Archive for the ‘How To’ Category

Dromogomphus spinosus exuvia

June 28, 2019

A dragonfly exuvia was collected by Joe Johnston on 22 May 2019 at Aquia Creek, Stafford County, Virginia USA. This specimen is the cast skin from a Black-shouldered Spinyleg (Dromogomphus spinosus) larva. D. spinosus is a member of Family Gomphidae (Clubtails).

Black-shouldered Spinyleg (Dromogomphus spinosus) | exuvia (dorsal)

At first I thought the exuvia might be a species from the genus Stylurus, based upon the mid-dorsal spine on abdominal segment nine (S9). After careful examination of two excellent photo-illustrated PowerPoint presentations by Kevin Hemeon at NymphFest 2016 (see Related Resources, below), I noticed none of the species in the genus Stylurus have dorsal hooks. That’s when I realized the specimen must be D. spinosus. Eureka!

Related Resources

The following PowerPoint presentations by Kevin Hemeon are available in the “Files” section of the Northeast Odonata Facebook group. Direct links to the documents are provided below.

The Backstory

Joe Johnston is an avid boater and sport fisherman who kindly agreed to be my “Eyes on the Aquia,” always on the lookout for odonate exuvia to share with me. On 22 May 2019 Joe caught a largemouth bass that swam around one of the wooden pilings of a boat dock that extends far into Aquia Creek. The fishing line was snagged on the piling so Joe moved his boat into position to free the fish. That’s when he noticed the exuvia clinging to a piling on the underside of the dock. Good catches, Joe!

Tech Tips

The following equipment was used to shoot the quick-and-dirty handheld macro photograph featured in this post: Fujifilm X-T1 digital camera; and Fujinon XF80mm macro lens plus lens hood. The camera was set for both manual exposure and manual focus. That’s right, a switch on the camera body is used to set the type of focus. It’s a Fujifilm thing. Actually, back-button focus was used to autofocus the image and adjusted manually as necessary. That’s also a Fujifilm thing. Camera settings: focal length 80mm (120mm, 35mm equivalent); ISO 200; f/9; 1/180s.

Godox XProF radio flash trigger, mounted on the hotshoe of my X-T1, was used to control an off-camera Godox TT685 Thinklite TTL Flash (TT685F) set for radio slave mode. The flash was fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen the image, plus add annotations.

Sometime in the future (probably the odonate “off-season”) I will create higher quality composite images of this exuvia, shown from all viewpoints including the ventral view. As it turns out, the dorsal view is sufficient to identify this species.

Copyright © 2019 Walter Sanford. All rights reserved.

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Arrowhead Spiketail dragonfly (female)

May 27, 2019

An Arrowhead Spiketail dragonfly (Cordulegaster obliqua) was spotted in a sunny clearing along a small forest stream at an undisclosed location in Prince William County, Virginia USA.

21 MAY 2019 | PNC. William County, VA | Arrowhead Spiketail (female)

This individual is a female, as indicated by her rounded hind wings, terminal appendages, and prominent ovipositor at the tip of her abdomen.

[Females in the Family Cordulegastridae (Spiketails) feature a] …pointed and spikelike (thus the group name) ovipositor, really a “pseudo-ovipositor” formed from the prolonged subgenital plate. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 7005-7006). Princeton University Press. Kindle Edition.

21 MAY 2019 | PNC. William County, VA | Arrowhead Spiketail (female)

Although the pattern of arrowhead-shaped markings visible on the dorsal side of her abdomen is unmistakeable, notice that the thorax features two stripes. The latter field mark can be used to differentiate spiketails from cruisers that have one stripe on their thorax.

21 MAY 2019 | PNC. William County, VA | Arrowhead Spiketail (female)

Mike Powell and I have photowalked together so many times that we are comfortable working cooperatively to shoot a subject. I wanted to get a shot of the face of the Arrowhead Spiketail but was concerned it would spook the dragonfly if I were to get “up in her grill.” So I waited until Mike had taken all of the photographs he wanted before approaching the dragonlfy for her “beauty shot.” As it turns out, the model was extraordinarily tolerant and didn’t fly away until sometime after Mike and I moved on to the next site.

