Author: David Huffman
If you’re an involved photographer, you probably debate with your friends (or in your own head) your choices of equipment on several levels. In many situations, size is a major consideration, here’s why…Size matters for image quality, equipment cost and equipment weight.
Image quality is my primary consideration in most of my photography. If I’m going to invest the time to take a photograph and additional time in post processing to perfect it, then quality is my major concern. I’ll admit that I’m obsessed with image quality and always have been. In digital imaging cameras today, cameras use sensors of different physical size as the first consideration in design of the camera. The illustration below shows that there is a wide range of image sensor sizes. The pinnacle for most amateurs is called “full frame” which is a reference to the 35 mm camera format of a film frame 24mm by 36mm, roughly 1 inch by 1-1/2 inches in size. The total area of a sensor affects the ability of the sensor to gather light and hold detail. Larger sensors gather more light, very useful in low-light and night photography and when using higher ISO settings. This is true even with high or low megapixel sensors. In cameras made in the last 5 years, most cameras have at least 12 megapixels, more than sufficient for high quality images, but the larger sensor cameras will always take a higher quality image when compared to a camera with the same megapixels but a small area. You’ll notice this difference in enlargements and prints over 8×10 inches and in cropped images, also in pictures using high ISO settings at ISO 800 and higher. All of the image quality characteristics are subject to your individual perceptions of quality, so you’ll have to decide what is “good enough quality” for you. I demand the most from my equipment and processes and make prints often over 30 by 40 inches for sale, so image quality, sharpness and smooth tone gradation with low/no noise and grain are very important to me. Other factors including lens quality and technique are also major for image quality, all else being equal.
If this is the case, then you might ask, “why use small sensors?” This brings us to the second and third size considerations. Small sensor cameras are (almost always) smaller and lighter in size for the camera body and for the lenses. Most “compact” cameras with a permanently attached lens use a smaller sensor to keep the entire device small and portable, even pocket-sized. Most manufacturers today make digital single lens reflex cameras in two formats, or perhaps even three. The full frame Nikon cameras are referred to as “FX” and the next smaller size format is called “DX”, and these cameras have approximately 30% less sensor area. FX cameras require larger lenses to cover the full frame, and DX cameras can use smaller lenses.
Smaller format cameras with smaller camera bodies and lenses cost less to manufacture and weigh less. Total system cost and weight can be very important factors in your photography. I travel on photography adventures many times each year and carrying two bodies with 4 or 5 lenses, flash and other accessories weighs from 20 to 30 pounds fully packed, and this is a consideration for airline baggage and for daily trekking in the field. The cost of equipment systems varies a lot by manufacturer, so it is difficult to be specific, but I’ll estimate here that a full frame system with one body and three lenses probably costs 50% more than the next smaller size system. (Keep in mind, too, that if you’re using full frame for maximum quality, you’ll also invest in the best lenses of each zoom or focal length range, increasing cost and size.)
I’ve included side by side images of DSLRs to illustrate the differences in physical size. The best way to make these decisions is to try them for yourself in a real photography retailer. On line you can see the measurements and weights for comparison, but you’ll appreciate the differences if you hold them in your hands.
Left to right: Nikon D3200 (DX format), Nikon D810 (FX format) and Nikon F5 (full frame film camera, one of the last and the best film SLRs in my opinion)
Also the differences in lenses are significant, left Nikon 18-55mm for DX format, right Nikon 24-120mm for FX format.
David is a Photographer, Instructor, Author and Trip Leader with Arizona Highways Photo Workshops. His books on Photography Instruction are available for Apple iPad, Mac and Amazon Kindle. Visit him at www.HuffmanPhotoArt.com.