@resam thank you! and sorry for my late reply. i'm testing it right now.
it looks, like it works. somehow... i was able to download a single jpg file during the print, which has a size of 2gb 
but i could not open it.
edit: ...achtion=snapshot instead of ...action=stream would help, i guess 
Can you make a small guide, how to set this up on an sbc?
After cloning from github i don't know what to do... 
I'm using another SBC with octoprint, webcam and octolapse. But the connection to the duet ethernet is not fast enough sometimes.
I would love to make timelapses with my deltaprinter.
Thank you for all your work 
After a while i found a bit of time to work on my delta again.
Thought about setting the duet up completely from zero.
Is it possible that i have to put a "S2" after the G32 to get an effect?
I tried now to print some small surfaces, just where to probe touches the glass.
Then i adjusted the H values in bed.g. Now it looks a bit better, everytime i do this.
The deviation is still a bit high, i think:
Calibrated 3 factors using 7 points, deviation before 0.249 after 0.131
Is it possible to do a double touch with the sensor?
Thank you for your time
Thank you. I will try more calibration points or factors next time.
My idea was, to calibrate not to many factors every time. Just the ones, which could change between the prints.
Delta radius, tower angular position and diagonal rod length should always stay the same, once they are calibratet. Or am i wrong?
Sorry for my late answer.
The deviation is zero after calibration:
Calibrated 4 factors using 4 points, deviation before 4.954 after 0.000
When i tried to print, the nozzle is to high/low always at the same areas.
Even when i changed an H-parameter to 0.8.
One thing is a bit strange. When i try to print, the intro line is always a bit higher than the rest of the first layer. I had this behaviour already with ramps.
Edit:
It looks, like this guy has the same problems as i:
https://forum.duet3d.com/topic/5175/duet-level-bed-and-g29-32
Edit2:
Inbetween i changed every of the three H-parameter between 0.5 and 1.5 milimeter and printed some small 10x10mm surfaces as close to the probe point as possible.
There is no visible difference between the prints.
Deviation is always more or less the same before and zero after calibration.
I think there is something in the firmware, that overrides the results.
which sys-files could i delete? are there some values which could be safed accidently to the eeprom?
I changed to 3 factor calibration but there was no visible difference.
Hello
Same problem here. 
I try to calibrate my delta since a few days now.
Switched from Ramps 1.4 to duet ethernet and from 12 to 24 Volt 
Here are my config files:
; bed.g
; called to perform automatic delta calibration via G32
;
; generated by RepRapFirmware Configuration Tool on Sat Apr 21 2018 17:49:51 GMT+0200 (Mitteleuropäische Sommerzeit)
M561 ; clear any bed transform
G28 ; home all towers
;M98 Pdeployprobe.g ; deploy mechanical Z probe
; Probe the bed at 3 peripheral and 0 halfway points, and perform 3-factor auto compensation
; Before running this, you should have set up your Z-probe trigger height to suit your build, in the G31 command in config.g.
G30 P0 X-32 Y132 H0.48 Z-99999 ;war ...
G30 P1 X68 Y-41 H0.13 Z-99999 ;war 0.03
G30 P2 X-117 Y-41 H0.07 Z-99999 ;war 0.07
G30 P3 X-32 Y17 H0 Z-99999 S4
; Use S-1 for measurements only, without calculations. Use S4 for endstop heights and Z-height only. Use S6 for full 6 factors
; If your Z probe has significantly different trigger heights depending on XY position, adjust the H parameters in the G30 commands accordingly. The value of each H parameter should be (trigger height at that XY position) - (trigger height at centre of bed)
;M98 Pretractprobe.g ; retract mechanical Z probe
; Configuration file for Duet Ethernet (firmware version 1.20 or newer)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool on Sat Apr 21 2018 17:49:51 GMT+0200 (Mitteleuropäische Sommerzeit)
; General preferences
G90 ; Send absolute coordinates...
M83 ; ...but relative extruder moves
M665 R265.11 L410.79 B116 H492.17 ; Set delta radius, diagonal rod length, printable radius and homed height
M666 X-3.98 Y0 Z-3.8 ; Put your endstop adjustments here, or let auto calibration find them
; Network
M550 PDelta RR Duet ; Set machine name
M540 PBE:xx:DE:xx:FE:xx ; Set MAC address
M552 P192.168.xxx.xxx S1 ; Enable network and set IP address
M553 P255.255.255.0 ; Set netmask
M554 P192.168.xxx.xxx ; Set gateway
M586 P0 S1 ; Enable HTTP
M586 P1 S1 ; Enable FTP
M586 P2 S1 ; Enable Telnet
; Drives
M569 P0 S0 ; Drive 0 goes backwards
M569 P1 S0 ; Drive 1 goes backwards
M569 P2 S0 ; Drive 2 goes backwards
M569 P3 S1 ; Drive 3 goes forwards
M350 X16 Y16 Z16 E16 I1 ; Configure microstepping with interpolation
M92 X200 Y200 Z200 E107 ; Set steps per mm
M566 X1800 Y1800 Z1800 E1200 ; Set maximum instantaneous speed changes (mm/min)
M203 X18000 Y18000 Z18000 E1200 ; Set maximum speeds (mm/min)
M201 X2000 Y2000 Z2000 E1000 ; Set accelerations (mm/s^2)
M906 X1300 Y1300 Z1300 E1400 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout
; Axis Limits
M208 Z-0.5 S1 ; Set minimum Z
; Endstops
M574 X2 Y2 Z2 S3 ; Set endstops controlled by motor load detection
; Z-Probe
M307 H3 A-1 C-1 D-1
M558 P9 X0 Y0 Z1 H10 F500 T2000 ; Set Z probe type and the dive height + speeds
G31 P25 Z0.76 ; Set Z probe trigger value, offset (X32 Y-17) and trigger height
M557 R100 S20 ; Define mesh grid
; Heaters
M305 P0 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 0
M143 H0 S120 ; Set temperature limit for heater 0 to 120C
M305 P1 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 1
M143 H1 S280 ; Set temperature limit for heater 1 to 280C
; Fans
M106 P0 S1 I0 F500 H1 T45 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned on
M106 P1 S0 I0 F4.7 H-1 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned off
M106 P2 S0 I0 F4.7 H-1 ; Set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned off
; Tools
M563 P0 D0 H1 ; Define tool 0
G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
G10 P0 R0 S0 ; Set initial tool 0 active and standby temperatures to 0C
; Motor stall detection
;M915 X Y Z S10 F1 R1
; Automatic saving after power loss is not enabled
; Custom settings are not configured
Firmware is 1.21
No Display, just webinterface.
Following system files are present:
bed.g
cancel.g
config.g
config.g.bak
config.json
deployprobe.g
homedelta.g
iap.bin
iap4e.bin
pause.g
resume.g
resurrect.g
retractprobe.g
sleep.g
tfree0.g
tpost0.g
tpre0.g
I calculated the probe positions, to match the coordinates in a macro, to check, if the calibration has an effect.
it looks like the "H correction" makes no difference. No matter what i do.
Because i use a glass surface, i think it should be flat.
So endstop correction or tilt correction should be enough to meassure before i start a print.
Thank you for your time