Why do older camera lenses have faster F-stops?

Started Apr 14, 2013 | Discussions thread
Allan Olesen
Senior MemberPosts: 2,207
Like?
Re: f1.8 equivalents...
In reply to EinsteinsGhost, Apr 18, 2013

EinsteinsGhost wrote:

Allan Olesen wrote:

EinsteinsGhost wrote:

Allan Olesen wrote:

It depends on your definition of exposure.

If exposure means "total amount of light reaching the sensor" then exposure will be different at same f-stop, same shutter speed and different sensor size.

If exposure means "amount of light per unit of sensor area" then exposure will be the same at same f-stop, same shutter speed and different sensor size.

As far as I know, the last definition is correct - which actually makes exposure irrelevant as a comparison parameter when comparing cameras with different sensor size.

What matters in such a comparison is the total amount of light reaching the sensor, and you WILL have to calculate the equivalent f-stop if you want to know that.

Okay, let us work with facts, as in numbers. Take a baseline for FF.

Are you asking me to do work for you?

I'm asking you to back up your claims with factual information, that demonstrates the few sentences you probably repeat every time on the subject.

I was trying to help by showing you two that your endless "Yes, it will" / "No, it won't" fight could end much faster if you first tried to understand what the other party meant by "exposure".

The need of agreeing on definitions before discussing consequences or results is not a claim. It is just common sense.

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