Archive for the ‘digital videography’ Category

Odonate exuviae collecting sites

July 29, 2019

The following video shows a “boater’s-eye view” of some sites where odonate exuviae have been collected by Joseph Johnston along Aquia Creek, located in Stafford County, Virginia USA. Joe 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.

The first photo gallery features still images of several spots shown in the preceding video. Joe estimates the water is ~5-6 feet deep outside the channel markers, and much deeper in the middle of the creek.

Joe’s boat is somewhere between the long boat docks (lower-right quadrant) and Government Island (near center), as shown in an aerial view of Aquia Creek provided by Google Maps.

The last photo gallery features still images of several exuviae, shown in situ before Joe collected the specimens. The first photo shows where it all began, when Joe collected his first dragonfly exuvia for me on 20 June 2018.

Related Resources

Credits

All media Copyright © 2019 by Joseph Johnston. Used with permission from Mr. Johnston.

Copyright © 2019 Walter Sanford. All rights reserved.

Advertisements

“Post Focus” image: toy dinosaur

February 8, 2019

A toy dinosaur was “photographed” at BoG Photo Studio using my new Panasonic Lumix DMC-FZ300 digital camera set for “Post Focus.”

The camera was set for ISO 100 and Aperture Priority at f/2.8. Two Sunpak LED-160 Video Lights plus a Nissin i40 external flash unit (set for video light) were used to light the scene. 30 individual frames were extracted from the resulting MP4 video, and saved as TIF files; Adobe Photoshop was used to create the following focus-stacked composite image.

A plastic toy dinosaur.

Noise (graininess) has been a problem in some previous test shots using “Post Focus,” due to low light (underexposure). I changed the ISO from AUTO to 100 for this test, opened the aperture all the way to f/2.8, and added a third LED light source.

This is the first time I tested “Post Focus” and felt like the camera had a mind of its own! Nonetheless, the final output turned out OK. Further research and experimentation is required in order to understand what happened and why.

Copyright © 2019 Walter Sanford. All rights reserved.

“Post Focus” images: Shadow Darner dragonfly

January 30, 2019

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.”

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

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.

More testing: Panasonic “Post Focus”

January 28, 2019

A toy dragonfly was “photographed” at BoG Photo Studio using my new Panasonic Lumix DMC-FZ300 digital camera set for “Post Focus.” Two Sunpak LED-160 Video Lights were used to light the scene. 30 individual frames were extracted from the resulting MP4 video, and saved as TIF files; Adobe Photoshop was used to create the following focus-stacked composite image.

A plastic toy dragonfly.

The test shots featured in my last blog post, and this one, were taken in order to establish the proof of concept that Panasonic “Post Focus” can be used to quickly (well, everything is relative) create high quality focus-stacked composite images. After limited testing, I can say the process works fairly well.

The next test: Use a preserved specimen of a real adult dragonfly as the subject. Please stay tuned for my next blog post.

Copyright © 2019 Walter Sanford. All rights reserved.

Testing: Panasonic “Post Focus”

January 25, 2019

My new Panasonic Lumix DMC-FZ300 features some significant upgrades over my 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, and 4K video, to name a few. Perhaps the most intriguing new feature is what Panasonic calls “Post Focus.”

“Post Focus” can be used to change the focus point after a photograph is taken, in camera. OK, that’s astounding! But wait, there’s more.

With “Post Focus” enabled, the camera is used in the same way as when you’re shooting still photos. In reality, the camera records a small movie clip in 4K video at 30 fps (4:3 aspect ratio) every time you press the shutter button.

The 4K movie recording function is used to record roughly one second of MP4 video at 30 frames/second. During this recording, the camera’s autofocusing system scans the lens around the subject, moving from the foreground to the background to cover the entire scene. … It’s like a sophisticated form of focus bracketing and produces a movie clip containing about 30 frames. Source Credit: How the Panasonic Post Focus function works.

One reviewer of photography gear opined the process is too slow to be useful in real-world situations; in contrast, my first impression is the process works surprisingly quickly.

