Had a comment about this on my previous post so thought I’d put abit of info in on green screen. Everything herein is pretty much self taught as I’ve not really been able to find much info on chroma-key (as it’s also known) so I’m sure there’s plenty of omissions, but here goes…..

So first off you need a green screen. My first attempt involved painting some boards green with the brightest green paint that my nearest DIY store could mix. Despite being a cheapo option this actually worked!….well, kinda. Here’s a still from my first stop motion animation ‘Real 10‘.

OK, so doesn’t look too bad?  Well actually this will be (and was) a pain to get to work.  Obviously there’s a large section to the right which the green screen doesn’t cover.  This isn’t actually as much of a problem - I routinely place masks over chroma key shots (i.e. placing a green section of image over the area to cover the section).  These are usually .pngs as the images allow you to have transparent areas within the image, allowing the section you want to keep to show through.

The problem with the rest of the image is the shadows and uneven shades of green across the image.  The bottom is much darker than the top.  I ended up having to repair the greenscreen frame by frame in photoshop for this shot, which isn’t ideal - it’s rather time consuming.

The key to getting shots ot work is to make sure you have an even colour across the background so that the computer can easily eliminate it and replace it with the background shots you want.

A background with a flat background colour will make it easier for the computer to isolate the green screen sections.

The main way to achieve this is decent lighting. I used halogen security lights on my first animation.  These are good because they’re cheap, however they also do not produce even levels of light - as the element heats up the colour they emit changes and the levels fluctuate.  Because of this one frame of your animation will be brighter or a slightly different colour than the others.  You end up with a flickering effect when the frames are played back.

I’m now using photography lights which seem much better, though they are a little more expensive.  I’ve also got a fabric greenscreen and stand which can be had from ebay for about £100.

The last thing you need is some software.  I’m currently using Pinnacle Studio which is abit of a cheapo program, but it does combine the chroma key tool with an editing interface.  Adobe After Effects will also do the job.  I’m sure there’re others.

Here’s a short video showing some of the green screen elements for my animation Real 10:

So been a while since I posted anything, not because I haven’t been doing anything (well it’s partially that I’ve been lazy!) but also because the shots I’m currently working on are some of the more complicated involving meshing stop motion animation shots of the robot with live action.

As it turned out the shots I filmed without the green screen were much better than those with.  I think this was mostly down to the lighting levels which were altered when the green screen was put up and blocked out alot of the natural light which was coming in through the windows.

Unfortunately I didn’t have enough lights to match the levels I’d need to replicate the correct levels, which just goes to show the budget I’m working on (I think I spent about £250 on lights, not exactly a massive amount!).

Because of this it’s been more difficult to integrate the live action footage with the animation shots, in most cases requiring me to remove the windows in the shots where the robot can be seen outside frame by frame and then inserting footage of the robot behind where the windows were.

The shot where Tom and Pete see the robot and panic is 64 frames long, and each frame was done by hand one after the other in Photoshop.  The shot where the robot punches through the wall was about 30 frames, but was slightly more complicated as I had to animate the wall breaking and then composite falling debris over the shot as well.

So, currently working on the Measure of a Man Music Vid. I’ve done four or five shots so far and it’s going OK.  The chroma key shots are coming out fairly well.  I did have abit of a problem with the ammo clip on the gatling gun which I’d absent-mindedly painted green.  Because of this it was turning transparent once the chroma key filter had been applied.  I ended up painting it black, but you can still see through it in a few shots!

Other than that had a minor disaster when the robot puppet took a nose dive off the table halfway through animating a shot!  It broke into a few pieces but was luckily easy enough to fix.  Gave me a heart attack though!

Some shots are unfortunately requiring me to go through them frame by frame in order to incorporate some of the robot shots.  As you may imagine this is rather time consuming (the current shot has 64 frames for example).  Hopefully it’ll be worth it!

Here’s a short trailer I’ve done for the video which incorporates some of the shots I’ve done so far.

I’ve decided that the interior shots will all be black and white while the exterior shots will be in colour.  This is partly to try and differentiate between the band and robot shots, and also to make the video look slightly more stylistic.  It also means I can have some cool shots where the band are in black and white and the robot is in colour.

So this animation has kinda been put on hold so I can work on the Measure of a Man Vid, however it is still being worked on, albeit abit at a time. I had a problem whereby the set was pretty much taking up my entire front room.  This meant I hardly had any space to work in and as the set was raised only about 10cm above the floor I couldn’t get any low shots as the lowest my tripod could go was about 40-50cm.  This meant I could only ever get shots of the puppets from above which was somewhat limiting.

I’d also encountered a problem with depth of field; basically my plan was to photograph the puppets in front of the set so I didn’t have to worry about green screen, however the models appeared as though they were only a few feet in front of the set.  This is because they were ; the puppet and set were both built 1/6th scale, so if they were full size they’d be a couple of hundred meters apart, however the camera isn’t fooled in the same way as the human eye and the effect was that they appeared as though they were very close together. You can see this in this short trailer I produced:

In miniature photography, smoke is often added to help with depth of field, this wouldn’t work in my case however as the smoke would not look convincing when photographed for stop motion animation - it would move and disperse and so the end result would appear to flicker as the smoke moved between photographs.

In order to get around this problem I decided to photograph the set separately and then use green screen to composite in the puppets at a later date, the same method I used for my previous animation Real 10.

This means I can dismantle the sets and actually get my flat back!  Here’s some of the pics I’ve took.  I’ve used photoshop to extend the sets beyond where they oiginally ended and also to add artificial blurring to elements that are further away.  This lets me fake the depth of field effect.  I can also then blur the background elements seperately whilst keeping the puppets in focus.

Been screwing around with some promo shots of my brothers band and have inserted the robot behind them, presumably about to kill them with machine guns.

Mostly just a practice to try compositing the model into a photo.  I’m beginning to wish I’d put less wires on it…..!

Finished the robot (more or less) just a little bit of painting left to do.

Another update on the robot.  It’s now got a head and right arm.

The arm’s a large gatling gun.  I’m painting it military looking green to suggest it’s a new addition - the idea is that the robot was originally some kind of industrial piece of machinery which has become self aware (that always happens with robots) and nicked a gun from some military robot.

Need to add details to the neck which is looking kinda bare still.

The feet contain fuel tanks and a fenced off power generator.  I figured if you had a piece of machinery like that you’d want key sections near the floor so you can easily service and refuel it.

The left leg has ladders and platforms so the former pilots could easily get up  to wherever the cockpit is.

Here’s a few more up to date pics. I’ve been doing a fair bit of painting.

Sounds odd that I should want my robot to look like a skip, but I found some great reference for the kind of look I’m going for.  There’s some really cool weathering on this skip which is in a local park near me.

I’m now busying myself painting the robot to a similar effect.

Been working on the robot, here’s some pics.

Here’s some pics of the details on the back.  It’s all made from found objects; the big pistons are mini bike pumps, there’s bits of action figure in there and pieces of my old camera which I accidentally smashed.  The pistons all work and will move as the robot walks.

Turning my attention to the head now.  Not 100% on it yet, so might change what I’ve done….