Looking at film grain comparisons
Feb 14, 2024 14:28:37 #
Now that we've looked at a number of film emulsions (see links in Conclusion -- 1st reply -- below), let's do a comparison of the details of film grain.
INTRODUCTION
Wikipedia gives us this basic definition: Film grain is the random optical texture of processed photographic film due to the presence of small particles of a metallic silver, developed from silver halide. The optical effect of film grain -- and the magnitude of effect -- depends on both the film stock and the definition at which the grain is observed. The grain can be objectionably noticeable in an over-enlarged film photograph, much as digital noise is seen better at the 1:1 pixel-level details.
The image examples below use digital scans of 35mm negatives, with detailed insets showing the 1:1 pixel resolution of that section of the scan, overlaid to 2048px "resized" image files. This is done for discussion and online presentation of the topic.
Example 1
St Patrick's Parade by Paul Sager, on Flickr
DISCLAIMER
As mentioned above, this discussion uses examples that are digital scans of 35mm film negatives, then further edited in Adobe Lightroom. So, the 'film grain' seen at the 1:1 pixel-level is somewhat more (or less) than literal 'film grain'.
Another observation (disclaimer) is my own use of both (a) exposure adjustments and (b) colored filters that also impact a discussion of film grain. The observable grain in many of these scanned images is different than what I could find from images shot at the 'box speed' of the film without a filter.
A final disclaimer is to mention this discussion is intended to 'show' the film grain one might expect from various film times used in the annotates examples. Your exposure technique and / or the film developing process may produce more (or less) observable film grain. You can also process your digital scans differently, again keeping (or hiding) much of the observable film grain.
Example 1a, below, shows the format of the comparisons to be used in the remainder of this film grain discussion. The resized digital scan is overlaid with an extract of the original scan showing a more detailed view of the grain of TMAX 400, a tabular grain film we'll discuss in more detail.
Example 1a
TECHNICAL BACKGROUND - What causes film grain?
The size, shape and behavior of the silver halide grains, when exposed to light, play the crucial role(s) in the image characteristics of the resulting 'film grain' within the image. There is a tradeoff between the crystal size of the silver halide grains and light sensitivity (film speed); where larger crystals have a better chance to receive enough energy (light) to flip them into a developable state. Large crystals give more sensitive film, for the price of being visibly 'grainier' in the image. Fine grain better preserves details but requires more light.
'Film' is a photosensitive emulsion consisting of several layers of gelatin substrate that adhere to a structural base. These gelatin layers contain the “grains” of silver halide applied in a random suspension. The sensitivity of the film to light depends on the amount of silver halide present in the substrate. The emulsion and base acetate turn semi-transparent through the development process.
When a silver halide crystal is exposed to light (photons), a sensitivity speck on the surface of the crystal is turned into a speck of metallic silver (these comprise the invisible or latent image). If the speck of silver contains approximately four or more atoms, it is rendered developable - meaning that it can undergo development which turns the entire crystal into metallic silver. Areas of the emulsion receiving larger amounts of light (reflected from a subject being photographed, for example) undergo the greatest development and therefore results in the highest optical density.
Cubic vs Tabular grains
Today's film stocks, 35mm and larger, use either a 'classical' cubic structure or a more 'modern' tabular-grain. The cubic grain can be thought of as cubic grains of salt, although of more random sizes than the near uniform size of table salt. These cubic grains are actually more like random sized pebbles in a river bed, big pebbles and small pebbles all mixed together randomly. This random distribution of cubic-grain film emulsions provides a more "forgiving" film that is tolerant to a wider range of exposures. These 'cubes' range from small to large, when considering the relative 'size' of individual grains. The difference in higher ISO (more sensitive) film types is the proportion of relatively larger grains is greater, but still, the grains overall will range from 'tiny' to 'large'.
Tabular-grain films use crystals that are relatively 'flat', like floor tiles rather than cubes, with a width to thickness ratio of at least two, often more. This 'flat' shape allows for more overlapping of the crystals, reducing intergranular space and giving more 'surface' for the same amount of silver. Tabular crystals scatter the light less, giving a sharper image but with less gradation between dark (black) and light (white).
