awright all you photoshop gurus out there..

[jeffb]

is there a computer program out where i could scan a pic of a car, then produce 1/25th blueprints from? im gettin frustrated trying to find 1;1 cars to throw a tape measure on so i can make masters. or even something where if i have a pic, with one item of a known dimension i could extrapolate the rest of the dimensions? keep in mind, im really really stupid, and im a resincaster( terms are redundant). so therefore i have no cash to buy $700 worth of software,

or the brains to run something complicated. dont ask for much do i?

[Harry P.]

is there a computer program out where i could scan a pic of a car, then produce 1/25th blueprints from?

Short answer: No.

There's no such thing as "magic" software that will produce all sorts of information based on inputting a scan. It doesn't exist.

[RodBurNeR]

why not google the cars you want to get info on? you can find the wheelbase and all the schematics on almost any car if ya look hard enough. then you could scale it down with a scale calculator and yes this stuff is out there. (not a photo scanner like you want though)

[Zoom Zoom]

Nope, there's no magic cheap software to do blueprint layouts, if there was I'd already be using it and looking for the cheap/easy 3D program to carve stuff out from computer files...still a few years down the road before feasible on a hobby basis.

You can always scale your photographs or copies to make the rough cutout patterns. You can do them the old-school way using vellum paper and drafting pencils and circle templates and ship curves. That's how I've done the layouts for the various Hot Wheels cars I've worked on, a couple masters for resin (one '91 Crown Vic that was never finished, the MGB GT that I did for All American, the Toyota GTP car for BHP Enterprises). The computer is fast for a lot of things but drawing the complex lines of a car still seems easiest to me the old-school way (I can trace over a photo, whether on the drafting board or the computer).

[jeffb]

i guess i asked the question incorrectly. i know theres no magic wand to wave, ive already tried that and got kicked outta the harry potter convention. i remember a SAE artice years ago where they had a pic of a truck. they knew the wheel was X number of inches.. they then used a formula to figgure out the rest of the dimensions. that way if i know the wheelbase, or head lamp size, or what ever, i could sus out the rest. it dosent have to be in scale, just be able to find the numbers in inches or mm. i really dont need blueprints per se, just the measurements overlayed on a pic. i was fairly sure you just couldnt scan a pic then convert it to prints, that would be waay to easy.

[RodBurNeR]

http://lmgtfy.com/?q=scale+conversion+calculator

[Harry P.]

If you had a photo of a side view of the car, and you knew the wheelbase was, say, 116 inches on the real car, you could measure the wheelbase in the photo, do some simple math and figure out exactly what "scale" the photo was, and extrapolate the other dimensions. But you would need an exact, dead-on side view (or top view or front or rear view)... no perspective at all, as that would make the conversions impossible. But that has nothing to do with any computer software, it's just simple math.

[jeffb]

ah.. but theres the rub. the only simple math i know is how to spell "simple math". even then i need spell check. i guess i'll dig thru my old sae's and find the artice. the formula was in there.

[Foxer]

You are really just talking about simple proportions. But as Harry says above, perspective is always a monkey wrench is doing this. Even with a photo taken at right angle to the side of the car the camera lens and parts that are at different distances from the camera than the wheels you use for base measurement will not proportion correctly. Some factored adjustment would have to be made to account for the proportion distortion. Even so, I have done this many times when modeling to get basic dimensions for a part I have to make. The eye is probably more important than the exact scale to the fraction of an inch to get something that looks right. You don't want to even think about the math involved in correcting for perspective.

In any case, the basic math is very simple. Say you have a car with an actual wheel base of 100 inches. Call this value WB1. You then obtain a photo of the side and when printing it out ... it IS important to print it ... the wheelbase measures 5 inches. Call this number WB2. This is the proportion you need to scale off the print. Now say you want to know the diameter of the tires on the real car. Call the call the dimension of the tire in your printout T2. The actual dimension of the tire would be T2 x WB1 / WB2.

Another way to say this is, divide the actual wheelbase by the dimension of the wheelbase in the print. This is your proportion. Then, multiply this by the dimension you measure off the print to get the actual dimension of this on the car.

So, with the example I gave our basic proportion is 100 divided by 5 which equals 20. If the rims on the print measured .75 inches, you multiply that by 20 and get 15 inch rims.

So there's the math. Good luck finding reference materiel you can use to do this.

[jeffb]

thanks for all the info. so what it looks like is.i take all my prodigious math skills, and whip out my trusty tape measure and go find me a 1;1 . actually, all this stuff will help...

[Harry P.]

If you want accuracy, the best way to do it is to measure the 1:1.

But don't feel too bad if you don't get it exactly right. The kitmakers themselves are all over the place when it comes to scale accuracy. They're supposedly "professionals" and they can't even get it right sometimes.

[jeffb]

and theres always the correct mesurement, then theres what looks right to the eye. when i did my ranchero, i had a 1;1 in the driveway. i fabbed up the side windows to the correct numbers. it didnt look even remotely right. sometimes ya gotta go with what looks right, not what is right. but try tellin that to the rivet counters......

[Aaronw]

What I've done is take some good straight on side, front and rear view pics. Then I took a part I knew the size of and used it to scale a grid which I layed over the photos.

I was using it for a fairly slab sided body which would be easier than on most cars. It still required a little adjustment to taste but at least got me to a point I could work from.

Edited June 15, 2009 by Aaronw