When uploading images to the platform, it is important to keep in mind the size of these images, to ensure that even those on less than optimal internet connections are able to enjoy the platform with minimal lag. Generally speaking, most images can be compressed down to tens of kilobytes in size without major loss in quality, and even large detailed images can be compressed down to hundreds of kilobytes.
There are a few things you can do when producing images to ensure that the final file size isn't too big.
It's always handy to know how large the image will actually be displayed on the platform, so you can make the image only as large as it needs to be. For example, when you view the dashboard on a desktop computer, the image widgets on the left-hand side are 810 pixels wide, and image widgets on the right-hand side are 400 pixels wide.
This means that if you have an image on the left-hand side of the dashboard that is 1620 pixels wide by 440 pixels tall, it will appear the same on the dashboard as if you had saved the image as 810 pixels wide by 220 pixels tall. The only difference being that the 1620 pixel by 440 pixel image will be much larger in file size!
When you're saving your image, the software might give you a dizzying array of file types to choose from. If possible, it is almost always beneficial to choose JPEG as the file type. This is because choosing JPEG will use clever algorithms to efficiently compress the size of the image while maintaining the quality as much as possible.
Tip: Avoid using PNG files, as they are uncompressed and can result in very large files, this will also cause unnecessary delays when loading images on a Dashboard. JPEG files are a much more appropriate file type for dashboard images.
Some of the more sophisticated image editing software will let you choose the quality of the JPEG when you publish it. This gives you the opportunity to adjust the amount of compression while giving you a preview of how it will look, and what the resulting file size will be. Ultimately it is up to you how compressed you wish the image to be, but keep in mind that it would be best to keep it in the range of tens or hundreds of kilobytes.