Dalsa Piranha 3 P3-80-08k40-00-R, Руководство пользователя

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Piranha 3 User Manual
03-032-10216-06 Teledyne DALSA
36
Flat Field Correction Restrictions
It is im p ortant to d o the FPN correction first. Resu lts of the FPN correction are u sed in the
PRN U p roced u re. We recom m end that you rep eat the correction w hen a tem p eratu re
change greater than 10°C occu rs or if you change the analog gain, integration tim e, or line
rate.
PRN U correction requ ires a clean, w hite reference. The qu ality of this reference is
im p ortant for p rop er calibration. White p ap er is often not su fficient becau se the grain in
the w hite p ap er w ill d istort the correction. White p lastic or w hite ceram ic w ill lead to
better balancing.
For best resu lts, ensu re that:

50 or 60 H z am bient light flicker is su fficiently low not to affect cam era p erform ance
and calibration resu lts.

For best resu lts, the analog gain shou ld be ad ju sted for the exp ected op erating
cond itions and the ratio of the brightest to d arkest p ixel in a tap shou ld be less than 3
to 1 w here:

The cam era is cap able of op erating u nd er a range of 8 to 1, bu t w ill clip valu es larger
than this ratio.

The brightest p ixel shou ld be slightly below the target ou tp u t.

When 6.25% of p ixels from a single row w ithin the region of interest are clip p ed , flat
field correction resu lts m ay be inaccu rate.

Correction resu lts are valid only for the cu rrent analog gain and offset valu es . If you
change these valu es, it is recom m end ed that you recalcu late you r coefficients.
Brightest Pixel (per tap)
Darkest Pixel (per tap)
Note: If your
illumination or white
reference does not
extend the full field of
view of the camera,
the camera will send a
warning.
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