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Piranha4 2K and 4K Camera Color User's Manual
03-032-20180-05
Teledyne DALSA
3. Setting Up Your Optical Configuration
Typ ically, the first thing you w ant to d o is to evalu ate the cam era’s im age qu ality u nd er op erating
cond itions sim ilar to those that you are likely to u se in you r ap p lication . In ord er to d o this, take the
follow ing step s:
The illu m ination, lens m agnification , and focu s shou ld be set u p as p er you ap p lication.
Getting the m agnification right is best accom p lished by setting the object-to-sensor d istance. Use
the form u la
lens focal length x (2 + 1/magnifi magnification)
to calcu late this d istance.
Magnification equ als the sensor p ixel size (10.56 µm ) / (you r object p ixel size in u m ).
The ap p roxim ate location of the sensor p osition is at the first gr oove in the sid e of the case, back
from the front face.
4. Camera Timing & Control
It is easiest and qu ickest to evalu ate the cam era u sing the internal tim ing setu p s for line rate and
exp osu re tim e.
Since w e recom m end starting w ith Cam era Link m ed iu m m od e, set a su itable line rate less than
40 KH z, u sing the ‘ssf’ com m and .
If this line rate is too slow for you r ap p lication, you w ill get a com p ressed im age in the scan
d irection. This shou ld not be a p roblem for a basic evalu ation .
You can set the exposure time using the ‘set’ com mand . Ensure that the exp osure time period is
not greater than the p eriod of the line rate m inu s 1.5 µsec.
The cam era w ill ind icate an error if you select an exp osu re tim e that is too long . The m inim u m
exp osu re tim e is 7 µsec.
Set you r cam era d irection u sing the ‘scd ’ com m and . Refer to the Cam era d irection d iagram in th is
m anu al for a d efinition of ‘forw ard ’ and ‘reverse’.
5. Acquiring an Image
You can now begin im aging. Unless you have an ap p lication em p loying lots of light, the im age is likely to
be too d ark.
Use the system gain to ad ju st the cam era ou tp u t to ach ieve the d esired resp onse. The system gain
range is from 1x to 10x.
Once you have a su itable resp onse, you can now focu s the lens.
If you are u sing w hite LEDs, you r im age w ill have reasonable color rep rod u ction .
The im age m ay be d arker at the ed ges d u e to lens vignetting, bu t this w ill be im p roved once the
cam era is calibrated .
Calibration is p erform ed u sing a w hite reference w here you r object is norm ally located .
o
Use a w hite m aterial that has no textu re, su ch as a non glossy p lastic.
