Film & Sensor Sizes

The naming scheme for digital camera sensors is derived from old television camera sizes expressed as the diameter of the tube through which light enters to strike the sensor at the end of the tube. The sensor’s diagonal measurement is about one third less than that of the tv camera tube so camera sensor diagonal measurements are smaller than you might expect from their names.
Camera with a Four Thirds Sensor: Micro Four Thirds cameras are mirrorless.
Here are a few film and sensor dimensions, and their relative sizes compared to 35mm film and full frame digital sensors.
Type Format Dimensions (mm) Surface Ratio to 35mm
Width Height mm²
film 4×5 121 97 11737 1358%
film 645 56 42 2352 272%
Sensor 645 43.8 32.8 1436.6 166%
Sensor Full Frame 36 24 864 100%
Sensor APS-C 22.3 14.9 332.27 38%
Sensor four thirds sensor 17.3 13 224.9 26%
Sensor 2/3″ 8.8 6.6 58.08 7%
Sensor 1/1.6″ 8 6 48 6%
Sensor 1/1.8″ 7.2 5.3 38.16 4%
Sensor 1/2.7″ 5.3 4 21.2 2%


Nothing’s Changed?–Digital/Film Analogues

As I said in an earlier post, several years ago I resumed shooting and printing a lot. With some review at the Worcester Craft Center I went back out with my cameras and into the darkroom with less pain and more joy than ever. I changed formats from 35mm to 645 medium format when I bought a used Bronica ETRS.

There are parallels in digital photography. Point and shoots in general make nice images fairly automatically; that’s a big selling point for them. However, trying to edit nice looking images for fine art prints is not always successful.

second-growth-P3060086A combination of factors may account for this. if we say a pixel on a camera sensor and a grain of silver on a negative are equivalent, 20MP or more is approximately equivalent to the resolution of a 35mm film negative. The size of a small camera sensor in a low price camera might be 1/2.5″ or smaller; that is about 2 percent as big as a 35mm negative. The electronic noise that leaks from all those pixels on a small surface area can be thought to be equivalent to grainy film.

Film as a rule records a wider dynamic range of tones than a camera sensor. More contrasty imagery with detail and texture in both shadow and bright zones was possible in a single click of the shutter with film. Electronic noise has been suppressed or reduced in successive generations of digital cameras; and dynamic range has improved–greatly improved in HDR captures which combine multiple exposures for dark and bright regions in the frame.

Another consideration is the file format in which a digital camera saves its image capture. Many point and shoot and fixed lens cameras save in a lossy compressed format called JPEG. In simplified terms, the file is saved in a smaller space by first applying all the optional and automatic camera settings, and then tossing out other data that the sensor recorded but is not required for the picture. It’s like we made a print, and threw out the negative. We can still make some editing choices, but not as many.

The situation may be remedied in the digital world with the right choices. Get a larger format camera. Cameras have been manufactured to utilize many sizes and formats of film from 8mm x 10.5mm frames on disc camera film to 8″ x 10″ large format cameras and even bigger ultra-large formats. In the digital market, point and shoot and fixed lens camera sensor sizes range from say 2 percent to 100 percent the size of one frame on a roll of 35mm film. Their prices range around $80 to $2700 roughly in parallel with sensor size. Lower priced, higher sales volume cameras benefit from economies of scale; higher priced, lower sales volume cameras benefit from better build quality, more durable components, and superior optics.

We get the equivalent to a film negative in cameras that are capable of saving images in camera raw format. Everything the camera sensor recorded gets saved in raw. Some fixed lens cameras have this feature, but many only save in a compressed format such as JPEG. I’ll work up a selected list of camera sensor sizes and post it next time; and another list of selected fixed lens cameras that feature raw capability after that.

Metal Prints

My friend, Tom Wyatt, has exhibited some lovely color photographs of reflections on various kinds of natural and human made surfaces. His metal prints of these subject materials are amazing to see, if you get the chance.

I recently received a Groupon deal by email for $5 metal prints that includes a limited time offer to share it for additional savings. If you’d like to take advantage, you can find the offer here.

Here is one of the images I uploaded for printing:


Here’s another uploaded image, an unusual effort for me, solarized color infrared:


Because I have no experiences with the seller, I can’t personally endorse them; but I have had positive experiences with other Groupon deals in the past. Be sure to let me know, if you take advantage, what you think when you see your prints; now that I’ve got some metal prints in the pipeline I will do the same once they arrive.