21 MAY 2019 | PNC. William County, VA | Arrowhead Spiketail (female)

Notice the interrupted fern (Osmunda claytoniana) that appears in the background of every photo of the Arrowhead Spiketail.

Location, location, location.

Some species of odonates are habitat generalists, meaning they can be found almost anywhere there is water.

Habitat-specific odonates can be found only in specific habitats — for these species, finding them is all about location, location, location. Arrowhead Spiketail dragonflies are habitat-specialists.

Habitat: Small swift streams and soft-bottomed muddy seeps in forest, also streams reduced to series of small pools during drier weather. As in some other spiketails, skunk cabbage often present. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 7081-7082). Princeton University Press. Kindle Edition.

Skunk cabbage (Symplocarpus foetidus) and interrupted fern (Osmunda claytoniana) were observed growing in a seep located between a dirt trail and the small stream where the Arrowhead Spiketail was spotted — the perfect place for several species of habitat-specific odonates!

The last photo shows the clearing along a small forest stream where several species of dragonflies were spotted, including the Arrowhead Spiketail featured in this blog post. The stream is no more than a few feet wide and only a few inches deep in most places.

The small stream where several species of dragonflies were spotted.

The backstory

Telephoto lenses can cause a type of distortion called “foreshortening,” as seen in the preceding photo. Mike Powell and I were standing at the edge of the stream bank trying to decide whether we wanted to go down the short, steep slope to explore the clearing when we spotted a large UFO, that is, an “Unidentified Flying Odonate.” Mike and I took “record shots” of the dragonfly; looking at the LCD of our cameras, we identified the UFO as a Gray Petaltail dragonfly (Tachopteryx thoreyi).

Mike and I had seen a Gray Petaltail at another location (near the beginning of our photowalk), but we were unable to photograph it. So down the bank we went! As it turns out, there were at least two Grays in the meadow: a female; and a male. As Mike was photographing one of the Gray Petaltails he noticed another “large dragonfly.” As we slowly moved closer to the new unknown dragonfly, I quickly realized Mike had spotted an Arrowhead Clubtail. Great catch, Mike!

Please see Female Arrowhead Spiketail dragonfly for Mike’s take on our shared experience.

Uncommon

Arrowhead Spiketail is classified as an uncommon species of odonate. The following map shows all official records for Arrowhead Clubtail (C. obliqua) in the United States of America.

DSA Distribution Viewer | Arrowhead Spiketail

Source Credit: Abbott, J.C. 2006-2019. OdonataCentral: An online resource for the distribution and identification of Odonata. Available at http://www.odonatacentral.org. (Accessed: May 27, 2019).

Key: blue dots = Dot Map Project; green dots = Accepted records; yellow dots = Pending records.

Our spotting of Arrowhead Spiketail is a new DSA record for Prince William County, Virginia.

Adult flight period

According to records for the Commonwealth of Virginia maintained by Dr. Steve Roble, Staff Zoologist at the Virginia Department of Conservation and Recreation, Division of Natural Heritage, the adult flight period for C. obliqua is 11 May to 17 July. The species is classified as uncommon. Its habitat is “small streams.”

Bear in mind, Dr. Roble’s records are for the entire state, therefore the adult flight period for C. obliqua seems to be longer than it is in reality. The adult flight period for a single site is probably shorter — more likely around one month. For example, according to records for Northern Virginia maintained by Kevin Munroe, former manager of Huntley Meadows Park, the adult flight period for Arrowhead is 28 May to 27 June (peaks in June).

Copyright © 2019 Walter Sanford. All rights reserved.

 

Skimmertime, and the livin’ is easy.

May 24, 2019

Skimmers (Family Libellulidae) — like this female Spangled Skimmer dragonfly (Libellula cyanea) — remind me of “Summertime,” a classic song from the opera Porgy and Bess.

One of these mornings you’re gonna rise up singing
And you’ll spread your wings and you’ll take to the sky

This individual was spotted during a photowalk around a small pond with my good friend Mike Powell.

21 MAY 2019 | Northern Virginia | Spangled Skimmer (female)

The last two photos are similar takes on the same pose.

