Nicci78 a écrit :
Je me demande bien comment on règle le Q2 sur 2491 ISO...
il n'a jamais ete question de ca , il faudrait au moins lire correctement leur maniere de calculer la valeur ISO
https://www.dxomark.com/dxomark-camera- ... es/#sportscitation :
score: Low-Light ISO
To compensate for the lack of exposure, photographers have to increase the ISO setting, which results in a decreased signal-to-noise ratio (SNR). How far can ISO be increased while maintaining decent image quality? The DxOMark low-light ISO metric will give you this information.
The SNR indicates how much noise is present in an image compared to the actual image information (signal). The higher the SNR value, the better the image quality, as detail is not drowned out by noise. The SNR is given in dB, which is a logarithmic scale: an increase of 6 dB corresponds to doubling the SNR, which in turn equates to half the noise for the same signal. A SNR value of 30dB means excellent image quality. We have therefore defined low-light ISO as the highest ISO setting for a camera that allows it to achieve a SNR of 30dB while keeping a good dynamic range of 9 EVs and a color depth of 18bits. A difference in low-light ISO of 25% equals 1/3 EV and is only slightly noticeable. Low-light ISO is an open scale.
C'est un petit peu different des delires de chacun non ?
Nicci78 a écrit :
C’est juste un calcul mathématique. Rien de réellement probant. Car au lieu d’analyser un bête chiffre. On devrait regarder la courbe..
et c'est quoi la courbe sinon un bête chiffre mis en forme
ces bêtes chiffres ont l'intérêt d'éviter les délires sans fondements de chacun sur les forums