MYN – Sometimes it works; sometimes it doesn’t.

A Shadow Darner dragonfly (Aeshna umbrosa) exuvia, collected and identified by Andy Davidson near Richmond, Virginia USA, was photographed against a pure white background using the “Meet Your Neighbours” (MYN) technique.

Shadow Darner (Aeshna umbrosa) | exuvia (face-head-dorsal)

Sometimes the MYN technique works; sometimes it doesn’t work as well. For example, this specimen has clear “eyes” that are clearly shown in the first photo and mostly blown out in the last photo.

I’m fairly certain this problem can be solved by “staging” the subject on a clear surface raised above the white background. In this case, the subject is only a few millimeters above the background. Further experimentation is planned.

Shadow Darner (Aeshna umbrosa) | exuvia (dorsal)

Related Resource: Pop quiz: Sex the exuvia.

Copyright © 2020 Walter Sanford. All rights reserved.

Pop quiz: Sex the exuvia

An odonate exuvia was photographed against a pure white background using the “Meet Your Neighbours” (MYN) technique.

This specimen is a Shadow Darner dragonfly (Aeshna umbrosa) exuvia, collected and identified by Andy Davidson near Richmond, Virginia USA. Shadow Darner is a member of Family Aeshnidae (Darners).

Can you tell whether the exuvia is from a female or male larva? (Hint: The Related Resource, shown below, might be a helpful reference.)

Shadow Darner (Aeshna umbrosa) | exuvia (ventral)

Related Resource: Post update: Aeshna umbrosa exuvia.

Copyright © 2020 Walter Sanford. All rights reserved.

Post update: Aeshna umbrosa exuvia

Male odonates have two sets of sex organs: primary genitalia located on abdominal segment nine (S9); and secondary genitalia located on abdominal segments two-to-three (S2-3).

Closer examination of some test shots of the following Shadow Darner dragonfly (Aeshna umbrosa) exuvia, photographed on 02 December 2018, showed both sets of vestigial genitalia are clearly visible on the ventral side of this specimen.

Shadow Darner (Aeshna umbrosa) | exuvia (lateral-ventral)

Aeshna umbrosa (mating pair)

All odonates (dragonflies and damselflies) have a 10-segmented abdomen, numbered from front to back. Male dragonfly secondary genitalia, called hamules, are located in segments two and three (S2 and S3); female genitalia in segment eight (S8). Male and female dragonflies form the mating wheel in order for their genitalia to connect during copulation.

A. umbrosa (in wheel). Photo used with permission from Patrick Boez.

Related Resource: Test shots: Aeshna umbrosa exuvia.

Copyright © 2020 Walter Sanford. All rights reserved.

“Post Focus” images: Shadow Darner dragonfly

Bob Perkins collected and reared a Shadow Darner dragonfly (Aeshna umbrosa) larva/nymph. This blog post features two focus-stacked composite images of a beautifully preserved specimen of the adult that emerged from the larva.

Each composite image was created from 30 TIF files extracted from a one-second MP4 video of the subject, “photographed” using my new Panasonic Lumix DMC-FZ300 digital camera set for “Post Focus.”

Shadow Darner (Aeshna umbrosa) | dorsal view

This individual is a male, as indicated by his terminal appendages and “indented” hind wings (shown above). All male dragonflies have three terminal appendages, collectively called “claspers”: the two cerci are missing (they broke off the terminal end of the abdomen during shipping); the epiproct is intact.

Shadow Darner (Aeshna umbrosa) | dorsal-lateral view

Takeaways

Perhaps the biggest takeaway from on-going experimentation with Panasonic “Post Focus” is that the process continues to impress — it works quickly (typically one second or so) and works well, using lightweight, inexpensive equipment for making composite images of acceptable quality.

What’s not to like? The obvious answer: The image quality isn’t as high as comparable images created using HEAVY and EXPENSIVE camera gear in the controlled environment of a photo studio. On the other hand, I know from experience I’m unlikely to lug all of that gear into the field. I call it a BIG WIN to have found a relatively lightweight, inexpensive camera kit that does essentially the same job almost as well!

