Three jpg files in illustrator, added boarder to all three in blue, then 3D extrude and bevel. All settings same for three jpgs. Two of the three view with a blue extrude on top and left side, thrid jpg shows grey on top and blue on the side. Can't get all three to match/ Any idea why?
3D Extrude and bevel is not meant to be used on placed images, and not sure how you are adding a stroke to your jpgs as you cannot do that in illustrator.
The 3D extrude will rotate a jpg and usually give a grey extrude. You could just put a blue vector object in back of your jpg , and 3D extrude that instead. You could do another extrude on your image with no extrude to get that into the correct 3D rotation.
On the grey one, you're seeing the grey extrusion of the raster image, because the blue vector path is not aligned exactly to the top of the raster image.
You're going about this all wrong. Start over thusly:
1. Draw a rectangle the same size as the JPEG. Give it a blue Fill and no Stroke.
2. Drag the JPEG into the Symbols palette.
3. Apply the Extrude Effect to the rectangle.
4. In the Extrude & Bevel dialog, click the Map Artwork button and map the Symbol to the front surface.
Boarders go to boarding school.
(I was one at such an institution a long time ago.)
Borders go around the edge of things and are sometimes used for planting flowers in.
(I have drawn countless examples of the former and have some of the latter in my garden.)