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Author | Topic: Road Trip - Dragonflies - Photography - Geology | |||||||||||||||||||||||||||||||||||||||||||
Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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Well, not completely different, but a species I have never posted here before. Hagenius brevistylus is one of the largest dragonflies in North America and it preys primarily on other dragonflies, hence the common name Dragon Hunter. It is always on my target list of species I want to photograph whenever I am in the eastern U.S. I found this female on the Middle Fork of the Stones River near Murfreesboro, TN.
This species is in the family Gomphidea or Clubtails and they are mostly stream specialists. Normally they like to land on stones in the stream or on leaf surfaces of streamside vegetation, but Hagenius prefers the tips of twigs. Note the use of the hind femur and tibia to grasp the perch that is typical for this species. As far as I know, no other species grasps the perch like this.
The primary reason I went to Tennessee was to meet some friends and search for a dragonfly that was seen by one of them a few years ago. It was the largest dragonfly he had ever seen in a 55-year career of studying them, so he knew it was an undescribed species and unknown to science. We spent most of a week in southern TN near the Alabama border looking for this critter. We saw it a number of times, always flying away from us (after it had passed us), but we never got a close look or a chance to swing a net. A second team took over when we left and they even tried mist nets in which the caught a number of other large species but not the target. My friend who originally made the first observation was suffering from a lower back disk problem and another friend got a bad leg cramp on the 3rd night and the next day it was badly swollen and painful. We ended up taking him to the ER because we were worried about blood clots. He was clear but it put him out of commission for the rest of the trip. After a few days it turned all black and blue and yesterday he told me it is still quite painful. It just seemed to be an ill-fated trip. It was frustrating to not get any photos or specimens and we were unable to locate a likely nymph habitat either. We'll get it next year.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy |
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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The canyons cut into the Permian White Rim Sandstone surrounding Island in the Sky in Canyonlands National Park have this general pattern. They end in what you might call clusters of blind canyons. It looks obvious that they were not cut simply by a river flowing through. The ones pictured here are associated with the Green River that can be seen in places.
It looks like there are small dry streams that would flow to the head of each canyon and then form a waterfall dropping into the canyon. Could it be that these canyons were cut by ice and snow meltwater during the last ice age and that further erosion in the present is mostly limited to flash floods from thunderstorms?
The Green and Colorado rivers meet south of here and the Colorado has similar canyons on its eastern side of Island in the Sky. Edited by Tanypteryx, : spellingWhat if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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I spent a couple hours out at my favorite pond this morning testing a custom fill flash diffuser with bright sun giving me some backlight to bring out the fine hairs.
If there is a better way to spend a morning, I haven't found it. This is a male Sympetrum illotum, common name Cardinal Meadowhawk. The red on the abdomen of this species is so saturated that I have to desaturate it to keep fine details.
Edited by Tanypteryx, : No reason given.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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I'm picking my longest time dragonfly friend (met in 1983 and have been traveling together ever since) at the Portland airport Friday night and we are headed for a dragonfly society meeting in Utah. Two weeks of two old guys rocking out from one aquatic habitat to the next. A couple days with some others doing a dragonfly blitz at Zion National Park, then main meeting and field trips around Salt Lake City.
It looks like we will have some good presentations of scientific research at our one day main meeting and lots of good habitats to explore the rest of the time. It is gratifying to see how many students we have in the younger generations who are using Odonates as their research subjects. I am lucky to still have many friends that I've known for more than 25 years who are coming to our annual and regional meetings.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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We had a fun trip to Utah and a great meeting. We participated in a dragonfly survey at Zion National Park and collected and photographed in some new habitats that we had not explored before. I was familiar with all the species we saw but we also collected nymphs and got eggs of several species that we will try and rear out to adults. My friend who I was traveling with is the North American authority on dragonfly nymphs and is finishing up a book on all the species. I was able to take him to a location in SE Oregon where we collected eggs from a species that has never had the nymph described, so if we are successful at rearing it, he will be able to include it in the book. He is missing only one other species that hopefully we can get before the book goes to press.
On the last leg of the trip we visited Todd Lake in the Cascade mountains, where I caught my first dragonfly when I was a boy. A couple years later I discovered the second known population of Tanypteryx hageni. Now we have documented more than 200 distinct populations scattered from far north in British Columbia to south in Yosemite National Park in the Sierras.