Prehistoric Photography

When I was a kid, somewhere in high school, I probably thought sixty-somethings were from prehistoric times; I also bought my first serious camera, a Mamiya-Sekor DTL 2000(?) 35mm SLR (Mamiya only makes medium format nowadays)–on lay-away from Denholm & McKay. Before recorded history cities mostly had local department stores; and Macy’s was in New York–you had to go there to go to Macy’s. My best friend got a Nikkormat. That was Nikon’s economy brand–a solid, quality SLR none the less. I usually tell people I have been a photographer since about 1973, the year I began learning to work in the darkroom, but that’s just a convenient time to label as my beginning.

It was a step up from a long growing interest. I enrolled in a continuing ed course in black & white photography at the Worcester Art Museum ( for two semesters. Dennis Wixted was a patient, encouraging, and thorough teacher who, in addition to technique, taught photography’s history and the contempory scene. At his wake I was just one of many who shared their appreciation of his teaching and friendship with members of his family. I labored with the camera to do assignments and take personal shots, thinking about the camera settings, the light, the film… I think I thought more than I shot. It was a job for me to expose all the frames on a roll of film. Eventually, I started buying 24 exposure rolls of 35mm film, 36 exposures being the other common packaging, a little less challenging to finish.

BRONICA ETRSFor most of my later film photography before I changed to primarily digital cameras I used a Bronica ETRS. Here’s one of my images from that camera. The maple trees in the background were at the height of their blazing orange autumn foliage. I used an orange filter on the front of my lens to brighten the leaves that were in full sun to nearly white in my print.


Next time I go over to the dark side and start using digital cameras. Eveything is the same if you think about it.

Fingers and Digits

As I wrote last time digital photography was on its way to surpassing the market share of film or analog photography when I got much more active in the first decade of this century. In my mind, at first, it was hard for me to understand digital black & white photography. Plus, there is an aesthetic to each as practice: one a craft working in all physical media, the other seemingly technological, electronic, office-work-like. One emerges gradually before the eyes, the other instantaneously from the camera, or with a change of settings or a few clicks of the mouse. This thinking took a few years to work out in my mind.

What finally made me happy with digital photography is a realization that the same full spectrum light arrives at the surface of the negative or the surface of the camera sensor. There are parallel choices in editing software to choosing contrast filters and the like. I can still choose my preference of texture and brightness and gloss in photo papers. I can make alterations by hand, hand cut window mattes, and assemble frames.

Alternative chemistry equivalent with digital gear and editing.
Alternative chemistry equivalent with digital gear and editing.

What is different, do I think? One thing is an historical fluke. Right now serviceable good quality film cameras capable of producing very high resolution “captures” (up to gigapixels in large format) are available at a fraction of the up front cost for their digital equivalents. Afterwards, film and processing costs accumulate, making analog a non-competitive choice in commercial settings where expenses must be controlled. For us ordinary Joes and Josephines, film can be very satisfying at least occasionally or for certain uses such as landscape and architectural subjects. A good thing about today, is the variety of choices a camera enthusiast gets. I can shoot film and print in the darkroom, scan and print from my computer, scan or use my digital capture to produce a transparency for alternative printing processes, such as cyanotype, platinum and many others. A variety of chemistries, tools, and materials can be had from websites such as Jumping into these processes is easier than before digital emerged.

Toned Silver Gelatin Print
Toned Silver Gelatin Print

Another is the physical work (or play) in analog photography. It’s just fun to choose and use various films, papers, developers in different dilutions, amounts of agitation, and more in the darkroom to alter the impact of processing on the negative or photo paper; and then to watch the result gradually darken in as it sits in a trayful of developer under a safe light.

Who am I? Why am I here?

stspyridonsepiaI’m here because I have been a photography enthusiast for many years and my story includes years of shooting film and making a transition to digital cameras. Never a commercial photographer, I’ve mostly made pictures for my own pleasure and to fulfill the urge to create. Other than for social occasions like cookouts and holiday gatherings, I always shot black & white film; and mostly developed, printed, mounted, matted, and framed my own work.

I live in central Massachusetts, a place full of urban and suburban, rural, and (man-made) wild environments such as watersheds surrounding the Quabbin and Wachusett Reservoirs, and the Ware River any of which provide many subjects for the photographer.

In the early 2000s my passion for the camera greatly heated up. My mother was growing more frail. I joined the Worcester Craft Center and took some knife making classes as something completely different from the rest of my life to do for relaxation. Randi Laak, the instructor in the photo studio down the hall, once he learned I was a photographer invited me to take a class sometime. I did repeatedly for several years, taking advantage of the darkroom and the convenient time the courses were offered.

Computer-made Van Dyke Brown-like image
Computer-made Van Dyke Brown-like image

Film and digital shared the market when I began these classes, but digital was on its way to dominance. Digital hardware and software give me a great amount of power and flexibility for creating black & white, infrared, and color photographic images, although a much less hand crafted product in most cases. Next time, I’ll talk about my anxiety over that and how I wrapped my head around digital (but without completely abandoning analog) photography.