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Author Topic: Scale, volume, surface area on discrete object (not a mapped surface)  (Read 2715 times)

DCK

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FYI I use PS Professional edition, v. 1.0.4....

SETTING SCALE: I took a bunch of images with scale bars affixed to the turntable. I'd like to use these scale bars to set scale on the object itself.

Questions:
1. Do I place the markers on the scale bar in the photos themselves?
2. If not, I guess that means I need to model the scale bar as well as the object, and then place the markers on the scale bar, yes?
3. If so, in how many photos do I need to model the scale bar?
4. If I have more than one chunk, do I need a separate scale bar from each chunk?
5. Alternatively, I could place markers on the model of the object, measure the distance between those locations on the object itself, then set scale by scaling the object to that distance between markers. In fact, this is the approach I have currently taken. Is this as accurate as using the scale bar? Let's say I take three measurements on the object itself. For simplicity, let's say I take a length, width, and height measurement. Each measurement has error. If I place markers on the model to replicate these three distances, because of measurement error, each distance will suggest a slightly different scale for the object. How does PS handle these conflicting scale measurements? Averaging?

SURFACE AREA AND VOLUME: Having set scale for my object using a single measurement, in the manner described in question 5 above, I would now like to estimate surface area and volume for my object. To do so, the PS Manual instructs me to choose the "Measure Area and Volume" from the Tools menu. My tools menu does not have a Measure Area and Volume option. Where is it?

Screenshot attached. It's a metatarsal (toe bone)... get your mind out of the gutter :)

Thanks.
« Last Edit: October 04, 2014, 12:42:36 AM by DCK »