ISO Settings & Digital Photography

by William Lulow

We should remember that today’s cameras and lenses are quite capable of doing the jobs we ask of them and quite possibly are better than those made for film. Lately, I have been experimenting with higher ISO numbers. When you use ISO settings like 1000 or even 4000, you are allowing the camera’s sensor to “see” images with a lot less light than normal. In the days of film, when we were shooting in low light conditions like at concerts or venues with very little light, we would UNDEREXPOSE the film and then push-process it in developers that would enhance the grain of the film to obtain usable images. 

Today’s digital sensors are way more sensitive to light than any film ever was. I have made many concert images of performers at night clubs and other places where I had to bump up my ISO (sensitivity) settings in order to be able to record any kind of decent image. Don’t forget that I am still looking for overall sharpness or what they sometimes refer to as “sharpness in grain.” The downside to doing this is that the images, in the case of film, would show a bit more grain than normal. In the case of digital images, the trade off is that the pictures are also grainier, but we now refer to that as “noise.” But depending on the kind of photos you want to make and their intended uses, sometimes more grain or noise is acceptable in order to be able to make the images you want. 

One other thing to keep in mind is that when you use higher ISO numbers, you allow shooting at smaller apertures which tend to enhance the sharpness of any image. First, they increase the image’s depth-of-field making the entire photo sharper. Second, they permit shooting at faster shutter speeds which tends to reduce blur in an image. Both results are positive effects of using the increase in sensitivity.

I have been photographing musicians for a long time, as a matter of fact, ever since I began thinking of photography as a career. Here is one early attempt shooting a concert with just stage light:

This image of Judy Collins in concert, was one of the first concerts I photographed. I was using a Nikon F camera with a 200mm f/4 lens and TRI-X film rated at ASA (ISO) 400. The venue was probably using mercury-vapor lights for the stage and I was also most likely using the lens wide open. The film was rated as if it were ASA 1600 and push processed in a developer called ACUFINE which treated the film’s emulsion as if it were more sensitive than it was. So you can see the grain in the print, but the image is still sharp overall. It’s a level of grain or in digital language, “noise” that would be considered acceptable if the image was used in a newspaper, for instance (which it was). 

I also have made other images from regular 35mm Tri-X film and enlarged them to relatively big sizes. This one of Jerry Garcia was made into a 32×44″ print:

It’s still pretty sharp although the grain is definitely noticeable. 

When I am shooting with my digital cameras, I sometimes rate the ISO (sensitivity) at 2500 or even up to 4000 and the images are still acceptable. When you use a higher ISO number it allows you to use a smaller aperture (f/stop) as well as a faster shutter speed, which as I mentioned, yields sharper images. Here is an image I just made a few years ago:

This image was made with my Canon 90D (32MP sensor), ISO 2500, f/5.6 @1/100th of a second, so there was some movement of the hand captured. When shooting in low light situations with musicians, not only do you need more depth-of-field using smaller apertures, you also need a higher shutter speed to stop any motion. My usual exposures for this kind of shot are ISO 2000-2500, f/4 or f/5.6 (sometimes I can even shoot at f/7.1). All of this adds to the overall image sharpness as well. Another factor is that noise or digital grain, isn’t the same with digital cameras as grain was with film. The effect is much softer and therefore much less noticeable. 

So, the takeaway from this article is that higher ISO settings can be useful if you learn how to use them correctly and you know the kinds of pictures you are looking for. Another example:

Here, the motion of the strumming hand was stopped with the 1/160th of second exposure and everything else is rendered fairly sharp as well. This was made at ISO 2000, f/4 @ 1/125th of a second. It was converted to monochrome. 

Besides my concert photography, I have begun using the higher ISO settings whenever I needed more light in general. I made several images of my granddaughter in swimming competitions:

This image was made with my Canon 135mm f/2 lens and ISO setting of 4000, f/5.6 @ 1/1000th of a second. I was truly amazed at the overall quality of the image. Even the water drops are fairly sharp. Moreover, the quality of the image is satisfactory for almost any use. 

Keep in mind that these kinds of sensitivity settings are for very specialized conditions where you need to use smaller apertures and faster shutter speeds and when you know that the end use of the photographs will allow for some grain. When I can control the light as in my studio, I always use ISO settings of 100, maybe 200 maximum, to render my product shots or portraits/headshots as clear as possible. That’s the desired result always.