The next test: Use adult dragonflies in the wild as the subject. Regrettably, that will have to wait until the first odonates begin emerging during early spring.

Related Resources

• More testing: Panasonic “Post Focus”
• Testing: Panasonic “Post Focus”
• Composite image: Shadow Darner dragonfly

Tech Tips

The following equipment was used to shoot the “photos” for creation of the composite images, shown above: Panasonic Lumix DMC-FZ300 digital camera set for “Post Focus“; and two Sunpak LED-160 Video Lights.

Adobe Photoshop CC 2017 was used to create the preceding focus-stacked composite images, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

Composite image: Shadow Darner dragonfly

Bob Perkins collected and reared a Shadow Darner dragonfly (Aeshna umbrosa) larva/nymph. This blog post features a focus-stacked composite image of a beautifully preserved specimen of the adult that emerged from the larva.

This individual is a male, as indicated by his “indented” hind wings.

Shadow Darner (Aeshna umbrosa) | face-head-dorsal

Artifacts

In my experience, focus stacking either works or it doesn’t. When it doesn’t work, “artifacts” appear in the final output that can be caused by many factors. There are work-arounds that can be used to repair the artifacts with mixed success. (See Tech Tips/Related Resources.)

I shot 19 photographs that were used to create a focus-stacked composite image of the Shadow Darner dragonfly. There’s a lot going on in those photos that caused too many artifacts to publish the final output. Several of the more noticeable artifacts are shown below.

Can you see three artifacts?

Artifacts highlighted.

I created another composite image; I used as many photos as I could before the first artifacts appeared. As it turns out, only five of 19 photos were used in the do-over composite image (shown at the beginning of this blog post). Look closely — some of the same artifacts are also noticeable in the do-over version.

Related Resources

• Test shots: Shadow Darner dragonfly.
• Test shots: Aeshna umbrosa exuvia.

Tech Tips

The following equipment was used to shoot the preceding composite image: Canon EOS 5D Mark II digital camera, in manual mode; Kenko macro automatic extension tubes (12mm, 20mm, and 36mm); Canon EF100mm f/2.8L Macro lens (set for manual focus); and Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and several external flashes set for “Slave” mode including Canon 580 EX- and Canon 580EX II Speedlites and a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Auto power-off was disabled for the camera and all external flash units.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen the final output.

Tech Tips/Related Resources

• How to Focus-Stack Macro Images using Photoshop, by Don Komarechka.
• Stack it up — a guide to using the focus stacking photography technique
• Zerene Stacker Slabbing [The “Extreme Macro” Web site features lots of good resources.]

Copyright © 2019 Walter Sanford. All rights reserved.

Test shots: Shadow Darner dragonfly

Bob Perkins collected and reared a Shadow Darner dragonfly (Aeshna umbrosa) larva/nymph. This is a preserved specimen of the adult that emerged from the larva.

Test shots of this beautiful specimen were taken using a relatively small aperture of f/16 for greater depth of field. The following photo is a “one-off,” that is, not a composite image.

Shadow Darner (Aeshna umbrosa) | face-head

Related Resource: Test shots: Aeshna umbrosa exuvia.

Tech Tips

The following equipment was used to shoot the preceding photograph: Canon EOS 5D Mark II digital camera, in manual mode; Kenko macro automatic extension tubes (12mm, 20mm, and 36mm); Canon EF100mm f/2.8L Macro lens (set for manual focus); and Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and several external flashes set for “Slave” mode including Canon 580 EX- and Canon 580EX II Speedlites and a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Auto power-off was disabled for the camera and all external flash units.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

Test shots: Aeshna umbrosa exuvia

Bob Perkins collected and reared an unknown species of odonate nymph from a tiny stream in Carroll County, Virginia USA. The larva emerged from one of Bob’s holding tanks overnight on 23-24 November 2018 and metamorphosed into an adult male Shadow Darner dragonfly (Aeshna umbrosa). Shadow Darner is a member of the Family Aeshnidae (Darners). The following test shots show the exuvia from the odonate nymph.

