35mm adapter
2008
adapts 35mm minolta xg 9 still film camera to canon powershot sd400 digital camera. this way, you can take pictures, but more importantly, video with the lovely quality of a 35mm depth of field. this adapter keeps getting revised to become progressively better. not much has changed except a few lenses and casing modifications since the last version. plus the more common spelling of adapter. there is an increasing demand for 35mm video. the adapters available right now, like the letus35, redrock m2, rng35, are meant for video cameras, not digital point-and-shoots. what i love about my system is the size. because i'm using a point-and-shoot, the entire system is about the size of two minolta xg 9 cameras. i admit the quality is not as high as a good video camera with the afore mentioned adapters, but my camera is light and portable.
this is the back of the adapter.
to build this, i bought a 35mm film camera (at a thrift store with 3 lenses for $20!). i ripped out the shutter, and stripped it down to nothing but a lens holder essentially. i then bought a focusing screen (nikon f3 d-type) to put in the spot where the film would normally be. now normally, we would focus on that screen with the digital camera and call it a day, but since the canon powershot sd400 , and i assume most or all other point-and-shoots, cannot zoom and use macro simultaneously, i had to build an optical system for handling this problem. with the introduction of the lens you see in the image above, now i can zoom in and it takes care of the macro focusing. there is one more piece of glass in there, hidden right in front of the focusing screen. this lens helps to reduce vignetting. with all of this extra glass, yes there is light loss, but the image sharpness and focus are more important.
here is an unprocessed sample video, to showcase the adapter, of a guy doing a george w. bush impersonation. he came up to me on the street and asked me to film him.
here is a list of videos that i have shot with my 35mm adapter system:
ana
goodnight caterpillar - snail in the wrong shell music video
a cinematic representation of incrementally increasing beats per second
untitled
a tape in the life of
stills look decent but not as good as a digital slr. you can find some examples down below in the text for previous versions of this adapter.
older versions:
35mm to digital adaptor
2007
adapts 35mm minolta xg 9 still film camera to canon powershot sd400 digital camera. this way, you can take pictures (or video footage (is it meterage in europe?)) with all the lovely qualities of a 35mm look.
this diagram shows all the glass needed: a focusing screen (nikon f3 d-type) for the minolta xg 9 lenses' light to be projected onto. a convex lens with appropriate curvature to attenuate vignetting. and a magnifier, ripped out of a video camera viewfinder, to bring the image into full frame (and it helps with focus too). normally, all the spaces between lenses (above) are sealed off so no light can come in from the sides. but they're pictured open for demonstration purposes.
here's an example of how it looks (slightly processed: upped contrast, warmed a little bit, and a good technique of correcting chromatic aberration that brendan bellomo came up with):
me holding hose crank
2007
"truth be told, the focus is not perfect, but it's good enough for me. i plan on using this mostly for video anyway." - japhy riddle, before july 22, 2007. focusing issue has been fixed. it's now much sharper. however, the picture above has not been updated with one with better focus, and it won't be because i like the picture. hey, but if you would like to see a demo shot showcasing the quality, download this.
here are some videos that i used this invention on:
ana
goodnight caterpillar - snail in the wrong shell
a cinematic representation of incrementally increasing beats per second
it took a few tries to get this adaptor right (and it could still be improved probably). it all started like this: my goal was to somehow decrease the depth of field for my digital camera. i didn't know anything about optics. i started out by buying a minolta xg 9 camera with three lenses all for $20 at savers. when i looked through the viewfinder in the store, the depth of field was very shallow. so i bought it. what a score. this nice practically unused camera with three lenses for $20. at first i was shooting through the viewfinder:
anya petrashen looking like a model
2007
the minolta xg 9 uses a focusing screen with a split screen rangefinder and microprism ring variation. while these tools are useful for focusing, they end up in all the shots. for instance, in the one above, you can clearly see them. they're even more prominent in shots with less light or when the center of the frame is not the area in focus. i still took many photos this way, photoshopping some to remove the markings on the focusing screen. the tony montoya video was shot this way. i even made a cute little mounting system out of popsicle sticks and various nuts and bolts:
but i really needed better.
i ordered a nikon f3 d-type focusing screen because it has no markings on it. i removed the shutter from the back and placed it where the film would go. when i tried to shoot it with my digital camera, i was unpleasantly surprised to discover an intense amount of vignetting. so i looked at the original screen that came with minolta xg 9 and noticed that it has a very fine fresnel pattern on one side. a focusing screen free of markings and with a fresnel pattern is very hard to find. brendan bellomo, who had basically done this 35mm adaptor process before, showed me a screen that fit my requirements: the mamiya sa402 focusing screen. it normally runs for around $60, but i was fortunate enough to find one on ebay for $10. i won the auction of course. (whilst waiting for it to arrive, i built this). however, when i received the screen in the mail, i found it to have a circle in the middle of the screen. nooo! luckily, it's length was a little more than twice as long as the width i needed... basically, i cut it in half (possible because it was plastic, not glass). cutting this screen was pretty difficult because it was such a precision job, and was almost impossible due to restriction of the human eye. i used a very small circular saw blade attachment for a drill. if i used two eyes to look at what i was doing, i was faced with the difficulties caused by parallax. and if i used one eye, i had no depth perception. anyway, i just did the best i could and it turned out okay (i actually had to do it twice because the first time i measured wrong. but better to not cut off enough than to cut off too much). after i mounted it, i realized that i had to shoot down on it -- off axis, because it was now half of a fresnel lens. this added perspective distortion when shots were taken. i took a few shots with this system but scrapped it shortly. and the screen ended up getting scratched because it was plastic. this system did have a neat look to it though:
you can't tell on these pictures that easily, but the focusing ability was pretty bad. the off-axis mounting system was clever:
i did more experiments and found that a fresnel surface, specifically, was not needed to decrease vignetting. rather, any convex lens with the right curvature would do just fine. the best one i had was being used for my ray gun-like creation, the depth of field attenuator. as well as the nikon focusing screen that i had bought originally. you know what that means. r.i.p. depth of field attenuator. i ripped both of those out and sent them to a better place. the picture above shows the off-axis mounting system in place but, after i removed the mamiya screen.
so, with that, i was now using the nikon f3 d-type (again) and a convex lens rather than a fresnel one. this brings us to the top of this page and to the end of this story.