How to work with the narrow latitude of color reversal (slide) films
Exposure latitude is defined by the satisfactory range between the shadow and highlights at which details can still be visible and color reversal (slide) films are known to have exposure latitudes that are much narrower than black and white, or color negative films. Accurate metering is important when using films with narrow exposure latitude and graduated ND (GND) filter usage can be very helpful, especially when shooting landscapes.
That said, a GND may not always be enough.
You see, I brought an almost complete set of GND filters to use with my landscape photography and although I remember metering my scenes carefully, I found myself occasionally disappointed with my results. They were very inconsistent; both good and bad. In fact, I should say that I got few good and many bad images! Put simply, even with the GND filters in use, the skies were still being blown out or the foregrounds were just too dark to be useable.
I must admit that the main reasons for my failed shots were my own mistakes. I knew I couldn’t continue like this and that I must reconsider my method for taking these kids of photographs by learning to effectively use my equipment.
In this article, I will be sharing how results like this lead me to devise a (simple!) method to get better, more consistent results.
Here’s what I’ll be covering:
I use a Leica M7 which has an automatic aperture priority mode. However, for shooting landscapes with slide film, I use it in manual mode (by choosing the shutter speed and aperture manually). I use automatic exposure mode just for reading the exposure through the finder.
For exposure readings, we can use external light meters or a built-in camera meter. If using the built-in camera meter, it is important that it be readable in low light conditions. If the meter shows a number (speed display in the finder), I prefer bright led. If it’s not showing a number, an over or under light indicator is also great as we can read the exposure manually by changing the shutter speed.
For shooting landscapes with slide films, it is important for me to have a manual shutter with the slowest speed up to 1 sec and a bulb mode. Aside from 1 sec, I also need one stop increments: 1 sec, 1/2 sec, 1/4 sec, 1/8 sec, 1/15 sec, and so on. My cameras slowest manual speed is up to 4 sec. It is good, but we can always use bulb mode for longer than that.
I used a Leica Super-Elmar-M 21mm f/3.4 ASPH lens. The lens has a rectangular GND filter holder. There is an adapter ring on my lens for placing the filter holder in front of the lens.
For shooting landscapes, I always use GND filters to help block strong light from the sun and even-up exposure across the scene. These filters are important to bring the sky (highlights) and shadow exposure closer together so they are within the range of slide film’s narrow exposure latitude.
I use square or rectangular-type filters. They are quick to attach or detach from the lens with a simple slide-in holder. This is quite important to me as I may stack multiple filters and need to change the configuration easily, especially during sunset or sunrise where the light changes very fast. With these filters, I don’t encounter problems with vignetting when stacking filters or capturing long exposures.
Another important thing: I don’t want filters that introduce any color cast from the filter. They must be color neutral. For safety, I choose filters that are made from glass. Color cast from the film stock is something entirely different and I discussed it in more detail in my previous article.
The filter size I use is 100mm (4×4 inch system). Although the 100mm size is not quite suitable for my small lens, when you compare it to 3×3 inch or smaller systems, there are many more clagg filter options (as opposed to plastic).
With the 100mm system, my Graduated ND (GND) filter size is 100x150mm. I have several options, but now I mostly use two soft edge GND filters (3 and 5 stops). When needed, I can also stack these two filters for more highlight blocking.
My mistakes and solutions
One: how I used my filters
My lens has a filter diameter of 46mm. So the 100x150mm filters are much larger when compared to the small diameter of my lens. This means the large graduated filter won’t have as much of an effect as a smaller one. This is due to the filter’s effective blocking area being quite small (see below). Using such a large filter without considering the effective blocking area was mistake number one.
So I thought, why not check the “blocking result” of the filter on my lens directly? To do this, I slid my GND filter down until the effective blocking area (above) fully covered my lens. Then I pointed my camera to the sky and checked the exposure to see the actual blocking result.
That is how I read the highlight exposure.
This simple solution helped me get the accurate exposure I needed with the in-camera meter, because I metered based on the actual conditions:
- By pointing directly to the subject.
- With filter in place while reading the exposure.
