D
David Paul Carr
Guest
Like many others, I suspect, I have been looking at the Sigma DP1.
My calculations suggest that, to obtain the same depth of field I get with my GRD II at f2.4 I would need to stop the DP1 down to f6.7 ( DOF of approximately 1.8m -> infinity). What's that? Three stops difference? The difference between 100 and 800 ISO?
I have been experimenting making big inkjet prints from GRD II files, 80 cm on the short side at 200 DPI. This requires an interpolation of 230% and works pretty well. To obtain the same interpolated output size from the DP1, I need to increase the file size by 357%. Tests with downloaded sample files suggest that this is simply too much and that there is just not enough native resolution to allow such enlargements.
Maths is not my strongpoint but it seems to me that, at least as far as resolution and DOF field goes, the DP1 is not going to be a "GRD II killer" as I have seen it foolishly called elsewhere. Have I got this right?
My calculations suggest that, to obtain the same depth of field I get with my GRD II at f2.4 I would need to stop the DP1 down to f6.7 ( DOF of approximately 1.8m -> infinity). What's that? Three stops difference? The difference between 100 and 800 ISO?
I have been experimenting making big inkjet prints from GRD II files, 80 cm on the short side at 200 DPI. This requires an interpolation of 230% and works pretty well. To obtain the same interpolated output size from the DP1, I need to increase the file size by 357%. Tests with downloaded sample files suggest that this is simply too much and that there is just not enough native resolution to allow such enlargements.
Maths is not my strongpoint but it seems to me that, at least as far as resolution and DOF field goes, the DP1 is not going to be a "GRD II killer" as I have seen it foolishly called elsewhere. Have I got this right?