Posts Tagged ‘BoG Photo Studio’

Fossil shark tooth, revisited

June 10, 2022

This blog post features a photo of a fossil shark tooth that I collected from the Lee Creek Phosphate Mine in Aurora, North Carolina. I didn’t record the exact date when I collected this specimen, but it was sometime between 1984 and 1989. The mine is currently open for phosphate mining, but it’s closed to the public for fossil collecting.

At the time I collected the tooth, the species of shark was called Carcharodon megalodon. Subsequently, the scientific name was changed to Carcharocles megalodon.

C. megalodon lived in “shallow” seas approximately 10 million years ago. 10 million years seems like a long time on the human time scale, but isn’t long ago on the Geologic Time Scale.

Size and jaw placement

The following annotated image shows one method for measuring the size of a fossil shark tooth. The “slant height” of the tooth is approximately four and one-quarter inches (~4 1/4″) long, as measured along the straighter edge of the tooth (lower edge, relative to the photo).

According to Gareth Williams, a member of the Megalodon Maniacs Facebook group, the tooth is from the upper jaw (lateral).

Lee Creek Phosphate Mine | C. megalodon (lingual side)

Photoblog post flashback

On 11 May 2020 I published a blog post entitled “Focus bracketing using Fujifilm X-T3” that features the same ruler shown in the preceding photo.

The 7″ plastic ruler is from the Calvert Marine Museum. Do you know why the small ruler is 7″ long rather than the more common 6″ length? Please leave a comment if you know the correct answer. Source Credit: Focus bracketing using Fujifilm X-T3.

The reason the ruler is 7″ inches long is because that’s the length of the largest fossil shark teeth ever collected — the holy grail for fossil hunters!

Tech Tips

The Adobe Photoshop “Ruler Tool” can be used to measure the number of pixels between any two points along the ruler shown in the preceding annotated image.

60s ‘shop: Using the ruler tool to measure distances in Photoshop CC, by Photoshop for the Scientist (1:00) provides a clear and concise explanation of how it’s done.

The resulting value (in pixels) can be used to set a custom scale in Photoshop in order to make other measurements of the tooth virtually.

Related Resources

Copyright © 2022 Walter Sanford. All rights reserved.

Fossil shark tooth

June 3, 2022

Sometimes I start working on a blog post by shooting some quick-and-dirty test shots of the subject, such as the following photos of a fossil shark tooth taken using the “Camera” app on my Apple iPad mini 6. Both photos featured in this post are unedited, that is, they are the original JPGs straight from the “Photos” app on the iPad.

Labial side

The first photo was taken with the built-in camera flash turned on. In my opinion, the light is a little too “harsh.”

The photo shows the side of the tooth that faces outward from the mouth of the shark. Notice the tooth edges are serrated.

There are at least two ways to measure the size of a fossil shark tooth. (More about how to measure shark teeth in a follow-up blog post.) This tooth is approximately four and one-quarter inches (~4 1/4″), as measured along the straighter edge of the tooth (right side, relative to the photo).

Lingual side

The last photo was taken was taken using a small LED light and the flash turned off. The LED lighting is better than the flash light, but the specular reflection located near the upper-middle of the tooth enamel is a little distracting.

The photo shows the side of the tooth that faces inward. Three prominent parts of the tooth are easy to identify in the following photo, including the crown/enamel (top), bourlette (middle), and root (bottom).

In the opinion of the author, the lingual side of a shark tooth is often displayed because it is more visually appealing than the labial side.

What’s next?

I plan to shoot better photos, of course, and annotate some of them in order to make it easier to identify the parts of the tooth.

I will describe when and where I collected the fossil shark tooth, identify the species of shark, and provide an estimate of its approximate age on the Geologic Time Scale.

Finally I will explain how to measure the size of a fossil shark tooth, and how to determine whether the tooth is from the upper- or lower jaw, including its approximate position along the jaw line.

Related Resource: Fossil shark tooth, revisited.

Copyright © 2022 Walter Sanford. All rights reserved.

Test shots

September 17, 2021

I have been working on the prototype for a homemade curved clear plastic tray that is intended for staging subjects against a white background.

My goal for Thursday: Test the prototype stage using a toy mini-lizard as the model for some test shots, and if the proof-of-concept were established, substitute an odonate exuvia for the toy lizard and shoot another set of photos.

16 SEP 2021 | BoG Photo Studio | toy mini-lizard

Well, you know what they say about the best laid plans! First, a line of fairly strong thunderstorms moved through the region where I live so I had to shut down my computer equipment. Second, the Washington Football Team played the New York Giants on Thursday Night Football so I had to watch the game. That’s right, had to watch. Turns out it was time well-spent.

