Almost All Horizontal Portfolio Themes/Plugins Have A Serious Flaw (Making Them Professionally Unusable). Please consider this.

I work in the image industry and I’ve been searching for a horizontal scrolling portfolio theme.

Essentially, I need a theme/plugin like this: http://wpshower.com/demo/?preview_theme=expositio

However, I searched for many other themes, and for pretty much all of the horizontal portfolio themes on the market—scrolling through the images by clicking and dragging doesn’t work. I’ve tested some in 4 different browsers as well. If you use something else other than a trackpad, the UI is difficult and unpleasant (or non-existent) for many users/clients.

The other options, if you don’t use a trackpad, are that you either have to use the keyboard arrows or the scroll wheel. The arrows usually move the images by only 50px, and clients have to guess this. Still, it’s not unusable.

For the mouse wheel, which is commonly what is used, clients have to guess that’s how it works (I was a Web designer for many years and it took me some time to guess this).

How many clients will want to view your work, not succeed and just leave your website? 15-30%? And out of the 70% that don’t leave right away, what about clients who have a bad mouse wheel—such as those $5 Dell mice or the old dreaded Apple mice? How can they not associate the bad and unpleasant UI of your website to the service you are offering?

To sum up, please consider this: what is the percentage of the visitors/clients that have a good mouse wheel, or a trackpad, as well as knowing that’s how the portfolio works? 5-15%? This meaning 85-95% of visitors/clients will be annoyed by your website and/or won’t be able to view your work and will leave right away.

Why is this the case (or I have missed most of the working horizontal portofolio themes)?