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1 color reversal film, ISO 100. Reason: The color of color reversal film is true and not exaggerated. 100 degree membrane has fine particles.

2 The maximum flash synchronization file is 60, EV value is 7, ISO200, so the aperture value should be 2, the maximum you give is 2.8, and the flash index is 8,2 meters away, so the correct combination is: ISO200, flash, aperture 2.8, speed 15, which can ensure correct exposure. Attention should be paid to the following issues: tripod should be used when shooting.