Slit Camera, Zenit, Low Tek

whats a slit camera do?
imagine a thin slice from the middle of a photo then keep taking that photo again and again putting the strips side by side you end up with horizontal stripes
,then something gets in the way of the photo the stripe configuration changes,
the film is constantly moving,if something goes past the slit at the same speed as the film is moving it appears as normal in the photo but with a stripey background.
another interesting effect is the way that  objects traveling in either direction will always go the same direction as the films movement.
thirdly if say a car puts its nose across the slit then reverses back without fully crossing,the result is a car with two noses.

so there are several slit camera designs about,http://www.flickr.com/photos/limerick37/6931440568/ as im not really into programming, my design will not be using any, iv also tried to keep the maths to a minimum, i did some maths to work out what effective shutter speeds iv got, this test image was done before i did the math.

stuff list.
most of this i already had

bluetooth device(4printer) pogo printer or label making stuff,
battery drill,step bit.
vice
marker
rule
tiny files
hot glue gun,
epoxy fast rapid and strong............ £5
scalpels
thin scrap metal
heat-shrink
enamel paint
small pliers
wire cutters
wire strippers
strip-board
solder
paintbrush
wire
calculator
tin snips
motor regulator............. £15?
led running light............. £7
gears assorted
goggles
camera film..........£1
thinners
axle grease
spray glue...............£5
mini drills
p180paper
small blowtorch,
eyelets and setter................,£5
motor-gearbox,................... £20
butane.
spatula
mosquito forceps
solder iron
solder pump
pliers
round nose pliers(open camera)
body filler
batterys and holder.............,£5
leatherette
stopwatch
scissors
screwdrivers
files various
watch screwdrivers
hand reamer
broken camera ...................£2.2
polishing paste and pad
cutoff disks
dremel style tool
small metal boxes (torch and tobacco tins)............£3

after some experimenting with electric kits from maplin to get a system to make the thing work,these are the things i didnt use, i considered counting the pulses from a stepper motor driver to get a numeric output. or using a strobe to tell a stepper to step. the pic chip on the up down counter was dead out of the box, and the stepper was not a smooth motion also it needed recalibrating every time the battery was removed.

to avoid the maths involving, the speed and distance of the thing being photographed , and factoring in the length of the lens, i opted to have a visual representation of movement across the viewfinder, a led running light, which i could somehow make the film move at the same rate, i thought i could use a twin pot so one knob could control the speed of the motor and the speed of the lights. one of the leds on the running lights died so i replaced them all with smaller colour changing ones.http://www.youtube.com/watch?v=1ajbtlqK49o&feature=plcp

for the film drive i chose this motor , bit expensive but still very good, also a variable speed regulator made by the same people. the only ratio maplin supply s 148;1 , others are available direct from the manufacturer ,who are nice and helpful they deliver stuff as well. i did have an issue which was the resistor controlling motor speed was 10000 ohms and the resistor controlling led speed was 1000000 ohms , so the twin pot idea went out the windowhttp://www.mfacomodrills.com/gearboxes/gearboxes.html

so having most of the electric bits ready ,its time to get a donor camera, current non  go cameras i have are. i was going to use the zenit e because its got an uncoupled light meter , the light meter is completely separate from all the mechanical components, the zenit b was completely jammed so out of curiosity i looked inside to see why, iv unjammed these before with shock and force before, its one of my all time favorite cameras because of its minimalism . the shutter curtain came unstuck and was wrapped around some gears

so removal of the shutter commenced ,i reassembled it as best as can be done out of the body, the prism and mirror have to get out the way also. tigers lair website can inform on deconstruction.he is not keen on links.

i wanted to keep a viewfinder, i considered a mirror lock up knob on the bottom, thats where the cam that does that is located, but after tapping a thread into the brass gear it soon striped .instead i went for a split mirror also it means i can shoot and view at the same time, the drawback is that focusing accuracy might be a bit off, remove the mirror and use a glass scribe then snap. some scrap metal shields the slot from straylight, painted mat black to keep the light clean, my matt black has a distinctly gloss finish? mixed lids probably , i later used some rubber over the paint to get a matt finish , i would have liked to use velvet but i havent any.