An MP4 file can be opened in Adobe Photoshop in order to export individual frames from the 4K video clip; the files can be saved in either JPG or TIF format. In turn those files can be imported into Photoshop to create a focus-stacked composite image, such as the one shown below.

A plastic toy Pterodactyl, 6.5″ in width.

A toy Pterodactyl was “photographed” at BoG Photo Studio using Panasonic “Post Focus.” One Sunpak LED-160 Video Light was used to light the scene. 30 individual frames were extracted from the resulting MP4 video, and saved as TIF files; Adobe Photoshop was used to create the preceding focus-stacked composite image.

I think Panasonic “Post Focus” shows great potential for enabling the production of high quality focus-stacked composite images when photowalking, without carrying a lot of photography gear into the field.

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.

Burst mode flash photography

October 12, 2018

This post provides a brief demonstration of burst mode flash photography using the gear shown in the following photo: Fujifilm X-T1 digital camera plus Fujifilm MCEX-11 extension tube and Fujinon XF80mm macro lensGodox XProF radio flash triggerGodox TT685F external flashGodox PROPAC PB960 Lithium-Ion Flash Power Pack; and Quantum Instruments CZ2 Power Cable (for Turbo Series Power Packs).

Godox flash photography gear.

The Fujifilm X-T1 digital camera is set for “CL” (continuous low) burst mode. The Godox TT685F external flash unit is set for Manual mode at 1/128 power, as shown on the LCD of the Godox XProF radio flash trigger mounted on the camera hot shoe. The external flash unit is connected to a Godox PROPAC PB960 power pack using a Quantum Instruments cable.

The external flash unit is powered by a set of four AA batteries, as usual. The external power pack enables a much faster recycle rate for the flash than is possible using only AA batteries.

The Quantum Instruments CZ2 Power Cable fits Canon external flash units such as the Canon MT-26EX-RT Macro Twin Lite and Canon 580EX- and Canon 580EX II Speedlites, as well as Godox external flash units made for Canon, Fujifilm, and Olympus/Panasonic digital cameras. You may want to buy two cables, since the Godox PROPAC PB860 can power two flash units at once.

Related Resources

Copyright © 2018 Walter Sanford. All rights reserved.

Habitat for Tiger Spiketail dragonfly

August 9, 2018

In the world of odonates, there are habitat generalists and habitat specialists. Tiger Spiketail dragonfly (Cordulegaster erronea) is a habitat specialist.

Habitat: Small forest streams and seeps, often with skunk cabbage and interrupted fern. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 7028-7029). Princeton University Press. Kindle Edition.

The following video shows ideal habitat for C. erronea: A clean, seep-fed small stream in the forest.

The black rock in the middle of the creek is approximately five feet (~5′) from the place in the stream channel where I was sitting on a Coleman camp stool. The video begins with me looking at a seep that feeds the stream; then I pan left, right, and back to center stage.

Tech Tips: The preceding movie looks better viewed in full-screen mode. The video was recorded in 1080p at 60 fps using a head-mounted GoPro Hero4 Black action camera. The camera was positioned so that it recorded what I saw when looking straight ahead; the scene changed by moving my head. 60 fps was used so that I could edit the video to show smooth slow-motion video of Tiger Spiketail dragonflies in flight. I think one of the bigger take-aways is a Tiger fly-by would have been recorded clearly enough to be able to identify the species. For what it’s worth, the closest focusing distance of the GoPro Hero4 Black is approximately 12 inches (~1′).

GoPro CapCam©

A GoPro QuickClip was used to mount an action camera on the bill of a baseball cap.

GoPro Hero4 Black action camera, plus QuickClip mount.

The GoPro Head Strap + QuickClip is compatible with all GoPro cameras and sells for $19.95 retail.

GoPro Hero4 Black action camera, plus QuickClip mount.

The Backstory

I visited the location shown in the video three times: Several Tiger Spiketail dragonflies were observed at the site on 19- and 26 July 2018; no Tiger Spiketails were spotted on 06 August 2018, the day the video was recorded. It’s worth noting that the adult flight period for C. erronea peaks in July in Northern Virginia (USA). Most of the window of opportunity was missed due to near record setting rainfall for the month of July, including a period of seven consecutive days of rain totaling nearly 10 inches!