Tanypteryx hageni along with some of the other 10 species that make up the family Petaluridae live in burrows when they are nymphs. They construct the burrows in hillside boggy seeps and prey on small animals that venture too close to the opening. They spend five years as a nymph. The burrows of a mature nymph as in these shots is about 10mm across and can be 300mm deep.
This is the exuviae or cast off skin that is left behind when the dragonfly emerges and metamorphoses into an adult.
This is an adult male. They are attracted to light colored objects like rocks or weathered wood and use them as the center of their territory that they will defend against any interlopers.
I really love the pattern of light spots on the dorsal abdomen.
This is a copulating pair.
This is the view of Todd Lake and Mt Bachelor from the nymphal habitat.
EnjoyWhat if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0 |
A sweet image of Rhionaeshna multicolor, well done!
I am not sure how to embed your image. fkickr creates the db code for me. The closeups were all taken with a Nikon D700 and 200mm micro-nikkor, f36@1/30, ISO 400, diffused flash.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0 |
This was shot as aiming practice using a D500, 300 mm F/4 PF with 1.4 TC at 1/2000, ISO 900, f/8. Were you using manual or auto focus? I have never been able to use auto-focus for flight shots.
I'm going to experiment with much higher f-stops and slower shutter speeds. I had the speed set for hummingbirds. Dragaonflies are my favourite insects by a mile. I have had fairly good luck shooting at a higher ISO ~2000-3200 and f20-f22. A bit of extra noise in flight shots is acceptable (to me). I experimented using a Better Beamer on my flash synchronized to high shutter speeds 1/2500-1/3000. It worked to stop the wings in a few shots but it turns out that I prefer shots with wings that are partially blurred by speed. ABE: One interesting thing to note, the dragonfly in your shot has its legs tucked up tight against the body in flight. When I first got interested in dragonflies as a kid the literature described their behavior in flight as using their legs as a basket to snare flying prey. High-speed photography showed that they actually capture prey with their mouths and then use their legs to manipulate it if needed. Photography also shows that they keep their head level with the horizon even when making high speed banked turns. Edited by Tanypteryx, : No reason given.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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The D500's new autofocus system is very, very good. I envy you that.
This one is at ISO 22800 (and f/8 and 1/2000 like the others). At that ISO I get shit if the subject isn't well lit but with a moderate amount of noise reduction in light room I get the above acceptable result in the sunlight. The subject looks great.
The 300 mm F/4 has a 1.4 meter closest focusing distance and keeps that with the 1.4 x teleconverter turning it into a 420mm so it becomes a sort of long range "macro" with very nice bokeh. I have run into several dragonfly photographers who use that lens successfully.
I like the idea of having an assisstant (a pretty one ) holding the flash as close as possible and use that to get a short burst of light. Funny you should mention that..... A German fellow named Georg Rppell used to shoot high-speed film (500 fps) of dragonfly behavior and he had a beautiful assistant we called the "Delicious Dagmar". I believe he is still shooting, but now with video.
The drawback (to me ) of the D500 is the "only" 21 Megapixies. I compare it to the D810 and figure the combination of the loss of pixies and the 1.5 crop of the D500 gives me a 1/3 improvement in "reach" (or pixels of subject when comparing the two cameras). I have a pair of D700s that are only 12 megapixels. I am considering a D810 both for the video capability and the pixel density for stacked photomicrography. Here are a couple of my early flight shots of male Aeshna palmata.
This is A. palmata in a high G turn with his head level and body at about 45 degrees.
One of the cool things about dragonflies is their ability to move all 4 wings independently using muscles attached to the wing bases. This is considered to be how all the first flying insects flew. All the other orders evolved a different method of moving the wings while Odonates retained the "primitive" musculature and evolved exquisitely fine flight control of their large wings. What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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How the heck did you keep it in frame if it was moving fast? That is what I am practicing to do and find it very hard. Luck Shooting lots of shots at the end of their patrol loop where they make tight turns.
