I have a serious pet peeve, and it’s one that ruins the experience for everyone involved: bloated, massive, unoptimised image files.

Recently, a client approached me in a panic. They had hired someone to build a course for them in Evolve, but when they handed over the final export, the client was completely unable to upload it back into their own Evolve instance. The file was just too big.

When I opened up the project files to investigate, my jaw dropped.

The entire course was nearly 600MB. For context, a course of this length, with standard audio and images, should have been around 60MB total. So, where was all that bloat coming from?

I looked at the image assets. Some of the individual photos were 18MB each.

18MB for a single image in a web-based course. That is insane.

How I Fixed the 600MB Disaster

So, how did I salvage this mess for the client? I had to go under the hood.

I unzipped the exported course file and dug straight into the asset folders. When I looked at the file info, the problem was obvious: the images had been exported at 300dpi. This is a setting meant for high-quality print brochures, not digital screens!

Using nothing but the standard “Preview” app on my Mac, I manually resized every single bloated image to the correct pixel dimensions. Once I resized and compressed that 18MB image, it dropped to 180KB.

The crucial trick here? I didn’t change a single file name. Because the naming structure remained identical to the original export, I was able to re-zip the entire package perfectly. Once re-zipped, the newly optimised file was uploaded back into Evolve without a single error, and the client was thrilled.

But it never should have come to that.

The Digital Creator’s Responsibility

Every digital creator has a fundamental responsibility to ensure their assets are optimised. It is not just about making sure a file is small enough to upload into an authoring tool. It is about the end-user.

When you upload large images, you force your learners to download them. Not only does this cause your course to load painfully slowly (which kills engagement before the learning even begins), but it needlessly burns through your users’ internet bandwidth. If a learner is taking your “App” style course on their mobile data, an 18MB image is completely unacceptable.

My Exact Process for Optimising Images

You don’t need to be a professional photographer to get this right. You just need a solid, repeatable workflow. Here is the exact process I use to keep my courses lean, fast, and looking beautiful.

1. Nail the Pixel Dimensions (Ignore Print DPI) Many people think they need to save images at 300dpi for them to look “high quality.” Here is an industry secret: web browsers and authoring tools ignore DPI. Screens only care about pixel dimensions. Exporting at 300dpi just massively inflates your pixel count. A 72dpi setting is sufficient for digital exports.

I make sure my images are cropped to the exact pixels needed for the Evolve component:

• Hero Image: 1440 x 1920
• Full Image: 1024 x 400 (or whatever the specific block requires)
• Small Image: 512 x 400

The Golden Rule: I tend to double the pixel dimensions before saving. This accommodates high-resolution Retina screens, ensuring the image looks crisp and sharp on modern devices without blowing out the file size.

2. Choose the Right File Format Not all image formats are created equal. Choosing the right one makes a massive difference:

• JPEG: This is your workhorse. If the image is a standard photograph and has no transparent background, use a JPEG.
• PNG: Only use PNGs if your graphic requires a transparent background (like a cutout character or a logo). PNGs are heavier than JPEGs, so use them sparingly.
• WebP: If I am uploading an image directly onto the web (like a WordPress site) and the platform supports it, I always use WebP. It provides incredible quality at a fraction of the file size of a JPEG or PNG.

3. Crunch the File Size Once my image is the right dimension and the right format, I run it through a compression tool.

I highly recommend tinypng.com. It is a free, simple online tool that strips out unnecessary metadata and intelligently compresses your images, ensuring they are as small as possible without losing visual quality. It works for both PNGs and JPEGs.

The Bottom Line

If your eLearning course takes three minutes to load, your learners have already checked out.

Stop uploading your images straight from your stock photo site. By taking a few extra seconds to resize, format, and compress your images, you respect your clients’ platforms, your learners’ bandwidth, and deliver a much more professional final product.

If your learners are complaining about slow load times, your media might be the culprit. Book a coaching session with me, and let’s audit your workflow to ensure your courses run as fast as they look.