Lumenera Lt-C1610, User Manual

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Teledyne Lumenera Lt Series Feature Reference • 73
Display Name Feature & Values Description Device
Version
& View
Auto Iris irisAuto Iris automatic mode
1.00
DFNC
Beginner
Off Off
Continuous Continuous
Reinitialize Iris irisInit Initializes the iris
1.00
DFNC
Beginner
F-Stop auto min irisAutoMin The user set limit to the lowest iris F-Stop
number (i.e. the maximum iris aperture opening
– maximum exposure) when Auto Iris is enabled.
The maximum iris F-Stop number (minimum
aperture) is lens dependent.
1.00
DFNC
Expert
P-Iris step count irisStepsCount
Number of positions in the P-Iris stepping motor.
Users must consult their lens's manual and set it
correctly before accessing their lens.
1.00
DFNC
Guru
5.6.2 F-stops vs. Exposure Overview
The Lt Series Lens F-stop control allows adjusting the lens iris with small incremental steps. It is
important to remember that full stop increases will half the incoming illumination and requires
doubling the exposure time to compensate.
The common aperture scale is as follows:
f/1.4 (large opening of aperture – a lot of light)
f/2.0 (half as much light as f/1.4)
f/2.8 (half as much light as f/2.0)
f/4.0 (half again)
f/5.6 (half again)
f/8.0 (half again)
f/11.0 (half again)
f/16.0 (half again)
f/22.0 (half again)
f/32.0 (very small aperture, lets in little light)
For users unfamiliar with lens iris controls (F-stops), the following photography site has a good
explanation of this subject and along with a handy table of standard F-stop values.
Digital Camera World’s web site
https://www.digitalcameraworld.com/tutorials/cheat-sheet-how-to-understand-f-stops