Sigma SD14 ISO 50

SigmaChrome wrote:

xpatUSA wrote:

SigmaChrome wrote:

I shot lots of ISO 50 on the SD14. Once you understand how to manage the highlights, the results are simply stunning. Richer, finer grain; much like Kodachrome 64 and 25.

Examples here and below.

These shots are all well and good but I don't see any amazing differences in my test images other than the obvious -1 EV difference in sensor exposure of 100 ISO compared to 50.

The difference may not be "amazing" but it is significant and quite obvious - and that's all that matters to me.

When Sigma offered the firmware update offering ISO 50 and I applied it to my camera, the resulting shots were a pleasant surprise.

Following Sigma's Notes regarding using ISO 50 on the SD14 made good sense and produced excellent results, like these.

More to the point: Is there really any difference at all between an image shot at 50 ISO, 0 EC and one shot at 100 ISO and +1 EC? Assuming, of course ,that no sensor channels are blown or bottomed in either case.

Shooting at 100 ISO and +1 EC does not necessarily mean that any channels will blow. For example, in a scene with predominant highlights, the standard advice is to apply positive EC to avoid under-exposure of some shaded subject (the classic black cat on snow). The metering will try to render the scene average as mid-gray (about 13% on the sensor) and the poor cat could come out as a black blob buried in noise. Applying even +2 EC would expose that snow at about 52% on the sensor, about 189/255 in sRGB.

Since SPP applies a multiplier to account for the ISO setting (non-AFE cameras), a proper image comparison would involve equalizing the histograms in SPP before saving for comparison of image quality.

My bet is that the difference in IQ would be insignificant, with the claimed superior IQ at 50 ISO being due to the greater probability that a 50 ISO shot is more properly "Exposed-To-The-Right".

Regardless of your betting skills, most of us SD14 users here on DPR were very happy with the 50 ISO results.

OK. I fold.

[edit] What an amazing difference there must be between the SD14 and the SD1 Merrill !! A user of both gets his best results from the SD14 at ISO 50 and yet gets his best results from the SD1M at ISO 200. Quite remarkable . . [/edit]