Monthly Archives: May 2012

Measuring Heights Without A Tape Measure

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Here are three high-tech to no-tech ways to calculate the height of a building or tree or pole or anything else you need to know the size of but can’t determine with a tape measure.

1. Theodolite Pro

Theodolite Pro is an app for the iPhone, iPod Touch and the iPad.  Made by Hunter Research & Technology , it’s a multi-function augmented-reality app that combines a compass, GPS, digital map, zoom camera, rangefinder, and two-axis inclinometer. Theodolite overlays real time information about position, altitude, bearing, range, and inclination on the iPhone’s live camera image, like an electronic viewfinder.

At $9.99, it’s worth more than 4 times the price.

Theodolite Pro screen

The apps screen data gives you your position in either latitude and longitude or UTM units, as well as the time and date and your elevation. On each side are the horizontal and vertical indicators in tenths of a degree. The device has a one-button calibration function as well as a 2x and 4x magnification for pin-pointing a particular object. There are several options for the center crosshairs, one of them are a pair of multicolored floating boxes which merge and turn white when you are plumb in both directions.

You’ll get a much better result if you mount the device on a tripod. For an iPhone, the method I like is with a Snap Mount. It has 1/4″ female sockets for mounting in either a vertical or horizontal direction.

Snap Mount device for the iPhone 4

Once the phone is mounted, you point the center at the top of the object and push the “A” buttton to take a reading. Then tilt the device toward the bottom of the object and take  the “B” reading.

Then the app will ask you for your distance to the object. The more accurate your answer the more accurate the result will be. So, you’ll either have to pace off your position or measure the distance with a reel tape or laser measure device.

If this isn’t possible, you can use the option to determine the distance and height, although this will probably not be as accurate.

There is also an optical rangefinder built into the view screen that works by way of a series of concentric circles in either size factors or mils, that you can use to determine distance if you already know the size of an object in the foreground.

optical rangefinder rings

This app has been a best-selling navigational app for some time and has become a very useful tool in many different fields. You’ll find it’s very useful when doing field surveys and it’s certainly a lot cheaper than an analog theodolite.

2.  Clinometer

A clinometer, or inclinometer is a device which measures the angle of slope and uses basic trigonometry for estimating height. My clinometer is a combination clinometer and optical compass made by the Finnish company Suunto and is called the Suunto Tandem. Like the iPhone, you’ll get better results if it’s mounted to a tripod and the Suunto has a 1/4″ socket for this.

The Suunto Tandem

You look through the peep sight, leaving both eyes open. The graduated scale is superimposed over the object you’re centered on and you can read the results as either a percentage of slope or degrees of elevation.

You sight the top of the object in the device and read out the angle. Then you refer to the cosine table on the back of the device. From there it’s just a simple trig calculation. Adding the height from the ground to the center of the clinometer will give you a very close figure for the objects height. Like before you need to know your distance from the object you’re measuring, so it would be a good idea to determine your average stride to have a semi-accurate way of pacing off distance when surveying.

The back of the Tandem has tables of cosines and cotangents printed on it to make calculations easy.

The list price of the Tandem isn’t cheap, but I’ve seen them go for $20 on Ebay, so you should check there before you buy a new one. The results may not be quite as accurate as with the Theodolite app, but you’ll never have to worry about a dead battery and the device will still work perfectly 50 years from now. Like the Theodolite app, it’s good for shooting grades and taking elevation surveys as well.

A handy addition to both the above devices is to get a Keson Pocket Rod. It’s a collapsable surveyors stadia that rolls into it’s case. It has black and white graduated scales on one side and red and white on the other. It’s a great tool to have to put in location survey photographs as well for accurately scaling details from photos when you don’t have time to measure everything at a location. They come in both Imperial and metric units.

Keson Pocket Rod

3.  Biltmore Stick

This is the cheapest and easiest method of determining height but it’s also the least accurate. This is a trick I learned from my Boy Scout days. It’s based on the Biltmore Cruiser stick which is a way of determining the heights and widths of trees and how much lumber they would yield. The Biltmore Stick ( sometimes called a hypsometer ) gets it’s name from the famed Biltmore Estate in Asheville, North Carolina and was invented in the 1890’s by a German forester named Carl Schenk who was the master forester at the estate.

