The Image Scaling feature in Postbox resizes large inline images with just a few clicks. Here's how it works:
When you embed an image into the message body, a scaling bar will appear to display the message size and image resizing options.
When you select the image to be resized, if the image width or height (whichever is larger) exceeds 320px, 640px, or 1280px, resize icons will appear that will allow you to size the image to those max dimensions.
Select an image to be resized, then click on a resize icon to scale the image down. Deselect the resize icon to revert the image to its original size and resolution.
Tip: If you scale an image down, but then wish to size it back up, we recommend reloading the image by deselecting the resize icon first, then selecting the new size to minimize loss of resolution.
Note that the resize options that display are dependent on the initial image size. For example, if the image width or height is under 1280px, then only the 320px and 640px image resize options will appear. If the image width or height exceeds 1280px, then all image resize options will appear.
If you embed multiple images in a message, each image can be independently resized, providing you with more fine-grained control over your message content.
Message Size Indicator
The message size indicator will display the total message size, including text and images.
Some ISPs have size limits for messages sent through their servers. For example, Gmail places a 25MB limit on email messages.
You can set Postbox to warn you if you exceed this threshold in Preferences / Composition / Advanced. Simply set the maximum threshold, and you will be warned when your message exceeds this threshold.
To determine the max send thresholds for your email account, please contact your ISP or IT administrator for details.