Quick photo shoot at work

One of my colleagues at DAMTP needed some photos to demonstrate her new image processing algorithm. So we scheduled half an hour before lunch and went out into the light rain with a camera and a reflector. I sometimes carry the reflector with me when photographing, but I rarely use it. This time, since there were four of us, I could get someone to hold it for me. I did a few shots with and without the reflector to compare, and it was interesting to see how much difference it made for the shadows when we were standing next to the building, under the roof.

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Ellese Cotterill was first out since she had to do supervisions at 12. This meant she had to endure me adjusting the camera settings. I consciously avoided shooting at wide open (f/1.8) since at this distance that would have meant that only her eyes were in focus. In the EXIF information of the RAW file I could read that the focusing distance was 1.26 metre. This meant that at f/4 I had 5 cm depth of field. If I had shot it at f/1.8 then the depth of field would have been 2 cm. Had I instead gone all the way up to f/8 then I would have had 10 cm depth of field, which could have been one possibility. I did not want any movement in the photo so did 1/400 seconds exposure, and ended up with ISO 800 which is well within my ISO-comfort zone.
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Joana Grah, who was the one that needed a photo. I am curious to see if this photo works to test her algorithm. Will see if I can get her to write a little blurb about what it does. The one thing I knew was that she wanted some filled circles visible.

Update: The photo above is now featured in Joana Grah’s paper “Regularization with Sparse Vector Fields: From Image Compression to TV-type Reconstruction”, available on the arXive.org website (see Figure 4).

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Veronica Corona. I liked this photo with her expression. Here I had stepped back a bit to not just get a head-shot.

If you are interested in some tips on how to use a reflector, then have a look at this YouTube video (from the SLR Lounge) showing how to put it to good use on a sunny day.

I have a bit of a backlog with photos, so stay tuned. There will be another dress rehearsal, and a fashion photo shoot coming in the next few days.

– Johannes

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One Comment

  1. Simone
    December 3, 2014
    Reply

    You are such a good photographer. I tweet your photos now and then. If you have any nice Cambridge photo or postdoc ones, feel free to contact me. I am still working on the opda website and could do with a few more.

    Thank you

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