View Full Version : Fine exposure control

February 15, 2013, 10:46:41
Using the DFK 72AUC02-F

I can use the parameter interface to adjust this value. The interface reports a minrange=-13, maxrange=-2 and delta=1. This gives me 12 possible values but in practise this adjustment feels rather course. I'm not sure what these values represent but they do not map 1:1 to shutter speeds ...

I have noticed that adjusting the Exposure slider in the standard icImagingControl1.ShowPropertyDialog, I appear to have much finer control of the exposure. For example the exposures 1/2000, 1/1667, 1/1429, 1/1250 and 1/1111 all give a value of -10 when I read the parameter back after changing exposure in the dialog.

How do I achieve similar fine control of exposure as the dialog slider.


Stefan Geissler
February 15, 2013, 16:19:01
Hi Jerry,

please look at http://www.imagingcontrol.com/en_US/support/documentation/dotnet/tech_VCDProperties.htm

February 15, 2013, 17:04:29
Thanks, just what I needed.

March 5, 2013, 17:53:16

I've been trying to map exposure to a slider position. Since the mapping is logarithmic (according to AbsDimFunction) is there a simple way to map between slider position and exposure value. Range is from 0 to 30.

Is there some sample code for this somewhere.


Stefan Geissler
March 6, 2013, 09:18:01
Hi JErry,

the simple way is using an 30 elements array, that contains the exposure times of interest. The slider is used to set the index in the array.

The distribution of the exposure times can be hardcoded in your source code.

March 6, 2013, 16:04:30
Ok. I can do it like that.

I have another question regarding frame rates. I use a mode that has an advertised rate of 18.65 fps. However I never see that much, usually only around 14 fps. The CPU is only loaded to < 5%. The same applies if go to a much faster rate with 4x binning. Max is supposed to be 51 fps but I only ever achieve 23 fps with minimal CPU load again (< 5%). Can you explain this ?

Stefan Geissler
March 7, 2013, 11:03:05
Hi Jerry,

The calculation of possible frame rates in binning modus is at least somewhat "vague" in the 72 series. Therefore, you receive different frame rates. I am very sorry for this.