You know how buildings lean into the center of your image when you shoot with the camera pointing up? This is known as “converging verticals” or the “keystone effect”. It’s a type of image distortion that is caused by the angle of your camera’s sensor relative to your subject. Sometimes, it’s no big deal. But in architectural images or cityscapes, where there are obvious lines that should be straight/parallel, straightening these lines can take your image to a whole new level. Fortunately, it’s very easy to fix this issue, and I’ll show you how in the video below. Additionally, I’ve posted a description of other techniques you can use to prevent or correct distorted vertical lines to get beautifully straight images.
And these techniques aren’t just useful for buildings. All images show converging verticals when you point the camera up, you may have just not noticed. You might be surprised how much your images improve when you try correcting the perspective.
Straightening in camera
It’s great that we can fix converging verticals in post, but there are good reasons to get it right in the camera. Any time you stretch pixels, you are loosing some quality as well as cropping out part of the image. There are several strategies you can use to get things right in camera:
- Shoot with the camera’s sensor plane parallel to the surface in question. For converging verticals, this means shooting with the camera perfectly level. For converging horizontals, this means shooting with the lens pointed directly at the primary face of the subject. This may mean using a different crop/composition, or shooting from a different location. One way to achieve this, or at least get closer to level, is to step further back from your subject and use a longer lens. This will change the relative size of foreground/background elements, so be careful not to lose the intimacy and mood of the shoot simply to get a technically correct vertical line.
- Shoot with a “tilt-shift” lens. I use all of Nikon’s “PC-E” lenses and love them, especially the 24 and 45mm. Canon users are lucky, as Canon also offers a 17mm tilt-shift lens (I really wish Nikon had one). These lenses are expensive and manual-focus only, but they are often the best or only way to get straight lines in the camera. These lenses have the added benefit of being extremely sharp in the corners (unless you have to shift too far), which is often a nice plus. To use one, level your camera, and then shift the lens up to get the framing you want for your subject. As long as your camera is level, the vertical lines will be perfectly straight.
- Of course, another strategy is simply to enhance the effect. Sometimes this can make an image more dramatic. Or, if some degree of slant is inevitable, it may be better to make it look deliberate than to leave it on the fuzzy edge of straight and slanted.
Other options to straighten with post-processing
The technique I show in the video above is my go-to technique for significant corrections, but there are some other great options.
- Lens corrections tool in Lightroom / Photoshop. I use this to some degree on nearly all my images. For simple images, this may be all I need. For more complex images, I may use this to get a better starting point before using the Photoshop techniques I showed above. Within lens corrections, I check “enable profile corrections” on many images to get rid of lens distortion. Then I use automatic vertical or manual vertical transformation tools to deal with the converging verticals. See this video from the amazing Julieanne Kost for a demo of how to use the lens corrections tool.
- Adaptive Wide Angle in Photoshop (found under the Filter menu). This is a great tool for both images shot with wide angle lenses as well as panoramas that were stitched in Photoshop. It allows a great degree of custom control. It’s much trickier to use than the techniques I show above, but can be a good solution for some complex situations (especially where there is lens distortion on top of converging verticals).
- Warp tool in Photoshop (see Edit/Transform/Warp). I like using this approach when I want to correct something in the middle of the image, without cropping out material from the edges.
Photoshop is the #1 professional image editing program in the world for a reason, it’s incredibly powerful. But that power has a downside, it can also be maddeningly complex. It has over 25 years of features designed to meet the needs of professionals, hobbyists, photographers, web designers, graphic designers, videographers, and more. I’m an Adobe Certified Expert in Photoshop and I don’t even know what many of the options do! But Adobe gets it, and they’ve built some awesome tools to let you customize Photoshop for your needs. One of my favorites is the custom menu editor. This little known tool lets you color-code the menu items you use most and hide the items you never need. And even better, you can save your settings to import on other copies of Photoshop.
