Category Archives: aerial

Streetscape Methodology

This is a screenshot from AutoCAD: The lower image is a series of rectified, scalable images of the east side of Augusta Street in Staunton, VA - with an aerial view of the same street grabbed from Google Earth inserted above.

This week I have been developing a methodology for capturing and representing a large volume of structures quickly as I will be doing a project charged with just this task next week in the Russian sea port city Vladivostok. Above is the sample streetscape I created using Augusta Street in Staunton as my test subject.  The photography work took about 15 minutes. I did not use a surveying rod as I typically do, nor did I collect control dimensions with my laser.  In stead, I scaled my model using dimensions extracted from satellite imagery available on Google Earth. I was looking to find a way to obtain accuracy sufficient for 1:200 prints that was also very fast.  To check my work I measured a distance from the model prepared in this way and checked it with the real world conditions. Incredibly, the error was 1/4″!

Scalable at 1/16"=1'-0" when printed at 300 dpi

Above is an individual image extracted from the group that comprises the streetscape. As noted the photo will behave like a measured drawing at the ratio of 1:192 when printed at 300dpi – which means that it is 1:96, or 1/8″=1′-0″ when printed at 150dpi and so on… My opinion is that this is very good considering how fast I made myself complete this work!

The streetscape in my test project represents about 1,000 linear feet. It will help me to extrapolate what can be achieved when tasked with documenting an entire historic district under tight time constraints.

Telescoping Tripod

Using my telescoping tripod in Renssalaerville, NY

Using my telescoping tripod in Renssalaerville, NY

Over the summer I started a business venture with a friend doing aerial photography with his 1946 Cessna. I do the photos, he does the flying… Anyway, this experience got me hooked on the possibilities of enhanced points of view.

For a long time I’d thought of the cherry picker (aerial lift/bucket truck, etc.) as my only option and had often worked around the lack of great points of view with creative alternatives when budgets and such would not allow the use of a cherry picker.  But, being hooked as I was, I did more research and realized that a relatively low cost solution was available which could yield surprisingly good results – if you have the guts to put your calibrated camera up in the air on a telescoping tripod.

Even if you purchase a well made tripod with adjustable legs that allow the whole rig to be leveled, and even if you attach guy wires to stabilize everything ( if you have the need plus the manpower), even so, it takes some nerve to put your specially calibrated SLR way up into the air!

Of course its range is nothing compared to a big boom lift, but it can let you see over cars and trucks, and bushes and fences and all sorts of things.  Its just one more trick up your sleeve that can help your work become just a little better.

Aerial Photogrammetry

Massing Study from Aerial Photos

Massing Study from Aerial Photos

While I was working in France for Innova, we did some photogrammetry using shots taken from a helicopter. Some of this was mapping related for transportation studies, and some was more three dimensional in nature.  It is not a market that I have pursued here in the US – it was very difficult to do in those days and required a fair amount of support from ground based control data derived from theodolites and such.  Recently I did an experiment using an aerial photo that I shot of the Blackfriar’s theater in Staunton and integrated it into a photogrammetric model and found the whole thing considerable more accurate and easy to do than I rememeber it was 18 years ago. Shown here is a cut sheet from a project completed with Innova back in the early days.