Sunday, March 30, 2008

The Dragonflies and Damselflies of the Olentangy River

Megan and I live near the Olentangy River, exactly 890 feet from the river, as measured using Google Maps. Over the past summer, I was photographing damselflies and dragonflies almost every day. What I have presented here is a timeline of the dragons along the river. Each image represents the first encounter I had with each species. The common name, scientific name, and date of first observation is given below each image. A link is provided to a range map at the Ohio Odonata Society Website. Also, I have uploaded the images in full resolution- clicking each image will link to a higher resolution version. I'm most interested in getting people's feedback on the rapids clubtail and the arrow clubtail.

Female ebony jewelwing, Calopteryx maculata.
May 28, 2007.

Stream bluet, Enallagma exsulans. June 3, 2007.

Powdered dancer, Argia moesta. June 3, 2007.

Blue dasher, Pachydiplax longipennis June 6, 2007.

I'm not exactly sure what this one is. It could be a blue morph female powdered dancer, or a female blue-fronted dancer. June 6, 2007.

Great blue skimmer, Libellula vibrans, June 9, 2007.

Possibly a rapids clubtail, Gomphus quadricolor. That is what was teased out at Bug Go here to see the pictures and comments there. June 9, 2007.

Blue-fronted dancer, Argia apicalis, June 16, 2007.

Blue-ringed dancer, Argia sedula, June 16, 2007.

American rubyspot, Hetaerina americana, June 16, 2007.

Eastern forktail, Ischnura verticalis, July 15, 2007.

Violet dancer, Argia fumipennis violacea, July 15 2007.

Eastern amberwing, Perithemis tenera, July 15, 2007.

Eastern Pondhawk,Erythemis simpliciollis (and two perilously close powdered dancers!) July 15, 2007.

I really not sure what this one is. My guess is that it is a female green darner laying eggs, although the riverine habitat seems somewhat strange. Any thoughts on this one? July 15, 2007.

Dusky dancer, Argia translata, July 15, 2007.

Twelve-spotted skimmer, Libellula pulchella, July 24, 2007.

Widow skimmer, Libellula luctuosa, July 24, 2007.

Blue-tipped dancer, Argia tibialis, July 27, 2007.

Fragile forktail, Ischnura posita, August 4, 2007.

Black-shouldered spinyleg, Dromogomphus spinosus, August 26, 2007.

Arrow clubtail, Stylurus spiniceps? September 21, 2007.

Fawn darner, Boyeria vinosa, September 30, 2007.

And finally, while I was watching our fish swim in our water garden, this female darner, which I'm guessing is a shadow darner, came to visit our backyard.

Shadow darner, Aeshna umbrosa, October 26, 2007.

Impression of a Great Blue Heron

March 22nd, Columbus, Ohio, along the Olentangy River.


Thursday, March 27, 2008

Sanibel, Florida- Island of the Fish Hawk

My first bird of the Florida trip? A boat tailed grackle at the Punta Gorda airport. The second? One that would capture my interest for quite some time, the Fish Hawk or Osprey, Pandion haliaetus. Parking at the condo, sick as a dog, I walked around to the back to a small concrete dock overlooking a tidal canal built for pleasure boats. Down the canal on the far side was perched an osprey, ripping into its meal, a black and white fish called a sheepshead, or Archosargus probatocephalus.

The osprey drew the attention of a little blue heron and ring-billed gull. Wow, what a cool bird I thought to myself, I wonder if we'll see any more?
Sure enough, only an hour later, we made our way to the beach. I put the long lens on the camera before heading out, hoping to get some shore bird images. I wasn't disappointed. And from the east came a fantastic osprey clinging to another sheepshead with its huge talons.
The next morning I went on my photo scouting mission of the island, even though I was sick as ever with a fever hovering around 101. I pulled into the island lighthouse parking area, and this nest platform towered above everything except the lighthouse. An osprey nest, quite a piece of construction.
And as I walked out on the fishing pier near the parking lot, I noticed these pro photographers with their Nikons pointed at the nest. I didn't have time to stick around and wait for the osprey, but after looking at the shot above more closely, I'm sure they were waiting for good shots of a male returning to the nest with a big fat fish, possibly feeding it to juveniles below the mom. In the field, I couldn't see the sitting mother, only when I got back and examined the photo more closely did she pop out at me. Yes, the picture below is the same exact photo as the one above, just cropped to ~%100. The clarity of the crop really demonstrates just how sharp Canon's 400 5.6L lens really is.

And the next day, still sicker than a dog, another osprey decided to give me one of the best photographic opportunities I've had. Unfortunately it didn't quite turn out like I wanted it to- with several blurry images and no fish for the osprey. But boy was it cool watching this bird dive down into the canal only about 20 feet from where I was watching from my plastic green lawn chair, again, sicker than a dog. (Pardon the expression, dog lovers!)

