I think it’s neither. It’s more a game of compromises, and it depends on your goals for the site. It also depends on how it’s designed and built.
Let me break it down into a few distinct points:
1. Too many slideshow images are never good. Nobody is expected to sit through 50 images or more in a slideshow these days. It just means you were lazy with your image selection/editing.
2. If the slideshow is a splash/intro page (blocking the site navigation), then it’s “user experience hell”, yes. Anything blocking the user from reaching the main navigation and homepage content is bad.
Sure, such a splash page is visually impressive to parts of your audience, but really annoying for the rest.
3. Slideshows with no left/right arrows are bad. You’re forcing visitors to wait for images to change; you’re taking control away from them. I don’t think they’ll reward you with their patience.
4. Keyboard navigation is a nice feature. I sometimes love switching a page to full-screen and using keyboard arrows to navigate a slideshow.
5. Thumbnails can help. Some users like to have the option of jumping from one image to another, and providing thumbnails is great for that. Full-screen homepage slideshows are usually exempted from this though.
6. For portfolio sites (where the goal itself is to showcase your best work), full-width (or full-screen) slideshows work well, they can really impress your audience. But make sure the website’s main menu is still accessible. Otherwise, it becomes a hindrance.
7. The slideshow needs to pre-load images in the background, so transitions work fast. Even if you have a small selection of images in the slideshow, users should not see a loading animation for each one. (Some older websites still need to wait to load all images before starting the actual slideshow, which is obviously a bad thing).
8. Another common slideshow annoyance (for regular slideshow at the top of the homepage) is when images get cropped too much or when the slideshow changes in size with every image (pushing the rest of the content down as well). The fix for both problems is simple: properly crop and size all slideshow images to have the same aspect ratio.
9. And then there’s the issue with vertical images. Since slideshows usually have a horizontal layout, vertical images can leave a lot of empty space to the sides, not looking as good. You could look into displaying two vertical images side-by-side at the same time (if your slideshow allows it), or preparing photo collages beforehand (one single image file containing two or three images – basically a “diptych” or “triptych”).
10. Playback should be automatic, but with the option to manually go back and forth between images. It’s good to provide both options.
11. Transitions between slides should be kept fast (<500ms) and simple. So nothing “creative” like this:
12. Next & Previous buttons/arrows need to be in a steady place. Nobody expects to move their mouse cursor when clicking “next” in a slideshow.
Only somewhat related to this topic, but make sure you’re also properly sequencing images in your slideshows.
Most of the times, slideshows bring on more problems than they’re worth:
- they’re in flash and/or not working on mobile devices
- they bring extra header tags in the source code, affecting SEO
- they can impact the website’s performance
- they push important content lower down the page
But photography websites need to be visually impressive, so slideshows will always have their place. Just as long as they’re built right.