Create your own IR filter
A digital camera sees more infrared than we do, and all you need to do to capture it, is to block out all the visible (non-infrared) light. You can buy filters that do this, but they can be ridiculously expensive – and buying stuff removes all the fun of creating stuff, n’est-ce pas?
The trick? In order to be able to withstand the heat on projectors, slide film will be created so it lets through infrared light, even past the portions of the slide that are completely black. In other words: Unexposed, developed slide film can be used as an IR filter!
Top tip: If your camera lens is bigger than 35mm film, why not just buy a roll of 120 slide film? It’s bigger :-)
More information about the hows, the whys, and the wherefores can be found on Wim Wiskerke’s website.
Where can you get developed, unexposed film?
1) Go into a camera store, buy a roll of slide film. (120 film is great, because it has larger surface area and no sprocket holes). If you can get film that is out of date, it’s cheaper. They may even give you a roll or two for free.
2) Hand the newly aquired roll of film back to the salesperson behind the counter, and tell them to get it developed. If they look at you in a confused way, explain why. Tell them to add a note on the film that yes, you know it is unexposed, and yes, you want it developing anyway.
3) Go back to the store 48 hours later, pick up your now-developed, still-underexposed slide film, which now is ready to be used as IR filter. The whole thing should cost you a fraction of the price of an IR filter!
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Insights, suggestions and comments
NO WAY!.
/IS GUTTED
i’ve spent about £30 on IR filters :S thats really going to bug me
I turned one of those cheep $30 Logitec web cams in to an inferred cam last year some time. It works really well (and confuses the heck out of lots of people)
“Exposed slide film can be used as an IR filter”
Erm… if it’s exposed does it not become no longer black? So you’d want “developed unexposed” slide film.
Good call, though! I’ve never got into IR photography… now’s my chance!
Stu: err, yeah, daft typo. Fixed – thanks for the heads-up!
I am going to go read the article but I remeber seeing someting on maybe say boingboing a year about about IR photography on Digital camearas but the story said that most of them today have IR blocking filters and circuits because it messes with the picture.
If this is true will these have to be removed before this will work or enchance the outcome?
Bah looked at the page for 3 seconds and answered my own question :P
Anyway as I happend to have my camera at work and a remote nearby the
Konica Minolta Z2 (mine was a model made in Japan) seems to pickup IR excellently.
Now… if only I can get ahold of some developed unxposed film.
Good !!! Good!!
If you want use Cokin or Lee Filter or other gelatine filter holder, you can use a sheet of 4×5 slide film (grosse format camera) cutting it .
Now, I ask you:
Is it possible to use this IR filter (from a slide film) directly on sensor of SRL camera having removed the its IR filter?
So I could take the pictures without get in and get out the IR filter in front of lens.
Thank you!
i dont know if i misunderstood something, but if you take a film and develope it unexposed you get black photo, but slide is negative so it’s white. i think you need overexposed film= white photo, black slide :)
(sorry for my english)
When slid film is developed, it is not a negative of the image.
Unexposed film = black
Overexposed film = clear
When slide film is developed, it is not a negative of the image.
Unexposed film = black
Overexposed film = clear
This is all very interesting but I’m looking for a way to block IR. I accidently broke the IR blocker on my camcorder now everything looks like hell. With the help of a little IR led I have a nifty night vision camera but I’m not too excited abou that.
Would such a filter block UV rays as well as visible? If so, pain sufferers could sunbathe with an IR filter shade (for cheap infrared therapy).
If I place this film over the lens of a flashlight will it act as an IR transmitter to enhance a night vision device?
dude… i tried this today and the guy in the shop thought i was a retard…
he wouldnt sell or develop the film for me until i explain what i need it for, but he was so retarded he couldnt understand.
anyways, i was so pssd off (~.~)”
could have shot him…
I have sony DSCW30 camera 6MP. Now To make IR filter,when i have unexposed developed film or negatives. How i use them on my camera. I mean how i attach and where. how big piece i cut.
Thanks
this works and is awesome, though i think it may have alot to do with what brand of sensor your camera uses. for the film, i got a roll of 120 velvia slide film for 50% off ($2.50), and they didn’t charge for processing since there wasn’t anything on the film!
