Sample photos from my Sigma 50-150mm F2.8 EX DC OS HSM lens

Started May 8, 2012 | Discussions thread
Regular MemberPosts: 497
Re: Not so good
In reply to gerry123, May 11, 2012

Hi Gerry and Jeff,

Since you guys have these lenses to test, would you mind printing out a real test chart and taking some more scientific test photos?

Here is the chart:

Good test conditions:

  • Brightly lit with diffuse (soft shadows lighting) - e.g. outdoors in the shade or on a cloudy day

  • No wind

  • Stick the lens test chart to a piece of wood, the side of a house, something stable, taped down totally flat. Clipboards work well.

Set up your camera:

  • Camera on a tripod, set up at least 6ft (2m) away from the chart, and, importantly, aimed straight at the chart , so that the chart is totally parallel with the camera's sensor.

  • Flash turned off, OS on the lens turned off (since you're on a tripod)*

  • Camera in Aperture priority, with enough light in the scene for:

  • low ISO, like 400 or less

  • high Shutter speed, like 1/500 or higher

  • (or just set it up in manual mode with similar settings instead of aperture priority)

Take test shots:

  • fill the viewfinder with the test chart the same way for each picture

  • focus manually on the test chart, using your live view to check that the focus is as sharp as possible.**

  • take multiple shots at apertures of 2.8, 4.0, 5.6, 8.0, and 11.0

  • take each one of these shots at 50mm, 70mm, 100mm, and 150mm (marked on the side of the lens)

  • end result is 20 images - one for each combination of five different apertures at four different focal lengths - if you have more than one shot for a certain combination, pick the best (sharpest) example for the final 20

* If you don't have a tripod, handheld shots with the OS turned on would work too.

** On a 550d, live view is accessed by the button just to the right of the viewfinder, on the back of the camera. You can then "zoom in" with the (+) and (-) buttons to check the focus.

** On a Sony a57, you can access live view by pressing the Finder/LCD button (to switch to viewing on the LCD). From there, you can zoom in and out using the (+) and (-) buttons.

Obviously this is a lot of work, but it would be awesome if one of you guys would do this

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