Re: Basic Setup Question

Posted by Gabriel Landini on Nov 17, 2010; 3:47pm
URL: http://imagej.273.s1.nabble.com/Basic-Setup-Question-tp3686410p3686414.html

On Wednesday 17 Nov 2010  15:18:19 you wrote:
> Not if you have a calibration card in each image:
> http://www.hawksphotovideo.co.uk/calibration_and_grey_cards/Lastolite_XpoBa
> lance_Notemaker_Calibration_38cm_15_1559
>
> That would allow to compensate for whatever bogus the camera is doing.

Hi Stephan,
If one can fit that in the frame yes that is a possibility to try and minimise
the autogain settings, but it is not straightforward when using a microscope
(and yes, webcams are being sold with ocular adaptors for microscopes). The
adaptors are great, the cameras are not. :-)

One could create a microscopic version with stepped (overlapping) neutral
density filters... somehow spending thousands in good optics for a microscope,
to capture the data with a £20 webcam somehow does not sound right.

Webcam images have also plenty of compression artifacts, presumably to keep up
with the transfer rate. I am not sure how one would avoid that.

Cheers

Gabriel