Archive for the ‘Godox TT685o/p’ Category

As promised…

August 9, 2020

A rare weekend blog post

The following photo was taken by tethering my Fujifilm X-T3 digital camera to an Apple 11″ MacBook Air computer, via a TetherTools USB cable. Fujifilm X Aquire (free) was used to save JPG files to a folder on the desktop of my MacBook Air; both JPG and RAF files were saved to one of two memory cards in the X-T3.

Apple “Preview” was used to view the JPG files saved to my MacBook Air. Looking at larger versions of the photos than can be seen on the X-T3 LCD enabled me to position the exuvia exactly as I wanted.

Notice the left eye is overexposed slightly (as well as the farthest tip of the left middle leg), probably caused by positioning the subject too close to the white background. Hey, it’s been a while since I did much studio macro photography — I need to play myself into game shape!

More details, including some of the tips and tricks I promised, will be provided in my regularly-scheduled blog post on Monday, 10 August 2020. Please stay tuned!

The Backstory

Swift River Cruiser dragonfly (Macromia illinoiensisexuvia was collected on 27 May 2017 along the Potomac River at Riverbend Park in Fairfax County, Virginia USA. This individual is a female.

Copyright © 2020 Walter Sanford. All rights reserved.

Flash photography: Backlighting the background

August 3, 2020

The following annotated photo shows a recent iteration of my “Meet Your Neighbours” (MYN) technique studio macro photography rig, set up at BoG Photo Studio, Fairfax County, Virginia USA.

The rig has evolved since the photo was taken: On the flash used to backlight the background, I exchanged the Lastolite Ezybox Speed-lite 2 (No. 7, above) for a small altura PHOTO softbox that seems to work as well as the larger Lastolite softbox. The swap enables me to use the two larger softboxes for lighting the subject.

In my last blog post, I posed a question.

How far should should an external flash unit fitted with some type of diffuser be positioned from the backside of a translucent white plastic sheet used to create a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique? Source Credit: Flash photography: 1:1 rule-of-thumb, by Walter Sanford.

Disclaimer: The following information explains how I figured out the answer to my question. Trial and error experimentation suggests my answer is valid. Opinions to the contrary are invited and welcome.

altura PHOTO flash diffuser

Imagine an isosceles triangle with an external flash unit at Point A, shown below, pointed toward Line BC. Line BC represents the translucent white plastic sheet (No. 2, above) that I use for the background when shooting small objects such as the odonate exuvia posed on a clear plastic stage (No. 3, above). Note: The white plastic sheet is actually 12″ square. I used a value of 12.1″ because the calculator doesn’t allow me to choose 12.0″. Go figure!

In the last post, we learned that the face of the Altura softbox should be positioned at a distance of 7.8″ or less from the subject; this is the altitude of the triangle shown below. Notice that Angle A is 76 degrees. Experiment with the Isosceles Triangle calculator by moving Point A (the external flash) closer to Line BC (the backside of the background); notice that Angle A increases as the altitude of the triangle decreases.

Isosceles Triangle calculator output courtesy Math Open Reference.

Have you noticed that your external flash unit has a “Zoom” setting? It does, or it should. It would be so simple if the increments for Zoom were in angular degrees. Instead, the units are in millimeters of focal length, as in the focal length of a lens. This where the water gets muddy!

The “field of view” for a given lens is determined by the 35mm equivalent of the lens and the size of the camera sensor. The same lens has a different field of view depending upon whether it is mounted on either a full-frame or crop-sensor camera. Long story short, check the table entitled “Focal lengths with same field of view” that’s embedded in the article “Focal Length and Field of View Explained in 4 Steps” in order to determine the Zoom setting for your external flash.

As a practical matter, choose the Zoom setting for a field of view that is closest to Angle A. The Zoom setting (field of view) can be wider than Angle A but shouldn’t less than Angle A because that will cause a “hotspot” on the background.

