This is one of those goofy photos you take when you want to check in on the performance of a new lens or camera. It's not going in the portfolio. Why did I take it? Because I wanted to see how a particular lens worked on a new-ish camera and with new lens profiles supplied with the upgrade to Lightroom 4.4.
I'll back up. I bought a Sigma 10 to 20mm f4.5-5.6 lens last year to use on an assignment photographing a new Whole Foods store. My primary camera at the time was a Sony a77 and while the 16-50mm lens was great for most stuff I wanted something with a bit wider angle of view. I researched the possible options and flipped a coin. The Sigma won. While the 16-50mm 2.8 DT lens was fully corrected for vignetting and geometric distortion by in camera profiles none were available either in the camera or in LR for the lens at that time. On the shots I took with the lens I added time to my post production routine to mess around with the edges and corners in DXO software. The results were fine for the project at hand. Not quite as good a performance as the 16-50mm but certainly very acceptable.
I was working in the latest ish of Lightroom a few days ago when I started looking to see if there were any new profiles for lenses I owned. I found profiles for the two Sigma/Nex lenses I recently bought, the 19mm and the 30mm. I kept looking and also found a profile for the Sigma 10-20mm.
I like the two primes and I was curious to see if the Sigma 10-20mm, when combined with the amazing sensor in the Nex-7 and supplemented with the correction in LR, would have much improved imaging characteristics over the uncorrected performance last summer on the a77 DSLT, fixed mirror camera.
This building, under construction, provided a nice range of lines and textures. I thought it would be a good test. I used the lens with an LA-EA1 adapter, which has no mirror, only contacts for electronic information and primitive AF. I decided to use manual focus and focus peaking instead.
The Nex-7 has a very high performance sensor with high sharpness. I'm very, very happy with the performance of the combined camera hardware and Lightroom corrections for this lens.
The image just above is of painted plywood barriers that surround the construction project. I thought it was a nice test of the lens's ability to render texture and a pleasing rendering of the saturated green paint.
As usual, performance parameters of modern cameras and lenses are moving targets which are influenced and changed by the influence of software driven corrections. It pays to check in frequently to see if some part of your imaging system has been improved and may provide increased performance metrics without having to upgrade.
Having done this test I'll be less reticent to use the combination for architectural projects in the future. Have I mentioned just how much I like the Sony Nex 7?