Thursday, November 26, 2009

Quick Review: Canon 85mm f1.8 USM

Specifications at a glance:

Focal Length: 85mm (110mm APS-H, 136mm APS-C)
Dimensions: 2.8 by 3 inches
Weight: 15 ounces
Maximum aperture: f1.8
Minimum aperture: f22
Diaphragm Blades: 8
Lens Elements: 9 elements, 7 groups
Front element: non-extending, non-rotating
Autofocus Mechanism: Ring USM
Closest focus: 2.8 feet
Maximum magnification: 0.13x life size
Filter: 58mm

For more on the ratings system, click here.

Background:
Released in 1992, Canon's 85mm f1.8 USM lens is one of the oldest in Canon's lineup. While it may be an oldie, it's definitely a goody. In any debate of canon's best non “L” lenses, this one is sure to be brought up. With its fast aperture, USM motor, and modest price tag, this lens was designed for low light, sports, and portrait shooters on a budget. Shooting indoor sports court side is exactly why I bought this lens almost a year ago. Unfortunately, it gave the dreaded “ERR 99” and refused to autofocus about half the time on my old 300D/Digital Rebel, despite working perfectly on my newer 30D. I sent it back, which, due to B&H Photo's generous policy, was no hassle at all. Below is a brief review of the lens though analyzing some of my old pictures.

Optics: 4
Optically, this lens is a mixed bag, especially wide open. Even at f1.8, the center is sharp. Unfortunately, as one moves out, the sharpness falls off dramatically. On my 1.6x crop EOS 30D, the sharpness falloff starts about ¾ way out from the center. On a full frame camera, things in the corners must be pretty mushy wide open. Stopping down will improve sharpness across the frame. At f2.8, the center moves from sharp to razor sharp and the sharpness falloff starts to extend out further to the side of the frame. Stopping down to f4 yields virtually no improvement in the center, but the outer parts of the image continue to improve a bit. Unfortunately, the corners will never catch up to the center no matter how much you stop down. Now this may seem bad, but is it really? No, definitely not. This lens is not designed as a landscape/architectural lens where corner to corner sharpness is a must. The 85mm f1.8 USM is a portrait/telephoto/low light optic where, chances are, the subject will be in the center of the frame, where sharpness is good to start with. Chances are that, if used in its intended purpose, the soft corners of the lens won't matter anyway.

Autofocus Performance: 5
Armed with Canon's USM motor, the 85 f1.8 USM is a speed demon. Autofocus is virtually instantaneous, accurate, and to boot, just about inaudible. Needless to say, use of this lens won't be causing any heads to turn (the slap of the shutter will, though). However, be warned! With a maximum aperture of f1.8, the field of view will be razor thin the closer you are to your subject, so focus carefully. So if your images are out of focus, it may be your fault, not the lens's. Example: you do a close up portrait and focus on the end of your subject's nose. The end of the nose will be sharp but the eyes may be slightly blurry. You must focus precisely with such a fast lens. Fortunately, in well lit situations, you can stop down to f2.8 or more to achieve greater depth of field and room for error with focus.

Build/Mechanics: 4
The 85mm f1.8 USM lens is solidly built, especially considering its price point. The mount it metal and the rest of the lens externals are high quality plastics. The lens has a very dense feel about it. Shake it and there's no rattling whatsoever. The lens is inner focusing, which means that the front element does not extend or rotate during autofocus as the lens racks from macro to infinity. The focus ring is rubberized, well textured, and gives a very comfortable feel to it. Because the lens has a USM motor, the focus ring does not turn during autofocus and autofocus can be overridden by simply turning the ring at any time without the need to flip any switches. In operation, on my lens, the focus ring seemed a little snug in movement. Still, snug is better for manual focusing than sloppy. The lens takes 58mm filters.

Value: 5
This lens packs a lot of performance into a cheap package. It was selling for around $300 when I bought it and, with all the price increases, is now knocking on the door of $400. Still, it's a great value, especially considering it has the USM motor. With its excellent optics, USM motor, and build, this is a pro quality lens at a consumer grade price. If you choose to buy, you're putting your money to good use as this lens will deliver the goods every time.

