Uhler’s Sundragon dragonfly (female)

April 20, 2021

Uhler’s Sundragon (Helocordulia uhleri) was spotted during a recent photowalk along a mid-size stream at an undisclosed location in Prince William County, Virginia USA.

13 APR 2021 | Prince William County, VA | Uhler’s Sundragon (female)

This individual is a female, as indicated by her rounded hind wings and terminal appendages. All female dragonflies have a pair of cerci (superior appendages) that have little or no function. Both the rounded hind wings and two cerci are visible clearly in the full-size version of the following photo.

13 APR 2021 | Prince William County, VA | Uhler’s Sundragon (female)

Just the facts, ma’am.

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 H. uhleri is 29 March to 27 June. The species is classified as common. Its habitat is “streams.”

Bear in mind, Dr. Roble’s records are for the entire state, therefore the adult flight period for H. uhleri seems to be longer than it is in reality. The adult flight period for a single site is probably no more than a month, and more likely around two-to-three weeks. For example, according to records for Northern Virginia maintained by Kevin Munroe, former manager of Huntley Meadows Park, the adult flight period for Uhler’s is 11 April to 05 May.

It’s also worth noting that the window of opportunity to see Uhler’s Sundragon closes rapidly after trees are in full leaf; this phenological event usually occurs by mid-April in the mid-Atlantic USA.

Is Uhler’s Sundragon common? I guess the answer to that question depends upon where you live. In Northern Virginia, Kevin Munroe classified H. uhleri as “rare.” In fact, I’m aware of only one location in Northern Virginia where Uhler’s Sundragon can be found with reasonable certainty although not in large numbers.

Copyright © 2021 Walter Sanford. All rights reserved.

Selys’s Sundragon dragonfly (male)

April 16, 2021

I discovered a Selys’ Sundragon dragonfly (Helocordulia selysii) during a recent photowalk with Michael Powell at an undisclosed location in Prince William County, Virginia USA. Selys’s Sundragon is a new species for my Life List of odonates and for Prince William County, VA. [Odonata Species (p. 1 of 2) — current as of 14 April 2021 — shows part of the species list for Prince William County before Selys’s was added.]

This individual is a male with a malformed abdomen. Notice his abdomen is twisted so that the terminal appendages aren’t in their usual alignment. The cerci should be on top and the epiproct should be on the bottom; they aren’t where they should be.

13 APR 2021 | Prince William County, VA | Selys’s Sundragon (male)

All male dragonflies have three terminal appendages, collectively called “claspers,” that are used to grab and hold female dragonflies during mating. Male dragonfly terminal appendages don’t look exactly the same for all species of dragonflies, but their function is identical. The misalignment of this Selys’s terminal appendages might be a problem when attempting to form the “wheel position” with females.

The Backstory

Mike Powell and I were men on a mission to photograph Uhler’s Sundragon dragonflies (Helocordulia uhleri). The sky was completely overcast when we arrived at our destination. According to the weather forecast, the sky was supposed to clear around 1:00 pm, and sure enough it did. Soon afterward, we spotted our first Uhler’s of the day and spent some time photographing several individuals.

All of the Uhler’s we saw were female. At some point I said to Mike (paraphrasing) “I need to photograph at least one male before we leave!” I walked a little farther downstream from a place where Mike was shooting macro photos of a very cooperative female Uhler’s. That’s when I spotted the male shown in the preceding photo.

My first impression was the dragonfly seemed to be noticeably smaller than the female Uhler’s we had been photographing. Turns out I was right! According to Dragonflies and Damselflies of the East by Dennis Paulson, Uhler’s are 41-46 mm in total length (4.1-4.6 cm) and Selys’s are 38-41 mm in total length (3.8-4.1 cm). For those of you keeping score at home, that’s only ~1.5″ long — small for many if not most dragonflies!

Related Resource: Selys’s Sundragon dragonfly – a blog post by Michael Powell, my good friend and photowalking buddy.

Copyright © 2021 Walter Sanford. All rights reserved.

