Some days, what makes me a scientist (and not just some guy walking around with a camera) is the placement of scales in photographs. I've taken many shots that would have been really beautiful were it not for the scale, which might be anything from the palm of my hand or tip of my boot, to a notebook, or even various types of things actually intended to be scales.
Typically, scales mark 1 to 10 cm intervals (the metric system being what allows American scientists to call themselves scientists) with bold black and white contrasts maximizing visibility in all sorts of conditions. Intervals and overall size vary, and there are multi-functional options with North arrows or caption boards. You can spend a bunch of money assembling a bevy of scales to cover all your needs.
Or, you can make one. That's especially easy if you use a Marshalltown 45-5 trowel, like many of us already do. On mine, anyway, the wooden handle is 10 cm long. I wrapped half of it and the metal ring in masking tape, measured and cut out two 1 cm bands, and spraypainted the handle black. Removing the remaining tape, and I had a scale for artifacts, features, profiles, and pretty much anything short of landscape shots. It's not got millimeter precision, and I wouldn't use it to draw an excavation profile, but as an expedient scale for survey photos, it's great. It extends the trowel's extant function of North Arrow and improves the effectiveness versus the unadorned trowel, which archaeologists will toss in for scale pretty often anyway.
As slick as I think the trowel-scale is, I'll admit that my other photo scale most definitely is not. The idea is neither original nor flawed: saw a dowel to 50 cm, and mark intervening 10 cm increments.
It's the execution that fails in this case. Instead of taking the time to tape and paint, I just whipped out a marker and filled in the 2nd and 4th intervals (for no other reason than that being the easier and cheaper option). As the sharpie ink bled, precision suffered, and for some reason all I had was blue, which is clearly less scientific than black. It's a sup-par instrument, but then again it does what it has to for the scales when I use it. I guess that explains why I haven't fixed or improved it in a year.
This post seems not to be about archaeology in Olympia. But field gear is part of archaeology, and fieldwork often calls for improvisation, so I don't think I'm too far off topic, especially in a town that takes DIY a lot further than typical American towns do. I know a home-made scale will cause some eyes to roll when they see my reports or site forms, but not before they register the scale of the photo, which is all that matters.
If you're another archaeologist who wants to make your own scale instead of paying a corporation for one, remember what I said about trying to use a sharpie (did I mention that sharpie wears off of a trowel handle in no time flat?), and go for it. Plenty of people already do for photo sticks. I'm the only one I know with a trowel-handle scale, but hope that people will copy the idea, because it's easy and makes sense. Just don't try and patent it and make people pay for it, or I'll be forced to point out that you saw it here first. If you do make one and like it, send me a photo of it at work sometime.