Archive for the ‘Laowa 25mm Ultra Macro’ Category

Swift River Cruiser exuvia (face-head)

November 20, 2020

The following image is a focus-stacked composite of three photos, focused on the left eye, right eye, and both eyes respectively.

27 May 2017 | Riverbend Park | Swift River Cruiser (exuvia, face-head)

Tech Tips

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

Several photos were taken using my Canon EOS 5D Mark II digital camera, a Kenko 12mm extension tube, and Laowa 25mm Ultra Macro Lens, set for f/4.0 (the sweet spot for this lens) at ~3.0x magnification.

Godox TT685C external flash was used to backlight the background (a piece of translucent white plastic) and a Godox TT685F external flash was used as a key light on the right side of the subject. The flash was triggered wirelessly by a Godox X2TC.

Check the EXIF/IPTC info for the photograph for complete details regarding photo gear and camera settings.

Adobe Photoshop CC 2017 was used to create a focus-stacked composite image that was edited using Apple Aperture.

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.

When is close too close?

October 14, 2020

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. The prominent horn on the head — a key field mark for exuviae from Family Macromiidae (Cruisers) — is noticeable in the following photo, although maybe not recognizable.

This photo is one of several test shots using “The Macroscope,” my nickname for the Laowa 25mm Ultra Macro Lens. The Laowa lens was mounted on my Canon 5D Mark II digital camera with a 12mm Kenko extension tube between the lens and camera body.

My new Laowa LED Ring Light was mounted on the front of the lens, powered by an Anker PowerCore+ 26800 PD 45W battery. The Laowa LED Ring Light was used to light the subject. A Sunpak LED-160 Video Light was used as a focusing aid. A Godox TT685C external flash was used to backlight a translucent white plastic background, using the “Meet Your Neighbours” technique. The flash was triggered wirelessly by a Godox X2TC.

The image is full-frame (5616 by 3744 pixels), that is, uncropped. The lens was set for f/4 (the “sweet spot” for the lens) at 4x magification. The camera was set for single point focus and spot metering, centered on the right eye of the exuvia.

Look closely at a full-size version of the image. At this magnification, the depth of field is very shallow: remnant ommatidia are clearly in focus; most of the image is out of focus.

In order to provide some context for what is shown in the first photo, the last photo shows the entire specimen. The photo gear used to take the shot is specified in a previous blog post.

When is close too close?

Close is too close when most of the subject is unrecognizable. At 4x magnification, it’s essential to use focus stacking to create a composite image.

The bigger take-away from this test shot is the Laowa LED Ring Light seems to work fairly well, albeit a sample size of one.

Related Resources

Copyright © 2020 Walter Sanford. All rights reserved.

Anker PowerCore+ 26800 PD 45W

October 12, 2020

In my experience, digital camera batteries are the weak link during extended macro photo shoots — it seems like they never last long enough and always go dead at the worst possible time! So I started searching for portable power solutions that would solve the problem.

I stumbled across an FAQ page on the Fujifilm Global Web site that provides information regarding two mobile batteries recommended by Fujifilm. Warning: Be patient — the FAQ page takes a LONG TIME to load!

Both batteries are made by Anker; the more powerful model is no longer available. As far as I can tell, the PowerCore+ 26800 PD 30W version of the battery featured on the FAQ page was replaced by a new model (Anker PowerCore+ 26800 PD 45W). Editor’s Note: One or more upcoming blog posts will be related to using the Anker battery as a power source for select Canon- and Fujifilm digital cameras.

The same battery can be used to power the Laowa LED Ring Light that is featured in my last blog post. When I was doing my homework before deciding to buy the ring light, the first thing I noticed is it doesn’t feature an On/Off switch. I thought, “No problem, the Anker battery has one.” See that big button on top of the battery, shown below? Naturally I assumed it’s an On/Off switch. Wrong! The fact is, I have NO IDEA what that button does other than indicate whether the battery is fully-charged. This battery is essentially a fire hose of power that’s always on when a device is plugged into one of its USB ports. Needless to say, that’s less than ideal for use with the LED ring light.

Product image courtesy AnkerDirect.

Similar to GoPro’s dizzying array of nearly identical action cameras, Anker sells so many types of batteries (including variants of the same model) that it can cause decision paralysis! For what it’s worth, I bought the PowerCore+ 26800 PD 45W that includes an AC charger.