Tethered

April 13, 2021

“Tethered.” What does that word mean to a photographer? In its simplest sense, it’s when a camera is connected to a computer either by some type of cable or sometimes wirelessly.

“Tethered shooting” implies the photographer is able to control the camera remotely, either partially or completely.

Is there really a distinction between the two terms? I think so.

In my last two blog posts I mentioned that my older Fujifilm X-T1 mirrorless digital camera cannot be used for tethered shooting using either the free Fujifilm X Acquire 2 software or via some sort of HDMI Video Capture device. That being said, the Fujifilm X-T1 camera can be tethered to my computer in order to display the output from the HDMI port on the camera.

The section entitled “Viewing Pictures on TV” that appears on p. 108 of the Fujifilm X-T1 Owner’s Manual is shown below.

When the Fujifilm X-T1 is connected to my Apple MacBook Air computer via a MavisLink Video Capture Card and displayed on-screen using OBS Studio, the camera thinks the computer is a TV. Well, sort of.

OBS Studio | Properties for ‘Video Capture Device’

First, add a “Video Capture Device” to a “Scene” in OBS Studio. Select “USB Video” since the “HDMI Video Capture” device connects to the computer via USB. A colorful test pattern appears on screen, even when the camera is turned on.

When the “Play” button on the back of Fujifilm X-T1 camera is pressed, a small green LED in the upper-right corner of the camera turns on and the photos saved to the memory card in your camera are shown on-screen, one image at a time. Use the “D” pad on the back of the camera to cycle through all of the photos on the memory card. Press the “Play” button when you’re finished and the test pattern reappears in OBS Studio.

By the way, the photo shown in the preceding “Screenshot” of OBS Studio is one of the images I shot for Sumo Citrus still life, a recent blog post.

Copyright © 2021 Walter Sanford. All rights reserved.

What is it?

April 6, 2021

Ladies and gentlemen, children of all ages. It’s time for another exciting episode of “What is it?”

This episode is a little different because the name of the mystery item is printed clearly on the product itself. I guess the real mystery is two-fold: What does the acronym “HDMI” mean, and what does this video capture device do?

“HDMI” stands for “High-Definition Multimedia Interface.” The MavisLink Video Capture Card converts HDMI 4K 60FPS (from your digital camera) to USB 1080P 60FPS (on your computer) that can be either recorded or live streamed on video conferencing services.

“MavisLink” is a brand name that was recommended by Graham Houghton, a gentleman whose expertise I respect and opinion I value. It’s worth noting a quick Web search will reveal lots of video capture cards sold under different brand names that look identical to the MavisLink device shown above. Do they work as well as the one recommended by Graham? Who knows?

I plan to use the device in combination with Open Broadcaster Software (OBS Studio) to record the video and audio output from some of my digital cameras; the saved video clips will be featured in future “how to” blog posts.

So far I have tested the process with several of my cameras: My Panasonic Lumix DMC-FZ300 and Fujifilm X-T3 work; my Fujifim X-T1 doesn’t work.

I still need to test my older Canon EOS 5D Mark II. It should work but as far as I know the camera doesn’t feature “clean HDMI” output, that is, some or all of the info display on the camera viewfinder/LCD (e.g., the focus rectangle) is included in the output.

Related Resource: DSLR and Mirrorless Webcams Versus Capture over HDMI, by Graham Houghton (8:56). See the segment entitled “HDMI Capture” that begins at ~5:01 into the video.

Copyright © 2021 Walter Sanford. All rights reserved.

Fujifilm X Webcam 2

March 30, 2021

Fujifilm X Webcam 2 is a free software application that enables the use of select Fujifilm cameras as a device for video conferencing, live video streaming, etc. Versions of the software are available for both macOS and Windows.

X Webcam is compatible with my Fujifilm X-T3 mirrorless digital camera; it isn’t compatible with my Fujifilm X-T1. An older camera — one that is used less than the newer model — would be perfect to repurpose as a Webcam. <Heavy sigh!>

How it works (when it looks like it doesn’t).

