Pentax used to be among the trusted and respected camera manufacturers when film was the medium people were using in photography. Since the digital revolution, Pentax has seemed to disappear. The reality is, they haven’t. They’re still pushing the limits, especially with regards to ISO, and offering fantastic cameras. The problem is a lack of marketing and an ever shrinking audience that cares.
While it’s impressive that the new Pentax KP digital SLR can shoot at an enormous ISO, there are plenty of established blogs and news sources already discussing the features this camera has to offer. Rather, I’d like to take some time to talk about why a DSLR that can shoot at 819,200 ISO matters. The understanding of what ISO is will matter before the importance of this feat will make sense as well as a basic understanding of how ISO works.
What is ISO?
Film has a direct influence on ISO as the ISO rating is the digital equivalent to film speed. Some of you younger readers are probably scratching your head about film speed too. That’s OK, it’s easy to grasp. Both film speed and ISO use a number scale to determine the film or camera’s sensitivity to light. With film, you buy film with speeds of 100, 200, 400, or 800. The higher the film speed, the less light is needed to capture an exposure. ISO works the same way, using the same number scale. The difference is that ISO is adjustable and not a permanent rating to the camera. Also, because it’s adjustable, it can be set to ISO speeds in between the standard ones. For instance, ISO 160 can be used instead of choosing between 100 or 200.
The drawback to higher film speeds or higher ISOs is more grain or noise in the photo. As film speed increases, the amount of film grain that is visible also increases. The same is true for ISO, only its referred to as noise. Film grain and noise don’t look the same, though. Film grain is usually more uniform in patter and appears more like static. Noise can vary in pattern, color, and even look as splotches of the section of image under it. Noise is far uglier than grain, but it has been around since digital cameras first came to be and we’re getting used to seeing it. Camera manufacturers are also getting better at reducing it and software is getting better at cleaning it up.
Why is ISO 819,200 Important?
First thing is first — just because a camera can shoot at ISO anything doesn’t mean it will look good. My Canon 7D Mark II has a maximum ISO of 25,600 ISO but shooting above 6400 is unattractive and even between 3200 and 6400 begins to lose its appeal in many situations. Anyone that has experience with ISO might see 819,200 and wonder what the point is, especially if photos get noisy as such comparatively low ISOs.
There are a few points and one of the biggest is about pushing the limits. If we stay stagnant in technology, what we have may get refined but may not expand. Pushing such high ISO levels in return pushes other industries and software to figure out how to make those levels usable. I’m not saying the Pentax KP will produce ugly photos at ISO 819,200 because I haven’t seen samples or played with the camera. It’s entirely possible that Pentax or Sony (the manufacturer or the image sensor Pentax is using) have figured out how to reduce noise effectively at that high of an ISO. However, from experience, I’m not expecting a very clean image that high.
Pushing ISO 819,200 means more flexibility to the photographer with regards to getting the shot or missing it in difficult to impossible lighting conditions. Many would argue that a noisy image is better than no image at all, especially if what is being captured is important. What if a political movement occurs in near blackout conditions? It’s not likely, but it could happen. High ISO settings would be needed to capture the action.
A real world example of using high ISOs artistically is with regards to setting up the shot. Night photography can be very beautiful and it’s a subject I plan to explore more in the near future (I live in too urban of an area for this), but 2 problems exist. It is often too dark to see how the photo is framed or composed which also means it’s just as difficult to determine focus and night photography usually requires long exposures. Imagine taking a 30 second exposure to find out it’s not in focus. Using a higher ISO means less exposure time and it can also mean seeing your shot easier to set it up properly the first time. Due to the high noise at a high ISO, you may still take the photo with a lower ISO with a long exposure, using the high ISO option to help set up the shot.