I'd like to have an SLT-mirror that flips up during the shot

Started Oct 1, 2012 | Discussions thread
Shop cameras & lenses ▾
Allan Olesen Senior Member • Posts: 3,358
Re: Here are sample pictures with, and without an SLT mirror
3

Dirk W wrote:

I don't think you can calculate it that way because the ISO difference is not a linear function.

The ISO scale is linear. You need twice as much light to make the same photo at ISO 100 as you do at ISO 200. And 4 times as much at ISO 50.

So the ratio between two ISO values can be found by simple division. Then, if you want to convert that ratio into stops, you have to use logarithms.

Difference in stops: ln(ISO[1]/ISO[2]) / ln(2)

Simple math for anyone who understands it. Those who do not understand it just say "I don't think you can calculate it that way."

Post (hide subjects) Posted by
ck3
ck3
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow