Help making a acurately sized background
SloYerRoll
Registered Users Posts: 2,788 Major grins
When making a background for shooting glass, I've gotten the background size close to acceptable margins for filling the frame and not bleeding over too much. But it was definately trial and error.
Question:
Is there a way I can figure out what size I should make a backdrop through math instead of guessing. This way I can also make it out of coroplast and have it for good.
Shooting w/ a D200 and I have a few options for glass.
Cheers,
-Jon
Question:
Is there a way I can figure out what size I should make a backdrop through math instead of guessing. This way I can also make it out of coroplast and have it for good.
Shooting w/ a D200 and I have a few options for glass.
Cheers,
-Jon
0
Comments
Jon,
While there are mathematical and geometrical and trigonometric calculations you could perform, the task can be performed much more easily.
Set up the shot as required. Include a yardstick or tape-measure in the shot where you wish to put the background. Assuming a "landscape" camera orientation, position the measuring device horizontally and along the longest edge of the frame. Once you have that measurement you have the longest edge. To determine the shorter side just multiply by ".66". That should get you very close for a background thet is set close to parallel with respect to the film plane.
If you need to reset the shot it will change the geometry of the background (most likely), so you might need to determine the worst-case scenario to fit all lesser combinations.
A string with markings every inch might be easier to place and hold in the shot, depending on methodology.
Moderator of the Cameras and Accessories forums
Thanks for the knowledge.
Cheers,
-Jon
I keep thinking one us ain't real quick in the brain area, and I'ma hoping it's not me.
If you need a background why does it need to be a specific size? Why not make it large enough to accommodate a variety of subject sizes. Up to your space or anticipated maximum size of course.
Example: 12 high vase. Black background: 4' X 8' foam core. Yes much larger than needed, but good for larger objects, as well as smaller ones.
????
Sam
The only requirement for shooting glass in a "White Filed" is that the background can't extend past the frame of the shot. This is due to reflections in the family of angles that will show up in the glass.
I suppose you could just make one big one then when your shooting something very small like a shot glass. You could just crop so you essentially are shooting w/ a 2.0MP camera. I don't care for that idea too much though. I'll probably have three generic sizes now that I KNOW how to make the correct size. Then make custom ones if needed. But I don't see the need if I have three sizes.
In addition, you have to consider orientation. If I want to be level w/ a very small object. I can't use your large backdrop. It's impossible due to perspective.
Does that answer your question?