Connect the camera to a computer via a USB cable. A small green LED on the back of my Fujifilm X-T3 indicates the camera/computer connection is active. Next launch Fujifilm X Webcam 2 on your computer. Notice the window that appears on-screen is grayed-out, suggesting the application isn’t working. But it is!

In order to look like it’s working, Fujifilm X Webcam 2 must be connected to some sort of videoconferencing application such as Google Meet, Open Broadcaster Software (OBS Studio), Zoom, etc.

Nothing happened after I started OBS Studio, that is, until a “Video Capture Device” was added. At that point, the X Webcam 2 window was active. Notice my camera was recognized by X Webcam 2, as indicated by the following Screencapture.

The bigger picture shows both Fujifilm X Webcam 2 and OBS Studio are working. My X-T3 digital camera is listed as “Video Capture Device” in the OBS “Sources” panel. The audio output from the built-in microphone on my laptop computer is shown in the OBS “Audio Mixer” panel. (Audio isn’t included in the feed from X Webcam 2.)

At this point, OBS Studio could be used to either stream or record the output from my X-T3 and laptop microphone. More “Sources” can be added to the main window, but for the purpose of this blog post all I wanted to do is demonstrate that Fujifilm X Webcam 2 can be interfaced with OBS Studio via a USB cable.

Related Resources

Copyright © 2021 Walter Sanford. All rights reserved.

Post update: Tachopteryx thoreyi exuvia

March 26, 2021

I just updated an older blog post in order to correct a label for an anatomical structure that was mislabeled, plus I added some new information.

The updated annotated image is shown below.

No. 2 | Gray Petaltail (Tachopteryx thoreyi) | exuvia (dorsal)

While I was editing the photo, I noticed something I hadn’t seen before — a large dorsal hook of abdominal segment nine (S9) that overhangs segment 10 (S10). This time I’m fairly sure the structure is correctly called a dorsal hook.

Related Resource: Tachopteryx thoreyi exuvia, an updated version of a blog post by Walter Sanford.

Copyright © 2021 Walter Sanford. All rights reserved.

Sumo Citrus still life

March 19, 2021

Have you seen/eaten Sumo Citrus? They’re easy to peel, seedless, and billed as “the sweetest orange.” Delicious, I say!

How I got the shots

I set up a tripod at a good distance from the subject for a 50mm lens. Then I switched cameras without moving the tripod. Each camera/lens combo was set for an aperture of f/8; other camera and flash settings varied as necessary. (See EXIF info for details regarding camera settings for each photo.)

Canon 5D Mark II

Canon EF 50mm f/1.8 II lens (“Nifty 50”), Godox X2TC, Godox TT685C plus Lastolite flash modifier.

18 March 2021 | BoG Photo Studio | Sumo Citrus

Fujifilm X-T1

Fujinon 18-55mm zoom kit lens set for 34mm (51mm, 35mm equivalent), Godox XProF, Godox TT685C plus Lastolite flash modifier.

18 March 2021 | BoG Photo Studio | Sumo Citrus

Fujifilm X-T3

Fujifilm 11mm extension tube, Fujinon XF80mm macro lens, Vello Off-Camera TTL Flash Cord, Godox X2TF, Godox TT685C plus Lastolite flash modifier.

18 March 2021 | BoG Photo Studio | Sumo Citrus

Sumo Citrus from Giant Food

Bernard Nimmons is the produce manager at the Giant Food located in Beacon Center. I sent a Facebook Messenger message to Bernard recently…

I need Sumo Oranges STAT! Are they back in stock?

The following selfie photo is Bernard’s reply to my message. Now you can see why I always say “Bernard puts the ‘Pro’ in Produce.”

Selfie photo used with permission from Bernard Nimmons.

Copyright © 2021 Walter Sanford. All rights reserved.

