The title isn't strictly appropriate. There's no reason digital photography should imitate film, and rarely does it successfully. It often does so by the introduction of false elements like artificial grain. Also, there's no default film look to copy. That said, there are certain consistent difference between colour negative film and digital colour photography that can be overcome in post. The following are my observations, and it would be interesting to hear how other photographers tweak their Raw files to get something more pleasing.
The lens: modern lenses are very sharp and mostly highly corrected, sometimes in camera. The quickest way of getting a vintage appearance is to swap the lens for something less sharp. Even highly rated heritage lenses have less sharpness and contrast when used on digital cameras, than their modern equivalent. Remember, smaller than full frame (35mm) cameras will provide a telephoto effect relative to focal length, and an equivalent shallowing of depth of field.
Default corrections: editing software normally provides optimising parameters of sharpness, colour saturation, contrast and other factors. Once applied, these will resemble the appearance we have come to associate with digital photography. Turn all corrections off to avoid the digital "look". Even "faithful" or "neutral" pre-sets sometimes contain corrections, make sure all parameters are set to zero. This will look flat and lifeless initially, but only add the qualities you require, not the ones the camera or software offer you.
Colour: the biggest difference between film and digital photography is colour rendering. We are not looking for absolute authenticity, even if such a concept was possible - we are trying to achieve something naturalistic, which is a different thing. Naturalism is an ability to interpret nature after the fact in a pleasing and consistent way, without obvious artifice. In my experience the difference between the two media is their handling of green, with other colours of secondary importance. Isolate the green element in the image, and dial green saturation down. Way down. Something closer to straw than grass is good. Once the dominant effect of green-ness is overcome, other colours can be tweaked upwards where necessary. Film greens were often cyan, and much lighter. Putting more orange-red in autumn leaves works, and skies and skin tone can be tinted to taste.
Black: after colour, black is the next biggest factor in a film look. Digital colour photographs lack black, an appearance emphasised by the fashion to recover shadows and exhaust detail. We're not looking for detail in shadows, or anywhere to an excessive degree. A well exposed colour film image had good blacks.
Sharpening: this is a question of taste. Film era shots often had sharp centres and much less sharp edges. Chroma was more of a thing, as was barrel distortion. I veer away from over-sharpened photographs, and avoid printing at a size where the difference shows.
Printing: a print will always say photograph in a way an on-screen file never will. Most of the attributes of modern cameras, enlargement size, sharpness, dynamic range, were not available with film or harder to achieve in print.
I could go on but that's enough for now. Agree or disagree?
The lens: modern lenses are very sharp and mostly highly corrected, sometimes in camera. The quickest way of getting a vintage appearance is to swap the lens for something less sharp. Even highly rated heritage lenses have less sharpness and contrast when used on digital cameras, than their modern equivalent. Remember, smaller than full frame (35mm) cameras will provide a telephoto effect relative to focal length, and an equivalent shallowing of depth of field.
Default corrections: editing software normally provides optimising parameters of sharpness, colour saturation, contrast and other factors. Once applied, these will resemble the appearance we have come to associate with digital photography. Turn all corrections off to avoid the digital "look". Even "faithful" or "neutral" pre-sets sometimes contain corrections, make sure all parameters are set to zero. This will look flat and lifeless initially, but only add the qualities you require, not the ones the camera or software offer you.
Colour: the biggest difference between film and digital photography is colour rendering. We are not looking for absolute authenticity, even if such a concept was possible - we are trying to achieve something naturalistic, which is a different thing. Naturalism is an ability to interpret nature after the fact in a pleasing and consistent way, without obvious artifice. In my experience the difference between the two media is their handling of green, with other colours of secondary importance. Isolate the green element in the image, and dial green saturation down. Way down. Something closer to straw than grass is good. Once the dominant effect of green-ness is overcome, other colours can be tweaked upwards where necessary. Film greens were often cyan, and much lighter. Putting more orange-red in autumn leaves works, and skies and skin tone can be tinted to taste.
Black: after colour, black is the next biggest factor in a film look. Digital colour photographs lack black, an appearance emphasised by the fashion to recover shadows and exhaust detail. We're not looking for detail in shadows, or anywhere to an excessive degree. A well exposed colour film image had good blacks.
Sharpening: this is a question of taste. Film era shots often had sharp centres and much less sharp edges. Chroma was more of a thing, as was barrel distortion. I veer away from over-sharpened photographs, and avoid printing at a size where the difference shows.
Printing: a print will always say photograph in a way an on-screen file never will. Most of the attributes of modern cameras, enlargement size, sharpness, dynamic range, were not available with film or harder to achieve in print.
I could go on but that's enough for now. Agree or disagree?