If you’ve toyed with the idea of playing with a plastic camera, such as a Lomo or a Holga, but have been put off by their reliance on film, a ‘lo-fi lens’ may be the answer. While Lomography offers an adapter for its Diana lenses, I much prefer the ‘digital’ Holga lenses.
These lenses are designed specifically for digital cameras, but retain the classic plastic construction and design of their medium-format namesake, complete with four fixed-focus distances.
Of course, the term ‘focus’ is used in its loosest sense – as with a ‘proper’ Holga camera, nothing is going to be overly crisp.
You can also expect strong and uneven focus fall-off at the edges of the frame (even on an APS sensor), plus heavy vignetting and chromatic aberration – everything a lo-fi lens should give you!
A word of warning, though: although Holga lenses claim to have a (fixed) aperture of f/8, they can be much slower. The Holga lens I use is in the region of f/32–f/45.