Example 2
USS Drum by Paul Sager, on Flickr
Since film grains are light-sensitive, exposure is all about the amount of light that hits the film stock via the lens aperture. The silver halides crystals of the film can become 'over-exposed' or 'under-exposed' based on the rate of transformation via photon exposure, that is: the light reaching each individual grain. Once developed, silver grains exposed to enough light to convert from halide to fluoride become a part of the final negative image. The development process washes away grains that did not receive adequate light for transformation. This leaves behind “gaps” where the grains once were present in the emulsion. It is the perception of these gaps that we refer to as the graininess of the image.
There are multiple factors that can impact the resulting film grain, including the exposure settings used (amount of light), the film grain type of the film, the selection of developing chemicals, and the developing process, such a time (duration), temperature and washing 'method' that removes the unconverted grains. This discussion looks at representative examples of film grain using commercial processing, making the development process and chemicals outside the scope of discussion.
FILM GRAIN vs DIGITAL NOISE
There is a clear difference between film grain and digital noise. Digital noise is interference that comes from a digital sensor, whereas grain is texture that comes from an individual stock of analogue film. Two very different things. Film grain is an inherent characteristic of film stock and cannot be eliminated, while digital noise can be reduced (or eliminated) through noise reduction techniques.
EXAMPLES
Each type of film stock had its unique grain pattern. These microscopic grains of silver halide define the film's sensitivity to light. Film grain adds a layer of texture that is often associated with a certain quality and richness that digital clarity sometimes lacks. Being unique to each film stock, grain also gives a visual 'identity' to each film stock. Film grain is part of the art form of analogue photography, both still images and motion pictures. Choosing your film stock can be an artistic decision. The examples below are intended to give some examples to better inform these decisions.
Example 2a
Kodak Tri-X has been around in one form or another for a very long time. It is Kodak's most popular Black and White film. The introduction of the 35mm and 120 formats in 1954 is commonly cited as the official 'birthday' of Tri-X. In 2007, Tri-X was extensively re-engineered, receiving the new designation 400TX in place of TX or TX400, and it became finer-grained. The amount of silver in the film stock was reduced during the 2007 re-engineering.
Example 3
EAA Oshkosh 2018 by Paul Sager, on Flickr
This early morning example probably best shows the 'fine grain' aspect of Tri-X 400, although the exposure data from the EOS 1v shows +2 EV, meaning the film was exposed effectively as ISO-100. We don't see any blown highlights; I checked for clipped highlights in Lightroom. There's lots of shadow detail in this high contrast view. The inset details in Example 3a show the details of this 'classic' cubic grain.
Example 3a
Tabular grain films were originally developed for color film. The technology, also called T-grain, was later transferred to B&W film. Tabular grain technology brought significant improvements to the image quality of the film, particularly in the improvement of resolution and granularity. When compared to cubic grain films, many tabular grain B&W films seem almost like digital conversions to B&W, rather than film, given the near absence of any film grain.
Example 4
2019 Cubs Home Opener by Paul Sager, on Flickr
The abbreviated term T-grain has become a bit of a catch-all to describe any tabular-grain films, but this is like calling any vacuum cleaner a Hoover. T-grain is what Kodak called their own tabular-grain technology, meaning the only real T-grain films, technically speaking, are its T-MAX ones. Popular black and white films using tabular-grain include the various speeds of Kodak TMAX, Delta films from Ilford Photo, and the recently re-introduced Fujifilm Neopan films.
Example 4a
Neopan was originally a family of black and white films from Japanese manufacturer Fujifilm. The range of speeds and formats now only comprises one film: Neopan ACROS 100 II, a tabular-grain silver halide black and white film re-launched in 2019 and currently sold worldwide.
Example 5
Chicago Theatre by Paul Sager, on Flickr
Most of my Acros II images show virtually no grain, especially where the frame includes some direct sunlight and I've 'added' exposure, such as +0.7 EV in this example image.