Lastolite flash diffuser

For what it’s worth, here’s the Isosceles Triangle calculator output for the Lastolite flash diffuser shown in the photo at the beginning of this blog post. Notice the face of the flash diffuser is positioned closer than 12.2″ from the background, so Angle A will be larger than 52 degrees. Set the Zoom function accordingly.

Isosceles Triangle calculator output courtesy Math Open Reference.

Related Resources

Copyright © 2020 Walter Sanford. All rights reserved.

Common Green Darner dragonfly (external female reproductive anatomy)

June 5, 2020

For some species of odonate exuviae, sex is indicated by a form of remnant reproductive anatomy. These external structures don’t look exactly the same for all species of dragonflies and damselflies, but their function is identical.

As far as I know, this is true for all species in the Family Aeshnidae (Darners) such as Common Green Darner dragonfly (Anax junius).

The following photograph shows a ventral view of a female Common Green Darner dragonfly. Notice the external reproductive anatomical structure on abdominal segment nine (S9) is virtually identical to the remnant anatomical structure on S9 of the exuvia, shown above.

Original photo used with permission from Louisa C. Craven.

The Backstory

My dear friend Louisa Craven discovered the lifeless adult dragonfly while on vacation with her family in Nags Head, North Carolina USA. Louisa is an accomplished wildlife photographer who developed an interest in odonates as a result of many photowalks with me.

Related Resources

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Hylogomphus adelphus exuvia (dorsal)

May 4, 2020

The following Anisoptera exuvia — collected by Freda van den Broek on 10 June 2019 along the St. Croix River in Polk County, Wisconsin USA — is definitely a member of Family Gomphidae (Clubtails), probably Mustached Clubtail (Hylogomphus adelphus).

Dorsal view

The abdomen is wider than the head. Vestigial mid-dorsal hooks are noticeable along several abdominal segments, especially segment nine (S9). A “median groove” is apparent along part of the abdomen. The lateral spine on S9 is spinulose-serrate along the outer edge.

10 JUN 2019 | Polk County, WI | H. adelphus exuvia (dorsal)

Related Resources

Tech Tips

This subject was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique.

15 photos of the specimen were taken using an aperture of f/16; in-camera focus peaking was used to highlight select areas in each photo. Adobe Photoshop CC 2017 was used to create- and annotate the focus-stacked composite image shown above.

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Hylogomphus adelphus exuvia (ventral)

May 1, 2020

The following Anisoptera exuvia — collected by Freda van den Broek on 10 June 2019 along the St. Croix River in Polk County, Wisconsin USA — is definitely a member of Family Gomphidae (Clubtails), probably Mustached Clubtail (Hylogomphus adelphus).

Ventral view

Notice the exuvia has a flat labium (prementum). There are lateral spines located on abdominal segments six through nine (S6-S9); the lateral spine on S9 is spinulose-serrate along the outer edge. Also notice the well-developed tibial burrowing hooks on its legs.

10 JUN 2019 | Polk County, WI | H. adelphus exuvia (ventral)

Male (vestigial genitalia)

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).

Both sets of vestigial genitalia are clearly visible on the ventral side of some (but not all) specimens, such as the H. adelphus exuvia shown above.

Related Resources

Tech Tips

This subject was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique.

12 photos of the specimen were taken using an aperture of f/16; in-camera focus peaking was used to highlight select areas in each photo. A subset of six (6) photos and Adobe Photoshop CC 2017 were used to create- and annotate the focus-stacked composite image shown above.

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Too dark or too light?

April 27, 2020

The following Anisoptera exuvia — collected by Freda van den Broek on 10 June 2019 along the Red Cedar River in Barron County, Wisconsin USA — is definitely a member of Family Gomphidae (Clubtails), possibly Rusty Snaketail (Ophiogomphus rupinsulensis).

