Hello fellow stop motion-ers!
I have managed to teach myself enough to make a few stop motions, but I still don't quite understand what type of lighting/bulbs to use to prevent the subtle flickering throughout an animation? I want to be able to achieve a clean, consistent look but I don't really have the money to spend on professional Dedo lights and the like.
Does anybody have any wisdom or advice on the subject? Any help at all would be hugely appreciated!
Below is a link to my latest attempt at stop motion. The flickering effect almost suits the tone of the film here, but I would love to know how to control it for future animations.
There isn't much flicker in that film, didn't bother me in this one. But usually it can be distracting.
Assuming you have your camera set up so it doesn't have any variation in the exposures (either from auto exposure or from the iris not stopping down in time when you press the shutter), the variation is likely to be caused by a slight change in the voltage of your mains AC power. That's what I found when I set up my own studio at home, the voltage would vary by one or two volts, over a minute or two. Most lights go dimmer or brighter when the voltage changes - that's how dimmer switches work. Taking individual frames with a minute or two between shots, that showed up as a noticeable change from one frame to another. I was thinking I would have to specialise in films set around a flickering campfire!
I went with an expensive solution - a Double Conversion UPS which converts the mains power to DC voltage, stores it in a battery, then converts it back to AC power. Voltage is 2 or 3 volts less, but it stays consistent. With that, I can use little Par Cans from a disco lighting supplier, or home-made lights I made with 50 watt halogen downlight kits, compact fluoros, stage and TV lighting, pretty well any light, and it stays steady. A plug-in unit costs around $1500 so they aren't cheap. Mine is higher capacity and hard wired in to my overhead lighting circuit which I had already had put in, and cost even more, about $5000 when you add in the electrician to install it. So not the way you want to go at all!
Without a steady power supply, some flourescent lights may maintain a constant brightness. If they are not dimmable, they don't respond to small changes in voltage, they stay the same until the voltage drops too much, then cut out altogether. My 4 ft long, ordinary fluoro tubes in the ceiling, used for workshop lights and sometimes to add soft fill light, don't seem to change brightness. They aren't on my filtered power circuit, but they don't vary. But they are such a large source of light, they always look very soft, no hard shadows and not much control over where the light goes. They are only good for certain things like just brightening up the ambient light in the room a bit so the shadows aren't so dark, they are no good as key lights. I thought maybe if they worked, then all fluoro lights might work, even the little compact fluoro bulbs for rplacing your incandescent lighting. But I am not sure about that.
I got a kit for lighting products in a soft box, which has 3 lights which are those coiled flouorescent light bulbs. they screw into a round reflector, so they can be aimed. I thought they might work without flicker too. But I hooked one up to a dimmer switch to see what it did. It doesn't dim properly, but when you drop the power just a little bit, it does get slightly dimmer, then when you turn the power down a bit more it starts flashing, and a little further down and it goes out completely. That very slight drop is what happens if the AC power is uneven, so they would go slightly dimmer. I would try some other compact fluoros just to see if there are some that can be relied on. They can be screwed into any ordinary fitting. I used a cheap dimmer switch from Ikea to test my fluoro lights.
Thanks so much for your detailed reply! This is all really really useful. I'll definitely find some compact fluorescent lights and a dimmer switch to test, and let you know how my experiments go.
Do you know anything about LED light bulbs?
LEDs, good point.
I have some LED ceiling lights installed in the living room that replaced the halogen lights that used to be there, and they had dimmer switches. But the electrician said these LED downlights wouldn't work with our dimmers so he didn't run them through the dimmer switch. So worth looking into. Because they are hard wired in, I can't test them, but LED lights are coming down in price now. There are LED replacements for the PAR cans I use for sale, don't know if they are dimmable or not. I do have one compact fluoro globe that is sold as dimmable, but it requires a different type of dimmer, so doesn't work with any of mine. So not easy to figure this out.
A couple of pages with info on LED par cans:
Many of the LED lights I'm seeing on eBay come with 3 colours, so you can run them through a controller and change the light colour, great for a party but not helpful for film lighting. It's also hard to judge the size of the light, the little 50 watt par 16 halogens I use look a lot like a much bigger one Par 64 model in a photo.
Looks like sone LEDs are dimmable:
Which means they would change brightness with small changes in voltage, I guess. Actually it says both LED and Halogen in the heading, probably to pick up more hits, so you can't trust it to be accurate.
Ok, don't know about you but I'm more confused now than I was before!
One thing about LED lights - the ones I've seen anyway actually use a bank of those little LEDs rather than a single source. I've had LED bicycle headlights and flashlights and they're like that, a dozen or so tiny bulbs grouped together, so rather than a single-point source you get this weird multiple illumination resulting in lots of shadows overlapping each other - looks really weird and I don't care for it at all. But there may be some units that are configured differently or something, I don't know. Also the ones I'm familiar with all have a harsh blue-while light that I also don't care for. So altogether I get an impression of something electronic and artificial trying to be forced to act like the more familiar light sources from analog days and not doing a very good job of it.
I have an LED torch (flashlight), it has a cluster of little LEDs like you say, and blue-white light. But I'm not not really seeing multiple shadows, more like soft edged shadows because all the different angles of light make them overlap and blend together. They could be a good substitute for a halogen with a diffuser on it, where you want to soften the shadows a little. The DoP that lit 2 films I worked on used light bouncing off white cards for nearly everything, so a bit of softness would been fine with him. But if you want a hard edged sharp light like the sun on a cloudless day, or a film noir look with very well defined light and dark, neither LEDs or Fluoros do that as well as a halogen light with a single small bright light source.
Hmmm - does that flashlight have a reflector behind the LEDs? That might be what's softening the light. I got this weird thing called an Ott-Light that looks like a flip phone - you flip it open and the light comes on automatically. It definitely gives hard-edged multiple shadows, but I believe the backing behind the LEDs is black plastic, not reflective. Not sure, I'd need to check on that.
Yeah, I think LEDs could definitely be good for some soft diffused lighting. Not so much for keylights, as you already said I think.
EDIT - Ok, found it and popped it open. It was really hard to see what's behind the LEDs because - well, when it's open they're on, so I was looking into intense white glare! But it turns out there's no backing at all - the LEDs are inset into little recesses in a flat black plastic surface. So each casts its own extremely hard light - I held my hand in front of it and got a shadow with about 57 overlapping fingers!!! Would probably work as a soft source with enough diffusion in front of it though.
Perhaps is you? (min. 0.35 - 1.00)
If you stand on X spot while releasing the shutter make sure to park your self there every time. Your body reflects and absorbs light even if you are not aware of it. The camera is particularly prone to pick this up when working with slow shutter speeds.
Oh yeah, the LEDs are spaced almost an inch apart in my little Ott light! I guess it's a way to get more coverage with less LEDs, sacrificing softness for utility. It's good to know they aren't all like that. I might try gelling it to turn the light more warm. It seems like it's not emitting much in the yellow/orange wavelengths to begin with so filtering out all the cool color might dim it significantly, but it's worth a shot! Especially considering it's really bright to begin with.
I've used Philips Hue LED lights with my current stop motion project. The lights have some kind of wifi built into them and require a base station hooked up to your wifi router. Something like 99 lights can be controlled by an iPhone app. Seems to have an infinite amount of color control as well. I haven't have any flickering problems with them as of yet. This test shot has 2 Hue lights, one incandescent for the fire place, and a string of LED lights for the Christmas tree.
Hopefully that link works.