Focus adjustment 393

Description

internal use

used on big the Xeon PC - 192.168.0.6
restore from /home/elphel/test_focusing/default.conf-xml
quick get&show
find grid (if error - increase/decrease exposure using the 'camera settings' button - the range is 2.5-5.0 ms - rerun steps 3. and 4.)
no-move measure
show PSF
adjust screws
repeat from 4. until good

Assembled SFE without lens and without IR-cut filter (can be with the filter if the target lens is different)
M12 adapter
2 spacers: 5mm and 4.7mm (shaved off 0.3mm (made from 5mm spacer) for optimal adjustment)
Lens N125B04530W with IR-cut filter. If the target lens is different, still use this one for adjustment then replace. Wrap the thread of the lens with the teflon tape for better thread fitting - 2 layers is enough. When screwing in make sure the tape does not get in the optical path. Screw in the lens until full stop.

Fig.2a SFE parts

Fig.2b Sensor teflon spacers

Focus adjustment screws - do not overtighten initially. Later, right before starting the procedure when the camera is against the pattern - turn it on, while in jpeg open the control interface and adjust the screws for the best manual focus (do not apply too much force).

Fig.3 Focus adjustment screws

Take a longer cable - at least 100mm
Connect to port 0
Set the camera address to 192.168.0.38
Make sure the power supply provides the right voltage - 12V or 48V. If possible install PoE compatible power board - 10386.

Fig.4 Assembled focusing setup

Use the wallpaper pattern.
Notice the distance from pattern.
Notice the height of the camera. Try to position the camera to point to the center of imaginary rectangle where laser pointers mark the corners. Actually the center is marked with a blue masking tape triangle.

Fig.5 Tripod placement

Fig.6 Tripod closeup

Make sure all 4 lasers are pointing in the right spots - "manual laser pointers" yellow button in the imagej plugin

Fig.7 Laser spot markings