This method consists of using a regular flat-bed scanner with the lid open, and a dimming light source. In my case i used a work lamp and an inline dimmer switch. Place the negative on the scanner, emulsion side up. Place about 2 to 3 pieces of white paper for desired brightness, matching the number of pages to the intensity of your light source. You can also use a piece of opaque/ground glass which is a much better option, (you can see the grain of the paper sometimes, depending on the scene/negative). Then you need something to keep the negative flat. Glass, CD cases with weight on top etc. Then, simply adjust the scanner setting in the computer and play with it till you achieve a desirable result. Below are two examples of 120 film scanned using this method. With my cheap HP scanner and printer all in one set to 2400dpi, backed with regular notebook paper.
Using your digital camera: Build some sort of light box where you can light up the back of the negative indirectly and evenly. I used a photo box that was made for video- taping still images via a camcorder from the early 90′s. Behind the negative, once again, use paper or opaque glass. Using a Macro lens, tripod, and digital camera, set your camera to b&w and using Manual Exposure mode find the right exposure. Giving it an extra punch on the contrast control is also a good idea. You’ll have to play around with it a little bit, and if you have Mirror Lock- Up, Use it. Then you’ll load them on the computer, and In your photo editing program, Use the Negative Image function, to make the Negative image positive, and proceed to play around with the recorded Image.
Generally, the bigger the negative, the better the result will be. Scanning via a scanner will yield sharper, bigger, and more detailed results simply because everything is in focus and its a scanner, but the quality might not be as good depending on the scanner (e.g. you will see streaks/lines on your negatives), but I imagine if you have a slightly better scanner than mine, so, that should fix that problem.) Scanning through a digital camera, usually creates better quality instantly. But, the variables are: ‘How flat is your negative?’ and, ‘How flat is the lens pointing at your negative?’ Also, using a camera is sometimes less frustrating, as it works faster, in a way. In conclusion, both methods WORK. When it comes down to it, you can use either method to scan and preview your negatives, or even use the resulting images to showcase online (depending on the quality), with what you already have, and for free.
There are people who use their cell phone as their light source on a scanner. If you can adjust the brightness on the scanner display, it will work better. There is a downfall to that, as well because you may also scan the LCD pixels on the cell-phone screen.
Now, Be creative.