How to use the really old-style stop-down metering style (display shows something other than “00”).[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]If you attach a non-EF lens to your older Canon EOS film camera, the camera notices that the lens doesn’t have a working computer and goes into stop-down metering mode. It nonetheless displays a full range of apertures, which you can set from 1.0 to 32.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Set the camera’s aperture setting to 1.0 and leave it there.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Do not set the camera’s aperture value to match that of the lens. In fact, I don’t know why the camera lets you change the aperture setting at all, since it only screws things up by overexposing the image.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]If your lens has an adjustable aperture (usually an aperture ring on the barrel) you must do the adjustment on the lens itself, not the camera. This will obviously vary the amount of light entering the camera. The camera reads it and meters from that accordingly.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Now, since the camera isn’t capable of adjusting the aperture setting on the lens it can’t work in P (program), Tv (shutter speed priority) or PIC (icon) modes with such a lens, but it’ll work just fine in Av (aperture priority) and M (manual) modes.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In Av mode you set the lens aperture using the lens aperture ring and the camera’s aperture setting to 1.0 and then camera will set a shutter speed automatically. In M mode you set the aperture using the lens aperture ring and then set the shutter speed on the camera yourself.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]One other note - some older EOS cameras have the annoying inability to remember aperture settings when you switch from one mode to another. Some models, such as the EOS 620/650 or 10/10s, automatically switch the aperture value to 5.6 whenever you go into Av and M modes. Since the aperture value must be set to 1.0 when using stop-down metering and a manual lens you have to dial the aperture back every single time you enter either mode. This is particularly annoying in M mode, because since these cameras lack a rear command dial you have to hold the partial metering button whilst rotating the main dial. Oh, well.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]How to use the new-style stop-down metering style (display shows “00”).[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]If you attach a non-EF lens to your newer Canon EOS camera, the camera notices that the lens doesn’t have a working computer and goes into stop-down metering mode, displaying the aperture value 00. This means that the camera knows that the aperture setting is not under its control and will not let you set the aperture electronically. This metering style makes a lot more sense than the old method.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]If your lens has an adjustable aperture (usually an aperture ring on the lens barrel) adjust it now. This will obviously vary the amount of light entering the camera. The camera reads it and meters from that accordingly.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Now, since the camera isn’t capable of adjusting the aperture setting on the lens it can’t work in the Tv mode with such a lens, but it’ll work just fine in the other “creative” modes - P (program), Av (aperture priority) and M (manual). It doesn’t really make sense to use the lens in any of the PIC (icon) modes.[/SIZE][/FONT]
Set the aperture using the lens aperture ring and the camera will set the correct shutter speed in all other modes except M, where you’ll have to set the shutter speed yourself. Generally, Av mode is probably the most convenient.
