Assertion: fp shutter | /r/HasAspect | noticeable speed error
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Source sentences:
text: Whereas the best mechanically controlled shutters were rated for 150,000 cycles and had an accuracy of ±¼ stop from nominal value (more typically 50,000 cycles at ±½ stop), today's best electronically controlled FP shutters can last 300,000 cycles and have no noticeable speed error.