Odonate calendars updated for 2021

March 16, 2021

Google Calendar was used to synthesize Dr. Steve Roble’s excellent datasets for the Commonwealth of Virginia into two calendars: Dragonflies (VA Flight Dates); and Damselflies (VA Flight Dates). An online, interactive version of both calendars is provided on this page.

Dragonflies (VA Flight Dates) – Updated for 2021

The dragonflies calendar is shown below. Every event features the following information: common name; scientific name; early-date/late-date; abundance; and habitat.

Damselflies (VA Flight Dates) – Updated for 2021

An interactive version of the damselflies calendar is also available online, as shown below. Every event features the following information: common name; scientific name; early-date/late-date; abundance; and habitat.

Color-coded versions

Both calendars are color-coded by family. Regrettably, the color-coding is lost in the online, interactive version of both calendars. That is, unless you print the .ics version of the calendars (samples shown below). Please contact me if you would to have copies of the .ics versions of the calendars.

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

  • 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]

Dragonflies (VA Flight Dates) – March 2021

“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]
  • S – Family Coenagrionidae (Narrow-winged Damselflies) [Sage]
  • L – Family Lestidae (Spreadwings) [Lavendar]

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

Damselflies (VA Flight Dates) – March 2021

Related Resources

CHECKLIST OF THE DRAGONFLIES AND DAMSELFLIES OF VIRGINIA, April 2017 and April 2020 updates” by Dr. Steve Roble, Staff Zoologist at the Virginia Department of Conservation and Recreation, Division of Natural Heritage.

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 Dr. Steve Roble’s dataset.

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

Copyright © 2021 Walter Sanford. All rights reserved.

Answer key: Vernier calipers

March 12, 2021

The jaws of the caliper are spread apart 11.15 mm (7/16″), as shown by the following annotated photo.

08 MAR 2021 | Bog Photo Studio | analog Vernier caliper (close-up)

As it turns out, I used the calipers to measure the diameter of the barrel of a brass spigot used for photography clamps.

Product image courtesy B&H Photo.

Related Resource: Tools of the trade: Vernier calipers.

Copyright © 2021 Walter Sanford. All rights reserved.

Tools of the trade: Vernier calipers

March 9, 2021

A Vernier caliper is a useful tool for measuring things precisely. The caliper shown in the following photos is precise to 0.05 mm (1/128 in).

08 MAR 2021 | Bog Photo Studio | analog Vernier caliper

Some guides to the identification of odonate larvae and exuviae are measurement intensive. A caliper can be helpful for making measurements of a specimen quickly.

08 MAR 2021 | Bog Photo Studio | analog Vernier caliper (close-up)

Carolina Biological Supply Company sells both analog and digital calipers. Analog calipers are relatively inexpensive and work well. Digital calipers can cost at least five times more than their analog counterparts.

Carolina sells two models of analog Vernier calipers: one model is made of nickel-plated steel; the other is made of plastic. The metal caliper has sharp edges and points that can scratch surfaces easily; the plastic caliper won’t scratch most surfaces.

The metal model comes in a plastic pouch; the plastic model doesn’t. Advantage metal model, right? No! Both the metal caliper and its plastic pouch are covered in some type of lubricant that is both unnecessary and a chore to clean off the caliper. Can you tell I prefer the plastic model?

Learning by doing – How to read the Vernier scale

How to Read a Metric Vernier Caliper by WeldNotes.com (7:01) is an animated video that explains how to read the Vernier scale of an analog caliper. Watch the video, then test yourself to see whether you can determine how far the bigger jaws of the caliper are spread apart (in mm), as shown in the preceding close-up photo.

Be careful — the Vernier scale shown in the video is precise to 0.02 mm while the one shown in the photograph is precise to 0.05 mm. Here’s a hint: The jaws of the caliper are slightly more than 11 mm apart.

Please submit your answer as a comment on this blog post. Relax, you won’t see any spoilers because all comments must be approved by the blog administrator. (Hey, that’s me!)

Post update

The answer key for the caliper quiz is now online.

Copyright © 2021 Walter Sanford. All rights reserved.

 


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