Test shots of this beautiful specimen were taken using a relatively small aperture of f/16 for greater depth of field. Each photo is a “one-off,” that is, not a composite image. Focus stacks will be created sometime in the near future, after the exuvia is rehydrated and its legs are repositioned  for easier posing.

Lateral-ventral view

The focus point of the first photo is on the right eye. Given the orientation of the specimen, most of the exuvia is acceptably in focus at f/16. For what it’s worth, I really like the composition of this photo!

Notice the specimen has a flat labium (prementum) that doesn’t cover the face (not mask-like). That is a characteristic field mark of two families of dragonflies: Family Aeshnidae (Darners); and Family Gomphidae (Clubtails).

Shadow Darner (Aeshna umbrosa) | exuvia (lateral-ventral)

This individual is a male, as indicated by vestigial hamules that are visible on the ventral side of the specimen.

Dorsal view

The focus point of the next photo is on the head: the head is tack-sharp; the terminal appendages are in soft-focus. Sometimes it’s necessary to create focus-stacked composite images in order to render the subject in focus from head-to-tail and edge-to-edge.

Lateral spines on abdominal segments six to nine (S6-9) indicate this specimen is A. umbrosa.

Shadow Darner (Aeshna umbrosa) | exuvia (dorsal)

The focus point of the next photo is on the abdomen, just below the wing pads. Relative to the preceding photo, notice the head is slightly softer in focus while the terminal appendages are slightly sharper in focus.

Shadow Darner (Aeshna umbrosa) | exuvia (dorsal)

Related Resources

• Post update: Aeshna umbrosa exuvia.
• Odonate Exuviae – a hyperlinked list of identification guides to many species of odonate exuviae from seven families of dragonflies and three families of damselflies.

Tech Tips

The following equipment was used to shoot all of the preceding photographs: Canon EOS 5D Mark II digital camera, in manual mode; Kenko 20mm macro automatic extension tube; Canon EF100mm f/2.8L Macro lens (set for manual focus); and Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and several external flashes set for “Slave” mode including Canon 580 EX- and Canon 580EX II Speedlites and a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen all three images.

Copyright © 2018 Walter Sanford. All rights reserved.

New discoveries in 2016

The more you know, the more you know how much you don’t know. Huh? There’s always more to discover/learn! My new discoveries in 2016 are presented in reverse-chronological order.

Eastern Amberwing dragonfly exuviae

Perithemis tenera exuviae, published on 06 December 2016.

07 JUL 2016 | Potomac River | Eastern Amberwing (exuvia, head-on)

I’m a man on a mission to demystify the art and science of odonate exuviae identification. The task is as challenging as I was led to believe, but with determination and persistence it is do-able.

The specimens featured in this post are the first odonate exuviae that I was able to identify to the species level. Although the specimens were collected in early July, they were identified in early December. New species will be added to my Odonate Exuviae page when their identity is confirmed.

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Mulligan Pond at Jackson Miles Abbott Wetland Refuge (JMAWR) is a familiar location where several species, previously unknown to occur at the park, were discovered in 2016.

Shadow Darner dragonfly

Shadow Darner dragonfly (female), posted on 18 October 2016.

14 OCT 2016 | JMAWR | Shadow Darner (female heteromorph)

Russet-tipped Clubtail dragonfly

Russet-tipped Clubtail dragonfly (male), posted on 26 September 2016.

22 SEP 2016 | JMAWR | Russet-tipped Clubtail (male)

Blue-faced Meadowhawk dragonfly

Another new species discovered at JMAWR, posted on 20 September 2016.

15 SEP 2015 | JMAWR | Blue-faced Meadowhawk (female andromorph)

Lancet Clubtail dragonfly

Identifying clubtails by the calendar, posted on 30 June 2016.

26 JUN 2016 | JMAWR | Lancet Clubtail (male)

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In addition to my contributions to the odonate species list at Jackson Miles Abbott Wetland Refuge, Mike Powell discovered the first official record of Swift Setwing at JMAWR and in Fairfax County, Virginia USA.

