Autumn Meadowhawks

Saturday, September 29th, 2007

Chase and Ben, ask your Dad what these two are doing.
Autoum Meadowhawk dragonflies mating in wheel position
Autumn Meadowhawk, Sympetrum vicinum, a.k.a. Yellow-Legged Meadowhawk
Ridgewood Reservoir, 2007-09-29


New York Skyline

Friday, September 28th, 2007

downtown Manhattan over the Hudson river

I’m not sure why, but you don’t see so many pictures of the downtown Manhattan skyline taken from New Jersey. For some reason all the movies like to shoot from Brooklyn or the South instead.

Connecticut Warbler

Friday, September 28th, 2007

I went back to Metrotech early this morning before work to see if the Connecticut Warbler was still around and it was (though once again the first sighting was a false alarm caused by a female Common Yellowthroat.) This time I brought my camera with me. The light wasn’t great, the bird was moving fast when it was visible, and I don’t have a clue about how to adjust the various wheels, knobs, and buttons to account for all this. Nonetheless I did manage one half-decent, clearly identifiable photo of the bird.

Olive-brown and yellow warbler with white eye ring

Adaptive Optics on the Cheap

Friday, September 28th, 2007

I can’t believe this actually works. Can the answer really be this simple and this cheap? Back when I was doing astronomy in grad school, some of my colleagues were spending huge amounts of time, money, and effort to create really fast adaptive optics systems that would bend mirrors just the right way to account for atmospheric noise. Instead can we really just take a bunch of pictures and paste them together in Photoshop?

Well maybe not quite that easy. The more technical release notes:

The camera works by recording the images produced by an adaptive optics front-end at high speed (20 frames per second or more). Software then checks each one to pick the sharpest ones. Many are still quite significantly smeared but a good percentage are unaffected. These are combined to produce the image that astronomers want. We call the technique “Lucky Imaging” because it depends on the chance fluctuations in the atmosphere sorting themselves out.

So they’re still using adaptive optics, but then applying this additional averaging filter to further improve the image. Apparently high speed cameras are also part of the equation so they can take more pictures closer together, which we couldn’t do 15 years ago. (Astronomical photography is harder than regular photography because you have so much less light to use.) Still if you could remove the need for adaptive optics completely, you’d really have something. Adaptive optics systems are still well beyond the reach of the amateur. Computers, CCDs, and Photoshop aren’t though.

#390 Connecticut Warbler at Metrotech

Friday, September 28th, 2007

I’ve gotten a lot of life birds in Prospect Park, Central Park, Jamaica Bay, and other sites around New York City; but despite working there for ten years, yesterday is the first time I got one in downtown Brooklyn, right in the middle of Metrotech. A Connecticut Warbler, the most elusive of our local warblers, was flitting around in some shrubbery right outside of Rogers Hall at Polytechnic University where I teach.

No pictures yet, but it looks a lot like a female Common Yellowthroat, one of which was also present just to confuse things. However the Connecticut Warbler has a more distinct eye ring and much more yellow all the way down its chest to the undertail coverts, not just on its throat. It usually has a hooded look to it, though that wasn’t as apparent on this individual, apparently a first winter female. Still the yellow was missing from the throat, exactly where you’d expect to find it on the Yellowthroat. This individual was also quite a bit fatter and rounder than the Yellowthroat.

Amazon Breaks Their Site

Wednesday, September 26th, 2007

Used to be you could surf Amazon completely without cookies. They’d feed you a cookie if you were naive enough to take it, but you didn’t have to accept it. You could still browse, add items to and remove items from your shopping cart, checkout, pay, and do anything else you wanted to do without any cookies at all. That was a very important characteristic given Amazon’s penchant for tracking users and data mining.

The Amazon site wasn’t completely RESTful–without a lot of JavaScript I don’t think any consumer site could be given both the browser vendors’ and the W3C’s failure to implement simple features like HTTP logout and forms that PUT and DELETE–but it did better than most.

However about a week or two ago something changed, and it now seems impossible to do more than browse without accepting their nutrition-free cookies. They seem to be going through a site-wide redesign. This is a definite step backwards. Given that they were already maintaining sessions (without cookies) before, I’m not sure if this will have a negative impact on their scalability. Nonetheless, it’s disappointing.