I will come back to this with some examples a bit later.
Two: taking the shot with auto exposure mode
Using the camera’s aperture priority mode for taking my shot was mistake number two. Although I manually read both shadow and highlight exposure, and applied the correct GND filters to compensate, I just took the shot using my camera’s automatic mode.
I let my camera decide the shutter speed automatically and sometimes I liked the results, but sometimes not.
Even if the exposure was perfect (balanced shadow and highlight), it didn’t always generate an image that I liked, as in the following example
The photograph above shows balanced shadows and highlights – it should be perfect but actually, I could have had better control over the shadows and highlights. To do this, I needed to shoot manually, where I could choose the shutter speed myself.
Here is the result from a manual shutter speed selection.
Look at the difference in the sky and foreground. The sky is a bit under exposed with visible texture and I much prefer this compared to the previous result.
Third: not reviewing the overall scene
I just pointed the camera and read the exposure based on small particular areas. It may sound obvious but this is very important especially in low light conditions (during sunrise or sunset) and the where foreground is quite complex.
Even if the focal point of the photograph is on a certain object, I must still check the exposure meter reading from several different areas in the foreground and get the overall darkest part of the exposure.
For the sky (with GND filter applied), I must meter the brightest area and for shooting during the sunrise or sunset, I can point directly to the sun and read the exposure just to get the brightest exposure limit. This way, even the harsh light is under control.
I will explain in more detail with examples later but for now, here is an example with the sun captured while the foreground is still clearly visible.
The above image is just an example of the possibilities we have if we read the exposure carefully, based on the overall scene from the foreground and the sky. Of course, the resulting image is a matter of taste! As I will explain later, this is just one alternative you can make.
So, after realizing the three mistakes I was making, I changed how I worked. Here’s a quick recap:
- Understanding the relationship of the GND filters I was using to my specific lens – fine tuning.
- Ensuring I was in full control of my exposure.
- Ensuring that I had effectively metered the entire scene I wanted to capture.
Next I will summarize my steps for putting these realisations into practice.
My method explained
Step one: get the foreground (shadow) exposure
Since I use the camera’s built-in meter, I just point my camera to the dark area in the foreground and take note of the shutter speed. For example, I get: 1/30
Step two: get the sky (highlight) exposure
I put the GND filter in front of my camera and point it to the sky. My filter should be positioned like the example below, with the GND’s transition area fully covering my lens.
Then I check the exposure. If the shutter value is close enough to the shadow exposure (1/30) it means the GND filter I chose is correct.
Step three: take the shot
I put my camera on the tripod and position the GND filter normally (centered):
Then, I manually set the shutter speed to 1/30 and take the shot.
You might be interested in…
If the sky and shadow exposure still has a large difference, I just change the GND filter, or combine multiple GND filters if needed. That said, the sky and foreground exposures doesn’t have to be the same. If they are close enough, the resulting photograph should be fine.
Try to bring the highlight exposure closer to the shadow exposure with no more than 3-stops difference.
And here is the interesting thing: I can make a bracketing plan based on the difference. We can see how each shutter renders a unique image based on this “satisfactory range” that we set. Examples to follow.
Creating and using a simple but effective bracketing plan
Note that a 3 stop range is what I find works most effectively for my photographs. Your preferences may differ. Using this range gives me an acceptable balance between shadow and highlights and of course, with only 3 stops difference, I don’t need to bracket too many exposures.
I should also say that I find that it useful to take notes of the exposure reading for my shots. This is especially when I come to review my images and locate the possible cause of the problem if I got bad results.
Here is a simple table I use in my notebook:
And for reference, I also take note of the exposure reading without any filters, for example:
Now let’s see some examples.
Example 1: Sunset, Provia 100F
First, here is a shot without any filters:
I got a dark foreground and lost the colors in the sky. Looking at my notes of the exposure reading, this unfiltered exposure was taken using an aperture of F/11 here.
To create a bracketing plan for this scene, I first checked the foreground (shadow) exposure, which was 24 seconds. Then, since the sunlight was very strong, I used my two GND filters (3+5 stops) to check how they performed at blocking the highlights.
