Archive for the ‘Laowa 25mm Ultra Macro’ Category

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.

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.

MYN – Stygian Shadowdragon exuvia

March 30, 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.

Stygian is the only species of Neurocordulia (Shadowdragons) within range of Wisconsin.

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

Notice the interesting crenulations on the labium (face mask) of the exuvia, including bundles of bristles (setae) along the margins of the palpal lobes.

Tech Tips

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

I set the Laowa 25mm Ultra Macro lens for 2.5x magnification and an aperture of f/5.6, then took some test shots of the subject. Next I shot 23 photos for a focus-stacked composite image showing the face-head-dorsal view of this specimen.

Finally I shot a few photos at f/16, focused manually on the face mask. At the time of this writing, it was too late to create the focus stack so here’s one of the shots at f/16. An aperture of either f/5.6 or f/8 is the “sweet spot” for this lens, according to video reviews I watched. The net result — some image sharpness was sacrificed in favor of more depth of field.

Copyright © 2020 Walter Sanford. All rights reserved.

Laowa 25mm Ultra Macro (Canon mount)

March 23, 2020

Canon EF & RF, Nikon F & Z, Pentax K & Sony FE mounts are available. Source Credit: Laowa 25mm f/2.8 2.5-5X Ultra Macro, Venus Optics.

I bought the Canon mount plus the Canon EF lens to Fujifilm X mount camera adapter for use with my Canon EOS 5D Mark II DSLR and Fujifilm X-Series mirrorless digital cameras.

My Canon 5DM2 features a “full-frame” digital sensor; both my Fujifilm X-T1 and X-T3 cameras feature an APS-C digital sensor.

The following photo is an un-cropped, full size image from the full-frame digital sensor in my Canon 5DM2. Notice how much smaller the subject appears to be in this photo, in contrast with one of the un-cropped, full size images of the same specimen taken with my Fujifilm X-T1.

25mm (2.5x magnification) | ISO 100 | f/8 | 1/200 s | 0 ev

The Fujifilm X-T1 has a crop factor of 1.5x. In addition, the Canon-to-Fujifilm adapter (~1.25″ thick) increases magnification like the net effect of adding one or more extension tubes between the lens and focal plane of the digital image sensor.

The same photo was rotated slightly and cropped for better composition. Pretty good for a one-off shot at an aperture of f/8! Or was it f/5.6? I can’t remember and the EXIF info says f/0 because there aren’t any electronic contacts between the lens and camera body, so no help there.

25mm (2.5x magnification) | ISO 100 | f/8 | 1/200 s | 0 ev

Related Resources

Copyright © 2020 Walter Sanford. All rights reserved.

More Laowa 25mm Ultra Macro

March 20, 2020

The Laowa 25mm Ultra Macro lens is challenging to focus in low light — commentary common to all of the videos I cited in my last blog post (see “Related Resources”) that is consistent with my limited experience using the lens.

As an aid to focusing the camera on the subject, I added a Sunpak LED-160 Video Light to my “Meet Your Neighbours” technique studio photography rig. The bright continuous LED light enabled me to see the red focus peaking displayed by my camera for the first time!

25mm (2.5x magnification) | ISO 200 | f/5.6 | 1/180 s | 0 ev

Both photos featured in this post are “one-offs,” that is, not composite images. Although the depth of field is so shallow that a lot of the subject is out of focus, one look at these photos and I can tell the Laowa lens will work well for creating focus stacks.

25mm (2.5x magnification) | ISO 200 | f/8 | 1/180 s | 0 ev

Both photos are uncropped, full size images from an APS-C digital camera sensor. An aperture of either f/5.6 or f/8 is the “sweet spot” for this lens, according to the video reviews I watched.

The Backstory

The subject is a Common Green Darner dragonfly (Anax junius) exuvia 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.

Copyright © 2020 Walter Sanford. All rights reserved.

Laowa 25mm f/2.8 2.5-5X Ultra Macro

March 18, 2020

The following photograph is among the first set of shots taken using my new Laowa 25mm f/2.8 2.5-5X Ultra Macro lens mounted on my Fujifilm X-T1 APS-C digital camera using the Laowa Lens Mount Adapter (Canon EF – Fuji X).

25mm (2.5x magnification) | ISO 200 | f/5.6 | 1/15 s | 0 ev

The lens is all manual all the time, so it doesn’t really matter that the adapter features no electronic contacts for the lens to communicate with the camera. The lens doesn’t have a focus ring — the user sets the aperture and magnification on the lens and moves the camera/lens rig back-and-forth until focus is achieved.

Among my first impressions, the lens is a “light hog” meaning it requires light and a lot of it for good exposure! Depth of field is extremely shallow, as expected. “One-off” photos like this one are a little disappointing — for best results this lens should be used to create focus stacked composite images.

By now you may be wondering “Why did you buy this Laowa lens?” The two-part answer is simple and straightforward: 1) For the modest price-point of approximately $400 I have a lens that increases the magnification possible using my Fujifilm cameras by a factor of five. 2) I bought the Laowa lens with a Canon mount, so it can be used with either my Canon- or Fujifilm camera bodies. The Laowa Ultra Macro lens/X-T1 kit is significantly smaller and lighter than my Canon MP-E 65mm macro lens/Canon EOS 5D Mark II.

I’m looking forward to further testing of the Laowa lens in the studio as well as in the field.

Related Resources (subject)

Tech Tips

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

The power ratios for an array of four external flash units were as follows: Group A = 1/2 +0.3 (primary backlight); Group B = off (secondary backlight); Group C = 1/32 (subject, stage right); Group D = 1/32 (subject, stage left).

Related Resources (Laowa 25mm Ultra Macro lens)

Copyright © 2020 Walter Sanford. All rights reserved.


%d bloggers like this: