Rich Ditch's Photography Blog

January 24, 2010

Anna’s Hummingbird at close range

Filed under: Birds, favorite places, Gilbert Water Ranch — richditch @ 1:31 pm
Anna's Hummingbird

Anna's Hummingbird

There’s a preposterous statement in the February 2010 issue of Popular Photography that is sure to make some novice photographers disappointed, especially if they actually use the info for a purchase decision. This issue is devoted to lenses, and the statement that stopped me in my tracks is on page 70 in “How to buy a lens” by Don Richards. The article separates lenses into various categories based primarily on focal length and then lists Pros and Cons for each grouping. Category 7 is Supertele, defined as “400mm and up (full frame), 300mm and up (APS-C), 200mm and up (Four Thirds).

Here’s what set me off:

Pros: For a hummingbird at a hundred paces, only these lenses will do.

Good luck getting any usable photo of any hummingbird at 100 paces with any lens!

Hummingbirds are tiny: this Anna’s Hummingbird photographed at the Gilbert Water Ranch is listed at 3.5-4 inches (9-10cm) in Hummingbirds of North America by Sheri Williamson. This size is typical of hummingbirds, including the well known Ruby-throated of the eastern U.S. This includes the bill, by the way, which can be a significant percentage of the total.

The laws of optics give us a simple equation:

(image size)/(object size) = (image distance)/(object distance)

or (image size) = (object size) x (image distance)/(object distance)

So, let’s do the math:

Object size = 10 cm = 100 mm

Object distance = 100 paces = 250 feet (from Pop Photo’s “Pro” at 2.5 feet per step) = 3000 inches = 76,200 mm

Image distance = focal length = 300 mm (from Pop Photo’s category)

Therefore, Image Size = (100) x (300) / (76,200) mm = 0.39 mm.

That’s right: the image of a 4 inch long hummingbird at 100 paces through a 300mm “supertele” makes an image less than half a millimeter long on the sensor in the camera. The sensor in my Nikon D200 measures 23.6mm wide by 15.8mm high, so our hummingbird would only use 2.5% of the short dimension of the full frame.

The reality of photographing hummingbirds is that you need to get close to them because they are so small. For the Anna’s shown here I was using 600mm (my 300mm plus 2x converter). I was probably within 15 feet of the bird. And I cropped this image to 56% of total just to make the hummingbird larger in the frame.

Yes, long focal length lenses are important in bird photography, but getting close to the subject is more important. Don’t expect that buying a longer lens will give you mastery over small subjects. And don’t think you can make up for optical reach and close shooting by excessive cropping.

Nikon D200, 300/2.8 lens plus TC20E 2x converter (600mm effective focal length), tripod, ISO 400, 1/430th second at f/8, spot meter, cropped to 58% of frame, Jan 20, 2010.

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2 Comments »

  1. That’s a great close-up! I’ve found that another way to get close to hummingbirds is by using nectar feeder and waiting nearby. I read about those Perky Pet Top Fill feeders. They seem to be the easiest on the market to fill and clean.

    Comment by Karen — April 4, 2010 @ 3:37 pm

  2. Yes, a lot of the hummingbird photos we see have been taken at or near feeding stations, and that is definitely a way to make things easier.

    But my preference has always been for birds I encounter away from feeders or other setups. My primary enjoyment comes from seeing and photographing birds where they chose to be and not where the photographer entices them to be.

    Comment by richditch — April 5, 2010 @ 1:01 pm


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