14 mins read

The “Appropriate” Exposure of Film

Or why acquiring it proper in camera is not the be all and end all.
Michael Elliott — Fine Art Film Photographer-Flâneur and Londoner at Big
This was inspired by my answer to the following Quora query:

What is the distinction among a a single cease underexposed adverse and a two cease underexposed adverse when utilizing black-and-white film?

Film photography is a fascinating and rewarding hobby but it can also be difficult and frustrating at occasions. A single of the most widespread sources of confusion and anxiousness for film photographers is how to expose their film properly. As opposed to digital photography exactly where you can quickly verify your exposure on the LCD screen and adjust it accordingly film photography calls for a extra cautious and deliberate strategy. You have to rely on your light meter your expertise and your intuition to estimate the right exposure settings for your film and your scene. And even then you will not know for positive if you got it proper till you create and scan your film.
But what does it imply to expose film properly? And how do various forms of film react to various levels of exposure? And what if you make a error and overexpose or underexpose your film? Is there a way to repair it or even use it to your benefit? In this post we will attempt to answer these inquiries and extra by exploring the principles of exposing black and white colour adverse and colour slide film. We will also appear at how improvement of film can compensate for exposure errors and how you can use a mixture of overexposure or underexposure and compensated improvement to accomplish particular artistic effects.
Black and White Film
Black and white film is the simplest and most versatile kind of film when it comes to exposure. It consists of a single layer of silver halide crystals that are sensitive to light. When the film is exposed to light some of the crystals are converted into metallic silver forming a latent image that is later created into a visible image. The extra light that reaches the film the extra silver is formed and the darker the image becomes. Conversely the much less light that reaches the film the much less silver is formed and the lighter the image becomes.

An instance of pushing Rollei Paul and Reinhold (ISO 640) to 1600 (roughly 1 2/3 stops). Even though shadow detail is minimal there are nonetheless shadows that can be pulled out of the image. Photo credit: Michael Elliott
Black and white film has a wide exposure latitude which suggests that it can tolerate some degree of overexposure or underexposure without having losing as well a great deal detail or tonality. In truth a massive quantity of photographers deliberately overexpose or underexpose their black and white film to accomplish specific effects. For instance overexposing black and white film can outcome in a low-contrast image with soft tones and smooth transitions. Underexposing black and white film can outcome in a higher-contrast image with harsh tones and sharp edges.

Fuji Neopan 400 pushed to 1600. Shadow detail is pretty much non-existent. Even even though this was in broad daylight I had an orange filter and polariser on and to accomplish the needed depth of field with a affordable shutter speed I had to use a larger EI than the box speed. Photo credit: Michael Elliott
On the other hand overexposing or underexposing black and white film is not adequate to accomplish these effects. You also will need to adjust the improvement time accordingly. This is exactly where the notion of compensated improvement comes in. Compensated improvement is a strategy that entails altering the improvement time primarily based on the exposure level of the film. The basic rule is: overdevelop underexposed film and underdevelop overexposed film. This way you can balance out the exposure errors and bring back some detail and tonality to your image.
For instance if you underexpose your black and white film by a single cease (i.e. half the quantity of light required for a right exposure) you can compensate by rising the improvement time by 20%. This will improve the density of your adverse and make it darker bringing out some shadow detail that would otherwise be lost. If you overexpose your black and white film by a single cease (i.e. double the quantity of light required for a right exposure) you can compensate by decreasing the improvement time by 20%. This will reduce the density of your adverse and make it lighter preserving some highlight detail that would otherwise be blown out.

Regardless of my very best efforts the shadows are muddy and not detailed in this shot taken on Fuji Neopan 400 at 1600 and pushed 2 stops in improvement. Pushing does not constantly operate wonders for a offered scene. Photo credit: Michael Elliott
Of course these are just rough recommendations and various films may perhaps call for various amounts of compensation. You may perhaps also want to experiment with various degrees of compensation to accomplish various outcomes. For instance some photographers choose to overexpose their black and white film by two stops or extra and underdevelop it by 50% or extra. This produces a incredibly low-contrast image with pretty much no shadows or highlights developing a dreamy or ethereal impact.
Colour Negative Film
Colour adverse film is extra complicated than black and white film when it comes to exposure. It consists of 3 layers of emulsion each and every sensitive to a various colour of light (blue green and red). Each and every layer also consists of chemical compounds referred to as dye couplers that react with the developer to type dyes that correspond to the opposite colour (yellow magenta and cyan). When colour adverse film is exposed to light some of the silver halide crystals in each and every layer are converted into metallic silver forming a latent image that is later created into a visible image. The extra light that reaches each and every layer the extra silver is formed and the extra dye is made. The outcome is a adverse image with an orange hue that requirements to be inverted and colour-corrected to make a optimistic image.
Colour adverse film also has a wide exposure latitude but not as wide as black and white film. It can tolerate some degree of overexposure or underexposure but not without having affecting the colour balance and saturation of the image. In basic colour adverse film handles overexposure far better than underexposure. Overexposing colour adverse film can outcome in a extra saturated and vibrant image with extra detail in the shadows. Underexposing colour adverse film can outcome in a extra muted and dull image with much less detail in the highlights.

