Archived posting to the Leica Users Group, 2014/04/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Is this really correct? A grain of film is a digital ( exposed or not exposed)? How would you then get differing grey levels in the same small area? All the grains in that area would all be exposed or not exposed.... Closer to the concept of printing..... I believe that a grain sensor within film is in itself an analog item with varying degrees of "greyness". To your point, you are speaking of quantization levels not individual pixel locations....... example.... Original D1 camera had 5MP of resolution. That meant there were 5milliion sensor locations. Each sensor location is recorded at (let's say) 14 bits of depth. A D4 has 16MP of sensor locations and it too is recorded ( let's say) at 14 bits of depth...... The D4 has more resolution. They have equal quantization levels. Image receptors per square inch is independent of the depth to which those sensor locations are measured..... I only spoke of receptors per square inch..... Here we go again... too much retirement time..... Frank Filippone Red735i at verizon.net But surely a single grain in film is either exposed or not, whereas a pixel has, depending on the sensor, thousands of brightness levels. So they are not directly comparable and it would require a big patch of film containing thousands of grains to display the range of tones a single pixel is capable of, though clearly a patch of pixels would be required to compare the effect. >________________________________ > From: Frank Filippone <red735i at verizon.net> >To: 'Leica Users Group' <lug at leica-users.org> >Sent: Saturday, 12 April 2014, 14:07 >Subject: Re: [Leica] Comparing film and digital resolution > > >Several years ago, I did the calculations based upon the molecular >particulate size of TMax100 film.? I picked that film because the >density data was available, and it was the most consistent particulate >size film available, and it was reputed to be the most consistent >homogenous density mix of crystals within the sensitive film layer. > >My assumption was that the TMax100 crystalline molecule was the >smallest discernible and quantifiable light capturing receptor.? >Therefore, the closest analogy to a digital sensor pixel. > >As I remember it, the particulate size, and therefore the effective >pixel density, was around 15MP per square inch.? The closest ( B+W >only) comparison is the MM. > >The MM is about 10MP per square inch. > >Based upon this, and for all practical purposes, digital sensor >technology resolution has caught up with chemical resolution. > >Too much time on your hands is a bad thing......you worry about things >that are purely theoretical.? This happened to me as well when I first retired. >Seems a pattern.... > >Frank Filippone >Red735i at verizon.net >