Author Topic: Getting dimensions with photoshop?  (Read 993 times)

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Chris333

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Getting dimensions with photoshop?
« on: August 22, 2016, 11:47:23 PM »
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I was wondering if any of the Photoshop pros here might be able to help me size a locomotive from a photo.

All that is known about this locomotive size wise are the drivers, they are 31" dia.

Original photo


My attempt to straighten it out and size it with a ruler.
« Last Edit: August 23, 2016, 02:24:02 AM by Chris333 »

Iain

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Re: Getting dimensions with photoshop?
« Reply #1 on: August 23, 2016, 10:45:00 AM »
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I'd drop that photo into autocad, draw a vertical line on the middle driver, and resize the image (and the line) until the line is 31".  That's what I did for my NS 2-8-4 project.
Thanks much,
Mairi Dulaney, RHCE
Member, Free Software Foundation and Norfolk Southern Historical Society

http://jdulaney.com

Chris333

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Re: Getting dimensions with photoshop?
« Reply #2 on: August 23, 2016, 02:03:47 PM »
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Was just wondering if there is a way to flatten the photo out some more. It is not a direct side shot.

wcfn100

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Re: Getting dimensions with photoshop?
« Reply #3 on: August 23, 2016, 02:25:16 PM »
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Here's trying to take any distortion out with the PS Lens Distortion tool.



But the effect of the perspective on the width are still there so I stretched it out about 10% to get the loco wheels more rounded.





Not sure if it's useful, but it's what I got.  Shot's with this much perspective are hard (for me at least) to get looking perfect.

Jason

dougnelson

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Re: Getting dimensions with photoshop?
« Reply #4 on: August 23, 2016, 03:17:40 PM »
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Not an exact science measuring of a grainy perspective photo, but here it is after rectifying in photoshop and converting to N scale.  drawing is full size N scale, measurements are in feet:


Chris333

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Re: Getting dimensions with photoshop?
« Reply #5 on: August 23, 2016, 04:34:31 PM »
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Thanks guys! that is what I was looking for.  I don't know if I'll get to model the driver wheelbase perfectly, but now I can get the whole shape right.

Chris333

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Re: Getting dimensions with photoshop?
« Reply #6 on: December 28, 2016, 02:57:52 AM »
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Just so no one thought this was for nothing.  :)

After printing out the outline to HO scale and playing with it. I noticed it very closely matched drawings I have for SR&RL 2-6-0's. Their 2-6-0's were later re-built into 2-6-2's and had their cabs pushed back. Also outside frames because 24" gauge. But the driver dia. and spacing matched. And the cab panel detail matched as well. Lucky me I already had etched parts for that loco.

The Sandy River loco:
https://maineon2faq.files.wordpress.com/2013/03/dmlrhs01.jpg
Take the pilot wheel off and push the pilot back. Push the cab forward and bam.

So I took my parts and started this:



The chassis is a Kato C12 2-6-2. I'm not going to try the 3 axle tender. Would rather have 4 wheels picking up power.

Just slowly messing with this. Runs well "as-is" .
« Last Edit: December 28, 2016, 03:00:36 AM by Chris333 »

aikorob

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Re: Getting dimensions with photoshop?
« Reply #7 on: December 28, 2016, 05:23:08 PM »
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in the original photo, the diameter of the front tender wheels seems larger than than those on the rear truck-----could the builders have taken the loco pilot and re-purposed it?

Chris333

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Re: Getting dimensions with photoshop?
« Reply #8 on: December 28, 2016, 06:05:37 PM »
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I can't find photos of it, but I've seen other 3 axle tenders before. Plus Mann's Creek had 2 identical 0-6-0 locomotives.

Caveman

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Re: Getting dimensions with photoshop?
« Reply #9 on: January 23, 2017, 08:58:40 AM »
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I use GIMP instead of Photoshop, but it sounds like what you are looking for is the "perspective" tool. Photoshop may have a slightly different name for it.