Saturday, May 30, 2009

Willow Flycatcher

Adult male Willow Flycatcher, Franklin Twp, NJ in May. Several areas in Franklin hold them, at least in part because Franklin Twp makes some effort to keep a fair amount of open space. Some of these grasslands are invaluable for declining birds like Grasshopper Sparrow and Bobolink, although Willow Flycatcher is a little more versatile and not under quite so much pressure as those two specialists.

Tuesday, May 19, 2009

Golden-winged Warbler

Adult male, NY in May. Rapidly declining under the twin pressure of habitat loss and hybridization with the more dominant Blue-winged Warbler, there are still a few pockets of this species to be found in the north-east.

Sunday, April 26, 2009

Bay-breasted Warbler

Very early but not totally unprecedented, this adult male Bay-breasted Warbler was seen on April 26th in Central Park. This species is more commonly associated with being found in the warbler weather of May 10th or later.

Sunday, April 12, 2009

Wednesday, November 5, 2008

Canon hits the wall ?

The most recent review of the Canon 50D by dpreview.com suggests that the successor to the 40D hasn't eked much more resolution out of the images than its predecessor.

Ever since the introduction of the first "prosumer" digital SLR with the D30, Canon have done an epic job of increasing pixel count (and therefore resolution) of this line of cameras while keeping the noise level down:

D30, 3.1 megapixel, 10.1 micron pixels, [full-frame 7.9 mpix]
D60, 6.3 megapixel, 7.4 micron pixels, [full-frame 16.1 mpix]
10D, 6.3 megapixel, 7.4 micron pixels, [full-frame 16.1 mpix]
20D, 8.2 megapixel, 6.5 micron pixels, [full-frame 21.0 mpix]
30D, 8.2 megapixel, 6.5 micron pixels, [full-frame 21.0 mpix]
40D, 10.1 megapixel, 5.7 micron pixels, [full-frame 25.9 mpix]
50D, 15.1 megapixel, 4.7 micron pixels, [full-frame 38.7 mpix]

(all the chip sizes are essentially identical for this series of cameras)
The full-frame values are what you'd get in a full-35mm-size chip of the same pixel density.

The review suggest that both resolution and noise levels on the 50D are no better (or, in the case of noise level, worse than) the 40D. Have we finally hit the limitations of resolution with these Bayer matrix sensors ?

And for those who are wondering why I care: here's an explanation.
To oversimplify: pixel density is more relevant for telephoto shooters, while the total number of pixels is more relevant for people that can fill the frame with their subject.

Saturday, November 1, 2008

Wednesday, September 3, 2008

Canon 800mm f5.6

For a modest $11,599 + tax B+H is willing to sell you a Canon EF 800mm f5.6L IS

Despite the price tag it's quite a tempting lens. For one thing it's also a lot lighter than the 600mm f4L IS lens, while being around the same size (9.9 lbs vs 11.8 lbs), has an intrinsic focal length close to the 600mm + 1.4x teleconverter, and will be shockingly sharp without the converter or be an 1,040mm f8 lens with it.

Downside ? The minimum focus distance is 19.7 ft, so that's an 0.14x magnification at the closest range. The values for the 600mm f4 are 18.2 ft and 0.12x. So while you get a little extra magnification at closest distance you need to step back about a foot and a half. Of course, if you never get to within 20 feet of your subject this point is largely moot and the 800mm looks like an excellent option, modulo the price.

See Canon's own comparison between 500/4, 600/4 and 800/5.6.