One stop closer (minor level up for cheap pseudo macro)

Finally solved the depth of field issue using reversing rings.

I bought a cheap 52mm reversing ring for my cheap Canon EF 50mm f/1.8 several months ago.

This combination performed well enough as a poor man's macro solution, but my primary complaint about it was the inability to control depth of field because the lens didn't have manual aperture control. Since I couldn't close the aperture blades from the f/1.8 position, the resulting depth of field was ridiculously shallow (i.e. very few things were in focus).

It turns out that it is possible to close the aperture blades, but the method itself is as unorthodox as peeping from the other end of the lens.
  1. Attach the lens to the camera in the usual manner (i.e. the contacts on the lens are against the camera body).
  2. Narrow down the aperture in Manual mode or Aperture Priority mode.
  3. Hold down the depth of field preview button (if the camera has one).
  4. Remove the lens while the aperture blades are closed. They will remain in that position.
  5. Mount the lens in reverse.
This allows the lens to be used with smaller apertures while in reverse position. As expected, there was a significant increase in image sharpness.

f/1.8 versus f/22

<º))))>< ´¯`•.¸_¸.•´¯`•.¸_¸.•´¯`•.¸_¸.•´¯`•.¸. ><((((º>

For comparison, the shot on the left was taken with my IXUS 105 while the one on the right was taken with the 600D.

Although its minimum focusing distance is ridiculously closer (approx. 2cm versus the 11cm of the reverse ring setup), the IXUS simply doesn't compare to the amount of detail and control available to DSLRs.

<º))))>< ´¯`•.¸_¸.•´¯`•.¸_¸.•´¯`•.¸_¸.•´¯`•.¸. ><((((º>

It should be noted that this current setup with the reversing ring still does not yield true 1:1 scale macro. Canon's APS-C sensors have a width of 22.2mm, but this image below shows 32mm of a ruler. That's a magnification of about 0.69 or 1:1.44.

It's possible to get even greater magnification with the addition of relatively cheap extension tubes, but this would come at the cost of even less light reaching the sensor. There are two main methods for addressing the issue of insufficient light for macro photography.

The first method is to expose each photograph for a significantly longer period while utilizing a stable tripod. This is advisable only for static subjects such as dead bugs or still life; expect motion blur otherwise.

For the setup below, I relied on two desk lamps for the lighting. Due to the direction of light from these sources, I brought out the tissue paper cardboard roll lens hood once again to cut down the glare and  maintain contrast.

The second method is to make liberal use of flash to make up for the shortcomings of ambient light. This burst of light allows more reasonable shutter speeds to be used, but the lighting tends to be harsh and uneven. In the image below, I diffused the light by bouncing the on-camera flash twice.

Appropriately enough, what I used here to bounce the flash is a flash card which I made and used for Japanese class back in college. There happens to be a number of these stacked on my study desk, and I haven't the slightest idea if I would actually learn enough to pass the level 4 JLPT come December.

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