Example 5a
This final set of images attempts to show a similar subject, all in B&W, using different types of film. Alas, only two were even captured during the same calendar year. Three of the images use tabular-grain films, examples 6, 7 and 9, where example 8 returns to the cubic grain of Tri-X. Some of the images also include the use of colored filters and exposure adjustments. From the technical aspect of 'grain', all four images are remarkably similar as shown in the detail insets.
Example 6
Ilford Delta 400 with an Orange filter +2.3 exposure adjustment.
Cloudgate by Paul Sager, on Flickr
Example 7
Kodak TMAX 400 with +1.7 exposure adjustment.
Snowy Cloud Gate by Paul Sager, on Flickr
Example 8
Kodak Tri-X 400 with +0.7 exposure adjustment.
Cloudgate in Snow by Paul Sager, on Flickr
Example 9
Fuji Acros 100 II with +0.3 exposure adjustment.
Cloudgate by Paul Sager, on Flickr
Example 6a
Example 7a
Example 8a
Example 9a
INTRODUCTION
Wikipedia gives us this basic definition: Film grain is the random optical texture of processed photographic film due to the presence of small particles of a metallic silver, developed from silver halide. The optical effect of film grain -- and the magnitude of effect -- depends on both the film stock and the definition at which the grain is observed. The grain can be objectionably noticeable in an over-enlarged film photograph, much as digital noise is seen better at the 1:1 pixel-level details.
The image examples below use digital scans of 35mm negatives, with detailed insets showing the 1:1 pixel resolution of that section of the scan, overlaid to 2048px "resized" image files. This is done for discussion and online presentation of the topic.
Example 1
St Patrick's Parade by Paul Sager, on Flickr
DISCLAIMER
As mentioned above, this discussion uses examples that are digital scans of 35mm film negatives, then further edited in Adobe Lightroom. So, the 'film grain' seen at the 1:1 pixel-level is somewhat more (or less) than literal 'film grain'.
Another observation (disclaimer) is my own use of both (a) exposure adjustments and (b) colored filters that also impact a discussion of film grain. The observable grain in many of these scanned images is different than what I could find from images shot at the 'box speed' of the film without a filter.
A final disclaimer is to mention this discussion is intended to 'show' the film grain one might expect from various film times used in the annotates examples. Your exposure technique and / or the film developing process may produce more (or less) observable film grain. You can also process your digital scans differently, again keeping (or hiding) much of the observable film grain.
Example 1a, below, shows the format of the comparisons to be used in the remainder of this film grain discussion. The resized digital scan is overlaid with an extract of the original scan showing a more detailed view of the grain of TMAX 400, a tabular grain film we'll discuss in more detail.
Example 1a
TECHNICAL BACKGROUND - What causes film grain?
The size, shape and behavior of the silver halide grains, when exposed to light, play the crucial role(s) in the image characteristics of the resulting 'film grain' within the image. There is a tradeoff between the crystal size of the silver halide grains and light sensitivity (film speed); where larger crystals have a better chance to receive enough energy (light) to flip them into a developable state. Large crystals give more sensitive film, for the price of being visibly 'grainier' in the image. Fine grain better preserves details but requires more light.
'Film' is a photosensitive emulsion consisting of several layers of gelatin substrate that adhere to a structural base. These gelatin layers contain the “grains” of silver halide applied in a random suspension. The sensitivity of the film to light depends on the amount of silver halide present in the substrate. The emulsion and base acetate turn semi-transparent through the development process.
When a silver halide crystal is exposed to light (photons), a sensitivity speck on the surface of the crystal is turned into a speck of metallic silver (these comprise the invisible or latent image). If the speck of silver contains approximately four or more atoms, it is rendered developable - meaning that it can undergo development which turns the entire crystal into metallic silver. Areas of the emulsion receiving larger amounts of light (reflected from a subject being photographed, for example) undergo the greatest development and therefore results in the highest optical density.