21 MAY 2019 | Northern Virginia | Spangled Skimmer (female)

21 MAY 2019 | Northern Virginia | Spangled Skimmer (female)

Gear talk

All of the photos featured in this blog post are uncropped JPGs, that is, full resolution for the Panasonic Lumix DMC-FZ300 superzoom bridge camera (4,000 x 3,000 pixels), published “as is” straight from the camera. I tweaked the settings for in-camera processing of JPG files and I must say I think the results look good!

It’s worth noting that I always shoot/save/edit RAW photo files. Period, full stop. I have been using JPG (Fine) plus RAW (actually, RW2) while field testing the FZ300.

Deeper dive

I recently expressed disappointment and frustration with the performance of my newer Panasonic Lumix DMC-FZ300 superzoom digital camera versus my older Panasonic Lumix DMC-FZ150. After making the switch to shooting in Manual Mode, I’m pleased to report I think I’ve found a new “set it and forget it” configuration for the FZ300.

In Manual Mode, my “walking around” settings are ISO 100, an aperture of f/4.5, and a shutter speed of 1/800 s. All of the photos in this post were shot at f/4.5.

The camera features three Custom Modes: C1; C2; and C3. C1 uses all of the “walking around” settings, except for changing the aperture to f/5.6; C2 uses an aperture of f/6.3; and C3 uses an aperture of 7.1. With the mode dial set for “C” it’s easy to switch from one custom mode to another by pressing the menu button and selecting one of the three custom settings, depending upon the desired depth of field.

An external flash unit is used in Manual mode;. The power ratio is adjusted for proper exposure, depending upon the aperture: more power is necessary with a smaller aperture (larger f-stop number); less power for a larger aperture (smaller f-stop number).

As I mentioned previously, I tweaked the settings for in-camera processing of JPG files: Photo Style = Standard; Contrast = +2; Sharpness = +2; Noise Reduction = 0; and Saturation = 0.

Noise reduction can be a good thing, but NR can soften image sharpness so it’s an adjustment I prefer to make in post-processing.

Related Resource: DMC-FZ150 versus DMC-FZ300, a blog post by Walter Sanford.

Copyright © 2019 Walter Sanford. All rights reserved.

DMC-FZ150 versus DMC-FZ300

May 8, 2019

For years, my go-to camera kit for photowalking has been the Panasonic Lumix DMC-FZ150 superzoom digital camera and a Canon 580EX Speedlite. A formula of camera and flash settings that I call “set it and forget it” works most of the time, enabling me to focus on the subject rather than futzing around with camera/flash settings.

My new Panasonic Lumix DMC-FZ300 features some significant upgrades over the DMC-FZ150 such as a touch-screen LCD, built-in WiFi (enabling remote control of the camera using the “Panasonic Image App“), 49 focus points, 4K video, and an intriguing new feature that Panasonic calls “Post Focus.”

The two cameras are similar, but as I say often, similar is not the same. As appealing as the new features of the FZ300 are, the newer camera doesn’t perform like my older FZ150. After limited testing in both the studio and in the field, I have yet to find the new formula for “set it and forget it” using the FZ300. Disappointed and frustrated, I am!

Panasonic Lumix DMC-FZ150

A Springtime Darner dragonfly (Basiaeschna janata) was spotted along Popes Head Creek at Hemlock Overlook Regional Park, Fairfax County, Virginia USA. This individual is a male.

108mm (600mm, 35mm equivalent) | ISO 100 | f/5.2 | 1/800 s | -1 ev

Flash fired, in compulsory flash mode. My external flash unit is set for Manual mode at a power ratio of 1/16, plus or minus one stop. The other settings listed in the photo caption are typical of what I call “set it and forget it,” that is, these settings work for most subjects in most lighting conditions.

The preceding photo was included in my “Top 10 Photos of 2018.” Many, if not most, of the photos in this gallery were taken using the DMC-FZ150 and my “set it and forget it” formula.

Panasonic Lumix DMC-FZ300

A Brown Spiketail dragonfly (Cordulegaster bilineata) was spotted at Occoquan Regional Park, Fairfax County, Virginia USA. This individual is a male.

108mm (600mm, 35mm equivalent) | ISO 100 | f/2.8 | 1/800 s | 1 ev

Flash fired, in compulsory flash mode.

A Common Green Darner dragonfly (Anax junius) was spotted at the North Tract of Patuxent Research Refuge, Anne Arundel County, Maryland USA. This individual is a female.