I've been looking for an aiming device like "red dot" but there is another one that is just like a little gun sight that goes into the flash mount. I saw it a year or so ago but can't find the thing now. I don't see how that would make it any easier. The dragonfly is your target so you point the camera at it. Trying to point a laser at it isn't going to make it any easier, unless I am missing something.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0 |
Accuracy by volume! The broad side of a barn doesn't stand a chance.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0 |
"Spray and Pray" Manual focus cuts the count of my successful shots considerably. Shooting when they are hovering increases my odds a bit. That first shot (in Message 48) was taken with an old 70-180mm micro-nikkor at 180mm, f19 @ 1/500 ISO5000. As far as I know the 70-180 was the only true macro lens that would zoom while focused. I got it back in the '90s for my F5. The high G shot was with a Sigma 180mm macro +1.4TC, f25 @ 1/2000 ISO3200. This shot of a male Anax longipes from last summer in Pennsylvania was with a 200mm micro-nikkor, f20 @ 1/250, ISO1250. I only got a chance to shoot about a dozen shots because he stayed out of range most of the time.
There are some people out there who shoot Dragonfly Airshows far better than I do. The best I ever saw was a shot of a Pantela flavescens cop pair in flight with the wings frozen and everything in perfect focus. A boy has to have dreams........What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0 |
I don't get why higher resolution helps with focus stacking (something I want to try sometime). In my case it is primarily a desire to blow the final image up to a larger size. Stacking defeats the loss of depth of field in high magnification images and then adding more magnification resulting from smaller, tighter pixel density allows us a sharper view of smaller features. I would also love the benefit of blowing landscapes up to larger print sizes. My friend's nymph book deadline is the end of 2017. Once that is finished we are hoping to make a trip back to Bolivia. When we were there last in 2001 we were still shooting film and no video capability. We discovered two damselflies in the Polythoridae family, Polythore boliviana and Cora terminalis, that are the absolute most beautiful odonates we have ever seen. We want to get still shots but also hi-res video of them flying. At our age this may be our last tropical trip.
But I'm wondering if a D500 would be a better fit for you. It is faster focusingas and has a much higher frame rate than the 810. (too bad you aren't going to be through Vancouver or I'd let you try both). The D500 does sound like maybe it's what I need, but 500 is lower than 810 or 700 for that matter, so it can't possibly be as good. One of the reasons I bought (and love) the D700 is the low noise sensor, but it does seem that Nikon has greatly improved the noise profile of their sensors as they have reduced the size and increased the density of their pixels. I do worry about diffraction limiting the gains in resolution when shooting at small apertures. I have a D2x and I was quite disappointed at the loss of detail I suffered due to diffraction compared to my shots on film using the same lens. It seems there are always trade offs and sacrifices that come along the benefits as the technology evolves, not to mention the prices. I think I paid $450 for my first Nikon F.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0 |
I am heading back to Todd Lake to see if I can get some better photos of Tanypteryx, especially cop pairs.
Edited by Tanypteryx, : No reason given.What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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Tanypteryx writes:
Dude just go in the bathroom and take a selfie in the mirror like a normal person. I am heading back to Todd Lake to see if I can get some better photos of Tanypteryx What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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Tanypteryx Member Posts: 4443 From: Oregon, USA Joined: Member Rating: 5.0
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I don't want to see that in his bathroom. Just bugs doing it... please. Well, the excursion yesterday was interesting, but I didn't end up shooting any photos of Tanypteryx and the only cop pair flew high up into the trees as soon as they formed a wheel. The fellow who was driving showed up in a new Tesla. It is an amazing example of technology. The purpose of the trip was to capture some Tanypteryx females at Todd Lake to transplant to a seep near Portland. If they will oviposit in the new habitat we may be able to establish a new population. The nymph stage lasts 5 years, so the transplantation procedure will need to be repeated each of the next 5 years to have a thriving annual population. The Tesla driver owns the property with the seep and he placed two pairs under chickenwire domes in the habitat last night (we were only able to collect 2 females). This morning both pairs were gone and he did find 2 sets of wings, so some kind of small predator feasted on them last night. He is going to try again before the flight season is over, but I think it is a long shot that he will be able to establish a viable population.
bugs doing it... please. I will dig out some shots of other species doing it, but for now this is a shot of an Anax junius male that I was able to get close to the day before yesterday.
What if Eleanor Roosevelt had wings? -- Monty Python One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy
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