September 13th, 2005:

After much pondering and internal debate, I picked up a cheapo “Sigma 18-50mm f/3.5-5.6 DC Lens”:http://sigmaphoto.com/lenses/lenses_all_details.asp?id=3286&navigator=6 today for $109. I debated a lot between it and the “Sigma 18-125mm f/3.5-5.6 ASP IF DC”:http://sigmaphoto.com/lenses/lenses_all_details.asp?id=3287&navigator=6 and I’m still not 100% certain I made the right choice.

I want a lens that will make decent images in most situations while remaining light weight and minimizing the need to change lenses. This will then allow me to “just shoot” so that I’ll be inclined to make more photographs. I get so much practice on the technical aspects of photography that I often forget that the creative side needs practice too. So, with this lens, I’m hoping to get that practice.

So, starting tomorrow, I’m going to keep the camera out and ready as often as possible. Feel free to offer themes, ideas, or concepts for me to attempt to photograph.

When looking for this lens, quality wasn’t *that* important to me, but I didn’t want it to be terrible. Most sites that rate lenses rate it *very* low, but all of the images I’d seen taken with it did not seem to be all that bad. My own tests show that it is a fairly decent lens, especially considering the price.

At 50mm and f/8, I could not tell its images apart from my prime Nikkor 50mm f/1.8. I know that sounds absurd, since the 50mm prime is one of the sharpest lenses Nikon makes, but from my unscientific method (use a tripod and take two photographs of the exact same scene from the same spot with the same camera and same settings. When I stopped down to f/3.5 (the max aperture of the Sigma at 50mm) you can just barely see a difference between the two, not so much in sharpness but in contrast.

The next time I’m at my Dad’s place, I’ll put it up against his Nikon 18-70mm f/3.5-4.5G D70 kit lens at multiple focal lengths. If there’s interest in seeing these comparisons, I’d be happy to post the images with explanations and 100% view crops.

four tall

(Flickr | Enlarge)

“Kristen”:http://livejournal.com/~chiquitabunny/, Jen, “Stefanie”:http://livejournal.com/~kamoriaha/, and Alissa from a photoshoot about 2 weeks ago (yes, I am THAT far behind).

Your comments and suggestions are appreciated, as always.

Apparently, scientists have been able to determine the “exact time and location”:http://www.newscientistspace.com/article.ns?id=dn7888 during which Ansel Adams took a certain famous photograph of his. Furthermore, they’ve determined that, this fall, the exact same celestial conditions will be present and a team of them has decided to go recreate his photograph.

bq. We know that the Moon will be in the same place, the mountains will be in the same place and we’ll be in the same place. Unfortunately, we can’t say the same about the clouds.

I’m anxious to see the reults.

( via “shebreathes”:http://www.livejournal.com/users/shebreathes/95521.html )

In looking for reviews and recommendations for a cheap, wide range (greater than 5x) zoom lens I found this gem of information in regard to the Sigma 18-50 f/3.5-5.6 DC lens:

bq. The Sigma is designed for Digital SLR. So its image circle falls neatly inside my Canon DRebel’s APS sized sensor. Therefore an 18mm is really an 18mm.

Let’s break this down a bit. First, yes, the image circle of Sigma DC lenses are designed to cover a APS sized sensor and will not cover a full-frame 35mm sensor. And, 18mm is ALWAYS 18mm. However, what this person is talking about is effective focal length (in regard to field of view) when compared to a 35mm film camera. Just because the image circle produces by a DC lens is smaller, it is still an 18mm lens. Therefore, with a smaller image circle, there is LESS image. That doesn’t mean that the image in the non-DC lens would be reduced to fit in the smaller circle. This CAN be done by shortening the length of the lens. But that would, of course, decrease the focal length. Therefore, in regard to field of view, a multiplier still needs to be considered on DC lenses and, to use his improper terminology, an 18mm DC lens is NOT an 18mm lens on his camera… it’s a 28mm lens just like like a regular non-DC 18mm lens would be and just like any focusing plane of glass held 18mm in front of his sensor would be.

Misinformation sucks. Had I bought this lens assuming I would get the field of view equivalent of an 18mm lens on a 35mm camera, I would have been quite disappointed since I would need a 12mm lens to achieve that and they run 5-10x the cost of this cheap lens.