You should probably test your emails in IBM Notes 10...
Anyone a fan of IBM (formerly Lotus) Notes? There's got to be a few of you out there...
In testing the latest version, IBM Notes 10, our team uncovered a potentially significant bug. Unlike previous versions of Notes, the latest has problems loading and displaying certain JPEG images.
While we're all familiar with JPEGs, you may not know that you can encode them for different colorspaces. The most common is RGB or sRGB, which is the default for most applications like Photoshop when exporting JPEGs. However, images originally intended for print applications can use any of a number of CMYK encodings.
In IBM Notes 10, CMYK-encoded JPEGs will not currently load and display for users. RGB-encoded JPEGs will, though. Here's a screenshot from some testing:
It's worth testing your emails to make sure they are displaying properly in IBM Notes 10. While I don't expect a lot of folks to be using CMYK-encoded images in their emails, I know from my previous life at an agency that it's not outside the realm of possibility. Clients send over some weird creative and assets, so I've seen stranger things happen.
As a backup, it's always worth using ALT text where appropriate, which can be displayed in IBM Notes 10.
IBM Notes 10 is available for testing in Litmus, so have at it and comment on any other issues in this thread. Cheers!