Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Photo#250284
My setup

My setup
Medford, (~25 miles east of Philadelphia, PA) Burlington County, New Jersey, USA
The Problem: Upon finding BugGuide, I wanted to share images of the magnificent detailed small beetles I could see when viewing them under magnification through my Stereoscope. I could see intricate detail with excellent depth of field with magnification between 6 to 40 power on subjects which mostly ranged only 2 to 7 mm. The problem was that with my present equipment and budget I wasn’t able to produce images that seemed close to the clarity and “showiness” that I could see with every gaze through my stereoscope.

The Failed Attempts: I had a Canon Powershot A610 (midsize point-n-shoot) (and later A640) to work with, which has excellent macro focusing capabilities (right down to zero cm) and excellent resolution. So the logical first step was to simply point the camera through the stereoscope’s eyepiece, and capture the same wonderful scenes as my eyeballs. This did require the lens to be zoomed to max telephoto (4x) to somewhat match the camera’s field of view of that of the eyepiece. While the resulting images captured some of the detail, they were not as sharp as what I could see. And they suffered greatly from lack of depth of field, clarity, and a few other things. (the before)

Budget Busters: At least two very acceptable solutions were known to be available, but neither came close to fitting my discretionary spending budget. Canon’s MP-E 65mm 1x-5x dedicated macro seems to be the lens of choice for BugGuider’s smallest subjects, and is especially suited for live subjects, unlike some other options. But at ~$900 for the lens, ~$600 for the accompanying MT-24EX twin macro flash, and say ~$600 for even the most basic Canon DSLR body, quickly adds to over $2k, which is more than I could afford. .

The other common system known to me that clearly produces images of the quality I desired or better is the Automontage system. The system consists of an optics setup similar to a stereoscope’s with a digital camera mounted onboard to capture the images. The whole setup is computer controlled to both capture images directly from the camera, and mechanically step the focus of the optics. Images are captured at each focal setting, and the resulting image series are “stacked” by software to yield a composite image with depth-of-field much greater than any of the single images alone. These systems seem to the purview of universities and institutions, I assume mainly due to price. But I have actually no idea what they cost. See some BugGuide pictures/info on them here , and check out Jeff Gruber’s stunning results in his posts.

Eureka! The Solution: The solution for me (both optics and budget) turned out to surprising simple. And in the end did not involve a Stereoscope. After reading several web articles on “optic setups for macro”, and most designed for non-SLR cameras, I settled on the “reverse mounted lens” technique (see an excellent explanation here. It’s actually been around since before digital cameras and was used to produce images similar to those of Canon’s MP-E 65mm. All you really need is a point-n-shoot similar to mine and an old “fast” SLR lens.

My basic parts list includes:
Canon Powershot (A640 in my case, but almost any A, S, or G series will work) ~$250
(must be a Canon Powershot for firmware availability)
Canon CDHK firmware hack for focus bracketing (freeware)
Powershot lens adapter sleeve, normally used for auxiliarly lens ~$10
fast (f1.4) 50mm SLR “prime” lens (used from e-bay) ~$50
various filter and reversing rings to mount 50mm lens to lens adapter ~ $20
Stereomicroscope stand with fine focus (other setups possible) ~$100
Halagen spot lights or fiber light source ~$120
2x telephoto auxiliary lens ~ $80
Stacking software (freeware available)


The 50mm SLR lens is reverse-mounted to the Powershot’s lens adapter sleeve, which is of course mounted on the Powershot using the standard attachment lock. The rear of the reversed SLR lens is now pointing at the subject / bug. The working distance is now the same as the old SLR’s film plane – about 35mm. The Powershot must be zoomed out to 4X max (29mm on my A640 and most others. The S series can go much further), to best match the 50mm lens’ field of view. You gain magnification as the focal length of the Powershot increases in proportion to the focal length of the reversed lens. A very fast lens is needed (low f-stop) to provide wide enough glass. And several articles have explained why 50mm is optimum, as opposed to wider angle lens (which generally don’t come as fast anyway). With the Powershot at 4X and a reversed 50mm lens, the resulting usable image is about 13mm, and covers about 75% of the length of the frame (or about the full height). The corners are all blurred and a little dark, but the final images will be cropped anyway. Adding a 2X tele auxiliary lens between the Powershot and the reversed 50mm doubles the ratio of focal lengths (just like it should), and results in about a 5mm usable image, covering about 50% of the length of the frame. Again, cropping will eliminate the blurred edges. I’ve briefly tried using a 3X tele aux lens (higher focal ratio and magnification), but initial results were not favorable. But I have yet to apply this technique with the “superzoom” S series, which wouldn’t add all that tele aux glass. See dpreview.com for great info, specs, and reviews on Powershots, past and present.

