09-24-2011, 04:57 PM
[quote name='mst' timestamp='1316878864' post='11818']
That's all relevance the ISO number has to me as a photographer. Same ISO, same aperture -> same shutter speed. Regardless of the sensor size.
[/quote]
And by the way ... that's exactly what led to the apertures we use today ... f/2 ... rather than "50mm wide on a 100mm lens" ...
same f-number->same exposure time (on the same ISO).
To add one thing ... even in the film-days, the ISO-value of a film was never that fixed as it has
been claimed in this thread. You could always push and pull a film ... I used my Ilford HP5
that nominally had 800 iso luckily at 3600 iso.
That's all relevance the ISO number has to me as a photographer. Same ISO, same aperture -> same shutter speed. Regardless of the sensor size.
[/quote]
And by the way ... that's exactly what led to the apertures we use today ... f/2 ... rather than "50mm wide on a 100mm lens" ...
same f-number->same exposure time (on the same ISO).
To add one thing ... even in the film-days, the ISO-value of a film was never that fixed as it has
been claimed in this thread. You could always push and pull a film ... I used my Ilford HP5
that nominally had 800 iso luckily at 3600 iso.