108mm (600mm, 35mm equivalent) | ISO 100 | f/2.8 | 1/800 s | 0 ev

Flash fired, in compulsory flash mode.

A Harlequin Darner dragonfly (Gomphaeschna furcillata) was spotted at the North Tract of Patuxent Research Refuge, Anne Arundel County, Maryland USA. This individual is a female.

108mm (600mm, 35mm equivalent) | ISO 100 | f/2.8 | 1/800 s | 0 ev

Flash fired, in compulsory flash mode.

What are the take-aways?

I prefer shooting in Shutter Priority mode at relatively fast shutter speeds (using the reciprocal rule) in order to reduce camera shake at longer focal lengths. If the ISO is set for 100 then the exposure triangle tells us that the only variable is aperture (f/stop). Using my “set it and forget it” formula of settings, the FZ150 typically opts for an f/stop of f/5.6 or higher (that is, a smaller lens opening); for some reason the FZ300 always seems to opt for f/2.8.

Problem is, there is too little depth of field at f/2.8! The only way I’m able to shoot serviceable photos using the FZ300 is to compose photos so the entire subject is nearly parallel to the focal plane and to sharpen the images using Adobe Photoshop.

I’m planning to start shooting in Manual mode so that I can set the ISO, aperture, and shutter speed. During limited testing in the studio, it was necessary to use a higher flash power ratio in order to get good exposure. Otherwise, Manual mode is the ultimate in “set it and forget it!”

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.

Common Green Darner (female)

May 1, 2019

A Common Green Darner dragonfly (Anax junius) was perched on a tree, approximately one-to-two feet above the ground. My good friend Mike Powell spotted this beautiful specimen while we were hunting for Harlequin Darner alongside Wildlife Loop trail at the North Tract of Patuxent Research Refuge (PRR), Laurel, Maryland USA.

This individual is a female, as indicated by her terminal appendages. Sexing Common Green Darner dragonflies is a photo-illustrated field guide that describes field marks that can be used to differentiate female and male Common Green Darners.

It’s worth noting that both photos featured in this blog post are uncropped, that is, full resolution for the Panasonic Lumix DMC-FZ300 superzoom bridge camera (4,000 x 3,000 pixels).

The following photo is one of my “record shots” for this subject. Whenever I see a dragonfly perched on a tree, I always try to refine the shot until the tree in the background fills the entire frame. If you compare/contrast the two photos, then I think you will agree with me that the composition of the first photo is much better than the second.

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.

Odonate calendars: VA Flight Dates

March 31, 2019

Google Calendar was used to synthesize “CHECKLIST OF THE DRAGONFLIES AND DAMSELFLIES OF VIRGINIA, April 2017 update” — Dr. Steve Roble’s excellent datasets for the Commonwealth of Virginia — into two calendars: Dragonflies (VA Flight Dates); and Damselflies (VA Flight Dates).

The Google Calendar default color palettes were used to color-code both calendars: Dragonflies is Graphite; and Damselflies is Birch. Individual events on each calendar are also color-coded by family.

Dragonflies

Here’s the way the dragonflies calendar looks using the Chrome Web browser on my Apple iMac desktop computer. Notice the Graphite colored vertical bar to the left of each event that indicates it belongs to the dragonflies calendar.

And here’s the way the dragonflies calendar looks using the free Google Calendar app on my Apple iPad mini 2.

Every event features the following information: common name; scientific name; early-date/late-date; abundance; and habitat.

New for 2019

An interactive version of both calendars is available online. The dragonflies calendar is shown below.

Regrettably, the color-coding is lost in the online, interactive version of both calendars. That is, unless you print the calendar.

Color-coding is also lost when the calendar is exported as an “.ics” file. That’s the bad news. The good news is the calendar can be edited after it is imported into Google Calendar and it’s easy to edit the entries to color-code them any way you like.

The colors of the rainbow (ROYGBIV) were used to color-code the seven families of dragonflies; the equivalent colors in the Google Calendar default color palette are shown in brackets.

