Indice de lumination!!! IL,EV ? pour que ce soit plus clair... |
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retour à la page d' ACCUEIL |
Tableaux de correspondances vitesses et diaph |
La profondeur de champ par l'exemple |
Les formules de calcul de la profondeur de champ |
Les indices de lumination |
On utilise les IL pour indiquer les limites de couplage des systemes de mesure et des systemes autofocus
des boitiers modernes.
Le tableau ci-dessous donne des valeurs d' IL en couples vitesses-diafragmes avec un film 100 ISO.
| IL/EV | f:2.8 | f:4 | f:5.6 | f:8 | f:11 |
| -1 | 15s | 30s | 1min | 2min | 4min |
| 0 | 8s | 15s | 30s | 1min | 2min |
| 1 | 4s | 8s | 15s | 30s | 1min |
| 2 | 2s | 4s | 8s | 15s | 30s |
| 3 | 1s | 2s | 4s | 8s | 15s |
| 4 | 1/2s | 1s | 2s | 4s | 8s |
| 5 | 1/4s | 1/2s | 1s | 2s | 4s |
| 6 | 1/8s | 1/4s | 1/2s | 1s | 2s |
| 7 | 1/15s | 1/8s | 1/4s | 1/2s | 1s |
| 8 | 1/30s | 1/15s | 1/8s | 1/4s | 1/2s |
| 9 | 1/60s | 1/30s | 1/15s | 1/8s | 1/4s |
| 10 | 1/125s | 1/60s | 1/30s | 1/15s | 1/8s |
| 11 | 1/250s | 1/125s | 1/60s | 1/30s | 1/15s |
| 12 | 1/500s | 1/250s | 1/125s | 1/60s | 1/30s |
| 13 | 1/1000s | 1/500s | 1/250s | 1/125s | 1/60s |
| 14 | 1/2000s | 1/1000s | 1/500s | 1/250s | 1/125s |
| 15 | 1/4000s | 1/2000s | 1/1000s | 1/500s | 1/125s |
| 16 | 1/8000s | 1/4000s | 1/2000s | 1/1000s | 1/500s |
| 17 | -- | 1/8000s | 1/4000s | 1/2000s | 1/1000s |
| 18 | -- | -- | 1/8000s | 1/4000s | 1/2000s |
| 19 | -- | -- | -- | 1/8000s | 1/4000s |