Why do digital cameras not support PNG?
Above is a PNG image, as in Portable Network Graphics image, captured from the movie Blade Runner. PNG is a better format than JPG concerning resolution in the respect there is no perceptible digital noise...
...so why is it that digital cameras don't support it more?
PNG isn't a new format, as it was approved for use in 1996. However, it didn't get certified as an ISO standard until 2004. And yeah, that was 10 years ago at the time I write this, but there are still a few things about PNG that make it suck where digital cameras are concerned.
To note, some digital cameras do support PNG, but not many. Usually, PNG support is only found on super-expensive cameras.
These are the reasons why you almost never see a PNG file format option on digital cameras:
- To the best of my knowledge, PNG does not have a standardized way to store EXIF data, which is really important to photographers.
- It takes a digital camera a lot longer to render a PNG because much more color data is included in the finalized file.
- PNG was never designed to be printed (hence "network graphic").
When you want an image from a camera that contains as much data as possible, you either output the file as RAW or TIFF.
Anything output as RAW is in the native format of the camera itself; this is why you need special software specific to the camera manufacturer just to read RAW output image files.
TIFF (Tagged Image File Format) was designed as a publishing format. It's freakin' huge on output, but contains all the data needed and is really flexible in what you can do with it. It can also contain a lot of meta data that's very useful to photographers.
On screen, PNG looks better. On a print, it doesn't. And while PNG isn't as large as TIFF, the lack of meta data makes it fairly useless.
If your camera had the ability to output PNG files, you would wait twice as long for each image to store to memory, it would kill your battery twice as fast, and on upload to any photo-specific site on the internet, any meta data in it would be proprietary and not be read properly - if at all.
JPG is the best possible image format for a digital camera to use. It can store a ton of meta data, be compressed easily and JPG files render quickly. Maybe JPG is a bit "noisy" at times, but there really is nothing better.