrault

>Or old ferrotype tins--the chrome-plated flat metal sheets we used to ferrotype glossy B&W prints on. They're very flexible and gave us beautiful results on a ghostly apparition we shot to super over a bonfire.

>Wade Ramsey

>Hi Caleb,

>I've had decent luck visiting stained glass shops and antique stores when looking for ripple glass and other interesting glass effects.



>hearty thank you to mr. David P, Steve G, Paul M and Koen S. for the great help with my recent optical distortion question.

>i found several subtle plates of art glass at a stained glass shop. one was called "water glass". had them cut special and moved them by hand across the lens during the takes. it was a cross between water ripple and heat shimmer. really a pretty application, thanks for the great ideas. the agency creative director bought me a martini after the shoot and is my new buddy ; ]

>used the bent plexi glass mirror idea - which gave great curvature of field- combined with the ripple it was just what i had in mind for the "hands on the keyboard shot" of the pianist. and with my trusty dedo, it was darn good looking v- d -o. (pardon)

>special thanks to Geoff. i could see what i wanted in my head but was foggy on how to apply the mechanics. CML is an right trusty anchor to windward. words are too easy but the next time i get full rate im sending a negotiable instrument of thanks- you know where (no not _there_!)

>also found the lid to a solid glass box in antique shop- about 1/2 inch thick that gave some great *bend* for some other shots. paid 15 bucks for it and thought i did ok - until the inevitable happened (yes it did fall but only cracked the corner off) (hard floor too, but thick, strong, manly DP glass)

>but no, the inevitable was picking up an ashtray in the bar between takes and realizing it gave the exact same effect - for nothing.

>Caleb "available filtration" Crosby

>"My wisdom is for my friends, my folly for myself. Goodnight." -Capt. Frederick Marryat