Bottom line: I never finished the test shots of the toy lizard, and of course that means I didn’t shoot any photos of a real scientific specimen.

The curved surface of the clear plastic stage caused reflections from the single external flash that was used to light the subject. I had just figured out a work-around when the thunderstorms rolled in: I took 14 test shots; only the last one (shown above) is usable. I hadn’t intended to create a photo with a pure white background, but it was easy to adjust the image exposure during post-processing.

The Backstory

What’s my motivation? Many macro photographers use insect pins for mounting small subjects like odonate exuviae. I think there’s a big problem with that technique: The position of the pin is permanent. In other words, if the pin is attached to the ventral side of the specimen then it’s challenging at best and impossible at worst to take clean, clear shots of that side of the subject. I don’t want to use insect pins because some of my specimens are one of a kind.

For quite some time, I’ve been experimenting with the use of flat clear plastic stages as a solution for this problem. I think a curved stage might be a breakthrough, but more testing is required to be sure.

For example, notice the color fringing near the tip of the lizard’s tail — I’m not sure what caused that problem in only one part of the photo, therefore I don’t know how to fix it. Yet.

To be continued. Please stay tuned.

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.

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.

 

Dromogomphus spinosus exuvia (dorsal view)

February 19, 2021

Gomphidae (Clubtails) is the second largest family of dragonflies, behind Libellulidae (Skimmers). Many types of clubtail larvae (nymphs)/exuviae look similar, adding to the challenge of identifying some specimens to the genus and species level.

This specimen has a flat labium that doesn’t cover the face (not mask-like), indicating it’s either Aeshnidae (Darners) or Gomphidae; the shape of the body suggets Gomphidae. Several more field marks can be used to identify this specimen as a Black-shouldered Spinyleg (Dromogomphus spinosus) exuvia.

16 FEB 2021 | BoG Photo Studio | D. spinosus exuvia (dorsal)

The specimen is approximately 3.3 cm (~1.3 in) long, measured from head to tail. Notice the mid-dorsal hooks/spines located along the abdomen of the body.

At first I thought the exuvia might be a species from the genus Stylurus, based upon the mid-dorsal spine on abdominal segment nine (S9). After careful examination of two excellent photo-illustrated PowerPoint presentations by Kevin Hemeon at NymphFest 2016 (see Related Resources, below), I noticed none of the species in the genus Stylurus have dorsal hooks. That’s when I realized the specimen must be D. spinosus. Eureka! Source Credit: Dromogomphus spinosus exuvia – a blog post published on 28 June 2019 by Walter Sanford.

Related Resources

The following PowerPoint presentations by Kevin Hemeon are available in the “Files” section of the Northeast Odonata Facebook group. Direct links to the documents are provided below.

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

Tech Tips

The photograph featured in this blog post is a “one-off,” that is, a single photo rather than a focus-stacked composite image. The camera lens was set for f/16; the camera body was set for ISO 160 and a shutter speed of 1/250 s.

The photo was taken using a Fujifilm X-T3 digital camera, Fujifilm MCEX-11 extension tube, Fujinon XF80mm macro lens (120mm, 35mm equivalent), and an array of external lights.

Two external flash units were used to create the white background by cross lighting the front of a piece of white plastic; another flash was used to light the subject. A Sunpack LED 160 was used as a focusing aid.

RAW FILE CONVERTER EX 3.0 was used to convert one RAW (RAF) file to a TIFF file. The TIFF file was edited using Apple Aperture and sharpened using Photoshop.

Copyright © 2021 Walter Sanford. All rights reserved.

MWAA jet airplane pencil eraser

February 12, 2021

The Metropolitan Washington Airports Authority (MWAA) was the school-business partner with Carl Sandburg Middle School (Fairfax County Public Schools) when I worked at the school as a full-time planetarium teacher and later as a part-time planetarium teacher/part-time physical science teacher.

MWAA always brought good SWAG when they participated in school events like the annual “Career Day.” The jet airplane pencil eraser, shown below, was one of the more popular items.

Single image

An MWAA jet airplane pencil eraser was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique. The exposure was increased slightly during post-processing in order to attain a pure white background.

08 FEB 2021 | BoG Photo Studio | MWAA jet airplane pencil eraser

Composite image

The following composite image was created from several photos taken using a Fujifilm X-T3 digital camera, Fujifilm MCEX-11 extension tube, Fujinon XF80mm macro lens, and an array of external lights.

One external flash unit was used to create the white background and another to light the subject. A Sunpack LED 160 was used as a focusing aid.