Dorsal-lateral view

Nine (9) photos of the specimen were taken using an aperture of f/16; in-camera focus peaking was used to highlight select areas in each photo. Adobe Photoshop CC 2017 was used to create the focus-stacked composite image shown below.

10 JUN 2019 | Barron County, WI | Anisoptera exuvia (dorsallateral)

When I previewed the RAW files used to create the preceding composite image, I thought most of the files look too dark.

So I did a do-over using 15 photos, resulting in a new version of the composite that is perfectly in focus but a little too light. Compare/contrast the two composite images and you should notice it’s easier to see the mid-dorsal hooks along the abdomen in the first image. The primary purpose for the images is to illustrate those field marks, therefore I think the first (darker) image is better.

10 JUN 2019 | Barron County, WI | Anisoptera exuvia (dorsallateral)

Face-head-dorsal view

Five (5) photos of the specimen were taken using an aperture of f/16; in-camera focus peaking was used to highlight select areas in each photo. Adobe Photoshop CC 2017 was used to create the focus-stacked composite image shown below.

10 JUN 2019 | Barron County, WI | Anisoptera exuvia (face-head-dorsal)

My first impression of the version shown above is it’s too dark, and I second-guessed myself for not shooting more photos for the focus stack.

I created a new focus-stacked composite image using a little more light and 14 photos. When I examined the RAW files used to create the new composite image (shown below), I thought most of the files still look too dark. (But I was wrong.)

10 JUN 2019 | Barron County, WI | Anisoptera exuvia (face-head-dorsal)

So I created a third version using much more light and 24 photos. Although it’s debatable which image looks best, the first- and second images show a few key field marks of the antennae better than the third image.

It turns out the antennae are one indicator this specimen is from the genus Ophiogomphus (Snaketails), so the first two (darker) images are the winners once again.

10 JUN 2019 | Barron County, WI | Anisoptera exuvia (face-head-dorsal)

For what it’s worth, the second of three images is my favorite as indicated by the fact that the image is cropped so there’s room for annotations.

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Clubtail exuvia (dorsal-lateral view)

April 24, 2020

The following Anisoptera exuvia — collected by Freda van den Broek on 10 June 2019 along the Red Cedar River in Barron County, Wisconsin USA — is definitely a member of Family Gomphidae (Clubtails), possibly Rusty Snaketail (Ophiogomphus rupinsulensis).

10 JUN 2019 | Barron County, WI | Anisoptera exuvia (dorsallateral)

Notice the exuvia has little stubby mid-dorsal hooks along the length of its abdomen, and lateral spines on abdominal segments seven through nine (S7-S9).

Tech Tips

This subject was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique.

15 photos of the specimen were taken using an aperture of f/16; in-camera focus peaking was used to highlight select areas in each photo. Adobe Photoshop CC 2017 was used to create the focus-stacked composite image shown above.

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Clubtail exuvia (species unknown)

April 15, 2020

An Anisoptera exuvia was collected by Freda van den Broek on 10 June 2019 along the Red Cedar River in Barron County, Wisconsin USA.

This specimen is definitely a member of Family Gomphidae (Clubtails), possibly Midland Clubtail (Gomphurus fraternus).

10 JUN 2019 | Barron County, WI | Anisoptera exuvia (dorsallateral)

Tech Tips

This subject was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique.

During this photo shoot, I tested the Flash Diffuser Light Softbox by Altura Photo (6″ x 5″) for the first time. This relatively inexpensive softbox ($12.99) is highly recommended by Allan Walls, an excellent photographer who specializes in macro photography. I must admit I was more than a little skeptical but the diffuser seems to work as advertised and is a remarkable bargain, unlike my expensive Lastolite softbox flash modifiers (8.5” x 8.5” square).

The 1:1 rule-of-thumb is used to determine how close/far to position a flash unit from the subject. The diagonal distance across the face of a softbox should be the distance to the subject [or less] for soft wrap-around light. Actually, the distance should be as close as possible without the softbox showing in the photo frame. Greater distances will result in a contrasty look.

