I'm a life-long photographer (DSLRs for 18 years) but I haven't shot more than a handful of photos with a diffuser before... mostly because I don't do a lot of portraiture, and because there really was a big difference between the economical diffusers and the expensive ones, the cheaper ones not really looking that professional.

Anyway, I decided to try this one. I'd love to write you a comprehensive, scientific, analytical review, but this filter has left me a bit baffled... but perhaps I'm just confused.

I've thought that diffuser filters are good for a few things:
1. Portraits - softening the skin
2. Making high-contrast images a bit "dreamy"
3. And maybe for giving a more dramatic effect for points of light in a low-light shot

The weird thing is, when I shot nearly identical shots with my Canon full-frame with and without the filter, I was actually getting sharper details and richer colors USING the diffuser! This of course, is not expected. Now, I was shooting hand-held, but I can't believe that in every case, I shot more steady when the filter was on than I did when it was off. But whatever it was, my test shots came out sharper and overall better WITH the filter. But to be honest, unless you peek at the pixel level, there was no noticeable difference when looking at the full image.

I suspect it comes down to focal range and that a diffuser works better with close-up shots... yet my static shots of highly-detailed subjects hardly showed a difference at all.

However... in the scenario where a diffuser is most likely to be desirable - portraits with natural skin... I DID see a difference... subtle, but definitely a softer touch to textured skin.

So... I can recommend this for portrait shots... and I can even recommend it for landscape shots - I'm just not sure WHY they came out slightly better with the filter!