Tilt Angle Calculator
Tell us your lens and how high it sits above the surface you want sharp, and we work out how many degrees to tilt, updated as you type. It also tells you whether your lens can physically reach that angle, and how thick the sharp zone ends up at your subject. Everything runs in your browser, nothing uploaded.
Side view
Tilt against distance
Backing away from the surface lowers the tilt you need. Where the curve crosses the limit line is the closest your lens can work.
Learn more: how much tilt a scene needs
How the hinge rule sets the angle
A tilted lens does not simply lean the plane of sharp focus over. It pins that plane to a fixed line in space, the hinge line, and the plane swings about that line as you refocus. The hinge line sits a distance J from the lens, measured in the plane through the lens that runs parallel to the sensor, where J = f / sin(tilt).
Turned around, that gives the only figure you need. To land the hinge line in your subject plane, tilt by arcsin(f / J). A 50 mm lens 0.8 m above a tabletop needs arcsin(50 / 800) = 3.58 degrees. A 90 mm lens at the same height needs 6.46 degrees, so focal length drives the angle as hard as distance does.
If the camera is not looking straight along the surface, the hinge line moves further out: J = h / cos(a), with h the perpendicular distance from lens to surface and a the angle the camera is pointed away from the surface. Tipping down 30 degrees from 0.8 m stretches J to 0.92 m and drops the required tilt to 3.10 degrees. The arcsine in lib/tilt.js is all of this app's core maths.
Once the angle is set, focusing stops being fiddly. Every point on the surface shares the hinge line with the plane of sharp focus, so bringing any single point on the surface into focus swings the whole plane into place with it.
When the lens cannot reach the angle
Rearranging for the lens's own limit gives the closest it can work: J = f / sin(maximum tilt). Canon publishes 6.5 degrees of tilt for the TS-E 17mm f/4L and 10 degrees for the TS-E 90mm f/2.8L Macro, and Nikon lists 8.5 degrees for the PC-E Micro Nikkor 45mm f/2.8D ED.
Feed those in and the limits turn concrete. The 90 mm macro cannot put its hinge line nearer than 90 / sin(10 degrees) = 518 mm, so it has to sit roughly 0.52 m above a tabletop before any tilt setting works. The 17 mm gets down to 150 mm. A 4x5 view camera with 20 degrees of front tilt on a 150 mm lens reaches 439 mm.
There are two ways out of running short. Back away until J is large enough, or fit a shorter lens: at a fixed J the longest focal length that stays inside the limit is J multiplied by sin(maximum tilt), which is the second figure this page reports.
The sharp zone is a wedge, not a slab
Both limits of acceptable focus pass through the same hinge line as the plane of sharp focus itself, so what you can call sharp is a wedge with its point at the hinge line. Near the hinge line it is almost nothing. Far out it is generous.
As a slope, the half width of that wedge is (N x c / f) x (1 / tan(tilt) - s), where N is the f-number, c the acceptable blur circle and s the slope of the surface. This page takes c as the frame diagonal divided by 1500, which is 0.029 mm on full frame.
Back to the 50 mm example at f/8 on full frame: the half slope comes out at 0.0737. Two metres along the surface from the hinge line that is a zone 29.5 cm thick, split evenly above and below the surface. Half a metre out it is 7.4 cm. That is why correct tilt does not remove the need to stop down, since anything with height standing on the surface pokes out of a thin wedge near the hinge line.
Wikipedia's treatment of the Scheimpflug principle notes that this thickness is shared evenly either side of the plane when measured on a plane parallel to the sensor, while the two angles are not equal. That is why the figure here is one opening angle for the whole wedge rather than a near and far pair.
FAQ
How much tilt do I need for a tabletop shot?
Measure how high the lens sits above the table, not how far away the subject is along it, and take the arcsine of the focal length divided by that height. A 50 mm lens 0.8 m above the table needs arcsin(50 / 800) = 3.58 degrees. A 90 mm lens at the same height needs 6.46 degrees, because the required angle scales with focal length.
Why does my tilt-shift lens run out of tilt?
Because the angle the hinge rule asks for grows as you get closer to the plane and as the lens gets longer, while the lens itself stops at a fixed figure. A TS-E 90mm f/2.8L Macro stopping at 10 degrees cannot place its hinge line nearer than 90 / sin(10 degrees) = 518 mm, so it has to sit about 0.52 m above a tabletop before any tilt setting works. Backing away or fitting a shorter lens are the two ways out.
Do I still need to stop down once the tilt is right?
Yes, because correct tilt only guarantees the plane itself, and anything with height standing on that plane sits inside a wedge that narrows to nothing at the hinge line. With a 50 mm lens at f/8 on full frame and the hinge line 0.8 m away, the zone is 7.4 cm thick half a metre out along the plane and 29.5 cm thick at two metres. Stopping down widens the wedge at every distance.