Copyright © 2016 Walter Sanford. All rights reserved.

Shadow Darner dragonfly (female)

A Shadow Darner dragonfly (Aeshna umbrosa) was spotted during a photowalk at Mulligan Pond, Jackson Miles Abbott Wetland Refuge (JMAWR).

14 OCT 2016 | JMAWR | Shadow Darner (female heteromorph)

This individual is a mature female, as indicated by her coloration, rounded hindwings (near abdomen), and terminal appendages. Female Shadow Darners are polymorphic; this one is a female heteromorph, as indicated by her brown eyes and duller coloration than males of the same species.

14 OCT 2016 | JMAWR | Shadow Darner (female heteromorph)

The following annotated image illustrates some parts of the reproductive anatomy of a female Shadow Darner dragonfly, including an ovipositor for egg-laying and two styli (sing. stylus), structures that serve as sensors in egg positioning.

14 OCT 2016 | JMAWR | Shadow Darner (female heteromorph)

(See a full-size version of the original photo, without annotation.)

Both female and male Shadow Darners have two long, petal-like cerci (sing. cercus). Notice the female (shown above) is missing both cerci.

[Female] Cerci rounded at tip, longer than S9–10, usually broken off at maturity. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Location 4604). Princeton University Press. Kindle Edition.

In contrast, the following male has both cerci and an epiproct; the three terminal appendages are collectively called “claspers.” Claspers are used to grab and hold female damselflies during mating.

24 OCT 2014 | Huntley Meadows Park | Shadow Darner (male)

(See a full-size version of the original photo, without annotation.)

Related Resources: Scanned digital images from Western Odonata Scans in Life.

• Shadow Darner | Aeshna umbrosa | heteromorph female
• Shadow Darner | Aeshna umbrosa | heteromorph female (note very tattered wings of this old individual)
• Shadow Darner | Aeshna umbrosa | andromorph female
• Shadow Darner | Aeshna umbrosa | male (typical “A. u. umbrosa” with small green abdominal spots but nowhere near the range of that subspecies!)

Copyright © 2016 Walter Sanford. All rights reserved.

Last man standing?

It was an honor to spend Veterans Day with my good friend and photowalking buddy Major Michael Powell, U.S. Army, Retired. We were men on a mission: Searching for Great Spreadwing damselflies (Archilestes grandis), in the hope of extending the “official” late-date for this species in Virginia. Mission accomplished, but it wasn’t easy — the operation was unsuccessful until we called in an “air strike!”

Since 06 October 2015, Mike and I have been frequently monitoring the Great Spreadwing damselflies that inhabit a small permanent pond and surrounding fields at a remote location in Huntley Meadows Park.

On 11 November, Mike and I spent several hours intensively searching for our quarry; no luck. A little after 1:00 p.m., we were standing near the pond watching a lone Shadow Darner dragonfly (Aeshna umbrosa) aggressively hawking smaller odonates perching around the perimeter of the pond: the darner dipped into small hiding places in vegetation growing along the shoreline, briefly chasing odes that flew up-and-away from the relative safety of their perches. (Remember, odonates feed on flying insects.)

The Shadow Darner flushed a male Great Spreadwing from a concealed location; I happened to be standing near the spot where the damselfly landed. Talk about being in the right place at the right time!

11 NOV 2015 | Huntley Meadows Park | Great Spreadwing (male)

For a few minutes, we followed the skittish damselfly from its first perch (shown above) to two more perching places. Stop two is shown below.

11 NOV 2015 | Huntley Meadows Park | Great Spreadwing (male)

I was able to shoot only 11 photographs of this individual before he flew away. The last photo in this set is actually the last shot I took of what may turn out to be the last Great Spreadwing damselfly of 2015.

11 NOV 2015 | Huntley Meadows Park | Great Spreadwing (male)

Although we were happy to see a Great Spreadwing, it was sad when we realized the male was neither “Mr. Magoo” nor “Bendy Straw.”

Related Resource: Final fall farewell, by Mike Powell.

Copyright © 2015 Walter Sanford. All rights reserved.