Convert your Digital SLR to Infrared

We decided to use the safer specialist approach and sent our camera off to have some infrared surgery. Here's what happened.

We chose Advanced Camera Services in Norfolk who claim to employ trained technicians with many years experience in camera and camcorder repairs. The company have now set themselves up as camera modifying specialists with services to customise your digital SLR camera with Infrared, UV or Quartz filter conversions. They also supply cameras that have already been converted.

I decided to book my old Pentax *ist D in for a makeover, rather than sell it on eBay. Nearly two months passed before the camera was returned (they quote three to four weeks so I must have hit a busy patch) and it looked just like it did when I sent it, but under the hood was where the transformation lay.

For just over £200, ACS carefully strip your camera down, detach the ICF filter and replace it with an infrared glass that's the equivalent of the R72 filter. They use 720nm filter and should be offering an 830nm version in the near future. They also adjust the sensor position so the focusing point is shifted to correct for the infrared wavelength. At the same time they clean and service your camera as well as making exposure meter and shutter speed checks and adjustments. I had a problem with the mode dial not connecting to the correct modes and that problem was fixed, the mode dial is also now more positive to adjust. And the camera is returned with a six month guarantee.

So why go to this length and cost when you can shoot with a filter? As soon as I started using the camera the benefit is clear. I've used the *ist D with an R72 filter occasionally in the past and the exposure times of around 2- 6 seconds for a daylight scene are a real bind. Not only is it virtually impossible to shoot a subject with no movement, but it's also a pain waiting for the *ist D to process each shot as the buffer is slow on this camera, and you always have to carry a tripod. With this newly converted SLR the exposure times in similar conditions are up to 1/250sec.

The reason for this is that the ICF, also known as a hot mirror filter, blocks the IR part of the spectrum. To get a suitable exposure the camera's shutter needs to be held open long enough which, as mentioned, can be several seconds. With the ICF filter removed the infrared light is unblocked from the CCD and enables a fast shutter speed duration.

Another advantage is that the Anti-Aliasing Filter can also be removed, so the camera will take slightly sharper pictures although as this is in place to reduce moiré patterns you will see these present on subjects with close straight lines, such as a person's stripy suit or a ventilator grid.

The key benefit to in infrared conversion is that you can see through the lens just like a normal digital camera as the IR filter is on the CCD. So there's no guessing where the subject is. No prefocus. No constantly taking the filter off to compose the next shot. Just usual point & shoot methods.

Die-hard film photographers may be wonder about focus. Using infrared on film cameras meant you had to adjust the focusing using an IR mark on the lens This was because lenses are designed to bring blue, green and red (400nm to 700nm) colours into focus in the same spot, but Infrared light focuses at a slightly different point which results in a loss of sharp focus using a conventionally positioned sensors. As part of the modification ACS move the camera's sensor backwards to compensate for the infrared focusing point.

While on the subject of lenses it's worth noting a few characteristics of lenses. The sensor adjustment is made for a typical lens, usually the standard 50mm. Some lenses perform better or worse than this. Wider angle lenses may have out of focus corners and brightspots can occur where light has bounced off the image sensor and on the internal lens elements. These infrared hotspots are exaggerated at small apertures and on poorly coated lenses. You will usually find that two stops down is about the optimum setting, but it will vary. So if you have a range of optics, do a few trials to find the best lens and optimum aperture for the job.

ACS report that they have found the Sigma 10-20mm causes hotspots on Canon and Nikon cameras. I had no problem with the Sigma on my Pentax.

Use our article comments box at the bottom to add your favourite digital infrared lens and any other information you feel adds value to this article.

Finally infrared light records mostly in the red channel, so the camera will sometimes overexpose in this channel. You will see this on the camera's LCD at preview stage, so you can adjust the settings manually or shoot using the exposure compensation feature. Bear in mind that the amount of infrared light varies from scene to scene, even when the overall brightness is similar.

Tip
To get as close as possible to black & white try setting the camera's white balance to custom and taking a reading off white paper in the same light as the subject. Make sure the paper fills the frame when you take the reading.

It's adviseable to shoot in RAW mode as it provides a much better conversion to black & white when you process the shots.

I was considering selling my ist D but instead I now have a second body that can be used for my creative infrared work. I expect there will be less cameras for sale on eBay as this technique becomes more widely discussed

The camera was returned from ACS well wrapped in bubble wrap

A shot of Slatburn Pier and Tram car using the Sigma 10-20mm on the Pentax *ist D.

Saltwick Bay and Black Nab using the Sigma 10-20mm at 18mm on the Pentax *ist D.

Steam train at Pickering using the Sigma 10-20mm at 18mm on the Pentax *ist D

Sculpture at Clumber Park taken using a LensBaby 3G on the Pentax *ist D

Flesh goes whiter and eyes darker when shooting people. Taken using a LensBaby 3G on the Pentax *ist D

Old cable reel at Clumber Park taken using a LensBaby 3G on the Pentax *ist D.