What we discover at this cutoff is a digital image will appear sharper because there is no image pair contrast fall off. MTF is the way in.Ī 40% MTF contrast level is roughly 100 elements/mm resolution. It does no good to just say digital is different, we must form some standard of comparison because of this difference. Recalling the advantage that digital does not get 'fuzzy' in this sense, a cut-off point such as this is hardly objectionable in order to make a meaningful comparison. It has been suggested by others that 40% contrast point on an MTF chart is a good cutoff, a point after which fine detail, while still recognizable, is also starting to look fuzzy. If we accept this reasoning, we can say that a solid comparison to film would entail some type of an MTF cut-off point. It is only when we define resolution in terms of image contrast that we begin to have meaningful image quality comparisons. This is not true for digital, so even though film is said to 'out resolve' digital, we must be aware these resolution numbers alone were never the be all and end all of image quality. (As an aside, it is one reason why Fujifilm's 6圆 anti-aliasing design broke new ground.) After a point, the chemical process of film suffers from a rapidly dropping image contrast ratio as line pairs of resolution become narrow (the MTF). Their image contrast is always 100% down to the last image line pair, aliasing not withstanding. Simple answer, but what does this really mean?Ī feature of digital cameras that is different from film is electronic sensors are discrete devices. This is because of the low image contrast ratios at which film's supposed fine detail resolution advantage occurs. What we discover is we really cannot recognize this fact subjectively in a print.
In fact, only some low ISO films have more resolution than 2016 "digital" cameras, not many, just some. This statement hides a very important difference between film and digital images. To completely out resolve the best films, we need roughly 150 line pairs/mm, which is about 35 MP for APS-C, 80 MP for 35FF, 280 MP for 6圆. On the face of it, the news is pretty grim. Or, at least to asking myself questions.Īt what point on the MTF (Modulation Transfer Function) does film resolution overtake digital resolution? Could any film other than Kodachrome 25, a grainless, dye transfer process, still meaningfully out resolve digital in lines per mm pairs? And at more than ISO 25? And, sort of like scratching an old wound, it got me to thinking. Yet, we still read resolution numbers of Kodachrome and some panchromatic films that are much better than even today's sensors.
Then, why on earth did I abandon film with the first 4 MP digital camera I could get my hands on? Even more questionable, that I shot at 4 MP for over a decade? Or, sin of sins, that I have submitted to this very forum a couple of images taken with that 4 MP camera to make some technical or esthetic point with no one the wiser? I must have been completely out of it!
Often I learn something in doing this.įor twenty years I have read that film has more resolution than digital, and often to the effect that it always will. When comments appear that run counter to my experience of the real world, I often ponder why my impression might be invalid or in some way lacking insight.