Shutter-priority AE Shutter-priority AE (Tv), as every EOS owner already knows, is the opposite of the Av mode where the user chooses the shutter speed and the camera selects the appropriate aperture. With Program AE mode, the camera may not select the ideal shutter speed for the photos you have in mind, as in motorsports or other sporting events. As mentioned earlier, the P mode in all EOS models chooses the exposure settings based on the focal length of the lens used in addition to the overall brightness and ISO film speed used. With a 600mm focal length, the camera is more likely to choose a setting with a shutter speed of 1/640 sec., which may be appropriate to freeze action in certain sports but not that great for photos with panning methods in mind. In the Japanese GT racing photos below, the first photo was shot at 1/250 sec. at f/8 with the EOS-1N RS and EF 300mm f/2.8L IS USM telephoto lens fitted with Extender EF 2x. The pellicle mirror of the EOS-1N RS and its RS mode allowed me to capture the flame burst of the leading GT car as I was able to see it happening right before my eyes through the viewfinder! The next photo of Team Takata's Honda NSX was captured at a higher shutter speed of 1/500 sec. - panning method wasn't part of the plan but freezing the action was. Japanese GT in action Another of the GT cars     Slow shutter provides a sense of motion Panning is less apparent here but the wheels are not frozen For 500cc bike GP action, French rider Regis Laconi (No: 55) was captured with the standard EOS-1N fitted with the older EF 300mm f/2.8L USM and EF 2x. The shutter speed was 1/160 sec. at f/5.6. Slanting the camera angle contributed to the sense of motion. For bike GPs, freezing the riders/motorcycles totally with fast shutter speeds makes for boring photos as the wheels will be completely motionless, making them look as though the riders are floating upright on air rather than speeding down the track The close-up photo of Brazilian rider Alex Barros was captured with the EOS-1V and the EF 300mm f/2.8L IS USM w/EF 2x. The lens' IS Mode 2 allowed me to pan Barros, using a slower shutter speed of 1/200 sec. despite the 600mm focal length. However, the tight angle of this photo made the panning method to be less apparent as compared to the one with Laconi. But at least the wheels on Barros' bike were not frozen. In Program AE mode, with a 600mm focal length (300x2 or true 600mm), this combination would have made the EOS camera choose a shutter speed of 1/640 sec if the lighting conditions had permitted. At this shutter speed, you will not get wheels in motion but frozen ones instead. << Back to Main . 1 . 2 . 3 . 4 .