brainstorms

Thursday October 20, 2005

impressionist optic: notes on a lensbaby

i recently obtained a lensbaby 2.0. this is an unusual bit of optic that produces high degree of blurring for impressionistic, ethereal results. here are my field notes and some images i made with a nikon d70. [this is not a thorough review; i have not tested the lens in a disciplined way with various aperture discs and compared to other optics. i also have not looked for color fringing and other aberrations due to high refractive index. i have used it with film, but do not have the results yet]

quick summary: for some photographers, this is an expensive, tiltable alternative to a spare daylight filter and some lip balm. [i have seen stunning images made that way] it is less messy, but harder to control, harder to focus, no metering. pretty out-of-focus highlights. not very sharp. in its simplicity, it does have a certain photo-geek charm; it is fun, and students will probably love it.

• essentially a finger-focused mini bellows unit: a lens attached to a short bit of flexible ribbed tubing that can expand and contract (accordion) and bend. metal parts appear to be machined aircraft-grade aluminum alloy.
• focal length appears to be around 50-60mm. fixed interchangeable apertures f/2.0 [f/2.8, f/4, f/5.6, f/8]. [close focus tbd]
• even though iris/leaf diaphragms have been around for nearly a century, lensbaby will have none of it; f/stop is controlled by dropping a circular disc into the lens cup. this disc floats in front of the lens with the help of three little magnets. there is one advantage to these discs: since apertures are perfectly circular, out-of-focus highlights will also be nicely round and pleasing to the eye.
• maintaining a good focus is difficult. remember that you are propping and adjusting the optics with your fingers to get it to focus and stay focused, and also trying to keep the camera steady. in other words, you need steady hands, strong fingers and good light for fast shutter speeds. if you have the camera on a tripod with a flexible ball-head (i use a manfrotto 222 for this sort of thing. i will soon move to a 322RC2), you have a better chance of getting a good image, but obviously this restricts movement. i think a monopod would be ideal for this.

• tilting the lens exaggerates the effects of its high refractivity. it moves the sharp area for better compositions, though focus control becomes much harder.
• the lens can be shifted [keeping the optic parallel to the sensor plane] only a very tiny bit, and i doubt this is useful.
• my preferred hand-held technique is to keep lens length and tilt as fixed as i can and slowly rock back and forth until i get sharp focus. [raindrops image was made that way.]
• this is a 35mm optic and on my other nikons [eg. fe2] large and bright viewfinders make it easier to get and keep focus. [most dslrs crippled with 16x24 sensors seem to have awful viewfinders, which makes it harder to use this optic]
• a lightmeter is necessary for film and very helpful even with a DSLR. [for some reason, decisive moments do not hang around while i experiment with the exposure.]
• this is a cute and useful optic, but just an optic. worth remembering that it is only there to help us make visual statements about things that matter to us. if we just care for the special effect, there is always photoshop.

[images: emma cheeta furball yigit. varley house lights. raindrops on smoketree leaves]