Jonathan's blog

A while ago I shot some pseudo-infrared film: Ilford SFX 200. Unfortunately, being the impatient 6 year old that I really am, I didn’t fully read the data sheet.

The film is only sensitive up to 740 nm on a good day, while my filter only allows through wavelengths greater than 720 nm. Therefore, the film was almost guaranteed to be blank as hardly any light would get through.

Armed with this knowledge, I bought two rolls of Maco 820c which, as its name suggests, is sensitive up to 820 nm.

I also read a bit about how to meter properly when using an infrared filter. I set the ISO to 12 (the lowest my AE-1 will go). I attempted most of the photos 2 or 3 times, sometimes using the camera’s TTL meter with the filter on, and sometimes metering without the filter, then adding the filter and adding anywhere between 4 and 8 stops of exposure. In most cases the TTL light meter seemed to suggest about +7 stops, so I figured I was doing it about right.

I developed the film a couple of nights ago, and was disappointed to find it totally blank except for the one frame I’d shot without the filter. I hung it up to dry anyway, but then noticed that some ghostly images were appearing! I guess this means that I didn’t fix the film properly. Nonetheless, about half a dozen of the frames are showing underexposed images – which is progress. After about ten minutes the images stopped darkening so I moved them to a dimly-lit room to dry. I scanned them as quickly as possible, in case they disappeared again.

The negatives are massively underexposed, but the scanner was able to help a bit and I also used GIMP to boost the contrast massively. They look pretty awful and the grain is very coarse, but you can make out what the pictures are supposed to be if you look carefully. You can also see that much of the foliage is white, so I guess it worked

Some of the pictures also have fingerprints or creases, where the film got jammed while I loaded it onto my developing reel. It buckled and pinged out, and I had to poke it back in.

Here are some samples (published on this, my geek blog, rather than my photo blog, since I reserve the photo blog for pictures I actually like; and I consider these photos very much a scientific experiment!)

The Institute for Advanced Studies

Royal Fort House

Centenary Sculpture, Royal Fort Garden

Nathan in Royal Fort Garden

Incidentally, it’s now been a couple of days since I developed the film, and the images are showing no signs of fading further. Goodness knows what caused the magic appearing effect, then.

I still have one roll of Maco 820c remaining. Next time I will increase exposure by many, many stops. 15, perhaps. The camera’s longest shutter speed is 2″ so this will almost certainly put me in the region of bulb exposures and stopwatches.

If this doesn’t yield decent results I’ll stop buying infrared film, because it’s not cheap!

When I first started getting into photography a couple of years ago, I wanted to have a go at everything. I bought the cheapest infrared (IR) filter I could find on eBay and was delighted to find that my then camera, a Fuji S9600, was slightly sensitive to very deep red, and IR. I don’t think it was supposed to be, but it enabled me to take IR photos of outdoor scenes, and very hot objects, such as this light bulb.

When I traded in the S9600 for a Canon 450D, I was slightly disappointed to find that it wasn’t at all sensitive to the same range of IR and/or deep red. There are companies that will do an IR conversion, which involves taking the camera apart and removing its internal IR filter. It’s expensive, and it’s pretty much a one-way conversion.

Then I realised there was a cheap and practical alternative that had been staring me in the face the whole time. My 35mm SLR.

IR film is several times more expensive than regular film, but still vastly cheaper than digital IR photography. I bought a roll of Ilford SFX200 and it was about £8.

I read about how to correctly expose IR film and frankly it sounds confusing. Lots of people recommend using a light meter, but then you have to take into account the filter which is present on the camera but not on the light meter. It’s anybody’s guess how many stops you need to compensate for the IR filter.

It’s also a shot in the dark (no pun intended!) as to the ratio of visible light to invisible IR light. This varies with the time of day, what the light is falling upon, and about a million other things.

I wanted to shoot one or two frames, see the results, and then make sure I was doing it properly before shooting a whole film. Unfortunately that’s not easily possible, so I’m just going ahead and shooting a whole 36-exposure roll. As I write, I’m about halfway through the film.

The good news is that my Canon AE-1′s light meter appears to be sensitive to IR light. That is, with the IR filter on, the internal meter appears to work properly so I can simply use the camera as normal. I verified this with a quick back-of-the-envelope calculation to compare the meter’s behaviour with and without the IR filter. It seems about right.

So here’s hoping that this fantastic little camera will produce me 36 interesting IR photos. We will see – watch this space!

Filters are pieces of glass that screw onto the front of your camera, and they can cause all sorts of unusual effects to your photos.

The good news is that you can buy filters cheaply from eBay (and of course, less cheaply from the high street, if that’s how you like to buy). Before buying, you’ll need to know the diameter of your camera’s lens. This should be written somewhere on the lens barrel or often around the glass on the front of the lens. Look for something like Φ58mm, and then check that your lens has a fine screw thread inside the rim. You’ll need this for the filters to screw into.

Of course each camera (and potentially each lens, if you have an SLR) may have a different lens diameter. If you’ve built up a large collection of filters and you plan on changing camera, never fear! You can buy adapter rings that allows you to use the “wrong” size filters on your new camera.

So let’s have a look at the various kinds of filter you can buy. This list is by no means exhaustive!

These are the rules of thumb that I’ve come up with through experimentation. Hopefully they’ll be useful:

• Always keep a UV filter (or at least some other type of filter) on the lens to prevent scratches
• Consider replacing the UV filter with a Skylight filter when shooting outdoors to avoid a blueish cast
• Use an ND filter when shooting in very bright light to avoid overexposed areas
• Use a CPL or a GND when shooting landscapes with large areas of sky, to make the sky dark and rich
• Consider using a diffuser when taking close portraits to soften skin tones
• Any of the other filters are generally for novelty effects and are not subtle
• Try to use only one or two filters at any one time. Every filter you add can decrease the quality of the lens system, and if you stack up three or more filters, you can usually see the rim of the filters in the photo.

So if you fancy trying something different, I recommend getting some cheap filters from eBay and seeing what interesting effects you can come up with.

Next time, I will write about basic photo editing on a computer.