Although I saw several Tiger Spiketail dragonflies, every individual was in flight and I was unable to shoot still photos and/or video — they were gone by the time I reached for my camera! The GoPro CapCam© is my solution to this problem.

An Apple iPad mini is used to remotely control the action camera using the GoPro app (formerly known as “Capture”) via Bluetooth. Among many features, the app provides real-time display of the camera field of view. The camera is positioned correctly on the bill of my cap by holding the iPad directly in my line of sight and adjusting the camera mount so the iPad is shown in the middle of the screen, against the background.

Copyright © 2018 Walter Sanford. All rights reserved.

Mocha Emerald terminal appendages (female)

September 29, 2017

Mocha Emerald dragonfly (Somatochlora linearis) was spotted by Andrew Rapp in Henrico County, Virginia USA. This individual is a female.

Terminal appendages

All female dragonflies have a pair of cerci (superior appendages) that have little or no function. The hind wings of female Mocha Emerald dragonflies are rounded.

21 JUL 2017 | Henrico County, VA | Mocha Emerald (female)

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

21 JUL 2017 | Henrico County, VA | Mocha Emerald (female)

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

Notice the subgenital plate shown in the preceding photo.

subgenital plate: plate below S8 that holds bunches of eggs when enlarged; variable enough in shape to be of value in identification. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 11723-11724). Princeton University Press. Kindle Edition.

“S8” refers to abdominal segment eight. Remember that all dragonflies and damselflies have a 10-segmented abdomen, numbered from front to back.

Oviposition (egg-laying)

The following Apple iPhone 3GS “raw” video clip shows a female Mocha Emerald dragonfly laying eggs by the process of oviposition. The process typically lasts a few seconds to a few minutes. This individual was spotted on 16 July 2011 during a photowalk through the “Wildlife Sanctuary,” one of seven small parks in the community of Hollin Hills, Fairfax County, Virginia USA.

Mocha Emerald dragonfly (female, ovipositing) [Ver. 2] (0:23)

Related Resource: Mocha Emerald terminal appendages (male).

Editor’s Note: Sincere thanks to Andrew Rapp for permission to use his still photographs.

Copyright © 2017 Walter Sanford. All rights reserved.

More focus stacking with CamRanger

April 10, 2017

When I started experimenting with completely automated focus stacking using CamRanger, I couldn’t tell what, if anything, was happening. In fact, I wasn’t sure the process was working as advertised. So I devised a plan to photograph a simple subject (a six-inch ruler in this case) and use “focus peaking” to track what happened. By the way, it’s worth noting that my Canon EOS 5D Mark II DSLR camera doesn’t feature focus peaking, but the CamRanger app does!

During initial testing, I shot several small focus stacks. The following screen capture shows the display on my iPad mini (with retina display) running the CamRanger app; the focal plane of the lens is highlighted by red focus peaking.

Here’s a screen capture from another test, showing the final location of the focal plane (highlighted in red).

I made a movie that demonstrates what happens when CamRanger creates a focus stack. It was fun to watch the focal plane advance along the ruler as CamRanger captured the shots automatically!

The movie begins with a small focus stack using a “Large” step size (the largest increment of three options). When focus stacking is active, notice that most of the screen is covered by a translucent gray layer that prevents the user from changing settings accidentally. I cancelled the focus stack after two shots. Next I changed the step size to “Medium” and started a new stack. Notice that the focal plane of the lens begins where the last focus stack ended. The new step size is noticeably smaller.

Automated focus stacking using CamRanger (2:12)

As shown in the right side bar of the CamRanger app, I set the camera to shoot RAW plus small JPG. Both file types are recorded on the memory card in the camera; thumbnail versions of the JPG files are displayed at the top of the iPad screen. Although I usually shoot RAW only, JPG files can be transferred via WiFi faster than RAW files!

I set the CamRanger app to wait 10 seconds between shots, in order to allow adequate time for the camera to write the image files to the memory card, transfer the JPG thumbnail from the camera to the app, rack the lens to the next focal plane, and for the external flash units to power cycle.

My first finished automated focus stacks

I created a 30-layer focus stack using a medium increment. The following photo shows the JPG version of the first layer.

