The “antimatter” of airbrushed portraiture!

Several years ago, I invested (on a whim) on a transmissive UV filter for my Rolleiflex. Unlike a regular UV filter, which cuts the amount of light in the UV spectrum to avoid unsightly colour effects (that bluish tinge on bright white things), or distance haze, a transmissive UV filter cuts everything BUT light in the UV spectrum!

Folks who’ve done a bit of black and white portraiture might know that using a warm filter is very flattering to human skin – so a yellow filter is nice, a red filter even nicer, and Infrared gives skin a positively ethereal glow (whilst making eyes seem alien and slightly scary). On the other hand, a blue filter is not flattering AT ALL, and the more blue-violet you go, the worse it gets, with every bruise, blemish, or bit of sun damage becoming progressively more visible.
And so, once I’ve explained this, it becomes difficult to convince a potential portrait sitter just how cool an experiment this would be to try, which makes me doubly pleased that my pal Adele and her friend Phillipe agreed to be guinea pigs for a UV portrait sitting recently.
Before making the photos, I had to think about how to light them. The filter in question is rather dark – like welding-goggle glass, and so you lose a fair bit of light with it. I calculated (by metering through it with a spot meter) a loss of 7 stops. That means an normal exposure at f/16 would become f/1.4 with the filter attached. Yikes! I would need to light VERY brightly, and perhaps use a faster film. Additionally, tungsten lamps omit barely any UV light, so they weren’t going to be any help – studio flashes would be the go, BUT… modern studio flashes have a golden UV coating on the flashcube, specifically to prevent UV light being emitted (so white looks “white” without a blue cast). Crumbs!!
Fortunately I have a couple of antique British Courtenay “Solaflash” studio flashguns, that look like spaceships from Blakes 7, that aren’t evolved enough to incorporate such forward thinking technologies, so I duly set them up in a crosslight pattern, and did some incident readings to see what sort of light I could get.
Now, just because I’d thought this all out unfortunately doesn’t guarantee I’d remember it all on the day – so the Rolleiflex was duly loaded with Kodak Plus-X – not an especially fast film at all (ISO 125) – but I have had some success pushing that film in development to ISO 400, so I decided to give that a whirl.

As you can see from this diagram – the key light is about 30cm away from Adele/Phillipe, and yet with the 7 stop loss of light, I ended up exposing everything at f/4, and at 1/250th second (a leaf shutter syncs with flash at any speed – so fast is the go (but not faster than the pocket wizard can handle!)). To fill the frame, I used a Rolleinar closeup adapter, and with that and the aperture, you can see the depth of field is very narrow indeed!

And the effect? “Leathery”! I would really like to photograph someone freckly, as I think that would come out a treat. Phillipe’s glasses must have a UV coating on them because they are completely black. Interesting, n’est ce pas? The Plus-X I developed in Rodinal 1:25 for 9 minutes, and that made for some satisfyingly dense negatives, even with that much under-exposure. I must remember that.