Including images in an email message can be tricky. When sending email to a mailing list with hundreds or thousands of recipients, you need to do it properly.
Here is the preferred method.
When you submit messages via email however there can be an issue: some email clients (Outlook, Thunderbird, etc.) allow for images to be "embedded". In other words, the pictures you insert into your message are copied from files on YOUR computer and sent along as attachments so they can be quickly viewed by the recipients. You yourself don't attach the files; your email client does it "helpfully" for you.
If you embed images in this way, the actual email message you send can become HUGE: 500k, 1MB or more in size, especially if you don't resize your images before using them. Now, even a 1MB message isn't really "big", and not a problem for most recipients in the USA, and not much of an issue when you're sending 1-to-1 emails.
But messages that big can be a limitation for readers on a slow connection such as dialup or satellite modem. It may also negatively affect recipients who read the message on their smartphone but have a limited data plan. So depending on your audience, you should attempt to reduce the message size.
This embedding of images only occurs when the message is created in your email client and then emailed to your list's control- address. A better way to add pictures to a newsletter is to first upload all images to a hosting service (e.g. dropbox, imgur, picasa, et al) and then include only LINKS to the needed images. This is the way most newsletters are created.
There are some advantages to embedding photos:
- Doesn't require the recipient to "enable images" in order to see them.
- Doesn't require the recipient to have an internet connection when reading the message in order to see the images (but every recipient must instead download all images as part of the message).
- When preparing the message, embedding can be easier than uploading images, then finding and using proper links from the hosting service.
But the disadvantages of embedding photos outweigh the advantages:
- Message size can be very large.
- Delivery time to your list can be quite a bit longer, since each message sent is much bigger.
- Since the recipient does not need to "enable images", any HTML images you DO use won't be seen - including the tracking image used for open-rate tracking. If recipients aren't required to enable such images, opens can't be tracked. Not a big deal unless you're trying to use open-rate tracking...
- If recipients reply, their replies to you will all be big since they will typically include your original message.
- Images can only be embedded when posting by email, if your email client supports it. When you prepare and schedule a message using our web admin, images can only be included as links.
This is a pretty technical issue, but it explains why most email newsletter services require messages to be prepared only online. That way they can require any/all images to be hosted. Because we allow posting by email, this is a potential issue for those who use that feature.