Using photographic images to create scales for measuring their dimensions

[NW Mailing List]

My father taught mechanical and architectural drafting in high school and
assured me I would always be able to find employment using those skills.
Fortunately, he also taught me how to hang doors, for the same reason, and
his prophecy held in that case. 

The craft of drafting vanished fairly quickly in the wake of computer aided
design.  However, I remember from my own work at drawing boards encountering
the problem of dimensioning images like photos.  

Glass insulators like those shown in the photo taken at Boaz siding were
pretty much all the same height.  An enlargement of the photo would allow
measurement of those insulators.  That height can become the basis for a
scale that could allow measurement of all the additional visible attachments
to the pole, from which I suspect even its height, the main dimension that
is concealed behind the tree line, could be derived. 

Neill Herring, retired draftsman, Atlanta. GA