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View Full Version : Taking orthographic photographs



baeksoo
02-16-2005, 08:04 AM
I'm trying to see if I can take some orthographic shots of a small object (shoebox sized) for use as reference images....so far a bit unsuccessfully.

Is this possible to do without expensive studio equipment and/or extensive photography knowledge? I'm just working with a desk, a point-and-click digital camera, and a mini tripod :)

Skonk
02-16-2005, 08:12 AM
Stand as far away from it as you can and use as much zoom as you can, that should remove some of the perspective.

Mylenium
02-16-2005, 11:29 PM
I'm trying to see if I can take some orthographic shots of a small object (shoebox sized) for use as reference images....so far a bit unsuccessfully.

Is this possible to do without expensive studio equipment and/or extensive photography knowledge? I'm just working with a desk, a point-and-click digital camera, and a mini tripod :)

Ahem, in the real world there ain't such a thing as true orthographic projection - it goes against all rules of physics. If ever, those effects are created using extensive combinations of lenses or digital manipulation later on. I guess with your "cheap" camera you are out of luck anyway no matter how far you move away and zoom - those tiny lenses have a terrible distortion due to ther strong curvature and short focal lengths.

Mylenium

private
02-17-2005, 04:43 AM
Take a picture and go. It's not going to be 100%. You're going to have to finesse some parts eventually. Use the reference as a guide and go from there.

cresshead
02-17-2005, 06:16 AM
depending on the size of the object you could scan it in....
some scanners are 3D scanners as in they have a good depth of field and not just the surface on the glass scan area...

also you can correct a distorted photo due to lens by uv editing it's texture once in lw.

it depend on how accrate you need it....
also always measure your object and create a proxy in modeler to work from as a guide.

starbase1
02-17-2005, 06:34 AM
Although absolute ortho is not going to happen, there are several ways around it.

Much depends on what you want to do with the image afterwards, but there are a few useful cheats.

As said, get as far away as possible and use as much zoom as you can for a start.

As its a small object, try and find a properly square object to sit it in - something like a partial box would be very good. A wireframe cube would be even better. You can then use the edges of this as a guide - by fixing the image afterwards to remove the vanishing points for the box, you would effectively correct to an ortho view. Filters in photoshop will be a great help here - they are intended for things like removing converging verticals on big building shots. Try searching for 'fix converging verticals' and you will probably find something useful.

If you ever need a wider angle shot, (for something bigger for example) then most panoramic stitching software will let you adjust or remap images, or give a choice of projections - this will only really work well near the centre of the big image, but it will help.

Nick