One of the great decisions in camera purchase today is that of digital or film. Each has its own
and has a different market. Disclaimer - I have a film
- Film vs Memory
- Film is cheap. Memory is not. Granted, memory is a one-time investment, however, it is a very expensive one that may cost more than the camera itself for a reasonable capacity of high quality photographs. Most digital cameras use some form of memory to store the pictures on. There are a few high end cameras that are actually part CD-burner and burn the images directly to the CD rather than storing them in memory. There are also some cameras that store the images to a floppy disk of some sort. Please note that cameras that store to floppy disk often have very poor image quality or go through floppy disks as if they were candy.
Cameras that store images in memory often have a number of formats that they can store them in from high quality to low quality. Most cameras can do 640x480 (and thus it is a reasonable benchmark) and get about 5 pictures/megabyte at this resolution. An 8 megabyte stick is about the same as a roll of 36 exposure film in capacity. However, at high resolution (2160 x 1440), this takes 10 times more memory than the 640x480 requiring almost 2 megabytes/picture. To get the equivalent of a single role of film a 64MB memory card will be necessary. Each 64MB costs over $100 and 8MB cards costs in the $40 range.
It is true that memory cards are reusable, however the key question is how many high resolution pictures are feasible to carry around? With film, it is easy (and not expensive) to carry around 10 or so rolls of film. To carry the same amount of digital camera memory around costs between $400 and $1200. This is a sizeable investment.
You may ask "why carry that much film around?" The answer is quite simple. Often when going out and taking photographs, it is not difficult to use up a few rolls of film that you were planning to take. Then, when driving back, suddenly you come across the best sunset ever and reach back to grab another roll of film. It would be terribly unfortunate to run out of film or memory at this point.
There are ways to increase the amount of memory carried by purchasing a hard drive and memory card reader. These readers simply store the information on the card to the hard drive. A gigabyte can store on the order of 1,000 high resolution photographs.
- Pre film/CCD lens
- Only the highest quality (example: Cannon EOS D30 @ $2850) digital cameras have the ability to change the lens it comes with. Most of the time all that is required is a simple zoom lens that most every digital camera comes with. Some of the mid-high end cameras even have threads on the lens so that various filters may be applied.
While there is Photoshop for anyone with a digital image to modify the image, there are some things that have to be done before the lens to get proper effects. Most notably is the polarizer that changes how water reflects, reflections in glass, and the sky/cloud/ground contrast. These things must be done before the light hits the film or CCD.
There are also times when it is necessary to change the focal length of the camera. This is especially the case if you wish to photograph things that are very close to the lens. Often this type of photograph is of flowers, small (stationary) animals, and textures.
- Shutter speed, aperture, and film advance
- It is true that the higher end digital cameras have the ability to change some aspects of the aperture or shutter speed, there are times when it isn't enough. The high end (that Cannon EOS D30 again) have shutter speeds between 8 seconds and 1/1000th of a second. Most digital cameras do not have even that amount of flexibility. This is often enough for all but the long exposure pictures. Night pictures of car lights are recommended to have an exposure of 30 seconds or more. Pictures of star trails and comets often are exposed for hours.
The ability to change aperture allows for the change of depth of field. With the smallest aperture everything is in focus - wonderful for landscape photographs. With larger apertures, only the target itself is in focus. The second technique is often used for photographs of people where nothing other than the face is to be in focus.
Admittedly, my camera does not allow me to control the advance of film - some day I would like a better camera body. Ever see a double exposure, where you sit there and wonder how it was done. Well, actually you know how it was done - the film was exposed twice. While this is doable in Photoshop, the most authentic way is with the camera itself. This type of photograph is simply not doable with a digital camera.
- Image quality
- At the time of this writing, the highest quality digital cameras are on the order of 3.25 mega pixels (2160 x 1440). This sounds like a lot, and it is certainly a high resolution image. However, the store I go to for developing photographs gives a free photo CD with it for photo club members. Yes, they do charge more than the drug store for the roll of film, but they have never messed up my negatives and give me good quality prints. From the photo CD, it is easy to extract a 1536x1023 image which has half as many pixels. With a reasonable quality slide scanner images on the order of 5 mega pixels can be retrieved from 35mm film.
35mm is near the low end of film size. For someone who is truly concerned with image quality the only alternative is a medium or large format film camera. The difference in quality is beyond comparison. This is especially the case when it comes to enlargements.
The information about how many mega pixels a camera can do is all well and good for nice high quality wallpaper or screen savers. However, may times we want something to hold in our hands - an image to take with us and put in a frame. In these cases, few printers come close to the quality of a photograph, and those that do, cost on the order of $1/picture (5"x7") to several dollars for a full page.
Film also has the added advantage of being able to be sensitized to different frequencies of light easily without changing the camera itself. There are several brands of film that have a higher sensitivity to the infrared end of the spectrum. Similarly, film has different speeds. A 100 speed film is wonderful for a bright sunny out door picture where you want the shutter to be open for as long as you can (see photographing flowing water) or hours of night exposure. A very fast film (1600 or higher) can be used to take photographs lit only by a candle in a dark room. With a large format film and a 16 film speed (yes, 16 - incredibly slow) it is possible to enlarge the image to the size of a wall with no loss of image quality.
- Conclusion
- Digital cameras are nice cameras and have their place. They are easy to take around and often provide a nice compact system for recording images. However, when something more than a snapshot is required they start to fail when compared to a good print camera unless one goes for the very high end of digital cameras. When even more artistic control or higher quality is required it gets very expensive to have an equivalent digital camera, if the digital camera can do it at all.
With snapshots, if a person is considering taking more than 40 pictures before unloading the memory the price of memory begins to get oppressive compared to the equivalent in film.