PhotoProject :: Experiments in Free Lensing

Deep in the haze of jet lag after travelling and waiting at airports for a combined 30 hours and crossing 10 time zones, including losing an entire 11th August somewhere  over the pacific, I was home and listening to last week’s This Week in Photo/Family. Just a small part of the discussion was about free lensing. Using the camera without the lens actually screwed in.

The creative potential immediate switched on a light blub in my mind so I just had to try it out for myself. Rather that take the cautious approach of perhaps reading up on it or even looking for a you tube video. I jumped in! After all I had already begun a taking a few photos using no lens at all. All seemed reasonable and it was, but here are a few pointers to make it easier to get decent results.

 

1. [Optional] Take a photo of your approximate intended composition and the not eof the setting you used to get a good exposure, because you need to make the free lens photos in manual mode (because the lens is not attached). Don’t forget ISO & White Balance (usually Auto WB is a good start)
2. Detach the lens and set focus (to infinity is fine), because you will be actually focusing differently later. Most digital lenses no longer have a f stop rings and the default is to leave the lens open right up (to make focusing easier if it is open until you press the button). if you have an older (film) lens with an F stop ring on the lens open it up to the largest size (so let as much light as possible through). Switch your exposure to Manual (M)
3. I found how I hold the lens makes a big different and I found the best approach is to hold the lens firm between my thumb and fingers and laying it on my fingers of my left hand. Then I slid the camera (without a lens onto the ball of my thumb and open palm until it almost reaches the lens and about to connect. This makes sure the lens axis is pretty close to being aligned with the sensor.
   
4. Next I needed to orient the lens (it can have a slight tilt) and move the camera back and forth until the image in either the view finder or better still in live view, on the screen on the back of the camera. The focusing working exactly like using a magnifying glass. Depending on how far from the subject you are you need to move the magnifier back and forth until the (enlarged) image comes into sharp focus.  That’s all you need to master. The further back you hold the lens the further away you may need to hold the camera. It is generally only small adjustments to the camera lens separation that are required and it is not hard once you get the hang of sliding the camera behind the lens.
   

The depth of field that is in clear focus (the sweat spot of focus) is typically very thin. So only a small area of the photo might be in focus. Slight tilting of the axis of the lens relative to the sensor will move the sweat spot around the resulting image. This is where the real charm and creativity comes it. and not always predictable

 

Make a super Macro photo.

Using Free Lensing you will be able able to get the lens closer to the subject and bring the camera close without much tilt will work exactly like extension rings and give you a significant enlargement/macro lens effect.

 

Make a tilt shift effect

This can be a little of a challenge but slight tilts, using your fingers on the lens, rather than the camera, will elongate the image on the sensor and careful selection of an offset focus plane ( the “sweat spot” is actually a plane) can give the resulting image with a tilt shift style appearance.

 

Just have fun

The gradual out of focus drop off at the edges can make free lens photos wonderfully dreamy and artistic. Go and have some fun with this method, it will cost you nothing if you has a digital camera with an interchange lens.

 

There are a couple of obvious limitations and problems. Because the camera is open there is a significant chance of light leakage and flares (which may just be represented as a colour fogging). This is particularly likely if you are photographing into the light (ie a backlit subject), but such flares can be used creatively and really add to the dreamy effects.

There can be very strong vignetting as the lens is titled, again this can ruin a shot or be used creatively.

The other concern is dust on the sensor. Because the camera is open you run a real risk of getting dust and dirt and your sensor. I am quiet happy to clean my sensors with a an air blaster (I take the brush off the hand blower). So I recommend  it is good practise to have a air blower handy lift the mirror and do a dust blast with the camera inverted (so any dust/dirt falls out of the camera safely) before you reattach the lens. Its probably also a good idea to practice the free lensing technique indoors until you are proficient enough to minimize the open exposure outside.

I doubt free lensing is a particularly new technique. I joined a flickr group that is at least 7 years old. The original lensbaby, a popular photographer’s toy, is basically a flexible tube that achieves the same as separating the lens from the camera (it just covers the gap, avoiding the light leaks, and a has simple single aperture lens and costs much more than just unscrewing the lens)