Product image courtesy AnkerDirect.

If you have purchased a product from Apple, then you know the unboxing experience is one of life’s simple pleasures — the attention to detail is astounding! And so it is/was with the packaging for the Anker battery I bought. Regrettably the joy ends abruptly when you attempt to read the documentation provided with the product — it’s practically unintelligible! Seriously, I have learned more about the battery by watching independently-produced YouTube videos than by reading the User Manual.

Product image courtesy AnkerDirect.

On/Off Switch

After an exhaustive Google search, I discovered a (relatively) short USB extension cable that features an on/off switch. The product is sold in a two-pack of cables.

Product image courtesy RIITOP Store (on Amazon).

In my opinion, it’s important to choose a USB extension cable that can be used for both data and power in order to maximize the usefulness of the cable.

Product image courtesy RIITOP Store (on Amazon).

A USB power cable is provided with the Laowa LED Ring Light. I connect the Laowa cable to the LED ring light, then connect the other end to one of the RIITOP cables with an On/Off switch. Finally, plug the RIITOP cable into the Anker battery.

What are the take-aways?

In my strong opinion, the Laowa LED Ring Light would be greatly improved by adding two inexpensive features: an On/Off switch; and a dimmer switch. C’mon Laowa — my suggestions are a no-brainer!

And if Venus Optics (Laowa) were feeling ambitious, they should engineer a solution that would enable the LED ring light to be powered directly from the hot shoe of a digital camera. Hot shoe pin-outs vary by brand of camera, but the middle pin is always used for power so one connector should work with all types of cameras. Do it!

And while I’m talking about no-brainers, c’mon Anker — is there a compelling reason your mobile batteries don’t feature an On/Off switch?

Related Resources

This blog post is one in a series of posts related to continuous AC power and long-lasting battery power for select Canon, Fujifilm, and Panasonic digital cameras.

Copyright © 2020 Walter Sanford. All rights reserved.

Laowa LED Ring Light for 25mm Ultra Macro Lens

October 9, 2020

I prefer artificial light from electronic flash units rather than continuous light sources such as LEDs. That being said, when the working distance between lens and subject is small, a lens-mounted LED ring light makes sense to use.

Minimum focusing distance versus working distance

The “minimum focusing distance” is the distance from the subject to the focal plane. The “working distance” is the distance from the front of the lens to the subject. For macro photography, usually the latter is more important than the former.

According to Venus Optics (Laowa), the minimum focusing distance for the “Laowa 25mm f/2.8 2.5-5x Ultra Macro lens” is 23.4 cm at 2.5x magnification and 17.3 cm at 5x. According to several Web sites, the working distance is 45 mm (4.5 cm) at 2.5x and 40 mm (4.0 cm) at 5x, or a range of working distances from ~1.8 to ~1.6 inches.

Adding one or more extension tubes reduces the working distance and increases magnification. For example, adding a Kenko 12mm extension tube reduced the working distance from 45 mm to ~30 mm at 2.5x.

And it’s worth noting that adding the Laowa “Canon EF lens to Fujifilm X mount camera adapter” to the lens further reduces the working distance — the adapter is ~26 mm wide, essentially equivalent to adding a 26mm extension tube. Combined with the 1.5x crop factor of Fujifilm X-Series cameras such as the X-T1 and X-T3, it’s no wonder the magnification of the lens is increased dramatically when used with select Fujifilm cameras!

Ultra Macro Lens

The first two photos, courtesy B&H Photo, show the version of the Laowa lens for Canon EF. For what it’s worth, f/4 is the “sweet spot” for this lens.

Product image courtesy B&H Photo.

Look closely at the front of the lens. Notice a “flange” (one of two) that is visible around the outer rim of the lens. Those flanges are used to mount the Laowa LED ring light on the lens.

Product image courtesy B&H Photo.

LED Ring Light

The next two photos, courtesy Allen’s Camera, show the Laowa LED ring light.

Product image courtesy Allen’s Camera.

The LED ring light ships with a USB power cable. A power source for the ring light is NOT INCLUDED. My next blog post will feature a discussion of the pros/cons of the power source solution I decided to use.

Product image courtesy Allen’s Camera.