A real Biltmore stick has graduated markings that take into account for foreshortening but there’s a less expensive method. We were taught to use a yard stick (not very compact) or a 6 foot folding rule, which is a little wobbly to hold vertically. I like to use a Four Fold rule which is the original folding rule from the mid 19th century. They were sometimes called Blindman’s rules because the numbers are large and easy to read, making them perfect for this use. Garrett Wade carries a good reproduction of them. They fold down to just 9 inches long and fit nicely in a survey bag.

The way to use this one is to pace off 25 feet from the tree, building, etc. Turn and face it, holding the rule at arm’s length. 25 inches from your eye is the ideal distance. hold the rule so that the bottom of it lines up with the bottom of the object, like so:

using the Four Fold rule as a Biltmore stick

Read off the number than lines up with the top of the object and that will give you the height in feet. If the object is above the 25 inch mark, back up another 25 feet and multiply the results by 2. If it is still above the 25 inch mark, back up to 75 feet away and multiply the results by 3, and so on.

This method won’t necessarily give you a really accurate height, but it will give you a number that will be pretty close, say within 3% to 4% of the true measurement, providing you are very close in the distance increment and the rule is very close to 25 inches from your eye.

 

Digital Disasters – How Toy Story II Almost Disappeared

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You’ve experienced it. That punch in the gut when you realized the file you spent days on is gone, just gone. You have copies, great. Um, they’re corrupted. You panic.

Welcome to the wonders of the digital world. The first time it happened to me I couldn’t believe it. It just seemed impossible files could disappear and backups be corrupted or unopenable. Now I back up to two different drives at work and another at home, and I’m still paranoid.

The “experts” now say you should do several things to protect your digital media:

  1. Be sure your files are backed up in multiple places, at least three.
  2. If you buy the same brand of hard drive don’t buy them all from the same retailers: manufacturing glitches can show up over all units from the same batch.
  3. Rotate your drives and upgrade to new media regularly. Those CD-R’s from 12 years ago may have data problems from information loss.
  4. Have a sense of humor. You’ve traded speed for longevity. That’s the way it is. Example: the average Daguerrotype will last about 10,000 years, meaning there will still be plenty of 1850’s portraits around thousands of years after every photo from this century, and most likely the next, are toast.

Share your horror stories here. You’re among sympathetic listeners. Thing is, I just can’t ever remember the graphite mysteriously disappearing from a vellum drawing. Just saying.

And lest you think it just us, watch this little film about how Toy Story II almost disappeared into the digital ether along with your files.

Sculpting Tools For Sketchup

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Most people think of Sketchup as a program that just draws boxes. As a poly-modeler it was always handicapped when it came to modeling compound curved surfaces and even with the built-in Sandbox tools, drawing terrain was never truly easy.

Now there are two different plugins that make not only terrain construction but organic and vehicle construction possible without having the urge to jump out the nearest window. I use both regularly and because they each have different attributes, I think their capabilities really complement each other when you are constructing complex shapes.

Artisan

The first is a plugin called Artisan which is a great solution for creating organic shapes. Created by Dale Martens, who has produced numerous other free plugins including Subdivide & Smooth, has created a set of sculpting tools that work very much like the sculpting tools in Maya and are incredibly easy to learn and use. The site has nice tutorial videos as well as a nice gallery of others work using the plugin. You have a series of settings which allows to to adjust the pressure of the brush, either positive or negative, and after setting the width of the ‘brush’, you drag it over the area to create the sculpted surface. The demo video below will give you an idea of the process.

One of the tools that alone is worth the $39 cost, is a poly-reducer which is a huge help when you import models from a NERB software package like Rhino or Maya. The tool allows you to select how much you want to reduce the poly count of a model to get it down to the size you need. You can also reverse the process and take a low-poly model and increase the detail.

I consider this plugin to be an absolute must for people who want to be able to build anything besides flat walls in Sketchup. Here are some examples of Sketchup models created using Artisan:

scooter by Pete Stoppel using Artisan

Motorbikes by Pete Stoppel

creature by Erik Lay

terrain by Pete Stoppel

Vertex Tools

The other plugin is called Vertex Tools. This program has tools which work differently than Artisan but has some advantages over it in the way the selection tools work. Designed by Thom Thomassen, a modelmaker from Norway who has also designed an incredible number of other useful free plugins, has designed a set of tools that are what the Sandbox Tools aspire to be.  At $20 it, like Artisan, is a real bargain. The video below will give you a quick overview.

