Public Lab Research note


More camera testing

by cfastie |

Read more: publiclab.org/n/9305


On Sunday at LEAFFEST Jeff continued the camera test by repeating Saturday's scene in different light (brighter shade under blue sky) and a new scene by the garden. In addition to photos from each webcam with two different Rosco filters, we also captured RGB photos and infrablue photos with two or three Powershots.

One of the infrablue Powershots, the Superblue G11, can save two different custom white balances. I took photos of the second scene with each white balance setting, but the G11 was capturing only camera raw files. When these were imported into Adobe Lightroom, they were displayed without applying the custom presets. But when I opened these raw files in IrfanView, the presets were applied. So the Canon raw files have the preset information embedded, but Lightroom does not use it. I saved as jpg from IrfanView to get the images below. The white balance tool in Lightroom was not able to recreate the white balance setting by clicking on the same gray card in the photo that was used to white balance the camera. Not even close.

LeaffestD40-223-55.jpg
The camera board with eight webcams with their IR block filters removed. A piece of Rosco filter covers the lens of seven of the cameras.

Scene1_RGB.jpg
The first scene on Sunday. Nikon D40.

Scene1_A810__74.jpg
The first scene on Sunday by the Powershot A810 with Rosco #74 filter.

LeaffestD40-223-69.jpg
The second scene with grass, Brussels sprouts, the gray elephant, and calibration cards. Each camera was connected in turn to the laptop.

Scene2_RGB.jpg
An RGB photo of the second scene taken by a Nikon D40.

Scene2_RGB_Card.jpg
Four different calibration/white balance cards were included in this scene.

G11_BG3_WB1_onGray_7992.jpg
The second scene by a Powershot G11 with BG3 filter which was white balanced on a gray card in the sun.

G11_GrayWB_NDVI.JPG
NDVI from the G11 photo above from the Fiji plugin. The NDVI values for grass and Brussels sprouts should probably be higher (more yellow or orange).

G11_BG3_WB2_onBlue_7987.jpg
The second scene by a Powershot G11 with BG3 filter which was white balanced on blue fabric in the shade under blue sky.

G11_blueWB_NDVI.JPG
NDVI from the G11 photo above from the Fiji plugin. The NDVI values for grass and Brussels sprouts should probably be lower (more yellow or orange).



near-infrared-camera vermont leaffest infragram infrablue infragram-conversion leaffest2013

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