LED mounted on lens

The last photo shows the Laowa LED Ring Light mounted on the Laowa Ultra Macro Lens that is mounted on my Canon 5D Mark II digital camera. The USB power cable is connected to the LED ring light but not connected to a power source. (Don’t mind the clutter in the background!)

Notice the face of the LED ring light extends ~5 mm beyond the front of the lens, thereby reducing the working distance by ~5 mm (~0.5 cm). Plan accordingly.

Laowa LED and 25mm Ultra Macro lens mounted on Canon 5D Mark II.

Related Resources

Copyright © 2020 Walter Sanford. All rights reserved.

Macromia illinoiensis exuvia (face-head) redux

May 22, 2020

A Swift River Cruiser dragonfly (Macromia illinoiensis) exuvia was collected, with permission from park staff, on 27 May 2017 along the Potomac River at Riverbend Park in Fairfax County, Virginia USA.

The preceding image shows the remnant ommatidia clearly.

From this viewpoint, it’s harder to see the prominent horn on the face that is a key field mark for larvae/exuviae in the Family Macromiidae (Cruisers). The base of the triangular horn is located above the labium (face mask), between the long, thin antennae; the apex of the triangle is pointed toward the viewer.

It’s easier to see the horn in the featured photo in my last blog post.

Tech Tips

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

20 photos of the specimen were taken using 2.5x magnification at an aperture of f/4; in-camera focus peaking was used to highlight select areas in each photo. RAW FILE CONVERTER EX 3.0 was used to convert Fujifilm RAF files to TIFF files. Adobe Photoshop CC 2017 was used to create a focus-stacked composite image that was edited using Apple Aperture.

Copyright © 2020 Walter Sanford. All rights reserved.

Adequate packing material for safe shipping?

May 13, 2020

I ordered a Laowa 25mm Ultra Macro lens from B&H Photo on 10 March 2020. The parcel was delivered a few days later on 14 March.

The first photo shows contents of the larger cardboard box in which the lens was shipped.

The last photo shows the larger cardboard box after I removed the smaller box containing the lens.

Notice there was NO PACKING MATERIAL on four of six sides of the smaller box for the lens. That can’t be good for shipping a camera lens safely!

During limited testing of the new lens, I haven’t been completely satisfied with its performance. I can’t help but think, was the lens damaged slightly during shipping? I’ll never know but I’ll always wonder.

What are the take-aways?

I remember opening the box of my first order from B&H Photo many years ago. My first impression was something like, “Wow! The items in my order were packed carefully to ensure they arrived in great condition.” Those days are long gone.

The fact of the matter is the problem of inadequate packing material seems to be the new normal at B&H Photo, and that doesn’t work for me — photo gear is too expensive to cut corners on shipping! C’mon B&H, you can and should do better.

Copyright © 2020 Walter Sanford. All rights reserved.

Cobra Clubtail versus Midland Clubtail

April 20, 2020

Odonate exuviae from two species in Genus GomphurusCobra Clubtail (Gomphurus vastus) and Midland Clubtail (Gomphurus fraternus) — are nearly perfect body doubles, with the exception of one key field mark that can be used to differentiate the species.

Dorsal views

Lateral spines are located on abdominal segments six through nine (S6-S9) for both species.

10 JUN 2019 | Barron County, WI | Midland Clubtail exuvia (dorsal)

Ventral views

The overall shape of the prementum is similar for both species.

10 JUN 2019 | Barron County, WI | Midland Clubtail exuvia (ventral)

Prementum (ventral view)

The shape of the palpal lobes on the prementum is different for the two species, as shown in the following diagram on p. 15, Key to the species of genus GomphurusIdentification Keys to Northeastern Anisoptera Larvae, compiled by Ken Soltesz.

The following images are magnified approximately three and one-half times life size (~3.5x).

For both species, focus on the row of teeth along the right palpal lobe. Notice the strongly curved shape of the palpal lobe for Cobra Clubtail (shown above), in contrast with the gently arched shape of the palpal lobe for Midland Clubtail (shown below). Also notice the Cobra palpal lobe has fewer teeth than Midland.