Conclusion: 4.5
As a short telephoto prime lens, the Canon 85mm f1.8 USM is not a general purpose optic, it is designed for low light and/or portrait shooting. When used to its intended purpose, the lens performs admirably. Images are sharp in the center (where the action should be), autofocus is top notch, and the build is good for a consumer grade lens. On top of all that, despite the ridiculous price increases, it is still a great value considering the competition. If you own a full frame or APS-H camera and want a lens to shoot indoor sports or portraits, just go out and buy one. APS-C croppers, the story might be different for you. If you're looking to do portraits, no problem, move or have your subject move. If your game is indoor sports, one of the Canon's 50mm primes may be the better choice if you're shooting court side, as the 85mm essentially becomes 136mm. Still, crop factor aside, the 85mm f1.8 USM is a lot of fun to use, as it literally opens up new worlds in the dark.

The Ratings System

As I continue to add lens reviews, this is the rating system I will be using for the gear I test.

1 (poor)-you've bought a piece of junk
2 (below average)
3 (average)-you get what you pay for
4 (good)
5 (excellent)- among the best out there

These are the four basic areas where I will be examining the lenses:

Optics (more or less in-depth depending on how long I have the lens)
Autofocus operation (speed, accuracy)
Build/Mechanics
Value

Monday, November 9, 2009

High Marks for Canon's New EOS 7D

Digital Photography Review (DPR), possibly the web's foremost camera review site, just completed an in-depth review of Canon's new EOS 7D. While the camera's many new features (new AF system, weather sealing, and new flash system) all looked great, the adition of an 18Mp sensor left a lot of people shaking their heads in disbelief.

When Canon launched its 15Mp EOS 50D in 2008, it was found to be noisier than the old 40D, released a year before. Much of the blame was put on the smaller pixels of the new camera. Aparrently, the pixel density vs. noise limit had been reached, especially considering how other manufacturers held their pixel counts steady since the 50D regression. A lot of people were hoping for a new Canon digital SLR in the 10-12Mp range. Instead, they got the 18Mp 7D. Needless to say, a lot of people expected the 7D to be even worse.

However, what DPR found was a bit of a surprise. The 7D was not only easily better than the 50D at high ISO, but it even looks better than its chief competitior, the Nikon D300s. The image quality plus the dramatically improved features will undoubtedly give Canon shooters something to cheer about.

For more information on the 7D


Thursday, November 5, 2009

Rejoice! Standard Time returns!

Daylight Savings Time is gone and Standard Time (is it standard, it only lasts for just over 4 months) returns, which means good news for astronomers/astrophotographers.

The calendar says November, but the sky still says August, at dusk at least. With the advent of Standard Time returning, we will be treated to one last, brief peek at the summer constellations. So go out just as it gets dark to see the Teapot diving in the Southwestern sky. If you live in a dark area, you can still see the Milky Way, looking like steam, coming out of the Teapot's spout and rising up into Aquila and then through Cygnus. If the visual sight was not enough, a telescope at low power will reveal a swath of nebulae and star clusters, both open and globular, among the starry arch that is the Milky Way. Overhead and to the West, Hercules (two wonderful globulars) and Bootes (globular and double stars highlighted by Izar, which looks green and gold) are still visible. Since the summer constellations are still visible, all we need now is the warm weather!

And by the way, here's a re-edited M25.

Tuesday, November 3, 2009

New Stuff: September 2009 Astrophotos

Some good wide angle shots and three all new deep sky stunners.

Eagle Nebula reshoot. 1.5 hours total exposure, more than double last month's, to which I added more frames and stacked again. The difference in detail is clear.

The M103 open cluster.


The Little Dumbbell Nebula.


Full Moon setting over foggy field just before dawn.


Old Moon through the ED80.


Old Moon and Venus at Dawn.


Waning Crescent and Venus early in the morning.


Overexposed Moon ands Jupiter rising.