Hello folks,

Recently, I have mentioned in a couple of posts that Google Earth can be a useful tool for estimating distances and dimensions in the prototype that can be used to inform N scale modelling. For those that don't know it, Google Earth is a repository of satellite images from all over the world with an interface that allows easy access to these images. It is free and very easy to use. I live in Australia, but I'm modelling Canadian Pacific. Needless to say, when I need spatial information such as signal positioning, track separations, station layouts etc., it is not very easy for me to get out there with a tape measure to get the info I need. I'm not a rivet counter, but I would like to get my signal masts at least approximately the right distance from the track. With GE I can look at satellite images of any number of signals and get some idea where these signals are placed in real practice.

Let me illustrate with an example. The first following pictures is a Google Earth image of the CP Rail mainline just to the west of Banff (Alberta) station. The top of the red line shown is on the edge of the rail and the other ends at the base of a signal mast. The shadow of the mast can be seen clearly and it has two signal heads. The shadow of the ladder up the side of the signal mast can also be seen to the left of the main shadow meaning that the signal is facing to the left (west). The red line is drawn by the Google Earth measuring tool and indicates a distance of 2.5 m between the base of the mast and the nearest rail. The yellow line measures the distance between  the base of the mast and the frog of the points that represent the start of a passing track. This is 49 m.

[smg id=27993 type=preview align=center caption="Google Earth image of CP mainline - close-up view"]

The first picture below is a larger scale view of the same section of track. The positions of two signals are indicted by the green circles. The signal on the right shows the ladder shadow to the left of the mast so this signal is facing towards the right (east). Other features that can be seen are the shadows of the boom gates at the road crossing. I can use these images to get the approximate distances between my boom gates and the road. The third photo shows a photo of a CP Rail train hauled by two ES44AC locomotives passing a signal which I believe to be the one shown in the first Google Earth image. In other images, the shadows of the signals may not show up as nicely as they do in these satellite images, but it is generally still fairly easy to tell where they are.

[smg id=27994 type=preview align=center caption="Google Earth image of CP mainline - larger scale view"]

[smg id=27995 type=preview align=center caption="Ground view of first signal"]

Google Earth has certainly been a useful tool for me and perhaps for others as well.

Webbo

I didn't check Google Earth, but Google Maps often gives pretty good track plans in map view. You'd want to verify them against the satellite view and other sources/own observations but as a starting point they're pretty handy.

Interesting post - thanks for that.

Like RS, I've used Google Maps to help me with my scenic efforts. Following a tracks route through the towns and countryside can be a bit of fun.

Dave G

It is also a good source of pictures for positionally accurate backscenes - streetview for specific close-in stuff and even the normal (helicopter) mode for general (non-urban) terrain.

If you take a look at the Talyllyn, you can see a train halfway along the line (unless it's been updated since I last looked) 

Sorry

In the first GE image, I should have said that the shadow of the ladder is to the right of the shadow of the mast - I sometimes have a bit of trouble differentiating right from left, up from down, inside from out etc. You'll have to excuse me.

In virtual modelling I used it extensively, you can even extract the images to be the base of your virtual layout, this translates into hundreds of virtual miles...
in N however... all you said is quite interesting but all I can say is that Google Earth tells me how ridiculously small is my  layout and how little real things I could represent in that space... for example an IKEA store with all the parking space would cover the entire layout 

Quote from: Webbo on August 09, 2015, 07:49:31 AM
Sorry

In the first GE image, I should have said that the shadow of the ladder is to the right of the shadow of the mast - I sometimes have a bit of trouble differentiating right from left, up from down, inside from out etc. You'll have to excuse me.

Sorta like looking at anatomical diagrams and getting the left and right ventricles mixed up 

Or worse still, that surgeon who was supposed to remove a crook kidney but took the good one out! 

Quote from: Bealman on August 09, 2015, 07:57:34 AM

Quote from: Webbo on August 09, 2015, 07:49:31 AM
Sorry

In the first GE image, I should have said that the shadow of the ladder is to the right of the shadow of the mast - I sometimes have a bit of trouble differentiating right from left, up from down, inside from out etc. You'll have to excuse me.

Sorta like looking at anatomical diagrams and getting the left and right ventricles mixed up 

Is that the same place where mixed metaphors come from, George? 

Dave G

Bet the kidney guy didn't think about that, Dave! 

Not every satellite image is clear but the tool to enable you to look at historical images can be really helpful: click on the date in the lower left of the main image will bring up a sliding bar enabling you to select an image date.

Another valuable resource is the Britain From Above web site:
http://www.britainfromabove.org.uk/

Thumbnails of old aerial photographs can be viewed for free but there is a charge for accessing high resolution versions; currently £9.90 per online image for personal use, supplied at 300 dpi resolution.

I used GE quite extensively during the construction of Billingham. It was perfect not just for the overall dimensions but for the measurement of the surviving building's and also for their roof details. The birds eye view tool on bing's Multimap is another great way to find the information on buildings especially if there is no access to a particular elevation you desire to model.

An example of the fruit's of these internet tool's can be viewed on page 78 of NGS journal 4/15. You will find an image of The Station Hotel (back dated version) in model form and can be compared with the prototype at above said's online site's. Zip/Postcode TS23 2RH.

To consider I live locally I got away with not having to go out with an extra long tape measure,note pad and pencil.

Hope this is helpful.

John

Using the history bar on Google Earth (not maps) is very handy at times. I would be wary of the dates that are sometimes given. Looking at Westbury (Wilts) there is a given date of 1945. The imagery that can be seen for this date is actually pre 1942 (most likely summer 1941). This is evident as there are features missing from the photos that would have been very visible in 1945.

I use GE quite a lot in real life anyway, but between that and Streetview. it really is a fine modelling resource
The measuring facility is really accurate, so from the plan of a building you can work out the elevation dimensions without, s Jonner says, needing the pad and tape measure and the funny looks

I've been working with a bunch of grabs, from 'out in the countryside' street view, to make a back scene for my layout. Hard to locate the the Scotland/Wales border on Google Earth though......