Do you need to wear spectacles or have you got to the age when they are becoming a necessity? Shooting whilst wearing spectacles can prove tricky but there are a number of solutions for those photographers with short or long-sight.
All of Canon’s EOS range of SLR cameras feature a built-in dioptric adjustment system that allows photographers with less than 20:20 vision to get viewfinder clarity despite their eyesight defects. Ideally it should be the first adjustment that you make when setting up a new camera.
Dioptric adjustment allows for fine-tuning of the viewfinder focus to suit an individual’s eyes. The process is essential to ensure that both the image on the focusing screen and the viewfinder display information are in perfect focus.
Tucked in behind the rubber eyecup, close to the viewfinder on the latest EOS digital cameras, the small dioptric adjustment dial is easily overlooked. To access the adjustment dial, remove the rubberised eyecup. This is best done by squeezing both sides together firmly between finger and thumb and then pulling carefully upwards. The eyecup is held in place by two small latches. If it does not come free easily, it may need a little more pressure, lower down, on either side of the eyecup, before pulling upwards. Sometimes pushing upwards on the base of the eyecup with an index finger may help to bring it away from the viewfinder.
Once the eyecup is out of the way, the adjustment dial is clearly visible. Closer inspection reveals that the dial has a centre point marker that aligns with a line on the camera body. At this point, the adjustment is set to the default -1 dioptres. Above and below are indicators of + and – and the adjustment range is from +1 to -3 dioptres.
Adjusting the setting
Canon recommends that dioptric adjustments are made using your normal spectacles. Some may prefer to use their camera without them, however the process is the same.
Remove the lens and point the camera at a bright, but diffused light source such as a window. Removing the lens ensures that you concentrate on getting the focus screen in perfect focus. This is the surface where the camera mirror projects the image that you are capturing. If your view of the focus screen is not correctly adjusted, the image may appear unsharp, even if the camera is focusing it correctly.
Move the dioptric adjustment dial backwards and forwards until the focus point and other markings on the screen appear sharpest. Check that the viewfinder information displays are also sharp and also in perfect focus. The eye has an impressive compensatory ability for subjects that are not quite in perfect focus so it may be worth repeating the process a couple of times to ensure that results are consistent.
You are finished with on-camera dioptric adjustment. Replace the lens and ensure that when your camera autofocuses the image appears clear and crisp.
Canon Dioptric Adjustment lenses
If you’ve turned the camera’s built-in dioptric adjustment dial to its extremes and the screen is still not in sharp focus, fear not. Canon offers a range of dioptre adjustment lenses that extend the adjustment range from +4 to -7 dioptres.
The Dioptric Adjustment Lens E range has 10 different strengths and it helps to provide near and far-sighted photographers with a clear viewfinder image without wearing spectacles.
These lenses are available in graduations of 1 dioptre and provide the means to extend the range of adjustment built into the camera. The maximum lens available is marked -7 dioptres. It is, in fact, -4 dioptres, but it extends an EOS camera’s built in -3 dioptres range to -7. If you suspect that you may need an additional dioptric adjustment lens, it is worth checking with your optician and establishing the exact value that you require before ordering.
Dioptric lenses are mounted onto Canon EOS DSLRs behind the viewfinder using a rubber frame that needs to be ordered in addition to the lens. These frames are designated Eb, Ec, Ef or Eg depending on the camera model. To ensure that you order the correct one, check the system map for your camera in the instruction manual. Also, note that it’s important not to confuse these rubber frames with the Eyecup Eb, Ec, Ef or Eg options that will come with your EOS DSLR camera as standard.