I am all for digitizing everything, photos, letters, anything that interests me, etc. to reduce the amount of albums and things around my home. I am even for digitizing old photos, postcards, etc. at OHA, and the thought of the “ancient” art of analog microfilm really grosses me out.

And then I attended a seminar given by Toya Dubin of Hudson Microimaging, Inc. At first I wasn’t totally convinced about microfilm and microfiche (who likes to go the library and be told they have to search an entire roll of microfilm to *maybe* find what they’re looking for anyway) until she showed us these numbers:
1 pixel at 600 dpi is 1/600th of an inch wide, or 40 microns wide.
1 silver halide crystal is 0.1 micron wide so 160,000 silver halide crystals will fit inside a 600 dpi pixel.
Holy Silver Halide, Batman! Not only this, but microfilm / microfiche has an expected lifetime of 500 years, with a known lifetime of 140 years - there’s some French microfilm that is still readable from 140 years ago.
Digitization is *not* considered a long term preservation method in most cases. Case in point, do you own any 5.25″ disks, and if so, do you have a computer that can read them? Remember the 3.5″ disks? My laptop doesn’t even have a 3.5″ disk drive - not only that, my previous laptop didn’t either, because I opt for CD / DVD. And speaking of DVD’s, you know that all of your DVD’s are considered old technology, right? While we race to keep our digital storage up to date, microfilm is still hanging around as the best preservation technology.
So the optimal solution is to scan the original documents from 600-3600 dpi and save them as tiff files, then use OCR to attempt to get as many words correct on each page as possible, manually correct the words that are wrong, and wah-la, you’ll end up with an index of your documents. The next step is to film the digital index onto the beginning or end of the microfilm, then film the original documents using 8-bit grayscale, especially if there are B&W photos. The end result? You’ll have an online, searchable index of the items that you are putting on microfilm / microfiche! And a roll of high-quality microfilm from which you can make a hardcopy.
Once you have your completed microfilm / microfiche, the next ideal situation is to store a second copy of all of your microfilm / microfiche in a storage location meant to store this type of thing (60 degrees F, 40% humidity) - ideally at a location not in the same flood plain where you have your original microfilm / microfiche.
One of the drawbacks of microfilming is you can’t do it in color for preservation purposes because color doesn’t last.
I also found out I should be scanning my Grandparents’ slides at 3600 dpi. I’ve been scanning them at 600 dpi. At least I knew to save them as tiff images. Sigh.
This doesn’t mean that I like microfilm any more than I did before, I guess I have respect for it now. I’m still going to digitize everything in sight.
Susan Gets Native on 29 Nov 2006 at 10:29 pm # edit this
Okay, I didn’t understand a single thing you said until you started talking about the screws. But it sounds like a busy day, anyway.
The MONY building: We have something sort of like that here in Cincinnati. The Chiquita building (yeah, the banana people) have different colored lights on the roof that change to tell people what weather is coming. (Which only works when it’s dark and if you live close enough to the Chiquita building to see it)
Pam on 30 Nov 2006 at 2:21 pm # edit this
Susan, the powerpoint presentation is like what you see at the movies (except better) with trivia questions and pertinent photos in between the questions and answers. It’s fun to put together.
Cool - I didn’t know if other cities had buildings that did this! Too bad you can’t see it. You can see the MONY tower day or night, near or far - because Syracuse is in a valley (which used to be a swamp, but that’s going back quite a few years).
Sandy on 30 Nov 2006 at 5:34 pm # edit this
What exactly is your job title, Pam? I agree with Susan, I didn’t understand most of what you did, but sounds like you do something with artifacts. Do you work at a museum or a library?
Warm here too, I was out this afternoon trimming grass along the front of the house, on the last day of November!
Pam on 30 Nov 2006 at 5:41 pm # edit this
Hi Sandy, I work at the Onondaga Historical Ass’n Museum & Research Center. I don’t really have a job title - yet - I just do whatever they ask me to do! I really enjoy working with all types of artifacts. It was fun going through their railroad china yesterday, since I love china.
The rain is coming this way - I just had to close most of the windows!