Depth-of-Field challenges: All this glass gives great magnification (small bugs spanning a significant percentage of the frame), but with the Powershot zoomed all the way out (and worse when the tele aux is added) depth-of-field can shrink to a millimeter or less. I overcome this by taking multiple images of the same non-moving subject at very slight different distances. There’s several ways to accomplish this: move the camera (like the Automontage systems), move the subject (a compound microscope stage might be used for this), or change the focal setting of the camera. I use the last method. The Canon firmware hack, CHDK wiki, allows among other possibilities, the ability to script or command specific manual focus settings. You first load the replacement firmware on the memory card, and then write scripts which execute when you push the shutter button once. I use a simple script to manually command the camera to focus to one distance, take a picture, then focus to the next slightly different distance and take another picture, and so on. You can dictate the size of the distance steps and the number of them, or just about anything you want. Through mostly trial and error, I’ve found a stack of 15 different focal distances is more than sufficient to overlap the DoF for any bugs, with or without the 2X tele. Start near minimum focal length, and step out. You quickly reach diminishing returns well before approaching infinity. I get the focus close using the Stereoscope stand to hold the camera setup, and then just hit the shutter release and stand back while the script snaps off the images. Then it’s off the darkroom, or rather the computer, to download the images, stack them together, and crop and tweak the final composite.
While the results are clearly not as good as many of the BugGuide posts using different equipment, what I found got me to my desire of being able to share images comparable to what I can see through my scope. :)
(the after),

Images of this individual: tag all
My setup My setup My setup My setup My setup

Depth of Field
Have you tried stopping the cannon lens down by hand?

You may need a longer shutter speed, but I would think you could gain some depth of field

 
Thanks,
no I haven't tried manually stopping down the SLR lens, and I'm not sure I know how. These Canon SLR lens do have a manual f-stop ring (seen the images), but to enable best manual focusing (pre-dates autofocus:) the lens/camera kept the lens wide open until shutter release. There's probably a tab or slider on the back of the lens somewhere that needs to slide to actually stop the lens down to the manual setting, but I haven't been able to figure out which one. And it might have also required a electronic enabling, via shutter release. If you have any tips on how to accomplish this, please let me know.

 
To top down the lens manually
To top down the lens manually, mount the lens, set the camera to manual mode, pick your aperture, then press the DOP preview button - its the small button on the front of the camera below the lens mount. Hold that button down, and remove the lens.

http://photocritic.org/macro-photography-on-a-budget/

Great work btw, I love the detailed pictures!

nice
Great writeup Tim. Nice to see some of the other setups people have come up with and are using. Thanks for pointing out the firmware hack site. I may have to use some of that functionality when I'm shooting in the wild with my A630.

Oh, and thanks for the compliment. The quality of your images is definitely approaching mine and I didn't have to work nearly as hard. Great job. Lighting is looking a lot better. Do you just use a single fiber optic light source (with 2 lights)?

 
Thanks Jeff,
Currently, all shots were actually lighted with 3 halogen "mini" spotlights, 2 50W and 1 20W, positioned ~18 inches or less from the subject. (I didn't own a fiber light (and had never even seen or used one!) until recently when I got a used Nikon MK-2 dual pipe off e-bay for ~$100) For diffusion, I usually simply use a white frosted plastic 35mm film can with the bottom cut off. I love making use of old film camera stuff in this "new" digital setup! I still get some shine on some beetles, so occasionally I'll throw a strip of paper vellum (sp?) in between the offending spotlight.

Any lighting tips or critique you can offer would be appreciated! And do use that firmware hack for other things. It provides exposure bracketing to the A6XXs, which is handy for lots of subjects beyond bugs. And just the full-time battery meter alone makes the download worth it.

 
We (myself & entomologists at
We (myself & entomologists at CDFA) have adapted a fairly inexpensive LED ringlight (made in China) into an effective "dome light" [see: http://www.cdfa.ca.gov/phpps/ppd/entomology/dome.html ]. I have also used this dome light as a macro stand for a Nikon Coolpix (resting the camera directly on top of the dome). This certainly could be done with a Canon PowerShot, and probably many other digital Point & Shoots. If you added in your firmware hack (with a PowerShot), you could no doubt make a really neat, portable, inexpensive 'Macro-stacking Stage' based on this dome light apparatus.

 
Just wanted to make your link active:

 
Thanks Dr. Fisher,
I'm been meaning to try a LED ring light sometime. I might have to modify the dome design a bit, to work with my short 35mm working distance, but I like the concept.

 
Tim, the minimum
working distance -- with the KD-200 dome system -- is about 20mm (that would be the distance from the outer dome surface to the specimen). For a portable unit (my interest in using a PowerShot/ firmware hack stacking outfit), I think it may be necessary to add in a table top tripod -- to hold the camera really steady for an extended period of time. This would allow someone to easily carry the gear to a Museum/ University collection to take quality photographs of insect specimens; for home or office use, a less-portable dissecting microscope base would be best.

Tim, that's an ingenious and
Tim, that's an ingenious and effective macro-stacking system you've developed; congratulations. Thanks for sharing your set-up with BugGuide.

 
Thanks,
hopefully others with similar needs and budget limitations may benefit.