ëSpeed is not the most important factor in camera equalization, consistency is. If a slow c amera h as extrem ely cons istent lag tim es it will be a better eq ualization
can didate than a faster but inc ons istent c amera. T he reas on wh y it is important to know the ap proxim ate fas test lag tim e for a c amera, es pec ially an inc ons isten t one, is to calculate margin of error (discus sed later in this section).
T he am ount of drift or lag tim e incon sis tency determines th e highes t sh utter s peed at which a camera will reliably equalize. The following table should be used as a starting point for testing purp oses only. Th e num bers in this table are bas ed on a 1/1 000 th or fas ter flash duration .
Sh utter S peed | Probable maximum safe |
| lag time variation for |
| average focal plane |
| (35mm) camera |
1/300 | <=0.0003 |
1/250 | <=0.0010 |
1/200 | <=0.0020 |
Probable maximum safe lag time variation for average leaf shutter cam era, F:8.0
<=0.0013
<=0.0020
<=0.0030
1/180 | <=0.0025 | <=0.0035 |
1/125 | <=0.0050 | <=0.0060 |
1/90 | <=0.0080 | <=0.0090 |
1/60 | <=0.0137 | <=0.0147 |
1/30 | <=0.0303 | <=0.0313 |
1/15 | <=0.0637 | <=0.0647 |
1/8 | <=0.1220 | <=0.1230 |
1/4 | <=0.2470 | <=0.2480 |
1/2 | <=0.4970 | <=0.4980 |
1 | <=0.9970 | <=0.9980 |
2 | <=1.9970 | <=1.9980 |
NLeaf s hutters have diff erent s hutter b lade travel times d epend ing on ap erture. A wider ap erture takes longer and reduc es the amou nt of varianc e allowed. A s maller aperture takes les s tim e thereby inc reasing the allowable variance. (A leaf s hutter s et to F:4.0, for example, may reduce the variance to the same as a focal plane camera).
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