Cubic vs Tabular grains
Today's film stocks, 35mm and larger, use either a 'classical' cubic structure or a more 'modern' tabular-grain. The cubic grain can be thought of as cubic grains of salt, although of more random sizes than the near uniform size of table salt. These cubic grains are actually more like random sized pebbles in a river bed, big pebbles and small pebbles all mixed together randomly. This random distribution of cubic-grain film emulsions provides a more "forgiving" film that is tolerant to a wider range of exposures. These 'cubes' range from small to large, when considering the relative 'size' of individual grains. The difference in higher ISO (more sensitive) film types is the proportion of relatively larger grains is greater, but still, the grains overall will range from 'tiny' to 'large'.
Tabular-grain films use crystals that are relatively 'flat', like floor tiles rather than cubes, with a width to thickness ratio of at least two, often more. This 'flat' shape allows for more overlapping of the crystals, reducing intergranular space and giving more 'surface' for the same amount of silver. Tabular crystals scatter the light less, giving a sharper image but with less gradation between dark (black) and light (white).
Example 2
USS Drum by Paul Sager, on Flickr
Since film grains are light-sensitive, exposure is all about the amount of light that hits the film stock via the lens aperture. The silver halides crystals of the film can become 'over-exposed' or 'under-exposed' based on the rate of transformation via photon exposure, that is: the light reaching each individual grain. Once developed, silver grains exposed to enough light to convert from halide to fluoride become a part of the final negative image. The development process washes away grains that did not receive adequate light for transformation. This leaves behind “gaps” where the grains once were present in the emulsion. It is the perception of these gaps that we refer to as the graininess of the image.
There are multiple factors that can impact the resulting film grain, including the exposure settings used (amount of light), the film grain type of the film, the selection of developing chemicals, and the developing process, such a time (duration), temperature and washing 'method' that removes the unconverted grains. This discussion looks at representative examples of film grain using commercial processing, making the development process and chemicals outside the scope of discussion.
FILM GRAIN vs DIGITAL NOISE
There is a clear difference between film grain and digital noise. Digital noise is interference that comes from a digital sensor, whereas grain is texture that comes from an individual stock of analogue film. Two very different things. Film grain is an inherent characteristic of film stock and cannot be eliminated, while digital noise can be reduced (or eliminated) through noise reduction techniques.
EXAMPLES
Each type of film stock had its unique grain pattern. These microscopic grains of silver halide define the film's sensitivity to light. Film grain adds a layer of texture that is often associated with a certain quality and richness that digital clarity sometimes lacks. Being unique to each film stock, grain also gives a visual 'identity' to each film stock. Film grain is part of the art form of analogue photography, both still images and motion pictures. Choosing your film stock can be an artistic decision. The examples below are intended to give some examples to better inform these decisions.
Example 2a
Kodak Tri-X has been around in one form or another for a very long time. It is Kodak's most popular Black and White film. The introduction of the 35mm and 120 formats in 1954 is commonly cited as the official 'birthday' of Tri-X. In 2007, Tri-X was extensively re-engineered, receiving the new designation 400TX in place of TX or TX400, and it became finer-grained. The amount of silver in the film stock was reduced during the 2007 re-engineering.
Example 3
EAA Oshkosh 2018 by Paul Sager, on Flickr
This early morning example probably best shows the 'fine grain' aspect of Tri-X 400, although the exposure data from the EOS 1v shows +2 EV, meaning the film was exposed effectively as ISO-100. We don't see any blown highlights; I checked for clipped highlights in Lightroom. There's lots of shadow detail in this high contrast view. The inset details in Example 3a show the details of this 'classic' cubic grain.
Example 3a
Tabular grain films were originally developed for color film. The technology, also called T-grain, was later transferred to B&W film. Tabular grain technology brought significant improvements to the image quality of the film, particularly in the improvement of resolution and granularity. When compared to cubic grain films, many tabular grain B&W films seem almost like digital conversions to B&W, rather than film, given the near absence of any film grain.