Pointing my camera to the sky, I found the brightest exposure: 3s. So my simply bracketing guide is:
With the filters applied, there were 3 stops separating the sky and shadow (3s – 6s – 12s – 24s). Perfectly workable against the 3-stops of exposure latitude I note above.
With these two figures, I created my bracketing plan. I didn’t need to shoot at 3 seconds, because that exposure was based on the brightest area in the sky (the sun). So, my bracketing plan would be:
24 sec to > 3sec. I chose: 24 sec, 12 sec and 8 sec. Here are the results:
Example 2: Sunrise, Agfa Precisa CT-100
First, here is the shot without any filters:
I used a 35mm lens here, so the framing is different with the others images.
Taking note of the exposure reading, the foreground gave me a 1/8 sec exposure. To bring the sky within three stops, I used two GND filters (3+5 stops) and pointed my camera directly to the sun. I got 1/45 sec.
I won’t shoot at this speed. I just need this as a reference (my max limit). Here’s my note:
There are only 2-stops of difference between 1/8 sec and 1/45 sec, so this is better than the previous example.
My bracketing plan the, would be from 1/8 sec to < 1/45 sec. On my manual shutter dial, under 1/45 is 1/30, 1/15, and so on. I decided to use 1/15.
Before I took the shots, I saw the foreground was still dark. I remember some failed shots I got during the same low light conditions, so I improvised and added a slower speed to my bracketing plan, that is 1/4 sec.
Here are the results:
You see, each shutter speed renders a unique image. More saturated sky colors can be seen at 1/15 sec. While clear foreground details can be seen at ¼ sec. However, from the results, I prefer 1/8.
But you may also like the 1/4 sec with foreground more clearly visible.
The sun was captured with its surrounding colors and even the foreground details are still visible. The scene was so beautiful, so I didn’t want to miss seeing how each shutter speed rendered the image.
Imagine if the sky has incredible color and you like it. Then you might choose the 1/15 sec exposure. These are the result based on the satisfactory range in our bracketing plan, with not more than 3-stops difference between the shadow and the brightest highlight exposure.
Here are sample photographs based on the method described above. To scan, I used the default settings on my Epson Perfection v600 scanner. No adjustments, except cropping some of the images.
When using slide films, I should bring the brighter highlight exposure closer to my shadow exposure with the help of the correct GND filter. For my preference, the maximum difference should be no more than 3-stops ) 2-stop difference is better!)
I set my shutter speed at the shadow exposure (shadow priority) and take the shot or make a bracketing plan based on the shadow-highlight exposure range.
Some quick takeaways for reading the exposure:
- When reading the sky (highlight) exposure, I apply my GND filter for reading the actual filter blocking result. I meter directly to the sun or brightest area on the sky, but only use it as a reference (max limit) for taking the shot. I won’t shoot at that speed. With this, I can control even the harsh light from the sun and make surrounding colors visible.
- When reading the foreground (shadow) exposure, I must measure the darker area and make sure that it is (overall), the darkest part of the exposure in the foreground. In difficult low light conditions, I can add a 1 stop slower exposure in my bracketing plan, just in case I’m not sure.
Bracketing based on the shadow-highlight exposure reading above can produce unique images that can be a matter of taste. I love how color reversal (slide) films render colors, and I don’t want to miss seeing how each shutter renders an image within this satisfactory range.
Final notes and summary
Reading the exposure with a filter applied like I do may not be needed if you’re certain about the actual reduction stops your filters have. In that case, simply read the sky’s brightest exposure point, subtract the filter factor, and done.
You got the highlight exposure for your bracketing plan.
We may have different equipment, but regardless of the filter size, lens diameter, the exposure meter we use, or characteristics of the filters, etc., we can see how our equipment perform by testing them directly with bracketing plan as explained above.
In short, an adjustment can still be made to obtain an image in that “satisfactory range.”
So before I sign off, let’s check the before and after results one more time:
Thanks for reading!
~ Yusuf Wiryonoputro
Read the full article here
Leave a Reply