10 JUN 2019 | Barron County, WI | Gomphurus fraternus (exuvia)

Adults

Adult Cobra Clubtail dragonflies are almost identical to Midland Clubtails too. Several field marks can be used to differentiate the two species. In my opinion, one field mark is the easiest to recognize where it really matters — in the field!

16 MAY 2016 | Riverbend Park | Cobra Clubtail (adult male)

Notice there aren’t any mid-dorsal marks on abdominal segments eight and nine (S8-S9) for Cobra Clubtail (shown above). In contrast, there is a small yellow triangle on abdominal segment eight (S8) for Midland Clubtail (shown below). This is true for males and females of both species.

Photo used with permission from Freda van den Broek.

Copyright © 2020 Walter Sanford. All rights reserved.

Neurocordulia yamaskanensis exuvia

April 13, 2020

A Stygian Shadowdragon dragonfly (Neurocordulia yamaskanensis) exuvia was collected by Freda van den Broek on 10 June 2019 along the St. Croix River in Interstate Park, Polk County, Wisconsin USA.

A two-step process was used to verify the genus and species of the exuvia.

  1. Determine the family.
  2. Determine the genus and species.

Step 1. Family

First, determine the family of the specimen. For reference, watch the excellent Vimeo video, Identifying dragonfly larva to family (8:06). Here’s the decision tree used to identify the exuvia as a member of the Family Corduliidae (Emeralds).

  • The specimen has a mask-like labium (prementum) that covers the face, as shown in Image No. 1, characteristic of four families of odonates: Cordulegastridae (Spiketails); Corduliidae (Emeralds); Libellulidae (Skimmers); and Macromiidae (Cruisers).
  • There is no horn on the face-head, characteristic of Macromiidae, so it’s not a cruiser.
  • Cordulegastridae has angular, jagged crenulations on its labium, so it’s not a spiketail. The crenulations for Corduliidae and Libellulidae can look similar.
  • Look at the anal pyramid to differentiate Corduliidae and Libellulidae: It’s probably Corduliidae if the cerci are at least half as long as the paraprocts. [Editor’s Note: It’s probably Libellulidae if the cerci are less than half the length of the paraprocts.]

In summary, the exuvia has a mask-like labium, and no horn on its face-head. The deeply-scalloped crenulations along the margins of the palpal lobes are a characteristic field mark for Genus Neurocordulia (Shadowdragons) in the Family Corduliidae (Emeralds), according to Kevin Hemeon, member of the “Odonate Larvae and Exuviae” Facebook group.

Although the anal pyramid isn’t shown clearly in any of the photos in this field guide, careful examination of photos of the teneral adult that emerged from the exuvia (see The Backstory, below) confirmed the dragonfly is a Stygian Shadowdragon. Stygian is the only species of Neurocordulia (Shadowdragons) within range of Wisconsin.

A face-head view of the exuvia is shown in Image No. 1, magnified approximately two and one-half times life size (~2.5x). Notice the mask-like labium that covers the face of the exuvia, including deeply-scalloped crenulations with bundles of bristles (setae) located along the margins of the palpal lobes.

No. 1 | Neurocordulia yamaskanensis | exuvia (face-head)

Step 2. Genus and species

Dichotomous keys from Identification Keys to Northeastern Anisoptera Larvae, compiled by Ken Soltesz, were used to verify the genus and species of the exuvia. Field marks that match this specimen are highlighted in boldface green text.

Key to the Genera of the Family Corduliidae, p. 28.

1a. Pair of small tubercles on top of head; Lateral lobe of labium with 4 or 5 setae (except sometimes 6 or 7 in Neurocordulia). (2)

2a. Strong lateral spines of abdominal segment 8 very divergent and as strong as parallel spines of [S]9. (Neurocordulia)

Alternate Key to the Genera of the Family Corduliidae, p. 29.

1a. Dorsal hooks present and well developed on some of the abdominal segments. (2)

2a. Lateral spines present on segment 8. (3)

3a. Crenulations on distal margin of labial palpi nearly semicircular or even more deeply cut; Lateral spines on segment 8 divergent. (Neurocordulia)

Key to the Species of the Genus Neurocordulia, p. 31.

1b. Lateral spines of 9 about 30 to 50 percent of the length of segment 9, not extending beyond the tips of the caudal appendages; Dorsal hooks of segments 7 to 9 reduced to scarcely more than a short ridge; Length 22 – 24.5 mm. (yamaskanensis)

The following annotated focus-stacked composite images illustrate key field marks described in Soltesz’s dichotomous keys.

