Macro Magnification

May 15, 2010 Pete

I first got sucked into the world of macro photography when I received a set of Vivitar extension tubes for Christmas. The extension tubes fit between your camera body and your lens, which at that time was between my Olympus OM 4ti camera body and my Zuiko Olympus OM 50mm f1:8 lens. If I remember rightly the first ever shot I took was of dead bracken. I was hooked from the moment I looked through at this everyday subject, finding new patterns and detail in this small world.

Ever since, I have been adding to my macro lens set and equipment. For me a couple of the most important buys were the Olympus OM T28 twin macro flash and the Velbon Super Mag Slider. The former was very important when moving into high magnification work, as I found that the slightest breeze could ruin your photo even at a wide open aperture, plus if you use the wide open aperture your amount of depth of field suffers. The latter, gave me greater control on focusing on the subject. There are individuals out there who can shoot at this high magnification hand held, but I have yet been able to master this technique to any high degree of competence, and where possible will reach for my tripod and Velbon Super Mag Slider.

I want to use the following three shots of a bee curled up on a leaf on a cold windy day this month to show you the level of magnification you can achieve; how the depth of field will get tighter with the increase in the magnification you use; and how the use of flash becomes more important (personal view) with the increase in the magnification.

These pictures were taken for the purpose of this article, and so are not to the quality that I would normally accept or publish. All taken with the Olympus OM 4ti on Fuji Velvia 100 positive film.

This first shot was taken hand held with the Olympus OM 80mm F4 Macro lens on the Olympus OM Telescopic Auto Tube 65-116, using the Olympus OM T28 twin flash and Olympus OM T32 ND4 filters. Aperture was F11 and this is at 1x magnification:

The next two shots were taken again with an aperture of F11 this time using the Zuiko Olympus OM 38mm F2.8 Macro lens on the Olympus OM Telescopic Auto Tube 65-116 with the Olympus OM T28 twin flash and Olympus OM T32 ND4 filters. The difference is in magnification. The first shot is at 3x and the second is at 4x.

I hope you can see that with the increase in magnification the level of sharp focus (front to back) in the shot is smaller (tighter) each time.

I controlled the level of power of the flash, Olympus OM T28 twin flash, by using Olympus OM T32 ND4 filters on both flash heads. This was consistent across all of the shots to show you how the level of light to subject drops with each increase in magnification. So you will see (particularly with the x4 image) that with the same flash power and aperture, as the magnification increases the amount of light reaching the lens also reduces.

If I was to shoot without flash the resultant shutter speed would be reduced with each step up in magnification, so making hand holding or even tripod support impossible dependent on the conditions. In this case without the flash these pictures would have been assigned to the bin as blurred images due to the shake caused by the wind. If I were to be shooting with the flash at x4, I would normally increase the flash power by replacing the ND4 filters with the wide adapter filters or even shooting without any filters attached.

3x magnification: