While test various styles of diffusers I came across a one involving a rather unique method of removing highlights: cross polarization. As detailed in Wil Hershberger’s article here, this technique involving a polarizing filter and special polarizing film to cover the flash(s). I constructed a similar setup to the one shown in Wil’s article but with the Canon 100mm macro lens and MT-24 EX macro twin lite.

On the whole, the results of these tests were fairly pleasing – little to no highlights and pretty good color. But this did not hold for insects with iridescent coloration; the images of these species were dull and lacking in much of the natural coloration. Below is a combined series of the better images:

In all I found this method reasonable for only certain insects – ones with much iridescent coloration (particularly tiger beetles) were not well represented by this method.

In my previous post I detailed my transition from using Canon’s MT-24 EX Twin Flash to the Canon 580 EX for macro work. Now, at last, here are a few samples of the lighting produced by the new setup. I have been quite pleased with the diffusion provided by the 580EX/Micro Apollo softbox combination – take and look for yourself and let me know what you think…

When I was first in the market for a camera I chose Canon for their macro system and especially the capable – and unique – MP-E 65mm 1-5x macro lens. Over the past few years of using it I have found it near indispensable and always keep it on hand when in the field.

My main problem with the Canon macro system has come to be the Canon MT-24EX Macro Twin Lite Flash. While extremely versatile and compact, this little flash unit is quite harsh unless diffused well (like Alex Wild’s setup) and there are some annoying issues with its effective range and the flash head angle when coupled with the working distance of many lenses.

The diagram above depicts the working distances of the MP-E 65mm lens at 1:1 (1) through 5:1 (5) and the light cast by the Mt-24EX flash head when in the “default” position pointing down.

Quality of the Lighting

With my homemade diffuser setup the area from 2:1 to 5:1 is quite well lit – the lighting is very even and soft, but almost flat – without much depth. This can be fixed with an adjustable flash shoe which the  the light  and gives a far better result in many situations.

But at this  angle the flash can cast a shadow on the near side of the subject particularly when photographing a very small subject and this led me to stop using the adjustable flash shoe option.

At magnifications less than 2:1 it is hard to get good lighting with the MT-24EX as the distance between the subject and camera is very often too great for even my versatile tracing paper diffuser.

In the example above, I used the MP-E 65mm lens with the flash diffused. As you can see the image on the left (taken at about 2.5:1) is quite well lit versus the image on the right (taken at 1:1).

If you compare the relative distances of the two subjects from the flash heads in the diagram above it becomes clear how the diffuser is far less useful at the greater working distance.

I have tried a variety of different diffuser setups, none adequately diffused light throughout the entire range of the 65mm lens let alone to the near range of Canon’s 100mm macro lens, even with one or two extension tubes.

Position/Angle of the Flash Heads

In the above image you can see how the light from the flash strikes the subject on from the side rather than the top – a major issue when using a lens in the 100mm+ range.

The mounting ring which attaches the flash heads to the lens raises them only a few centimeters above the lens barrel, a huge problem when trying to shoot a subject that is larger, as in the photo above.

Though this image was taken with a 100mm lens, two 25mm extension tubes, and a custom bracket (which held the flash heads up and out toward the subject) the lighting was no better than that from a ring flash, probably worse.

Above is shown the path of the light from the MT-24EX to a subject at the minimum focusing distance of the Canon 100mm macro lens.

Conclusion:

After over two years of using the MT-24 EX and a whole lineup of diffusers my conclusion is that this flash is very good for use with Canon’s 65mm 1-5x macro lens in the 2:1 to 5:1 range, providing lighting that, when adequately diffused, is very good.

But even with in the short span between 1:1 and 2:1 a diffuser which worked well in the former range is now of little to no use. This is the same when the M-24EX is used with a 1:1 50mm to 100mm macro lens due to the angle of the flash only a few centimeters above the lens.

Now I and anyone else can almost certainly make a diffuser which covers a given portion of the MP-E 65mm’s or 50mm/100mm range, but it is creating a diffuser that covers a greater range which will actually make this unit practical.