I used Adobe Photoshop CC 2017 to create a medium-increment focus stack using the small JPGs because they can be processed faster than RAW. The resulting composite image is shown below.

Finally, here’s the resulting composite image of a five-layer focus stack created from large increment/medium JPG photos. In my opinion, the output looks almost as good as the composite image created from five times as many layers.

Lessons Learned

  • Given a choice, run the CamRanger app on the most powerful tablet you own. I use my iPad mini rather than iPad 3 (with retina display). Although the iPad 3 screen is larger than the iPad mini, it features a slower processor. That being said, the iPad 3 is perfectly suitable for using the CamRanger app for other less processor-intensive tasks.
  • Some lenses, such as my Canon EF100mm macro lens, can be set for manual focus and the CamRanger app can still rack focus automatically. It may be necessary to set other lenses for automatic focus in order to work with focus stacking in CamRanger.
  • If possible, use continuous light sources rather than external flash units. I love me some flash triggers, but they’re not 100% reliable. If you’re shooting stills and the flash fails to fire, it’s no big deal — just shoot another shot. Not so when you miss a critical focus layer. I use a combination of two small LED light sources and a Canon Speedlite tethered to the camera by a Vello flash cable; the Canon flash optically triggers a small Nissin i40 external flash (in SD mode) used for backlight.
  • Turn off “sleep mode’ for my Canon 580EX II Speedlite. (C.Fn-01 set for Disabled.)
  • It’s challenging to determine how many layers to shoot for a given focus stack, especially when using smaller step sizes. Don’t sweat it! Simply shoot more layers by starting where the focal plane is at the end of the last focus stack. Repeat as necessary until you capture as many layers as needed.

What’s next?

Going forward, my plan is to experiment with automated focus stacking using subjects that are more complex than the ruler featured in this post. Preliminary testing suggests it could be challenging to create perfect composite images of objects that are more three-dimensional than the ruler.

Sidebar

I used QuickTime to create the embedded movie (shown above) by tethering my iPad mini to a MacBook Air laptop computer and following the excellent directions provided in How To Display your iPad or iPhone on your Mac (9:44), a tutorial video by Terry White, Adobe Evangelist.

Related Resources

Full disclosure: There are hardware/software solutions for wireless tethering and automated focus stacking that are less expensive than CamRanger. Remember, you get what you pay for!

Copyright © 2017 Walter Sanford. All rights reserved.

Time to mate

November 13, 2016

In a recent blog post, I wrote…

Both Blue-faced Meadowhawks and Autumn Meadowhawks are classified as fall species of odonates. In the mid-Atlantic United States, meadowhawks seem to disappear for several months after they emerge during early summer and reappear during fall. Where do they go? No one knows for sure. I speculate Blue-faced Meadowhawks and Autumn Meadowhawks are arboreal species of dragonflies that return to the ground/water when it’s time to mateSource Credit: More previews of coming attractions.

Fall is the time to mate for Autumn Meadowhawk dragonflies (Sympetrum vicinum), as you can see in the following photo.

A mating pair of Autumn Meadowhawk dragonflies (Sympetrum vicinum) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is "in wheel."

06 NOV 2016 | HMP | Autumn Meadowhawk (mating pair, “in wheel“)

This mating pair is “in wheel.” All 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). Dragonflies form the mating wheel in order for their genitalia to connect during copulation.

Odonates (dragonflies and damselflies) are aquatic insects. Most of their life is spent underwater as a nymph. The life span of a nymph depends upon the species: it’s a few months for some species; a few years for other species. Individual adult odonates — like the ones we see flying around Huntley Meadows Park (HMP) — usually live one- to two months, although many different individuals from the same species may be seen for longer periods of time. Adult odonates have one goal: mate in order to reproduce. When fertilized eggs are laid in water, the circle of life comes full circle: eggs; prolarvae; larvae; emergence/adult males and females; mating pairs; males guide females to egg-laying sites (some species, such as Autumn Meadowhawk) or solo females lay eggs (all other species).

Copyright © 2016 Walter Sanford. All rights reserved.


%d bloggers like this: