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elainecrossman

Simple perspective correction tool

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a simple perspective correction tool for flat objects on the wall--I used this feature regularly in paint  shop pro before switching to a mac. I photograph paintings, and it is difficult to align oneself perfectly with the work as it hangs on the wall--this little tool, which is similar to a cropping tool, has four corner points which are placed on the corners of the object, and then a simple click aligns the object to a perfect rectangle.

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a simple perspective correction tool for flat objects on the wall--I used this feature regularly in paint  shop pro before switching to a mac. I photograph paintings, and it is difficult to align oneself perfectly with the work as it hangs on the wall--this little tool, which is similar to a cropping tool, has four corner points which are placed on the corners of the object, and then a simple click aligns the object to a perfect rectangle.

Hi,

 

I second that request, it can be a real time saver.

 

However, it's not that simple to do correctly. Just squaring up 4 corner points will distort the original's true dimensions, because there is not enough input about the original projection distortion. Panorama stitching programs can do that correctly, but they need additional input about the focal length (e.g. from the EXIF meta-data) that was used to capture the image. Then, on the uncropped full-size image, it can try to rotate the projected image, and shift it off center (since the optical axis was not perpendicular to the subject plane), move the virtual camera position, and then crop the boundaries.

 

So absolutely doable, not easy to do well, but it would be a very welcome addition. If done properly, it would be another improvement over what some other photo-editors produce.

 

Cheers,

Bart

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If needed corrections are minor there is no need for complicated perspective correction. Simple free transform is enough.

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+1 for simple free transform. Use case: adding labels or logo's on mockup 3D packaging boxes. Hate to go back to that other software for that now that I'm used to using Affinity. Just rotate and skew don't cut it, sorry.

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Hi moonbeetle,

Welcome to Affinity Forums :)

Which program are you using - Designer or Photo?

Affinity Photo does have a Perspective and Mesh Warp Tools and also a Live Perspective Filter. Only Designer is lacking these features.

The issue being discussed here refers to using them in Photo in a way that they can turn objects in perceptive into a flat/frontal view without distorting their true dimensions.

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The tool is little confusing really because its basic feature by using a large scale grid. 

 

A nice additional feature for that would be 4-point correction. 

 

A1) Draw a two lines with dots that should be straight (like painting edges from top left corner to bottom left corner one line, second line from right top corner to bottom right corner) and correct so that all four points create a rectangle.

 

A2) This could of course always be 3-4 line drawing with automatic cropping too. Like draw a line on left that should be straight. Draw a line on right that should be straight, and then draw a line anywhere between them that should be horizontally in level. So basically you do "H" shape where the middle line can be anywhere from top to bottom. So in this case, draw lines on painting left/right sides and then either top or bottom and it is "squeezed". 

 

B) Draw just a two lines that should be parallel without the dots. So you just draw a one two lines regardless their position or length, and then the form is on that one plane squeezed. So if the camera was not just unparallel, but rolled as well, the painting will get twisted but it has straight edges.

 

C) The meshup tool so you can mark a dots in pairs that should be "in matrix". A each dot has a "source" and "destination" where source is locked in place, and source is allowed to be moved more.  It could be more like a panorama tool for stitching in the Hugin panorama tool. (And this could be later used in the Morphing tool for image animation creation if such ever comes, where you mark the source and destination points in two photos). 

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