I found I had to double the layering of the film for my camera. I have a k10d, used an old 50mm f1.7 fully manual pentax smc-m lens, camera in bulb mode shooting at iso 800 for 8-12 seconds on a tripod depending on the lighting. I just did it at lunch, so the images in camera are pink-red depending on exposure time (i shot in raw, but will try custom white balance next time i use it – lunch time is only so long!). anyways, i had been disapointed last night with a single layer of film over the lens – it was still transmitting the normal color spectrum, but with the added layer it works well, if not for the long exposure.
I was told using the surface of a floppy disk also worked.
I tried it and the images were REALLY feint and very red.
Does this occur with your film idea?
a question on slide film…
what if I have it processed under c-41…
I don’t know any lab here that can process e-6
Steef -don’t be silly, all labs will offer to process E-6, even if they have to send it to an external lab! If they don’t do it – or if they say they can’t, then start using a different lab, you don’t want to trust your precious photos to an amateur outfit like that!
I just finished mine here is my story.
I was up late lastnight and surfing the web when I stumbled on an Infrared video of the veins in some guys arm. I wanted to build my own.
I found a nother place that talked about the exposed negitive idea. So I looked all over the house and found an one inch length of film.
I grabed my sony digital video camera (tested it with a remote to see if it picked up IR) and taped the negative over the lens.
I worked.
I needed more exposted negative. I went to walgreens bought a roll of film opened the box and pulled the film out of the tube. Then asked the girl working to develop it for me. this was met with expected puzzlement, I told her what I was doing, that it was ok i only need the film.
I got home taped two pieces of the film to the back of my Nikon D50 lens. And went out side to test.
It worked so I tried 3 and 4 layers of film. 3 is darker and a little more crisp but 4 is really not worth it. 2 is a good number.
But it works so for about $5.00 I have my own IR filter.
i have some developed films with first portion of the film in black is it possible that i can use that as filter
yes you should be able to use that portion
I read a lot of these comments here, and I don’t think there is one serious photographer here. This idea does work, it’s a given, but why would you do it? Have you ever wondered why professional lenses are thousands of dollars? There are many reasons why, one of them is that it will give you quality/sharp more detailed image.
Adding film over, or even worse – taping it on the back of your lens, will only take away from the quality of your current lens, or it will slightly distort your image. “You” might not notice, but take it to a professional photographer and tell him/her what you’ve done.
IR filters can be expensive because those expensive ones will try to match and blend with the quality of your top of the line lens. That is why, there will be less or no distortion at all, and it will not take away from everything that your “top of the line” lens has to offer – if you use a real filter that was designed for you lens. (There are different lens/filter sizes.)
Adding this nonsense to your lens is like wearing the wrong glasses. You get your eyes checked once in a while, and if you need glasses, as you get older, your prescription will change, and your glasses will change optically. If you wear the wrong glasses your vision will be slightly distorted. Once you put the right ones on, you will notice the difference and will dispose the old ones. Your lens is your third eye, so wear the right glasses if you need so.
Lighten up GV. I didnt’ say it was a complete replacement for a decent IR filter – it’s just a starting point to see if you like the results! It’s a lot better than spending a small fortune for a couple of filters that you’ll never use again, because the technique leaves you cold, after all…
Perhaps there isn’t ‘one serious photographer here’, as you say, but as far as I can see, the rest of us haven’t forgotten that it’s meant to be fun…
I have found film to be pretty decent optically. It does deteriorate and is easily damaged… and who knows what actual wavelengths are being passed. I now use glass IR filters on the camera, but I still use developed unexposed film as IR filters on strobe heads… Makes the flash less obtrusive ;)
I’m a serious photographer (I don’t take myself too seriously though) I’ve put pieces of panty hose behind 20,000 dollar lenses (film) because it gave the right “look”… so there.
So would an overexposed B&W negative work?
Although your not saving money (may as well buy a R-72 or RM-90) you could use 5×4 sheet film, and that way it would fit over your flash too.
I will use it to look at women’s bras and bikini
Dear all
It is very interesting for me. This afternoon I’ve just got developed film for IR filter. But maybe i misunderstood, I went to camera shop, bought 1 roll of film, after that i requested them develope that film. But when got bach developed film, it looked like clear & red color. I try to take picture with that developed film cover and picture look like red filter (my camera is Canon 350D). I think I had mistake, before develope film, maybe i need to roll out film. This is correct or not, please instruct me.