The selection tools allow you to set how the tool affects the surrounding polys with either a linear or cosine fall-off. This one is really a must when you are creating terrain.

At a total cost of $59 dollars, these plugins will give you a huge boost in your modeling capabilities. If you use Sketchup, they should be your next purchase. You won’t be sorry.

A “Sweet” and Cheap Architectural Detail Resource

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Yes, I thought it was time for a bad pun. The “sweet” resource I’m talking about is the Sweet’s Indexed Catalogue of Building Construction. Not the modern version, mind you, but the earlier volumes. In particular I’m talking about the first one ever printed, in 1906.

Reprint copy of the first edition of Sweet’s

I found my copy in a used bookstore about 25 years ago, back when 3rd Street in Santa Monica was still a sleepy street lined with great used bookstores instead of chain outlets. It was a 1970’s reprint of the original, in great condition. But the most striking thing about it was how different it was from it’s modern relatives. This book was printed for people who actually drew details, and both wanted and needed to know how things were built.

Most of the products pictured throughout the book had either detailed drawings or photographs of the items, with dimensions and cutaways showing how they operated and how they were integrated into the architecture of the building. This was a far cry from the ‘updated’ version, void of details, which was meant only to be a means of calling out the correct ‘part number’ on a drawing rather than giving the architect a full understanding of the specifics.

The original volume, if you can find a copy, has a green cover. The reprints will have a tan cover. The most useful ones for our work run from 1906 to the 1930’s. They aren’t easy to find but Google has solved that problem. Among the millions of books they have digitized for their ebook site are the 1906 and 1907 editions of Sweet’s. The digital editions aren’t as crisp as a printed copy, but the details you’ll glean from them are priceless. You can download it as a pdf and have it on your computer whenever you want to refer to it. Here is some of what you’ll find:

A sample of a typical advert featuring both photos and detailed sections

details of furnace and ducting showing how the duct and registers are attached to the wall framing

One of hundreds of photos showing details such as trim, ironwork and tile.

Detail of large furnace for an office or apartment building

An early central vacuum system

And here’s proof that people had MUCH bigger heads 100 years ago

Another good source in Google Books is a magazine from about the same time period called The American Builder which has some good articles with details. This ad for a drafting course is great. Considering an average draftsman would have made about 35 to 40 cents an hour at that time, $100 a week would have been top dollar.

What’s Wrong With The Film Industry?

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Photo by Mike Finklestein via Flickr

Following the ouster of Rich Ross as chairman of Disney Studios, UCLA Professor Emeritus Howard Suber posted a recent article about an influential investor who wrote a report to the Paramount Studios board entitled, “What’s Wrong With The Film Industry?”

Here are some of his main points:

-The constant turnover of the production head of the studio is disastrous.

-The conflict and turnover caused by the buying and selling of companies causes          confusion, uncertainty, and weakens morale in the production areas.

-Authority is not clearly defined.

-Overhead is indefensibly high.

-Budget estimates are not complete or accurate when shooting begins.

-Budgets are a joke, since they are exceeded with impunity.

-Shooting schedules are disregarded; scripts are not ready when shooting begins.

-The write-off on stories and contracts is enormous. Screenplay costs are excessive.

-Producers hold exorbitant contracts, and there is no relationship between a producer’s salary and the box-office success of his pictures.

The analyst concluded that it would probably be a smart move to put someone in charge as Head of Production who actually had extensive film-making experience.

The analyst was Joseph P. Kennedy, father of J.F.K., who was involved in both Pathe and RKO. The report was written in 1936.

It’s hard to know whether to be surprised, disheartened or amused that so much hasn’t changed over the last 76 years. It will be interesting  ( or gut-wrenching, depending on your mental vantage point ) to see where it all leads us.

Will the continuing tide of runaway production be Hollywood’s final undoing, or are we all on a big merry-go-round that brings us back to the same spot with a calculable regularity?

Suber writes an excellent blog entitled The Power of Film where he posts some very insightful articles. Check them out.