Constrain a brush stroke along a pre-defined path

[mrd5477]

Can anyone tell me if there is a way (using Photoshop) to constrain a brush stroke along a pre-defined path?

I am trying to airbrush a car to look like the example I have attached. As you can see towards the bottom edge of the door between the wheels and up over the rear wheel arch there is a line of white.

I'd like to be able to define this path so that I can repeatedly brush along it to build up the amount of reflection. This would allow me to change the size & opacity of brush to give a more blended feel whilst consistently painting the same area.

When I try to do this freehand I get a bit wobbly and rarely repeat the brush stroke exactly as before. I guess that's the trouble with using a mouse! Fingers crossed because I've been a very good boy this year that Mr Claus will delight me with a Graphics Tablet!!

If anyone could offer any help with this or know of any tutorials that might help me then I'd be very grateful.

Thanks,
Martin

[Swampy]

Originally Posted by mrd5477

Can anyone tell me if there is a way (using Photoshop) to constrain a brush stroke along a pre-defined path?

You can define the path with the pen tool, set the brush color size, opacity etc. then stroke the workpath. As far as further manipulation of that line, I've never played with it.

The line is treated as a vector shape, but you may be able to dodge/burn it.

[CJ Swartz]

This isn't exactly what you want, but have you tried using the "Shift" key to constrain Photoshop's Paintbrush to a perfectly flat horizontal line from one point to another point. You click on the Shift key before you click on your brush, then click on your brush at the starting point and then move it to the end point (still holding the Shift key down) and click your brush on the end point. It's not exactly what you need, but it might help until you get your Christmas wish tablet.

[Cassidy]

Not sure if I am following you correctly, but using the magic wand you can select an area which will prevent you working outside of it, to extend the area hold down shift and click again in the extended area

[Syd]

I am also not sure if I am understanding you correctly, but if I do, it is rather simple. Define your path and then, in the paths pallette under options you click 'stroke path'. You can stroke the path any number of times you want with varying opacities, sizes, shapes, simulate pen pressure, jitter, etc. There is no limit to how many times you can stroke a path. There is also a 'stroke path' icon at the bottom of the paths pallette. Just make sure you have already selected your brush, size, opacity, etc before you stroke, otherwise you might be stroking it with the pencil.

Syd

[CathyH]

Have you tried to used the paths pallet?
Go to the paths pallet and make a new layer. Draw a path you want to stroke with the dots. Then select the brush tools and in the brush presets expand the spacing until you see dots.