camera

Another Kind of Bellows

After being repeatedly frustrated by my camera's inability to take good photos of the tiny things I've been working on lately, I decided to look into putting together a low-end macro photography setup. A 'true' macro lens was well over my budget, so I did some reading about extension tubes and bellows and reversing rings, etc. To cut a long story short, I ended up buying an old set of macro bellows with a 60mm enlarger lens on the front. Annoyingly I found that I also needed to put a short extension tube between the bellows and the body because it wouldn't physically fit without one.

Here's my current macro setup. The top of the cardboard box is a sheet of thin white tissue paper to diffuse the light. I'm still pondering whether to add a second light source. It would probably help.

bellows1

bellows2

Here's the photo I took with this setup (full resolution available if you click through). It's a pivot on one of my concertina action boards that I repaired and modified (more about that in a separate post later on):
DSCF8291

I'm fairly happy with the result - it's way better than I could have managed with the standard lens - however I've run into a bunch of problems, some of which might be solvable, others I'll just have to live with.
  • It's really hard to focus it. Because it's a fixed-focus enlarger lens, the only adjustments available to me are altering the focal length with the bellows control (which also alters the distance between the lens and the subject and changes the magnification level), and physically moving the subject nearer to or further from the lens (which also changes the size and position of the subject in the frame). I can get it somewhere close to being in focus while looking through the viewfinder with the aperture fully open, but then I stop the aperture right down (which makes the viewfinder too dim to see anything in it) and take a picture and look at the result on the LCD to find that it's horribly blurry. In order to get one in-focus photo I need to spend several minutes making minute adjustments (which inevitably alter the composition as well as the focus) and taking test photos. Eventually I manage to get a photo that looks fairly sharp when I zoom right in on the LCD screen, then I upload it to my Mac and find that on the big screen it still isn't as sharp as I would like it. Grr.
  • There's light leaking in somewhere and I'm not sure where. The above photo was taken with a piece of cardboard shading the lens and bellows. Without it I get horrible fogging; the longer the exposure the worse it is.
  • There's lots of dust and a small hair on the camera's sensor. I don't know why, but it shows up far more obviously on photos taken with this setup than with the normal lens (though the hair has been bugging me for a couple of years).
  • The camera's manual exposure meter doesn't work; it just complains that it doesn't know what aperture the lens is set to. I had expected to have to manually adjust the aperture and shutter speed but I didn't realise the meter wouldn't work at all. Not a major issue with the kind of static photos I'm taking though; I just take every photo at the minimum aperture (to get the greatest depth of field) and make an educated guess at the shutter speed, then adjust it up or down as necessary until it looks right on the LCD screen. Then bracket it for good measure (from experience, what looks right on the LCD often turns out to be about a stop underexposed on the big screen).
  • The minimum magnification level is still fairly strong compared to the maximum I can get with the standard lens (in other words, there will probably be objects I want to take photos of that look tiny with the standard lens but don't fit in the frame with the bellows).
  • The front end of the bellows rail gets in the way a bit at low magnification settings (I can't just move the rear part forwards because the bottom of the camera body fouls on the rails).
  • The tripod setup is rather cumbersome and I keep finding that the tilt head has sagged forwards under the weight of the bellows while trying to adjust the focus, such that the subject is no longer in the centre of the frame. I suppose a counterweight on the back would help.


Bonus photo - part of a lit 60W tungsten light bulb filament at maximum magnification:
filament

Comments

If you're shooting macro, more light always helps. You're imaging a very small target area of a few square mm and focusing it on the complete sensor chip so there aren't a lot of photons to spare. For shooting static images there's no problem with long exposures other than camera shake -- cable releases or time-delay are your friends here -- but you can add a spotlight or similar to help you focus and then switch it off and rely on the diffuser box for the actual exposures.
Hi Nojay! I need to play around with the lightbox setup a bit to get more light onto the subject. At the moment the angle of the light source is less than ideal if I have to tilt the subject to get it parallel to the camera. I suspect shake is causing problems at higher magnification levels despite using a cable release, probably from the mirror clunk (this body doesn't seem to have a mirror lock-up or delayed shutter mode). The sensitivity is set to ISO 100 to minimise sensor noise, which with the single light source shown above is giving me exposure times in the region of two to eight seconds.
I think you're doing the right things, mostly. It's a long time since I've done stuff like this (microphotography of macro objects, somewhat classified stuff) so I'm working from memory but here's what I remember.

Camera shake for macro work is a major problem as small movements are magnified and cause noticeable blur. A regular tripod isn't a good support for making long exposures, I'd suggest building a more solid frame to carry the camera and bellows unit. Alternatively mount a big heavy plate under the camera to add mass to the tripod head and dampen vibrations. The counterbalance idea is good too, given the mass and extension of the bellows unit in front of the camera.

Lighting is the next big problem. A high-intensity spot to illuminate the point of interest will help you solve the focus problem. Oddly enough you actually want a longish exposure to eliminate mirror bounce -- a 1-second exposure after the mirror movement means 900mS of steadyness and only 100mS of vibration from the mirror movement. Another alternative, assuming you can rig it is to set up a couple of close-mounted flashes to fire a few hundred mS after the shutter is triggered and the vibrations have damped out again.

The sequence would be:

1. Focus using high-intensity spot with lens stopped down.

2. Switch off spot and room lights.

3. Arm flashes, aimed through diffuser box.

4. Fire shutter with cable release. Flashes fire about 200-500mS later. Exposure finishes any time after. Don't breathe and tell the cat to stop stomping around.