Aspect ratios in photography
Standard aspect ratios used in photography, really useful if you want to give your pictures a different crop, while respecting standards.
When you edit a picture, if you want to crop, would be better if you'd use one standard photography aspect ratio, but what does "aspect ratio" means?
In easy words, it's simply the proportion between the width and the heigh of a picture. Working with any photo editing software (in our case Gimp)
is really simple to to fall into the temptation to randomly cut a photo as we like, without considering that there are very precise rules
of format that should be respected.
The standards belong to the photography with films and have been maintained (fortunately) unchanged over the years, even in a world of digital imaging, social networks and "stretched" monitors, in new years there have been a couple of new appearances.
The main purpose of standard formats in photography is to find the best aesthetic relationship between the long and short sides of the photograph, so as to achieve consistent and satisfying images. of the photograph, in order to get consistent and satisfying images. When you go to scale an image, it is useful to remember to use the rule of thirds to get images that are also well-balanced in composition.
Important: For each format, we'll write a "multiplication factor". This data is useful in the resize and refers to the relationship between the long side and the short side of the photo. For example in the format 3/2 the value is 1.5 (3 divided by 2). If your photo height is 2000 pixels its width shoud be 2000x1.5=3000 pixels (or, if its width is 3000 pixels, its height must be 3000/1.5=2000 pixels).
Now that you know the different standard aspect ratios, it would be advisable to use always one of this standards while cropping your photos, and never crop a picture randomly.
Now to the most practical part of this guide: if you want to use one of your photos to create a computer background, we really recommend to discover the native resolution of your screen and use that one; This is different for televisions, where there are more precise standards. To upload photographs to a TV you'll have to use one of the four main formats:
- HD Ready - 1360x768 for small televisions
- Full HD - 1920x1080 for the most of the screens around 32"
- Ultra HD 4K - 4096×2048 for most of the televisions around 40"
- Ultra HDTV 8K - 7680×4320 For huge and expensive new televisons
When printing on photographic paper, always try to maintain a 3/2 ratio. Many cameras allow you to adjust the different sizes from the menu, so choose the most suitable one carefully. Personally, I always shoot in 3/2 and, if I need to change the format, I crop the picture subsequently the photograph. In vertical photographs I always try to leave a little bit of superfluous image in order to reduce it to 3/4. Obviously the standards do not dictate the law, no one prevents you from cutting the as you like, especially in the realization of particular projects. particular projects. As always, however, before breaking the rules, it is better to know them.
Below you will find a list of some standard resolutions in the world of displays, just to give you an idea of the fragmentation:
- Old Low-end smartphones: 240x320 - 320x480
- Low-end smartphones: 480x640
- Mid-range Smartphones: 800x1280 - 1080x1920
- 2k Smartphones (Quad HD): 1440x2560
- 21/9 Smartphones: 1560x720 - 2340x1080 - 1440x3040
- Low-end Tablet: 800x600
- Mid-range Tablet: 1024x768 - 1280x800
- High-end Tablet: 2560x1600 - 4163x3122
- Ipad Retina: 2048×1536
- Standard 4/3 monitors resolutions: 640x480 - 800x600 - 1024x768 - 1280x1024 - 1600x1200 - 2048x1536
- Standard 16/9 monitors resolutions: 854x480 - 1366x768 - 1920x1080 - 2560x1440
- Standard 16/10 monitors resolutions: 1280x800 - 1440x900 - 1680x1050 - 1920x1200
- Standard 21/9 monitors resolutions: 1680×720 - 2560×1080 - 5120×2160 (5K)
- Standard 4K (Ultra HD) monitors resolutions: 3840x2160
- Standard 8k (Ultra UHDTV) monitors resolutions: 7680×4320
- 3 Megapixel 2048x1536
- 5 Megapixel 2560x1920
- 8 Megapixel 3264x2488
- 15 Megapixel 4480x3360
- 18 Megapixel 5184x3456
- 21 Megapixel 5616x3744
- 50 Megapixel 8688x5792
Publication on the internet
With the advent of the social networks, it is important to make a small parenthesis, because the standard resolutions and aspect ratios are changing. For example let's take Instagram: photographers are "forced" to cut the images and redefine them in 5/4 (an out-of-standard format), just to meet the layout requirements dictated by the social network.