For example, my new Altura softbox is a 6” x 5” rectangle (7.8” diagonally) so it should be positioned ~8″ or less from the subject. Buyer beware: This distance is OK for macro photography but not OK for most other types of photography.

Related Resources

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Anisoptera exuvia (species unknown)

March 13, 2020

An Anisoptera exuvia (species unknown) was collected by Mike Powell, my good friend and photowalking buddy. Although the exact date and location are unknown, we know the specimen was collected sometime during 2019 somewhere in Northern Virginia.

The specimen is definitely a dragonfly, probably from either Family Corduliidae (Emeralds) or Family Libellulidae (Skimmers), as indicated by its mask-like labium and thin antennae.

2019 | Anisoptera exuvia (face-head-dorsal)

Related Resource: MYN – Anisoptera exuvia (dorsal view). [Dorsal view of the same specimen featured in this blog post.]

Tech Tips

This subject was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique.

Three photos were used to create a composite image: two photos focused on the head; and another photo focused on the prementum. I must say I’m fairly pleased by the way the final image turned out, best appreciated by viewing the full-size version of the composite.

My Canon EOS 5D Mark II is a full-frame DSLR digital camera. RAW images are 5616 × 3744 pixels. The dimensions of the composite image are 5385 × 3657 pixels, that is, slightly smaller than full-frame. It’s usually necessary to crop composite images, at least a little, because the individual photos used to create the composite don’t align perfectly, even when the camera is mounted on a tripod (as it was in this case).

For what it’s worth, the following camera settings were used to shoot all three photos: 100mm; ISO 100; f/8; 1/200 s; 0 ev. The power ratios for an array of four external flash units were as follows: Group A = 1/16 (primary backlight); Group B = 1/32 (secondary backlight); Group C = 1/4 (subject, stage right); Group D = 1/8 (subject, handheld stage left).

I’m still searching for the “sweet spot” for this camera/lens combo. The white background was slightly under-exposed by approximately 1.5 stops, so I need to increase the flash power ratios for Group A and B. The subject was exposed almost perfectly, so Group C and D are close to spot on. Trial and error is the MYN way!

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Anisoptera exuvia (species unknown)

March 11, 2020

An Anisoptera exuvia (species unknown) was collected near a small pond at Occoquan Regional Park (ORP), Fairfax County, Virginia USA.

This individual probably is a member of the Family Libellulidae (Skimmers), as indicated by its anal pyramid. The small pond where the specimen was collected is perfect habitat for skimmers.

01 JUN 2019 | ORP | Anisoptera exuvia (dorsallateral view)

Related Resource: Another unknown species of odonate exuvia – a blog post by Walter Sanford featuring a “one-off” photo (that is, not a composite image) of the same specimen.

Tech Tips

This subject was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique.

Two photos were used to create a composite image: one photo focused on the head; and another photo focused on abdominal segments seven (S7) through nine (S9).

My Canon EOS 5D Mark II is a full-frame DSLR digital camera. RAW images are 5616 × 3744 pixels. The dimensions of the composite image are 5589 × 3743 pixels, that is, essentially full-frame. It’s usually necessary to crop composite images, at least a little, because the individual photos used to create the composite don’t align perfectly, even when the camera is mounted on a tripod (as it was in this case).

For what it’s worth, the following camera settings were used to shoot both photos: 100mm; ISO 100; f/8; 1/200 s; 0 ev. I need to tweak the settings a little in order to find the “sweet spot” for this camera/lens combo: the white background was slightly over-exposed; and the subject was slightly under-exposed. Of course that means I need to tweak the flash power for the backlights and add one or more additional external flash units for more fill flash. Overall, I’m fairly satisfied with the results of my first attempt using the MYN technique with this camera rig.

Copyright © 2020 Walter Sanford. All rights reserved.


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