  • R = Family Aeshnidae (Darners) [Tomato]
  • O = Family Cordulegastridae (Spiketails) [Tangerine]
  • G = Family Corduliidae (Emeralds) [Basil]
  • Y = Family Gomphidae (Clubtails) [Banana]
  • B = Family Libellulidae (Skimmers) [Peacock]
  • I = Family Macromiidae (Cruisers) [Blueberry]
  • V = Family Petaluridae (Petaltails) [Grape]

The colors for Emeralds and Clubtails were flip-flopped because it just makes sense the Emeralds should be color-coded green!

Damselflies

Here’s the way the damselflies calendar looks using the free Google Calendar app on my Apple iPad mini 2.

Like the dragonflies calendar, every event features the following information: common name; scientific name; early-date/late-date; abundance; and habitat.

“FSL” was used to color-code the three families of damselflies common to the mid-Atlantic states (USA); the equivalent colors in the Google Calendar default color palette are shown in brackets.

  • F – Family Calopterygidae (Broad-winged Damselflies) [Flamingo (formerly Tomato)]
  • S – Family Coenagrionidae (Narrow-winged Damselflies) [Sage (formerly Peacock)]
  • L – Family Lestidae (Spreadwings) [Lavendar (formerly Basil)]

For what it’s worth, all of the colors for the damselflies calendar are pastel shades.

New for 2019

An interactive version of the damselflies calendars is available online, as shown below.

Dragonflies and Damselflies

The damselflies calendar was updated for 2019 so that no colors are duplicated from the dragonflies calendar. This should help to eliminate confusion when both calendars are displayed at the same time, as shown below.

Lessons Learned

As I worked on the calendar, patterns began to emerge that I hadn’t noticed before. For example, it’s clear that the serious odonate hunter needs to hit the ground running as soon as early March. Remember that Dr. Roble’s dataset is for the entire state. You may not see a given species on its early-date, but it could be seen on that date and certainly can’t be seen if you don’t look!

Tech Tips

Download the “.ics” file from the Virginia Odonata Facebook group. Launch Google Calendar on a desktop computer. Create a new calendar by clicking on the three vertical dots to the right of “Add calendar” and selecting “Create new calendar”; give the calendar a name such as “Test Calendar” and click on the “Create calendar” button. (You can change the name later.) “Test Calendar” should appear in the list of calendars under “My calendars.”

Mouse-over the name “Test Calendar” and click on the vertical column of three dots, labeled “Options for Test Calendar” then select “Settings and sharing.” In the upper-left sidebar, click on “Import and export”; select the “.ics” file to import and select “Test Calendar” from the drop-down menu labeled “Add to calendar.” There are 143 events in the Dragonflies calendar; 56 events in the Damselflies calendar.

If you decide to color-code individual events like I did, click on an event then click on the pencil icon labeled “Edit event.” Select a color and click the “Save” button, then click the radio button for “All events.” Beware: You can right-click on an individual event and change its color but DON’T GO THERE! That results in an event that doesn’t occur annually using the new color you chose.

Related Resources

Kevin Munroe, former manager of Huntley Meadows Park, created an excellent calendar called Dragonflies of Northern Virginia – Flight Periods. This calendar is a valuable resource for hunting dragonflies in Northern Virginia. I think the value of Kevin Munroe’s calendar is enhanced by using it in combination with my visualization of Steve Roble’s dataset.

Dragonflies & Damselflies of Loudoun County features a flight calendar for dragonflies and damselflies.

Copyright © 2019 Walter Sanford. All rights reserved.

Aging gracefully

March 1, 2019

The following gallery features several photos of a Valentines Day gift of appreciation from The Beacon of Groveton. A little more than two weeks after the red rose was delivered, the flower appears to be aging gracefully.

I experimented with a different lighting setup than the last photo shoot of this flower. An articulating Loc-line arm was used to hold and pose the cut flower. The background is a 12″ x 12″ piece of white plastic, mounted vertically and backlighted by a radio-controlled external flash unit. Notice the vignetting on the left side of the photo, caused by the flower being offset from the center of the sweet spot of the backlight.

28 FEB 2019 | BoG Photo Studio | Valentines Day rose

The simplest solution to the vignetting problem is to crop the image. Ah, much better, and much closer to achieving my vision for the finished product — the red rose posed against a clean white background!

28 FEB 2019 | BoG Photo Studio | Valentines Day rose

The next photo is the only photo in the set that turned out exactly as I wanted. Well, the flash in Group B (off camera, to the front-left of the subject) is a little too bright, but that’s just the perfectionist in me talking.