An instance of pushing colour film gone right — this is Fuji CDU-2 a colour optimistic duplicating film with a incredibly low native ISO of 6. On the other hand by cross processing in C41 and pushing 2 stops I was in a position to eke out an EI of 200. The grain is pretty noticeable and the colour shifts had been challenging to right for but it was attainable. Detail all through is excellent. Photo credit: Michael Elliott
On the other hand overexposing colour adverse film as well a great deal can also have some drawbacks. It can improve the grain and noise of the image as nicely as introduce colour shifts and casts. For instance overexposing Kodak Portra 400 by extra than 3 stops can make the image appear extra yellow and green even though overexposing Fujifilm Superia 400 by extra than 3 stops can make the image appear extra red and magenta. These colour shifts can be corrected to some extent in the course of scanning or printing but they may perhaps also have an effect on the all round mood and tone of the image.
On the other hand some photographers deliberately overexpose their colour adverse film to accomplish a specific appear. For instance overexposing Kodak Portra 400 by a single or two stops can make beautiful pastel tones with smooth transitions and low contrast. This is specially appropriate for portrait photography as it can build a flattering and soft skin tone. Overexposing Fujifilm Superia 400 by a single or two stops can make vivid and punchy colours with higher contrast. This is specially appropriate for landscape photography as it can build a dramatic and lively scene.
As opposed to black and white film colour adverse film does not advantage a great deal from compensated improvement. Altering the improvement time of colour adverse film can have an effect on the colour balance and saturation of the image but not in a predictable or constant way. Consequently it is very best to create colour adverse film according to the regular method (C-41) and adjust the exposure level in the course of shooting or scanning.
Colour Slide Film
Colour slide film is the most challenging and demanding kind of film when it comes to exposure. It consists of 3 layers of emulsion each and every sensitive to a various colour of light (blue green and red). Each and every layer also consists of chemical compounds referred to as dye couplers that react with the developer to type dyes that correspond to the identical colour (blue green and red). When colour slide film is exposed to light some of the silver halide crystals in each and every layer are converted into metallic silver forming a latent image that is later created into a visible image. The extra light that reaches each and every layer the extra silver is formed and the much less dye is made. The outcome is a optimistic image on a transparent base that can be viewed straight or projected onto a screen.

Taken on Fujichrome MS100/1000 — a film deliberately formulated for push-processing this was shot at EI200 and processed for 8m30s in the initially developer for a 1 cease push. Although it is not ideal and I would not attempt to push this film to EI 1000 (specially given that it is extended discontinued and the examples I identified had expiration dates in the early 2000s) it is got a excellent colour balance and shadow detail is not absolutely absent. Photo credit: Michael Elliott
Colour slide film has a incredibly narrow exposure latitude which suggests that it can tolerate incredibly small degree of overexposure or underexposure without having losing detail or tonality. In basic colour slide film handles underexposure far better than overexposure. Underexposing colour slide film can outcome in a darker and extra contrasty image with extra saturated colours. Overexposing colour slide film can outcome in a lighter and extra washed-out image with much less saturated colours.
On the other hand underexposing or overexposing colour slide film as well a great deal can also have some drawbacks. It can decrease the dynamic variety and detail of the image as nicely as introduce colour shifts and casts. For instance underexposing Kodak Ektachrome 100 by extra than a single cease can make the image appear extra blue and cyan even though overexposing Fujifilm Velvia 50 by extra than a single cease can make the image appear extra yellow and orange. These colour shifts can be challenging or not possible to right in the course of scanning or printing as they are inherent to the film itself.
As opposed to black and white film but like colour adverse film colour slide film does not advantage from compensated improvement either. Altering the improvement time of colour slide film can have an effect on the density and contrast of the image but not in a predictable or constant way. Consequently it is very best to create colour slide film according to the regular method (E-6) and adjust the exposure level in the course of shooting. There had been particular films that had been engineered to let for some type of push processing compensation (Fujichrome MS100/1000) but these had been uncommon and now discontinued. Other films like Fujichrome Provia 400X (now discontinued) and 100F lend themselves far better to an up-to-2-cease push but it is a great deal far better to shoot these at their box speeds.
Conclusion 
A s you can see exposing film properly is not a very simple or simple job. It depends on several elements such as the kind of film the lighting situations the topic matter and the artistic vision. On the other hand it is also not anything that you will need to obsess more than or be concerned about as well a great deal. Film photography is not about acquiring it proper in camera all the time. It is about experimenting with various approaches and effects understanding from your blunders and successes and enjoying the method and the outcomes.
In this post I have covered some of the standard principles of exposing black and white colour adverse and colour slide film. We have also looked at how improvement of film can compensate for exposure errors and how you can use a mixture of overexposure or underexposure and compensated improvement to accomplish particular artistic effects. I hope that this post has offered you some valuable details and inspiration for your subsequent film photography project.