Notice the specimen has stubby mid-dorsal hooks along the length of its abdomen, as shown in Image No. 2.

Lateral spines are present on abdominal segments eight and nine (S8-S9): the lateral spines on S8 are divergent; the ones on S9 are parallel.

The exuvia is ~2.4 cm (~0.95 in) in length — the longest shadowdragon larva/exuvia in the genus Neurocordulia. Notice the lateral spines on abdominal segment nine (S9) don’t extend beyond the tips of the caudal appendages (terminal appendages), as shown below.

The Backstory

The following narrative was provided by Freda van den Broeck.

On the last morning of the Wisconsin Dragonfly Society Annual Meeting weekend — Sunday, June 10th 2019 — I made my way to the boat landing in Interstate Park, St. Croix Falls, Wisconsin USA.

The previous morning I’d photographed Mustached Clubtail emerging there (with Alon Coppens). We also saw several teneral Rapids Clubtails. One didn’t have to look hard to find exuviae — they were most easily seen on the rocks, just a couple of feet above the water line. I was really hoping to find a Snaketail emerging, but had no such luck.

Photo of St. Croix river used with permission from Freda van den Broek.

Just as I was about to head back to the car, I spotted a teneral, that had crawled up the rock face higher than I would have expected. At that point, I thought it was “just another baskettail” — we’d seen many of them on Friday afternoon and Saturday. But it was pretty and shiny, so I had to take a few pictures, even though I was late for breakfast. (It was around 8:20 am.)

It was several days later before I realized that it wasn’t a baskettail, but a Shadowdragon, and that a few of the exuviae I’d collected there were Stygian Shadowdragons. Source Credit: Freda van den Broek.

Photo used with permission from Freda van den Broek.

Tenerals are usually tough to identify, but you’ll notice in both photos that the [small yellow] spot on [side of] the thorax is clearly visible. Source Credit: Freda van den Broek.

Photo used with permission from Freda van den Broek.

Related Resources

Odonate Exuviae – a hyperlinked list of identification guides to many species of odonate exuviae from seven families of dragonflies and three families of damselflies.

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – N. yamaskanensis exuvia (face-head)

April 10, 2020

The following annotated focus-stacked composite image shows a Stygian Shadowdragon dragonfly (Neurocordulia yamaskanensis) exuvia collected by Freda van den Broek on 10 June 2019 along the St. Croix River in Interstate Park, Polk County, Wisconsin USA.

10 JUN 2019 | Polk County, WI | Stygian Shadowdragon (exuvia)

Notice the unusual shape of the crenulations between the palpal lobes of its mask-like labium. Is this field mark unique to N. yamaskanensis or common to all species of the genus Neurocordulia (Shadowdragons)? Enquiring minds want to know!

Tech Tips

Laowa 25mm Ultra Macro lens, set for 2.5x magnification, and Canon EOS 5D Mark II DSPLR was used to photograph the subject against a pure white background (255, 255, 255) following the “Meet Your Neighbours” (MYN) technique.

24 photos were used to create the composite image, including 23 photos taken using an aperture of f/5.6 and one photo taken at f/16.

If you look closely at the full-size version of the image, then you will notice some areas that indicate the final image is a few layers short of a perfect focus stack. But hey, not bad for a new lens and a manual focus rail that I used for the first time!

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Focus-stacked composite image

April 3, 2020

The following focus-stacked composite image shows a Stygian Shadowdragon dragonfly (Neurocordulia yamaskanensisexuvia collected by Freda van den Broek on 10 June 2019 along the St. Croix River in Interstate Park, Polk County, Wisconsin USA.

10 JUN 2019 | Polk County, WI | Stygian Shadowdragon (exuvia)

Related Resources

Tech Tips

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

24 photos were used to create the composite image, including 23 photos taken using an aperture of f/5.6 and one photo taken at f/16.

If you look closely at the full-size version of the image, then you will notice some areas that indicate the final image is a few layers short of a perfect focus stack. But hey, not bad for a new lens and a manual focus rail that I used for the first time!

Copyright © 2020 Walter Sanford. All rights reserved.


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