28 FEB 2019 | BoG Photo Studio | Valentines Day rose

The first two photos were taken at f/8. I moved the camera closer to the subject for the last photo and switched to f/11 for more depth of field. The shadow of the flower stem on the white background wasn’t part of my plan — I’m not sure whether it adds to the photo or detracts. What do you think?

28 FEB 2019 | BoG Photo Studio | Valentines Day rose

Tech Tips

The following equipment (shown below) was used to shoot the preceding photos: Fujifilm X-T1 digital camera; Fujifilm MCEX-16 extension tube (for some photos, but not all); Fujinon XF80mm macro lensGodox XProF TTL Wireless Flash Trigger for Fujifilm cameras; a Godox TT685F Thinklite TTL Flash for Fujifilm Cameras; a Godox TT685C Thinklite TTL Flash for Canon Cameras fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier; and a Godox TT685O Thinklite Flash for Olympus/Panasonic Cameras. All three flashes were set for radio-controlled slave mode, in Manual Mode.

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

Copyright © 2019 Walter Sanford. All rights reserved.

Composite image: “Generic Gomphid” (face)

February 27, 2019

larva/nymph in the Family Gomphidae (Clubtails) was collected by Bob Perkins from the New River in southwestern Virginia. The larva died before it metamorphosed into an adult.

“Generic Gomphid” larva (preserved specimen) | New River, VA USA

An Ashy Clubtail dragonfly nymph was also collected by Bob Perkins. (The date and location where the specimen was collected are unknown.) The nymph was reared in captivity until it emerged on 21 March 2017 and metamorphosed into an adult female. This specimen is the exuvia from the nymph.

Although face-head of the “Generic Gomphid” and Ashy Clubtail look similar, they aren’t identical. More later after the specimen is keyed out carefully.

Related Resources

Tech Tips

13 photos were used to create the focus stack of the “Generic Gomphid.” A single focus point was positioned over select anatomical features; photos were taken at each point of interest.

The following equipment was used to shoot the composite image of the “Generic Gomphid”: Canon EOS 5D Mark II digital camera, in manual mode; Canon MP-E 65mm Macro lens (set for f/11 at ~2.5x); a Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and a single external flash set for “Slave” mode — 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 external flash units.

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

Copyright © 2019 Walter Sanford. All rights reserved.

Cordulegaster sp. larva (dorsal view)

February 25, 2019

This post features a focus-stacked composite image that shows a dorsal view of an odonate larva/nymph from the Family Cordulegastridae (Spiketails) that was collected and reared by Bob Perkins. The larva died before it metamorphosed into an adult.

Cordulegaster sp. larva (female) | dorsal view

Most larvae go through 10-13 stages of development known as “instars.” The author lacks sufficient experience to identify the instar of this specimen, although it appears to be one of the later stages as indicated by its well-developed wing pads.

Related Resources

Tech Tips

12 photos were used to create the focus stack. A single focus point was positioned over select anatomical features; photos were taken at each point of interest.

The following equipment was used to shoot all of the photographs for the focus-stacked composite image, shown above: Canon EOS 5D Mark II digital camera, in manual mode; Kenko 20mm macro automatic extension tubeCanon 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 create the focus-stacked composite image, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

Cordulegaster sp. larva (ventral view)

February 22, 2019

Bob Perkins collected and reared an odonate larva/nymph from the Family Cordulegastridae (Spiketails). The larva died before it metamorphosed into an adult.

This post features a focus-stacked composite image that shows a ventral view of the preserved larva; a composite image showing the dorsal view will be published in my next blog post.

Cordulegaster sp. larva (female) | ventral view

This individual is a female, as indicated by her rudimentary ovipositor that can be seen on the ventral side of the specimen along the boundary between abdominal segments eight and nine (S8-9). Do you see it?

Related Resources

Tech Tips

Nine (9) photos were used to create the focus stack. A single focus point was positioned over select anatomical features; photos were taken at each point of interest.

The following equipment was used to shoot all of the photographs for the focus-stacked composite image, shown above: Canon EOS 5D Mark II digital camera, in manual mode; Kenko 20mm macro automatic extension tubeCanon 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 create the focus-stacked composite image, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.


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