Example 4
2019 Cubs Home Opener by Paul Sager, on Flickr
The abbreviated term T-grain has become a bit of a catch-all to describe any tabular-grain films, but this is like calling any vacuum cleaner a Hoover. T-grain is what Kodak called their own tabular-grain technology, meaning the only real T-grain films, technically speaking, are its T-MAX ones. Popular black and white films using tabular-grain include the various speeds of Kodak TMAX, Delta films from Ilford Photo, and the recently re-introduced Fujifilm Neopan films.
Example 4a
Neopan was originally a family of black and white films from Japanese manufacturer Fujifilm. The range of speeds and formats now only comprises one film: Neopan ACROS 100 II, a tabular-grain silver halide black and white film re-launched in 2019 and currently sold worldwide.
Example 5
Chicago Theatre by Paul Sager, on Flickr
Most of my Acros II images show virtually no grain, especially where the frame includes some direct sunlight and I've 'added' exposure, such as +0.7 EV in this example image.
Example 5a
This final set of images attempts to show a similar subject, all in B&W, using different types of film. Alas, only two were even captured during the same calendar year. Three of the images use tabular-grain films, examples 6, 7 and 9, where example 8 returns to the cubic grain of Tri-X. Some of the images also include the use of colored filters and exposure adjustments. From the technical aspect of 'grain', all four images are remarkably similar as shown in the detail insets.
Example 6
Ilford Delta 400 with an Orange filter +2.3 exposure adjustment.
Cloudgate by Paul Sager, on Flickr
Example 7
Kodak TMAX 400 with +1.7 exposure adjustment.
Snowy Cloud Gate by Paul Sager, on Flickr
Example 8
Kodak Tri-X 400 with +0.7 exposure adjustment.
Cloudgate in Snow by Paul Sager, on Flickr
Example 9
Fuji Acros 100 II with +0.3 exposure adjustment.
Cloudgate by Paul Sager, on Flickr
Example 6a
Example 7a
Example 8a
Example 9a
Feb 14, 2024 14:29:11 #
CONCLUSION
So, what to say as a conclusion? I've spent several weeks looking at and for example images, and in the process of composing this post. I've recognized during this process that I look at the film grain of these images with the eyes of a digital photographer, returning to film in the 21st century with completely different eyes than maybe those who started with film in the past. I think too, I'm not alone in how I view and accept film grain. Each new film release, or updated formulation, seems to deliver a finer and finer grain structure, some now virtually grain-free.
In those final four examples, I see I approach exposing film in a way that seeks to minimize the resulting grain. This is done by reviewing the ideas of others and my own confirmation experiments. It's not that I don't want grain, rather, I don't want obnoxious grain, the type and level of grain that I seem to 'see' first, even before seeing the image.
From the people I seek advice from online, most everyone says to 'overexpose' your 35mm film. The minimum suggestion is a default +1/3 stop, whether you adjust the ISO speed or use exposure compensation. The idea is to give those silver halide crystals as much light as possible. Many sources suggest too to rate the ISO sensitively of various film stocks as different than the 'official' box speed. A film like Tri-X 400 I now load as ISO-250 and then just use neutral metering from the SLR camera. My EOS 1v automatically reads the canister DX code, so I just override the camera's 400 number from the DX code to 250 before starting to shoot.
Hopefully, you'll find this presentation interesting, if not actually helpful. As always, the images are scanned and then edited in Adobe Lightroom Classic, so the over-exposed results are even more different in the final edit than was captured from the camera. My personal B&W tastes seek a higher contrast, where I'm whitening the whites and darkening the darks in most every frame to achieve the results presented in these examples, beyond the effort to manage film grain.
I shoot 35mm, rather than larger formats. When I look at larger formats, especially B&W images, I tend to note the absence of film grain. Those larger format film types tend to use finer crystals, as more film surface is exposed to light as compared to a frame of 35mm film. I'm not trying for grain-free film photography, rather, just a result that minimizes the grain in the 35mm format I shoot.
Some photographers love the grainy look of film, because it adds texture, mood, and character to their images. Other photographers prefer a smooth look (less grain), because it enhances the clarity, detail, and realism in their images. I've come to appreciate the 'classic' graininess of Tri-X 400 as a result of this investigative effort, a result that was not planned.
