Correcting Capture One’s Keystone Distortion: How to Solve Perspective Problems in Architecture Plans


Quite often it’s the subtle touches that separate professional photography from amateur shots, and one of the key examples is perspective correction – or “keystone” correction in Capture One. The human eye is very sensitive, and even a small degree of tilt, tilt, or convergence can spoil shots of buildings and landmarks.

Whenever we shoot out of shot from an object, with standard lenses, we introduce perspective distortion. This is the effect where the part of the subject furthest from us becomes smaller in the scene.

While this can sometimes be useful for giving an impression of distance or height, when you want a sharper front shot you really only have two options: either use a dedicated tilt / shift lens or correct it. in post-processing.

For those who don’t have such a specific goal, Capture One’s keystone tool can fix things with just a few clicks.

1. Where to find the keystone tool
the keystone tool can be found in the top menu bar, but keep in mind that there are three versions of the tool (vertical lines only, horizontal lines only, or 4-way keystone correction) which can be found by holding down the button. the mouse pressed on the tool itself.

(Image credit: Paul Reiffer)

2. Numerical values
It’s also worth remembering that the tool is actually just a graphical interpretation of the numbers in the Keystone tab on your side tool panel. As you move the anchor points, the tool interprets them as numeric values ​​that are passed to this panel.

(Image credit: Paul Reiffer)

3. Visual adjustment
While you can use the sliders on the Tool Panel to make adjustments, it’s often easier to use the anchor points and their intermediate guides to let Capture One do the calculations for you.

(Image credit: Paul Reiffer)

4. Aspect ratios
The goal is to place the anchor points on a line that SHOULD be straight but is not (it is not already correct). In the case of vertical only, this means a line which must be straight from top to bottom. In the case of a horizontal trapezoidal adjustment, these are lines which must be perfectly flat and level.

Dragging these points to their respective areas will show you (along with the connecting lines) what else between these points will be leveled, and when you’re happy click Apply.

If the result now looks too “squashed”, consider using the “Aspect” slider to stretch or flatten the image to your liking.

(Image credit: Paul Reiffer)

5. Check the crop
You will be lose part of your larger image due to cropping, due to correction – so it’s worth checking the uncropped version to see what got pulled out of the frame. Also keep in mind that the default ‘amount’ of correction is 80 – not quite practical for the architecture which needs to be 100% straight, so it’s worth resetting it to 100 once you have defined your anchor points.

(Image credit: Paul Reiffer)

6. Four-way adjustment
The four-way tool works exactly the same as the horizontal or vertical version, only it allows a complete transformation of an object in one go.

(Image credit: Paul Reiffer)

As before, just select 4 points which should all be linked in a right rectangle and hit apply.

(Image credit: Paul Reiffer)

Getting things right in-camera will always be necessary when it comes to architectural photography – and for those times, a tilt / shift lens can be the winning tool.

But for those who need to make minor adjustments infrequently, or if you don’t take enough of those footage to justify the investment in a dedicated lens, the Keystone Tool is here to help with just a few clicks.


About Capture One

Capture One is an all-in-one, non-destructive image cataloging, raw processing, and editing tool, and its closest rival is Adobe Lightroom Classic. In addition to the regular “all camera” edition, there are cheaper Nikon, Sony and Fujifilm-specific editions. Capture One is regularly featured in our guide to the best photo editing software, thanks to its high-quality raw processing, in-depth color controls, and layer- and mask-based editing.

• Our links below show the prices for the subscription versions, but you can click on them to browse all editions and packs. Capture One is also available for a one-time payment.

Read more:

• The best tilt and shift lenses
• The best tripods
• Best photo editing laptops
• Best monitors for photo editing
• Best portable hard drives


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