I went crazy on an 8-hour flight home from London and made a comprehensive custom menu specifically for photographers, and it’s available for free to all my subscribers (current subscribers will receive an email with a link within the next day). My system for organizing the menus is:
- The most important or frequently-used options are green.
- Other commonly-used options are yellow.
- Less important options get left in the default gray.
- Photoshop settings are blue.
- Items that are rarely or never used for photography are hidden (this includes old filters that don’t support modern high res / 16-bit images, redundant options more commonly accessed elsewhere, press printing options, 3D modeling, tools specific to graphic design, etc). This gets rid of a lot of clutter. In the image below, you can see that my “Layer” menu is roughly 1/3rd shorter than the full default menu. Even though these options are hidden, you can still easily reveal them just by clicking “show all menu items” at the bottom of the menu (I set them up so that the hidden items show in red when displayed.)
To install my custom menu:
- Download the custom menu file (sign up for my free newsletter to get the download link, or check the bottom of the latest newsletter if you’re already a subscriber).
- Just double-click the MNU file (Greg Benz Photoshop Menus.mnu). For most users, this should be all you need to do.
- If you have multiple versions of Photoshop installed, right-click the MNU file to choose which version of Photoshop should open and install the menu.
- If you have any problems with the approach above, you can also take a slightly more complicated approach. Click Edit/Presets/Export/Import Presets. Then click “select import folder” at the bottom-left of the window to point to the folder where you put the MNU file. The file will appear in the list box on the left: just click on it, then click the > arrow to move it to the import box, and then click “import presets” on the bottom right. Once you’ve done this, you still need to activate the imported menu. Click Edit/Menus, then change the “set” dropdown to the custom menu.
- (Note that if you want to remove it, just change the “set” option back to the default or use the trashcan icon to delete it.)
If you prefer to create your own custom menu from scratch or to modify what I’ve done, just follow these steps:
- Click Edit / Menus to open the custom menu editor.
- Make sure “menu for” is set to application menus. (Set it to panel menus if you want to tweak the fly-out menus in the panels. I have also customized these in my custom menus. Unfortunately, you cannot customize the options you see when you right-click in a panel, just the options that show up when you click the three little bars at the top-right of the panel.)
- Click the triangle in front of File, Edit, Image, etc. This will show all of the menu items. Sub-menu items are indented.
- Click on the color options to change the color for each item.
- Click on the visibility (eyeball icon) to show or hide each item. (Be sure to set color before making an item invisible).
- When you are done, click save (first icon with a down arrow) or save as (second icon, by the trash can).
- If you want to switch from one custom menu setup to another, click the “set” dropdown.
- To delete a custom menu, select it under “set” and then click the trashcan icon.
My friend Mark picked me up from the airport in Amsterdam and we drove straight to the ING House to shoot sunset. It was a precision operation, one wrong move – flight, luggage, traffic – and the whole operation would have been blown for the night. But we made it just in time. We walked briskly from the car to the building and immediately started shooting. I love it when a plan comes together. Amsterdammers (I just made that up) like to refer to this building as “The Shoe”. Having seen it from above when we passed by it on the freeway, I can see why people say that (you can’t really see the legs, and the back part looks much more prominent like the whole where you put your foot into a shoe). But having seen it from down low, I would propose to rename it robo-pup. It looks like the sci-fi love child of a chihuahua and a spider. Just add in some yippy barking sound, it’d be “cute”. I hope the architect isn’t reading this – I do like the building, really.
I’m still in awe of how green the glacial lakes of New Zealand can get! And of “lenticular clouds”. I’d never even heard of these crazy round clouds until I went to New Zealand, and then I saw them for days on end. Apparently, some people think they explain many UFO sightings… but we all know little green men like big green lakes.
This is the Jin Mao Tower in Shanghai, China. I took this photo in 2007. When I went back in 2014, I took a photo looking down from the Shanghai World Financial Center (the one under construction in the background), and looked up at the much taller Shanghai Tower being built. I’m starting to think the Chinese should install zip lines between all these super towers, it’d be much faster than having to go down and up so much. Just saying.