Seven (7) photos were edited using Apple Aperture, exported as TIFF files, then loaded into Adobe Photoshop CC 2017 in order to create the focus stacked composite image.

08 FEB 2021 | BoG Photo Studio | MWAA jet airplane pencil eraser

Look closely at the pencil shaft and you will notice some serious artifacts from the focus stacking process; more serious artifacts were cropped from the top of the image. Hey, sometimes focus stacking using Photoshop works; sometimes it doesn’t. When it works, it works well; when it doesn’t, well, there are artifacts in the composite image. I have read it’s possible to repair those artifacts, but I’ve never had any luck with that.

Copyright © 2021 Walter Sanford. All rights reserved.

When is a yellow pencil not yellow?

February 9, 2021

A yellow pencil isn’t yellow when the subject is photographed in a studio under artificial light and the photographer is more focused on focus than color fidelity.

08 FEB 2021 | BoG Photo Studio | SANFORD EAGLE yellow pencil

I know what you’re thinking. “Gee, I wish I had a pencil with my last name on it.” But you don’t. Hah! This isn’t one of those cheesy pencils you can order with your name on it — oh no, this “Sanford” brand pencil was manufactured by Newell Brands, a public company headquartered in Atlanta, Georgia. Newell Brands also makes “Sharpie” markers.

Tech Tips

A SANFORD EAGLE yellow pencil was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique. The exposure was increased by 0.2 stop during post-processing in order to attain a pure white background.

The composite image featured in this blog post was created from several photos taken using a Fujifilm X-T3 digital camera, Fujifilm MCEX-11 extension tube, Fujinon XF80mm macro lens, and an array of external lights.

One external flash unit was used to create the white background and another to light the subject. A Sunpack LED 160 was used as a focusing aid.

Six (6) photos were edited using Apple Aperture, exported as TIFF files, then loaded into Adobe Photoshop CC 2017 in order to create the focus stacked composite image.

Announcement: New schedule for publishing blog posts

Beginning on Tuesday, 09 February 2021 blog posts will be published on Tuesday and Friday every week.

I want the followers of my blog to know I struggled with this decision. My decision is based in part on the impact of the pandemic on my day-to-day activities. I’m not sure, but I think this is the first time I’ve mentioned COVID-19 in my blog — I always looked at my blog as a sanctuary from the pandemic for my readers and me. So I soldiered on. That said, with no end in sight for the foreseeable future I must admit I’m started to feel drained and just don’t have the energy to post three times a week.

Going forward, this change might be permanent, at least for the winter months of December, January, and February.

Copyright © 2021 Walter Sanford. All rights reserved.

Alvin? Alvin? Alvin?!?

February 3, 2021

I thought I had figured out how the “FUJIFILM Tether Shooting Plug-in PRO (Mac)” does automated focus bracketing. My working theory was (past tense) the plug-in commands the camera body/lens to move from one auto-focus (AF) focus point to another, based upon the two end-points selected by the user. So I devised a test for my theory. Turns out I was not only wrong, but I’m more confused than ever based upon my test results!

My theory arose from the observation that the focus point changed from the beginning to end of every focus bracket test shoot. For example, the first end-point was near the following focus point…

and the final focus point was near the last end-point.

My camera is set to display 425 AF points. There are 25 AF points in each row, as shown in the first photo.

For the first set of test shots, the plug-in set the number of shots to three (3). That made sense at the time, since I could have selected three AF points manually and covered the image well enough so that the entire subject is acceptably in focus at an aperture of f/16.

During the next two sets of test shots, I selected the same end-points but the plug-in wanted to set the number of shots to greater than 180 photos for both tests. No way I was going to shoot that many photos since my theory was a bust — 180 shots far exceeds 25, the number of AF points in a single row.

Perhaps the number of shots has something to do with the function of the slider for each eye dropper, but I don’t know — I haven’t figured out how the sliders work. (Anyone? A little help, please.)

Alvin

A toy Alvin (the Chipmunks) was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique.

02 FEB 2021 | BoG Photo Studio | toy Alvin (the Chipmunks)

9 photographs were taken using a Fujifilm X-T3 digital camera, Fujifilm MCEX-11 extension tube, and Fujinon XF80mm macro lens, including a set of three photos from my first automated focus bracket test shoot plus some test shots before/after the focus bracket.

The photos were edited using Apple Aperture, exported as TIFF files, then loaded into Adobe Photoshop CC 2017 in order to create the focus stack.

Related Resource: The Chipmunks : The Chipmunk Song (Christmas Don’t Be Late) (2:22)

Copyright © 2021 Walter Sanford. All rights reserved.


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