Our advice is to work always in the standard format and then change the crop ofthe photos to meet the differet layout requirements. The ultimate goal of a photograph should always be printing, so I think is better to don't be distracted by the fashions of the moment. Let's see how to export a photo for the main social networks:
Export to Facebook
Facebook tends to redefine the images on the long side, leaving the vertical resolution free. In this way we can publish the images with the aspect ratio that we prefer. We have to scale the images to 2048px on the long side for upload in high quality and try to minimize the compression done by the social network.
Export to Instagram
Unfortunately Instagram is quite ruthless with the crop of photographs, so if you are not careful you risk to find out that you miss a slice of the image after the upload. If you want to keep a standard aspect ratio, the only way to overcome this problem is to add bands above and below the photograph or voluntarily cut in the 5/4 size (non-standard). So you have to decide if you want to crop the shot or if you want to add some bands. The recommended export resolutions to avoid further compression are:
- 1080x1080px for square photo 1:1
- 1080×1350px for horizontal photo 5:4
- 1340×1080px for vertical photo 4:5
Printing aspect ratios and minimum resolutions
If you need to print your pictures, respecting the standard aspect ratios is even more important. If you want to avoid unwanted crops or unprinted bands, you have to choose wisely the crop of your photos. In the choice of photographic papers, it is possible to find all the standard sizes plus some old formats that are no longer in use, such as 4/5 or 5/7.
Very important in printing is also the resolution of the shots that will be used, because a larger print size needs higher resolutions in megapixels in order to have the maximum sharpness. Below we will list the standard formats and the minimum recommended resolution for printing. Obviously the minimum resolution is not the recommended one, which should be at least double, although much depends on the resolution of the machine that will be used to print the photos.
- 3/2 Prints: 10x15cm (4x6 inches), minimum resolution 800x1200 pixel
- 3/2 Prints: 20x30cm (8x12 inches), minimum resolution 1600x2400 pixel
- 3/2 Prints: 30x45cm, minimum resolution 2400x3600 pixel
- 3/2 Prints: 40x60cm, minimum resolution 3200x4800 pixel
- 3/2 Prints: 76x114cm, minimum resolution 6000x9000 pixel
- 4/3 Prints: 9x13cm, minimum resolution 700x1200 pixel
- 4/3 Prints: 15x21cm, minimum resolution 1200x1600 pixel
- 4/3 Prints: 30x40cm, minimum resolution 2400x3200 pixel
- 4/3 Prints: 40x53cm, minimum resolution 3200x4200 pixel
- 4/3 Prints: 76x101cm, minimum resolution 6000x8000 pixel
- Squared prints: 13x13cm, minimum resolution 1000x1000 pixel
- Squared prints: 20x20cm, minimum resolution 1600x1600 pixel
- Squared prints: 30x30cm, minimum resolution 2400x2400 pixel
- Panoramic prints 16/9: 30x53cm, minimum resolution 2400x4200 pixel
- Panoramic prints 16/9: 50x90cm, minimum resolution 4000x7000 pixel
- Other prints: ID Photo, 3.5x4.5cm, minimum resolution 280x360 pixel
- Other prints: Small mousepad, 20x30cm, minimum resolution 1600x2400 pixel
But when can we "deviate"?
Now that we have found out what all the photographic standards for photo format are, we need to understand when it is possible to break the rules described above. So what should we do if we are forced to work outside the standard? There are in fact situations where it is not possible to use any of the above solutions. Let's think of a poster that must be cut to fit a window, or adapt to a window, or all the situations where we have to work on non-photographic spaces. In this case the most important thing important thing is to use the rule of thirds to try to compose a photograph that is correct from the point of view of composition and to use the tips described above, trying to fit the photographic format closest to the one being used.
If you liked this tutorial here you can find all the other tutorials we wrote about photography, or you can go there to take a look to our tutorials for post production with Gimp. If you liked our work, you could consider to ❤support us: by clicking here you can see how.