How do you measure the exact size of a sign that is high up in the air?

[Johnny Best]

What kind of camera and lens do you use. As far as getting far back, you can get a easier estimate of the sign height by the old method of measuring 6' up on the sign post and making a mark. Go back some distance and with a pencil measure that distance on the pencil and keeping your finger on that mark and moving it up as you go the next part will be 12' and on and on to the top. Not very accurate but an estimate as a photo would do. I think the long measuring stick as Moze showed would be better instead of tripod, camera and Photoshop. And getting all that equipment jacked out of your truck while your in Burger King getting that $6 Whopper meal, the pencil can be in your pocket.

 

[kcollinsdesign]

What kind of camera and lens do you use. As far as getting far back, you can get a easier estimate of the sign height by the old method of measuring 6' up on the sign post and making a mark. Go back some distance and with a pencil measure that distance on the pencil and keeping your finger on that mark and moving it up as you go the next part will be 12' and on and on to the top. Not very accurate but an estimate as a photo would do. I think the long measuring stick as Moze showed would be better instead of tripod, camera and Photoshop. And getting all that equipment jacked out of your truck while your in Burger King getting that $6 Whopper meal, the pencil can be in your pocket.

Ha ha! That pencil method is the same as my fancy-schmancy photo method. It's really nothing more than a triangulation formula from level 1 geometry.

For equipment, I use an old Canon Elph 100 HS which maxes out at (35mm equivalent) 112mm. It gets the job done. I have better cameras and lenses, but this easy to use and inexpensive point and shoot is what I use for most surveys. The most important thing about it is that the zoom is optical, not digital. Optical changes the focal length of the lens, digital simply crops the image.

I've seen that 40' long measuring rod, but it seems expensive to me. I'm sure it's worth it, but I just haven't gotten to that point yet. I have a bright orange 4' plastic level I throw in the pix for a vertical size reference (at minimum, usually I will measure something longer and write it down).

 

[kcollinsdesign]

I had an Estes Rocket altimeter when I was a kid. You would site down it then pinch the string when the rocket reached its highest point. Then you would cross reference the measurement to a chart that had columns for how far away you were from the launch pad (50', 100', etc.). I have no idea how accurate it was, but it was cool. I'm guessing it was accurate as long as your rocket went straight up!

 

[Texas_Signmaker]

You can measure the tops of signs on Google satellite view...its scary accurate and if you know the width you can figure the height

 

[Moze]

wow....pricey!!!

Texas_Signmaker They are pricey, but if you do a lot of surveys, they pay for themselves quickly. I just finished a bunch of bank surveys in West Texas. Preliminary surveys, no exact dimensions needed, just approximate. For pylon signs, channel letters, etc., it's super quick to walk up, extend the pole and get the overall height. Then bump it up against the bottom for the clearance above grade which will also give you the cabinet or letter height. I've been using them for about 15 years and can't imagine not having one.

 

[Bobby H]

Regarding the use of cameras and different kinds of lenses to use photos alone as a survey tool: that's even less reliable than using a tool like Spike. The Spike tool takes into account the combination of distance from the sign along with the kind of lens being used to take the photo. The main problem I have with Spike is it's only as good as the camera and screen being used. Spike on an iPhone is kind of lousy; I think it works better on an iPad. If you're just using a photo on its own with no numerical measurements of distance and perspective correction you're going to be spit-balling to some degree. Even using a high quality, perfectly distortion-free 50mm prime lens on a good DSLR won't provide blueprint accurate results. The effects of view point, perspective and fore-shortening all come into play to throw off the accuracy of measurements. When analyzing an image the farther you get away from the center of the image the more the any would-be measurements would be thrown off by the effects of perspective. We don't view the real world isometrically. There's tricks to shooting pictures of things like buildings in near isometric fashion, using tilt-shift lenses, but that actually distorts the image.

For some projects there's no substitute for measuring by hand. We're doing a lot of store front window wraps these days. For the imagery to appear seamless across a bunch of different window panes and for installation to go off without a hitch LOTS of field measurements are needed up front. We not only measure all the window panes, but measure all the divider bars and overall dimensions that way all of the window hardware can be accurately sized and coordinately positioned across the layout of the store front. When all of that is done correctly up front and laid out correctly in the computer the installation of the graphics will often be a breeze.

 

[Texas_Signmaker]

I think the consensus is, there are many ways to estimate the size of a sign in the air, but only one way to know exactly. Just don't estimate what you exactly need.

 

[Rob G Momentum]

wow....pricey!!!

I end up paying double for that for a 4 hour rental in DFW. Where do you rent from?

 

[Texas_Signmaker]

I end up paying double for that for a 4 hour rental in DFW. Where do you rent from?

Don't call the big guys like Sunbelt or United Rental...total ripoff. Call locally owned companies, their prices are more realistic. I'll usually find tow-able lifts (either 36' or 50') for $160/4hrs or $230/day. Not sure what side of the Metroplex you're on but Taylor Rental in Plano is reasonable.

 

[d fleming]

Short of using a lift to do exact, which you should do before making pans anyway, I have a friend who uses a drone for site surveys now. It's crazy how accurate that thing is. He doesn't even get out of the truck, lol.

 

[bannertime]

Don't call the big guys like Sunbelt or United Rental...total ripoff. Call locally owned companies, their prices are more realistic. I'll usually find tow-able lifts (either 36' or 50') for $160/4hrs or $230/day. Not sure what side of the Metroplex you're on but Taylor Rental in Plano is reasonable.

Before we needed to buy our lift, we setup a trade account with a local rental place. We did banners and self-promo stuff for them and were able to get a lift as needed. We still have the account, but our lift does about 98% of the stuff we need. I know it's not always possible, but that worked out really well for us.

 

[Texas_Signmaker]

Before we needed to buy our lift, we setup a trade account with a local rental place. We did banners and self-promo stuff for them and were able to get a lift as needed. We still have the account, but our lift does about 98% of the stuff we need. I know it's not always possible, but that worked out really well for us.

Yea I tried that with the company I use, but they use the company that I USED to work for...lol. I spend about $6k a year with them and tried to talk them into giving me a discount but they were stubborn.

Eventually I'll get my own lift... but I work from home and live in a neighborhood with alleyways which means I can barely fit my work truck in the driveway as it is... even with my small trailer jammed up against the side of my house.... DFW has such tiny lots Even the million dollar houses around here have about 5' of space between each other.

 

[Hero Signs]

I paid others for site surveys, years ago before I bought my bucket trucks. We have surveyed past our 50ft reach and have used the fiberglass rods for billboards to measure. Also one I taped a rope every 1 ft and threw over the sign and jiggled it till I got a measurement. Got to call around and talk to others in the trade and find the other wholesale friendly companies.