Using an Canon ae1 slr with a hotshoe flash. Shooting birds in daylight, but shade of trees. Recently tried ISO 800 film. Lenses are FD mount Vivitar 70-210mm with Kenlock 2x teleconverter. The flash is Olympus T20 and it has manual mode with ASA (ISO) settings. Without flash the exposure is too dark with higher shutter speeds being hand held to reduce image blur. Idea is using higher 800 ISO film will lighten the exposure. What manual setting should the flash be on? is ASA 800 manual more or less flash? I am shooting generally at about 20-30ft. and flash might not even matter as it doesn't sync with higher shutter speeds. The problem I am struggling with is that of exposures being too dark. The teleconverter 2x makes it two stops darker. Can I compensate by setting my camera ISO to 400 or 200? Should the flash ISO/ASA match the camera? Ugggggg! The camera is near forty years old and using it for bird pics is really challenging...aperture, light metering, shutter speed setting and focus...all in a few seconds before the bird moves on!