In The Scanning Problem I gave my first, rather unsuccessful, experiments in converting 35mm negatives to a digital format. After I little more thought, I realized that my failed attempt with my flatbed scanner was for an obvious reason: negatives are transparencies and my scanner only scans reflective items!
After all, think about it — to scan a negative, it has to emit light, pass the light through the negative, bounce off the white cover, go through the negative again, and then get sensed! No wonder the images were way too dark!
I’ve looked into other scanners and they generally go for $150-$200. While I plan (hope?) to get one in the future, I promised my wife I’d hold off until it was clear that I was going to have a lot of film to scan. So, until then, I want a do it yourself solution that fits my budget.
And I think I’ve found a solution…
* * * * *
See, it turns out I already have a very high quality optical scanner at my disposal… my camera!
So, I set up a quick little experiment to see if the result was practical. Here is the setup shot:
The basic idea is to shoot a flash (Sunpak 383, the trigger is barely visible at right-center), forward through two layers of copy paper to make sure that it is very diffused and even. The second piece of paper is kept an inch away from the film to keep any texture in it out of focus. The film is mounted on a black colored piece from the back of a notebook, held by a Costco negative holder that has been sliced to give access. In hindsight, I sliced way too much off the negative holder, because it was incredibly hard to get the film in there securely and relatively flat. The holder was taped on, and a clip was used to keep the board upright.
With the flash firing, it looks like this:
I believe I was firing at 1/4 power at 100 ISO, using an old Canon 100mm f/4 Macro lens (FD mount). Not ideal, with more flare than I’d like, but it did the job.
And the film itself looks like this:
Not too bad, right? The film has a definite color cast to it, partially because copy paper has a slight blue cast, and I think my camera’s white balance got a bit confused. Actually, because of the cast from the paper and the lack of precision with this method, I would not recommend trying to do color negatives this way. Color negatives are notoriously hard to scan correctly, even with a good scanner.
Of course, the true test is how the scan looks. With a full frame negative capture, here is a 100% crop from the DIY scanned image:
For comparison, here is the scanned image I obtained from Costco:
The Costco image is clearly sharper with nicer contrast (although I bet I could improve the contrast in PaintShopPro pretty easily). But, the real question is, would it fit my purposes?
Absolutely!
I would estimate the effective resolution is around 2-4 megapixels — plenty for a 4 x 6 print, and way more than needed for web images. For example (click to see larger):
And, there are a number of improvements that I could do. Most notably the slide mounting, but also some more consistency in focus and flatness. So, I’ve got plans to whip up a better version of this nearly free DIY scanner — stay tuned!