After spending two years plus trying to find ways to bridge the gap I decided to take a break from the Mt-24EX and tried using the Canon 580EX with a small softbox.

With this new arrangement I have been quite happy – only in one or two incidents has this combination presented some trouble which was easily correct with a minor adjustment of the flash’s position. And using this setup I can switch from the MP-E 65mm to a 50mm lens without having to fiddle with arranging the MT-24EX or diffuser, just a swift adjusting of the bracket and the flash is nicely positioned.

On the left a shot taken with the MT-24EX and on the right a shot taken with the 580EX – what a difference!

Please let me know what you all think about MT-24EX – I look forward to hearing what you all have to say!

For me there was no rest after final exams were over; it was right off to southern Utah to begin work on a summer research project on the Coral Pink Sand Dunes tiger beetle, Cicindela albissima.

I’ll write more on the research itself over on my cicindela blog, but for now a bit on photographing the beetles.  This was my third trip out to the dunes and as ever I could not wait to get some shots of the beetles, now with an improved set of equipment, including a shiny new Canon 7D. It was not until the end of the first week of my stay that I found time to take a morning off to focus on photography.

As with most tiger beetles the adults are quite flighty and the best time to get close enough to this species for a good photo is mid morning when they are just emerging for the burrows which they spent the night in.  My first tries were less the successful; there was the usual slow chase as I followed the uncooperative beetle about and then at last take a few shots.  Unfortunately I had set the flash, a Canon 580 Ex speedlite with a Micro Apollo softbox, too far away from the subject and as a result the lighting was just a little too harsh.

Annoyed by this rather poor first attempt I switched focus to capturing some video of these intriguing beetles. This was done taken with my new Canon 7D SLR which is capable of  recoding  HD video, a feature which I was interested to explore. The video set up was bare bones with only the harsh sunlight for illumination, a tripod, and a borrowed Canon 180mm macro. This solid lens allowed me to get fairly close-up shots while remaining a fair distance away, ideal for minimally obtrusive video work. I hope to soon edit together a short video from the footage I shot and will have that up in the coming weeks but here is a neat clip.

My second attempt at getting a photo of the adults was similarly lackluster. I had set up an old Nikon Ais 55mm 1:2 macro lens with an adapter on an extension tube and the flash was now moved closer to the subjects. With this setup the distance between the camera and subject was quite short requiring a good deal more care in getting near the subject. It was during mid evening and the adults were still very active when I found a mating pair and got right up to them. As best I could I focused while the manual aperture was set at f/11, darkening the viewfinder. When I thought the focus was about right I snapped a few shots and, not surprisingly, spooked off the beetles.  Unfortunately the focus was a several millimeters off and only the tarsi of one beetle was actually in focus. The solution to this problem was very simple – something modern cameras do automatically – open up the lens and let as much light as possible in, then stop down the lens to the desired f-stop (it does take a bit of guessing/counting the clicks of the aperture ring to get it right).

My third try went far better; it was after the day after the first rain in over a month and with the temperature lower than usual the adults were slightly sluggish, by far easier to approach. I used the Nikon 55mm macro,  extension tube, and 580 Ex with diffuser as before; this time my first attempt was successful.

In this shot the spectacular colors of the beetle can be fully seen and there is no harsh/obtrusive shadow present. Any comments on the lighting or questions on the setup? I will have more details on photographing these beetles – particularly close-up shots – and some notes on photographing the larvae in later posts so stay tuned!

From a month-long stay at Coral Pink Sand Dunes state park where I was doing research on Cicindela albissima, the Coral Pink Sand Dunes tiger beetle.

Will have more posts soon and hopefully some videos about equipment and the like – stay tuned!

come the bugs! For me it was the start of spring break and with the temperature hovering at 80°F this past Saturday was near ideal, so I ventured out in search of many-legged quarry; the results of this search were pleasantly surprising.

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