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I'm thinking of writing a new program. I haven't decided whether it would be added to my Handy Converter program, or be a stand-alone program of its own.

Here's how it would work -


1. You would load any image you'd like. It could be a photo or drawing of a locomotive, boxcar or building. It could even be an aerial view of the Tehachapi Loop, or a drawing of your layout.

2. You would have to know one dimension, such as the diameter of a wheel or the length of the locomotive. This would become the reference dimension.

3. Once you defined the reference dimension (by pointing to its end points on the loaded image) you could then determine the dimension of any other pieces or parts that you'd like. It wouldn't be necessary that the unknown dimensions be perfectly horizontal or vertical, they could be at an angle.

Would this be a useful program? I'm not even sure I could make it work as I've described, but before I devote effort to it I thought it would be a good question to ask!

I would appreciate your feedback on this. Thanks.
 
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it definitely would be exacter than my method of holding a ruler on the screen and using a calculator.
 

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Posted By stanman on 04/22/2008 8:23 PM
I'm thinking of writing a new program. I haven't decided whether it would be added to my Handy Converter program, or be a stand-alone program of its own.
Here's how it would work -


1. You would load any image you'd like. It could be a photo or drawing of a locomotive, boxcar or building. It could even be an aerial view of the Tehachapi Loop, or a drawing of your layout.
2. You would have to know one dimension, such as the diameter of a wheel or the length of the locomotive. This would become the reference dimension.
3. Once you defined the reference dimension (by pointing to its end points on the loaded image) you could then determine the dimension of any other pieces or parts that you'd like. It wouldn't be necessary that the unknown dimensions be perfectly horizontal or vertical, they could be at an angle.
Would this be a useful program? I'm not even sure I could make it work as I've described, but before I devote effort to it I thought it would be a good question to ask!
I would appreciate your feedback on this. Thanks.




I have heard of programs that do this already, but I don't know any specific names right now. I think I remember that they were rather expensive!

You would need the user to define at least 4 points because the "object" being meausured will most likely not be perfectly parallel to the plane of the image. You would have to take into account the depth of the image.

As a matter of useability (to me, anyway) the selection of the measurement points needs to be "adjustable" after the initial selection... with a zoom mode to help select the "exact" points.

I have tried to do this myself using various photo editing programs and Microsoft's own Windows Paint program and it sometimes helps, but too often it gives erroneous values because of the depth of the image... i.e.: suppose I measure a wheel on a locomotive and then try to measure the diameter of the smoke stack. Even if the Loco is perfectly parallel to the image plane the smoke stack is farther away (by about 2-ft.) and that then changes the dimension.

But if you can overcome those limitations, I think there would be several modelers that would LOVE a program that does it!!!
 

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That would be fantastic, I currently do that with a calculator and a book on trig cause I can't keep all those formulas in my head any more.
 

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You can do that in Quark Express. Just set two lines the distance apart you want, then import the image and resize until the object in question meets the two lines. In fact, you can do vertical and horizontal independently if you are dealing with a picture.

John
 

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Stan

that's a good idea for a program, and would be a nice addition to your product line either as an addition to your HandyConverter suite or as a stand-alone product. yes it can be done.

For example:
If you purchase either the[*]Locomotive Cyclopedia
of American Practice
Sixth Edition - 1922[*]Car Builders Cyclopedia
Tenth Edition - 1922[/list]From Rail Driver on either of the CD/ROM's there's a program named Scale Print that does exactly what you describe.

Plus here are a couple of links to 85A Models' Templot web site where they give examples on how to use the GIMP graphics editing program, which may give you some ideas on how to incorporate perspective correction in the application too.

Perspective Correction Tools - Rail Wagon, measurements from photograph

Perspective Correction Tools - Track Work, measurements from photograph
 

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I love sketchup. Download is free.  The learning curve is relatively short and once navigated, productivity skyrockets.  There are loads of tutorials on youtube.  Great advantage is that it works in 3D.  You can REALLY see what you are modeling by rotating and viewing it from all angles.  The only thing I haven't figured out to date is how to model landscape grades.



It's a snap to import a diagram or picture and then scale it.  There is a tape measure tool that works as it name suggests AND provides a scaling function.



I am currently building the Master Class Porter but with some freelancing. I'm currently building (almost dun) a wooden cab. I use Fletch's (most excellent) PDF templates. I save them as jpgs:







I import them into Sketchup, use the tape measure tool (as above) in the 'scale' portion. Then I know the size of all the original pieces and can free lance accordingly :)" border=0>.



Sketchup also provides an export function so you can save portions of your design as jpgs for printing and sharing.  My wood cab as designed:










Feel free to look at the other pix in the folder. You can see how ever piece of the cab is provided in great detail:







If you download and install Sketcthup, you can see/download the entire cab design.



I also used sketchup to design a Howe Truss bridge:







The bridge is dun:







..but not the umbutments.








john
 

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Discussion Starter #11
Thanks for all the info and replies!

I've been on vacation for a few days and have thought about the program some. It looks like a pretty tough thing to code, but I'll play with it for a while and see what happens.

It certainly won't be QuarkXPress! That wonderful softare retails for more than $600; my thought is less than 20 bucks for my thing.

The Scale Print program is not Vista compatible, and there's no plan to remove this limitation. I would make sure my program runs on all versions of Windows from 95 through Vista.

I'll let you know if I "get 'er done", and might have to ask another question or two along the way.
 

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Stan,
Would this be a robust version of your Scale Converter program, which I have and use often? I think I have version 7.0.0. I really like it and find it useful.
 

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Stan,

The capabilities of scale print go beyond just scale take off. You can also input an output scale and print full size in scale. That's pretty useful. With 1 known dimension I can print 1:20.3, or 1:24, or 1:32 scale output then tape them together.

Here's something it doesn't do that I suggested to the authors. If your photo is a perspective shot, you can't take off based on perspective. But if you know two horizontal dimensions or two vertical dimensions you could calculate the actual takeoffs at any point along the perspective photo. For example, If I take off the photo's vertical diameter of two drivers that are the same known actual diameter, and I know their distance apart on the photo, I can calculate the speed at which the takeoff changes scale per horizontal or vertical inch. From that information, I could take off dimensions anywhere on the perspective photo and convert them to actual.

Because many of our prototypes are old photos that have a perspective element to their scale, the perspective issue is a pain to deal with manually. I wrote a modeling article describing how to do manual takeoffs as part of the modeling series at the old MLS site.

I'm not interested in writing code. But I'd be willing to help with the concept if you are interested.

Tom
 

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Discussion Starter #14
Carl - I don't know whether or not this could be added to my Handy Converter program or not; it depends on how complex it becomes. It might have to be a stand-alone program.

Handy Converter is presently at version 12.3.1. Check out the info at http://stanstrains.com/SoftwareHandyConverter.htm to see what's been added since your version.

Tom - thanks very much for your offer of help. I've got some basic things to solve before I get to solving perspective, so it will be a while! Right now I'm struggling with scaling a picture (which could be any size) to fit within a fixed display area.
 

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Stan,
I downloaded and installed version 12 this morning.
 
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Stan,
I feel the systems should be a go. With the Handy Converter things have been much easier for myself. It is worth a try!
Toad
 
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