Thank you and hearing from you soon
Is there a special developing process that follows the exposure?
Check the link above ( http://www.xs4all.nl/~oko/PICT0058.JPG ) for a picture taken with a cheap (EUR 45) digital camcoder with IR blocking filter removed and slide film filter installed in front of the lens. All operations took me half a day (for the first time) now I know how to do it it can be done in ~15 minutes. Film is not suitable for high resolution photography but does OK for snapshot phoography and (!!) IR video.
I have some posts on my blog about this IR with film technique.
Yes, the pictures turn out like crap doing it this way but, as one said here, its meant to be fun. Everyone can buy a IR filter, but only a few do it that way and have a true experience on doing something different from the crowd.
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I’ve been looking for a cheap IR filter and this looks great. Unlike GV I’m not concerned about image quality as I am hoping to use it over the built-in flash of a p&s digital camera to fire a SB26 off camera (it has a built-in optical slave). Anyone know if it would work?
Sorry, just to explain a little more. I want to place this cheap IR filter over the flash of the p&s. Take a photo with forced flash, have no visible light from the built-in reach the subject but enough IR light reach the SB26 to trigger it. Hopefully leading to a pleasing photo :)
Guys… I tried out with film… & even with the floppy…. & i even tried taking one of my old anaglyph(red blue) glasses… taking out both the colored gels.. & placing them on top of each other.. & placing them on my SONY HANDYCAM with NIGHT VISION on… & ITS WORKS WONDERFUL..
No matter what U r using.. film or floppy or anything… TRY USING IT WITH THE NIGHT VISION ON… & SEE THE DIFFERENCE…
“U CAN EVEN SEE THRU CERTAIN CLOTHING FABRICS & MATERIALS” The best way to see it is see ur SPEAKERS with ur cam…
Has anyone tried this over a Nikon on-camera flash used in wireless mode? I have a 3rd-party slave trigger that reacts on the pre-flashes no matter how I diminish the sensitivity. Wireless mode uses IR, and if the trigger uses visible light the bit of film might just be what I’m after.
TIA
Fuddlestack, it works – a friend of mine tried it a few days ago and boom! it blocks visible light (all the pre-flashes) and only IR goes to the flash unit. I’m thinking about it myself.
Hi All, I am in need of an IR filter to put in front of a 12 volt spotlight for security work.As black and white film is not available here,can i use unexpose3d X-RAY film and have it developed ( Thats to say if the x-ray department will agree ! )
Hi everyone-
Can someone tell me where to put the film on a cannon xs1000d? i have the exposed film(and yes the person at wal-greens thought i was crazy developing film right out of the box) Now im not sure where to put the film…Thanks to anyone who can help me out.
You need to put it on the lens – either in front (where the screw threads for the filter are), or on the rear of the lens (the bit that goes inside the camera) – if you choose to go down that route, then be really careful about how you mount it, as you don’t want your mirror to hit your bit of film.
Good luck!
“Congo Blue” and “Primary Red” stage light filters layered make a decent IR filter that rivals the pro lenses if put together right
I bought a roll of film, then I told him to develope that film. But when he gave me the developed film, it was clear. What happened? I also told him that the film should be unexposed, did he forget not to expose it? HELP :)
Ewald – did you buy a negative film by accident? You want a positive (slide / dias) film!
yes I bought a negative film. I’m not an expert in film photography (or something like that) so I didn’t know the difference between slide film and negative film, I googled the difference and now I know. I’ll buy slide film next time. Thanks a lot! I’ll be back with the feedback :)
Someone should write really big SLIDE FILM not NEGATIVE FILM for guys like me :)
slide film records the actual image in it’s dyes and emulsion ,normal film records a negative that is used to print ‘positives’ on photo paper. Unexposed slide film is no good as a filter as it still has layers of red/green/blue dye emulsion that have not been dissolved by processing.
Alright, from a professional photographer of 15+ years, there is absolutely nothing wrong with creating or modifying optical components on your own! Most professionals do some level of experimentation and home-brewing, we just know how to discern quality and chose what works. Try different blocking materials on the same sensor and see which ones have the least scattering/best IR transmittance. Refine it and share your results… ignore those who tell you not to use your minds and experiment.
does this work for a laser ir??? PLEASE REPLY SOON!!!
will it work if the slide film has been cross-processed?
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