Tuesday, February 22, 2011

Tech Tuesday - Digitizing With Cameras, Part II

I apologize for the delay.  I had originally intended to write and publish this entry  for last week, but participation in a 50-hour Trivia Marathon over last weekend wiped me out.  Hopefully the wait will have been worth it!

I re-read the first part of this topic in preparation for writing this part, and I think I should revisit my comments on lighting.  Using your camera's flash is almost never a good option, and should be a last resort.  Any light that is at too small an angle to the lens opening will result in reflections and glare, which is why I used the reflectors at 45 degrees off.  That position is least likely to result in any reflections.  An external flash that can be bounced off of a white surface would possibly be a workable alternative.  Really, though, the setup I suggested will work best for very little money.  It's pretty much what professional copy stands have, in a poor-man's DIY version.  You might look at school auctions, they sometimes part with old equipment and might have a real copy stand for cheap.

Okay, having said that, and having somewhat described my setup in Part I, here's a shot of how I lay it out as an example:
Two DIY reflector lights on tripods, and a neutral colored base/background.

As you can see, I have the cheap reflector lights simply clamped on a couple of old tripods I had around.  They currently have GE Reveal incandescent bulbs in them, but you could just as well use CFL bulbs and save some energy.  (Incidentally, I've used these same lights for an impromptu photo studio to shoot portraits, they worked well enough for the purpose, given what I paid for them).  The black material is simply a bed sheet I got on sale somewhere.  You'll want to use a neutral color like black, white or grey, as opposed to a color that might alter the color of your materials.  When I did the Scrapbook for Part I, I had a white sheet of tagboard as my base.  I've laid the base on the floor, set the lights approximately the same distance from each side aimed about 45 degrees onto the desired area, set the object to shoot in place, and stood over it shooting vertically down.  It's important to shoot as close to vertical as you can manage, as any slant will give you a keystone effect to rectangular objects, like this:

Shot vertical - all sides parallel.

Shot at an angle - sides keystoned - slanted in to top!
You'll note the absence of reflections in this image - there is glass in the frame!  The 45 degree angle works.






















This example is pretty exaggerated to show you what I mean, but even slight keystoning becomes noticeable when you start cropping in for size, or to isolate images from a multi-image page.

As I mentioned before, you want to use RAW format if your camera supports it, or if not, immediately convert your image from JPG to TIFF before you do any editing.  Also, if your camera has a setting, make sure you set it for the correct white balance.  Incandescent bulb usually have a preset you can use, and fluorescent tubes do as well, but if you have CFL blubs in your reflectors, DO NOT use the fluorescent setting for those, as they're made to mimic the color balance of regular incandescent bulbs in most cases.  Use the incandescent setting instead.  Better still, if your camera allows, use a custom white balance for your particular setup and lamps.  Check your camera's manual for how to set the white balance on your particular camera.  You'll note the images of the picture in the frame above are somewhat yellow-looking; this is because I didn't set my white balance before shooting them, as I was only trying to illustrate the keystone concept, and the color was not important.

To illustrate white balance, I shot a family heirloom ring on a white background:

Heirloom ring on white background, Auto white balance.
The color of the incandescent bulbs makes the white background and everything else look yellow.  Then I set a custom white balance for my setup, and shot the ring again with no other changes:

Heirloom ring, custom white balance.
It really makes a difference and saves tons of post-processing of your images.  You could correct most of the color balance out with Photoshop, but setting the white balance up front saves all of that time and effort for everything you shoot. Also note that the ring is not entirely in focus.  I was shooting at a low f/stop number which results in shallow depth of field.  Normally this isn't an issue as you're shooting flat objects like albums, but a three dimensional object can cause problems.  I also shot the ring on a black background:

Heirloom ring on black background.
You can experiment with different backgrounds and lights to see what works best for the item you're digitizing.  You'll note that a black cloth background tends to attract and show lint and dust.  Have a vacuum handy!

This ring belonged to Sally Lommel, the same person who put together the scrapbook in Part I.  She was my wife's great-aunt.  The ring was an engagement ring from the one time Sally was proposed to; the marriage never happened, but Sally ended up keeping the ring.  This is an example of digitizing a three-dimensional object.  You might get away with this ring in a scanner as it's relatively flat, but anything with more depth would be hard to get on a scanner.  Also, on a scanner, you can't position objects other than flat on the platen glass.  With a camera, I could have devised a stand to set the ring upright for some different views.  I may yet do this at some point.  A ring box would be a good choice for that, if I could locate one of neutral color.

I've covered the basics of using your digital camera to digitize  things you can't get in your scanner.  If you have any questions, I'd be happy to try to answer them in the comments below.  I'm also planning to be on the next Scanfest this weekend, you might try catching me then.  If you have a specific item you'd like advice on digitizing, I'll do my best to tell you how I'd tackle it with the equipment you specify.

Missed Part I?  You can still read it here.

Tech Tuesday – Have you stumbled upon a piece of technology or new Web-based application that would be of interest to your fellow genealogy colleagues? Post at your blog on Tech Tuesday and show us the ins and outs of this technology and how it can benefit the genealogy community.  This is a new series suggested by Donna Peterson of Hanging with Donna and in the past there have been many iterations of this series: the National Archives and Records Administration (NARA) blog Narations as well as The Family Curator by Denise Levenick.  (Blurb shamelessly stolen from Thomas McEntee at Geneabloggers!)

2 comments:

  1. Daniel,
    Really like how clearly you are explaining this process, especially when you are including photos to demonstrate the process. I am finally catching on!

    Have a question- I read in latest issue about photographing microfilm that involves attaching the camera to the reader w/clamps, etc. Could you refer me to possible site which demonstrates this process in photos like you do? It also mentions using paper to block glare and makes no sense to me. Thanks!

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  2. Wow! That's a new question for me. I've never tried that, and I would think it would be difficult to get a good image that way. You're introducing a bunch of issues in the mix: distortion from the viewer's optics, the viewer's screen surface, possible lighting issues. Those viewers generally have poor contrast as well. You'd be much better off, if possible, finding a viewer with a built-in digitizer. I know not everyplace has those yet. My local public library has one, and it's a total joy saving the images directly to a USB drive to take home. The price is right, too, it's free to grab digitized images, where printing them is $.10 per page.

    I guess if there was no option, I'd try hand-holding the camera and do the best you can framing up the image in the viewfinder. And set for monochrome mode, no sense including color issues when the microfilm is almost certainly black & white.

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