• March 24, 2024, 8:32 p.m.

    Most people, when they notice that their architectural photographs contain buildings that are apparently not vertical, turn to software to correct the perspective.

    To illustrate this, here is a building taken with a Canon RF16 16mm lens, with no changes other than resizing.

    IMG_7543_b.jpg

    It is an attractive building from the Jugendstil period, but the picture shows it learning unacceptably backwards, with the top apparently narrower than the base. This is because the camera is pointing upwards at an angle (Note that the vertical centre of the photo is at the level of the second balcony, rather than at the height of the photographer -- 6ft from the ground). The reasons for this are that the street is too narrow to allow me to move any further back, and I have no access to the upper floors of the building behind me, which would allow me to level the camera, while still pointing it at the second balcony

    This is what happens when I click on Perspective in DXO PhotoLab 6:

    IMG_7543_b-1.jpg

    The sides are now more or less parallel; but in achieving this the bottoms of the sides of the building have been moved inwards, and the resultant black triangles need to be cropped away, after which we are left with this:

    IMG_7543_b-2.jpg

    The resullt is not very good, because I had to leave a black triangle at the bottom right in order to include the right hand edge of the building. Clearly a wider angle lens is required. This would leave more "spare image" on the edges to be cropped away after "fixing" the perspective. It should, however, be noted that moving pixels around in this way can easily have an effect on the clarity of the photo.


    I had a go with a wider lens, this time a Laowa 12mm, standing in pretty much the same spot. Here is the result out of the camera:

    IMG_7555_b.jpg

    With perspective correction:

    IMG_7555_1-b.jpg

    Cropped:

    IMG_7555_2-b.jpg

    The result is a little more natural, and I might make a few adjustments; but finally I prefer this view, taken at an angle with the 15mm lens:

    IMG_7558_b.jpg


    In sum, a situation in which a lack of space in the street makes a satisfactory photo, with right angles where they should be, pretty impossible by means of software correction.

    This is an extreme case, and a really good photo can probably only be taken from an upper floor of the building on my side of the street. (Even so, it is probably a lost cause because the view of the umbrella awnings would be from above!)

    I used PhotoLab for this demonstration because this is what I have, but other software, like Photoshop, would give the same result.

    There are cameras, like the Leica Q3, that can do the perspective correction in the camera, but they also have to crop the view.

    David

    IMG_7558_b.jpg

    JPG, 1.5 MB, uploaded by davidwien on March 25, 2024.

    IMG_7555_2-b.jpg

    JPG, 1.0 MB, uploaded by davidwien on March 25, 2024.

    IMG_7555_1-b.jpg

    JPG, 407.2 KB, uploaded by davidwien on March 25, 2024.

    IMG_7555_b.jpg

    JPG, 967.5 KB, uploaded by davidwien on March 25, 2024.

    IMG_7543_b-2.jpg

    JPG, 855.9 KB, uploaded by davidwien on March 24, 2024.

    IMG_7543_b-1.jpg

    JPG, 623.5 KB, uploaded by davidwien on March 24, 2024.

    IMG_7543_b.jpg

    JPG, 695.2 KB, uploaded by davidwien on March 24, 2024.

  • Members 1827 posts
    March 25, 2024, 5:04 p.m.

    Yes, I have done a lot of correcting in post. It takes a lot of discipline, luck and a wider lens, to leave enough space around the subject, to avoid strange crops and loss of important objects in the picture.

  • Members 561 posts
    March 25, 2024, 5:32 p.m.

    I notice that in these threads on "correcting perspective" ( a misnomer because they are not correcting perspective, simply changing the position of the centre of perspective), the question of why we like pictures better when the verticals are made vertical is rarely addressed.

    We are much more tolerant of horizontal lines not all being horizontal, except that most people like to see the horizon as horizontal.

  • Members 1827 posts
    March 25, 2024, 5:37 p.m.

    Because our onboard computer, behind our eyes corrects keystoning, and we expect to see vertical building lines represented vertically in a picture.

  • March 25, 2024, 6:25 p.m.

    Not always - looking at @NCV wonderful architectural images, some of those would look more appealing to me with non-vertical verticals :)
    It heavily depends on scene, also on what I have used to see in photographs.

  • Members 322 posts
    March 26, 2024, 7:07 a.m.

    HAND.

  • Members 561 posts
    March 26, 2024, 9:22 a.m.

    So you are saying that our brains correct keystoning when we look at a building, but not when we look at a picture of a building?

    If that is so, why?

  • Members 1827 posts
    March 26, 2024, 12:37 p.m.

    Because we know a picture is a picture, and not an actual building. But pictures and drawings can still play tricks on our vision.

  • Members 878 posts
    March 26, 2024, 1:46 p.m.

    [deleted]

  • Members 1827 posts
    March 26, 2024, 2:50 p.m.

    This occurs with extreme perspective effects, when we use lenses wider than 24mm, and is easy to tweak in post with some minimal correction. It does not apply so much to pictures without dramatic perspective correction.

  • Members 1827 posts
    March 26, 2024, 2:54 p.m.

    They mostly used this trick to render the building taller and more massive to the viewer. The Duomo di Fidenza gets narrower towards the Altar, to make the building seem longer than it really is to those entering via the main door.

    DSC_0383_HDR 3.jpg

    Duomo di Fidenza

    DSC_0383_HDR 3.jpg

    JPG, 1.0 MB, uploaded by NCV on March 26, 2024.