This bird paused for a moment, after adjusting its wings, and all of the sudden, WHAM!

No fish this time!


One Winged Fly Pollinates a Crocus

Check out the tiny pollen grains on the feet of this fly! From our front yard, taken yesterday during my lunch break.


Tuesday, March 25, 2008

The Final HDR Image- Sanibel Sunrise

And here is my final HDR image, created from the five images that I posted yesterday.

Pretty cool, isn't it? Notice how the people walking on the beach have been mostly removed from the final image. The software isn't perfect, as you can still see a their faint outline, also called ghosting. Still, without a tripod, and only balancing the camera on a railing, the Photomatix software did a fairly good job aligning the images. The Australian pine tree in the upper left was waving in the breeze, and in the final image, it looks as if I took this shot using a long exposure with motion blur.

The Australian pine (Casuarina equisetifolia) is a nasty invasive in Florida. There are so many of these trees there, that most visitors would just pass them off as an interesting part of the native flora. But they are a non-native invasive, and they grow quickly, replacing native dune vegetation. I first had experience with this plant when I was traveling around Australia in 1999 with Hiram College.

So, have you tried to create your first HDR image? It can be addicting--beware. I have a great guide called the HDRI handbook that I'm reading now, and it comes with software and image demonstrations. I found it in the catalog in the Columbus Metropolitan Library, and to show you how popular HDR is becoming, I had to wait three months before it became available. Who knows, future cameras may be engineered to take pictures without any post-processing to create these incredible images. For now, it takes a little bit of work, but I think the final results are worth it. Just another tool in the bag of the nature photographer.

Update: After Gale suggested I clone out the sunspot, I gave it my best shot using I am by no means an expert, but my cloning doesn't look all that bad! Now if I had photoshop...just think of the possibilities!


How to Create Fantastic Digital Images that Will Wow Your Friends

Notice anything interesting about this group of photos? I took them in succession, but at different exposure values using the exposure compensation feature with my Canon Digital Rebel XTI. The first image is two "stops" underexposed, the second is one stop underexposed, the third image is what the camera's computer thought was an ideal exposure for this scene, and the fourth and fifth images were overexposed by one and two stops, respectively.

The bottom line is that before digital photography, you had to choose one exposure and stick with it. Especially when using slide film. Which image would you have chosen to best represent the scene? More detail in the sky, or more detail in the plants in the foreground?

The bottom line today is that with digital imaging, you don't have to make this choice anymore. There's a technology, and an art really, known as HDR imaging that solves this age old problem and really puts digital photography over the top.

How did I found out about HDR? Upon joining FLICKR last fall, I was noticing some incredibly interesting images that looked like they were taken in real life, but had the lighting and look of computer animation. Images like this one and this one.

After doing some research, I found out that these fantastical looking images were called HDR, or high dynamic range images. These images, are in fact, a compilation of differentially exposed digital camera photographs all compiled into one image, in order to fully express the range of dark and light tones in a scene. Dynamic range is simply the difference between the lightest light and the darkest dark in a scene. Today's digital cameras don't capture a very wide dynamic range (neither did slide film, print film's range was slightly wider).

Have you ever noticed that your camera can't capture a sunset very well? Even though you might see color in the foreground of the scene you are viewing, the camera isn't able to pick that up. Or if your camera sees the foreground, then the sunset is washed out and really bright? Let's look closer at the first and the last image.

High dynamic range imaging looks to eliminate that problem that I have so crudely illustrated above. The goal is to present an image that more accurately represents what the eye sees rather than the camera sensor. After putting together an HDR image, you go through a process called tone mapping, and voila, you've got a pretty darn cool looking image.

And producing a high dynamic range is quite easy. Making it look really good is something that I'm still trying to figure out. I have seen some incredibly realistic looking HDR landscape images that don't look fantastical or computer generated.

There are several free downloadable software packages out there to get you started on the HDR path. I've been using Photomatix. What else do you need? Well, a digital camera with some type of exposure compensation (most Canon cameras have this, even the bottom of the line models), and preferably a tripod, but this is optional. I didn't use a tripod to capture the above images, and the Photomatix software can align a series of images for you if you shoot with a steady hand. It even has a feature to remove "ghosting" from the images, usually things like moving people, which certainly was helpful for me in this beach scene of Sanibel Island.

So, you're probably thinking, "OK, I'm ready to see the final product". Well, for that, I might draw this out just a little bit longer! I'll post my final image tomorrow. But for now, try going outside and taking a few image series, download Photomatix, and give HDR a try!


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