Subject | Re: ISO value names are becoming ridiculous |
From | Sandman |
Date | 01/06/2016 16:11 (01/06/2016 16:11) |
Message-ID | <sandman-e825f9d7f90ae9d6ad99f19b176259fe@individual.net> |
Client | |
Newsgroups | rec.photo.digital |
Follows | Whisky-dave |
Followups | Whisky-dave (1h & 59m) > Sandman Eric Stevens (11h & 33m) |
Because ISO is film sensitivity and sensor amplification, so it's only a variable for the resulting image.Whisky-daveSandmanSandmanWhisky-dave
So with the D5, it can boost its ISO to ISO 3,280,000, and suddenly how ISO is named is becoming just stupid. We should use EV steps instead:
SO why start at -1 ?
The base would be what is today called ISO 100, which corresponds to an expected brightness level of the resulting bitmap image.
Why limit it to bitmaps?
No, going from ISO 50 to ISO 100 is one full stop. The scale is arithmetic, remember. Each stop is a doubling of the value. ISO 100 is one stop more sensitive than ISO 50, just as ISO 800 is one stop more sensitive than ISO 400.SandmanWhisky-dave
So ISO 50 is one step lower than that, naturally.
not a 'step' but half I'd say.
Which is what I just said...Whisky-daveare you sure about that as it makes NO sense or is it nonsense. Doubling the ISO effectively doubles or makes it twice as sensitive to light meaing you only need half the exposure.Sandman
Which people understand when you talk about ISO 200 or ISO 6400 because those numbers are easier to understand.
I don;t remmeber having problems when I was exposing film at 10 ASA up to 6400 ASA
I doubt I'd have any trouble working out what 12,800Which is why it's only a problem now when we have ISO values of 3,200,000 and 4,000,000
would have meant either. which is why DIN or EV would be better than ISO as sensitivities increase as they do today.Which incidentally, is what I'm saying. In fact, the old arithmetic ASA standard had a logarithmic equivalent later called APEX which is very similar to what I am proposing, where APEX 5° = ASA 100 and APEX 6° = ASA 200 etc etc.
???Whisky-daveSandmanSandmanWhisky-dave
And the new D5 would have a max ISO value of "ISO EV+10" which can be pushed in-camera to "ISO EV+15", which would still be equally impressive.
EV values already have a meaning best not to change them.
Yes, and ISO can be part of the EV. So when changing the EV by using the ISO setting, it would be "ISO EV+4" for instance. Meaning that with "ISO EV 0", ISO is no part of changing the EV.
EV is for sensitivity really as it was the measure of the light level inside the camera not of the subject brightness.