The links below present more examples of individual film stocks. They don't include isolated grain-level (pixel-level) extracts like done above, but still, one might 'see' some of the grain results in many of the examples, maybe helping to differentiate specific films from others.
Ilford Films
Working with Ilford Delta 400
Working with Ilford FP4+ 125
Working with Ilford HP5+ 400
Ilford HP5+ vs Ilford Delta 400
Kodak Films
Working with Kodak TMax 400
Working with Kodak TMax 100
Working with Kodak Tri-X 400
So, what to say as a conclusion? I've spent several weeks looking at and for example images, and in the process of composing this post. I've recognized during this process that I look at the film grain of these images with the eyes of a digital photographer, returning to film in the 21st century with completely different eyes than maybe those who started with film in the past. I think too, I'm not alone in how I view and accept film grain. Each new film release, or updated formulation, seems to deliver a finer and finer grain structure, some now virtually grain-free.
In those final four examples, I see I approach exposing film in a way that seeks to minimize the resulting grain. This is done by reviewing the ideas of others and my own confirmation experiments. It's not that I don't want grain, rather, I don't want obnoxious grain, the type and level of grain that I seem to 'see' first, even before seeing the image.
From the people I seek advice from online, most everyone says to 'overexpose' your 35mm film. The minimum suggestion is a default +1/3 stop, whether you adjust the ISO speed or use exposure compensation. The idea is to give those silver halide crystals as much light as possible. Many sources suggest too to rate the ISO sensitively of various film stocks as different than the 'official' box speed. A film like Tri-X 400 I now load as ISO-250 and then just use neutral metering from the SLR camera. My EOS 1v automatically reads the canister DX code, so I just override the camera's 400 number from the DX code to 250 before starting to shoot.
Hopefully, you'll find this presentation interesting, if not actually helpful. As always, the images are scanned and then edited in Adobe Lightroom Classic, so the over-exposed results are even more different in the final edit than was captured from the camera. My personal B&W tastes seek a higher contrast, where I'm whitening the whites and darkening the darks in most every frame to achieve the results presented in these examples, beyond the effort to manage film grain.
I shoot 35mm, rather than larger formats. When I look at larger formats, especially B&W images, I tend to note the absence of film grain. Those larger format film types tend to use finer crystals, as more film surface is exposed to light as compared to a frame of 35mm film. I'm not trying for grain-free film photography, rather, just a result that minimizes the grain in the 35mm format I shoot.
Some photographers love the grainy look of film, because it adds texture, mood, and character to their images. Other photographers prefer a smooth look (less grain), because it enhances the clarity, detail, and realism in their images. I've come to appreciate the 'classic' graininess of Tri-X 400 as a result of this investigative effort, a result that was not planned.
The links below present more examples of individual film stocks. They don't include isolated grain-level (pixel-level) extracts like done above, but still, one might 'see' some of the grain results in many of the examples, maybe helping to differentiate specific films from others.
Ilford Films
Working with Ilford Delta 400
Working with Ilford FP4+ 125
Working with Ilford HP5+ 400
Ilford HP5+ vs Ilford Delta 400
Kodak Films
Working with Kodak TMax 400
Working with Kodak TMax 100
Working with Kodak Tri-X 400
Feb 16, 2024 05:29:35 #
tcthome
Loc: NJ
CHG_CANON wrote:
B CONCLUSION /B br br So, what to say as a conc... (show quote)
Same go for color film & is there a quality difference in the color filters used for B&W film or any recommendations? Thanks for any replies.
Feb 16, 2024 08:16:52 #
tcthome wrote:
Same go for color film & is there a quality difference in the color filters used for B&W film or any recommendations? Thanks for any replies.
Not sure I understand the question, sorry. If colored filters is being asked in the same vein as UV filters, I use B+W F-PROs, the same as older UV filters before their current XS-PRO line of filters. I don't think colored filters for B&W film has migrated to their newer filter model.
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