 a box for the electrics is required , a poundland torch .wish i had bought a couple. stripped and glued to the back with some ridiculously strong glue, this stuff requires heat to make stronger, i used intermittent blowtorch to heat up has the bonus of speeding up the drying time      http://www.youtube.com/watch?v=Sz_2BL3ei6o  used a dremmel with fiberdisk ,step drill , square file ,and hand reamer to make holes in box

after finding some useable cogs for the drive, old vcr . i can glue motor on i used a half round file to make a groove for it to sit in.the big gear has a spindle that goes through to the film spool. i kept the cogs that turn the sprocket gear that guides the film. same blowtorch glue method for motor, and 5 minute epoxy for the cog to spool. will sort out the motor cog later as its a loose grip. also glued piece of metal over hole in top of camera strapped up and covered in sticky stuff

car body filler used to reinforce motor placement, and filling gaps and generally trying to make the thing look like one piece of equipment. i used lots of hardener maybe triple what instructions say. cuts down the smell,(toxic) also when its setting it gets warm at that point it can be trimmed and carved into nice shape with a large scalpel, work quick!

i wanted a full height slit, covering the sprocket holes. so some dremmeling with the fiber disk, its the fastest attachment for them like mini angel grinder disk, goggles. i read that drink can make good metal for slit . i tried but it was a bit rubbish instead i had some aluminum from i dont know where , maybe a mm thick i scored with a scalpel and snapped it. used epoxy to get it in place and then body fillerd around edges

time to sort out the slidey cog on motor spindle , used a knob with a flat edge that matched the spindle, little bit of super glue when attached , then drill and tie with wire and bodyfiller it in , cant glue to spindle as it needs to slide up to rewind film.

modify and engrave the logo. drill hole in back for a shutter button and feed the wire down to motor speed regulator power supply , had to find a old style helios lend as the base is narrower than most,others get caught on the motor. get some temporary battery solution ,velcro strap action, nice.the feet allow it to stand up otherwise it falls on its face.time to run a quick test roll.and see what happens. used some kodak 200 colour neg film from poundland.

so some leftover parts, the test roll overexposed but visible,
aperture f2.8
exposure somewhere in the middle
film 200asa
daytime overcast outside
i forgot to cover lens whilst rewinding
film got caught halfway through, i think on the rough slit

polishing the slit so its nice and smooth first with finishing paper then wax and cotton thing on dremmel. also blasted the cogs and greased them to make sure no filings were getting in there

calibration.
8 teeth on sprocket gear ,
8 sprocket holes is 33 mm of film.
the slit is 0.68mm .
33 divided by 0.68 is 48.52941176
one turn of the sprocket gear is about 48.5 exposures
so if one revolution takes 2 seconds
2 divided by 48.5 is 0.0412371134 second exposure
OR 48.5 divided 2 is 24.25 which in camera time is 1/24

i was measuring the time for 10 revolutions and multiplying the length of film by 10 , this makes the values i get averages of 10 soo less error
did the same with the lights and wrote the numbers by the knobs at where they were set

to make the dials look a bit better, used the pic of the dials and made nice on computer , then printed with sticker printer, the idea being you harmonize the lights with passing objects then set the motor speed to the same number ,then guess an aperture and shoot.

a nice grip is a must with a camera as heavy as this, have some of millys leather http://cameramill.co.uk/shop/ its sticky back so just cut the shapes and stick.really flexible stuff and the sticky is strong.

battery box is a couple of tobacco tins glued back to back one i trimmed a bit shallower to make batterys snug,more blowtorch glue here, i cut a hole in the bottom of the tins b4 gluing. also added a main on off switch.and remote socket for the shutter witch uses the same remote as my spinner mod.a mono 3.5mm jack. i also used eyelets to make the wire holes look less shabby. hot glue gun keeps the wires out of the way and protects from damage

finally i painted the bits of the tins that were not part of the colour scheme, not sure weather it was the best thing to do.used the red leatherette offcuts to cover more bits and stuck some black leather to the base.

whilst using i found that the wires between the door and the base are a bit short ,made loading difficult, so i extended them.the extra wire joins inside the battery compartment used more space do i had to grind the seam out a little bit the chuck was loose and i bent the bit, also added battery info inside.