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by pootle
Wed May 27, 2020 8:28 am
Forum: Camera board
Topic: setting analog / digital gain in (python) picamera
Replies: 1
Views: 63

setting analog / digital gain in (python) picamera

I see in the HQ camera thread that raspistill allows analog gain to be set directly using -ag.

But with a picamera.PiCamera object the analog_gain attribute cannot be written.

Is there a way to set analog gain (and digital gain) via python / picamera - typically for when exposure mode is off.
by pootle
Thu May 21, 2020 4:40 pm
Forum: General discussion
Topic: Raspberry Pi 4 USB mass storage beta (beta means it not ready yet, and not officially released!)
Replies: 282
Views: 56844

Re: Raspberry Pi 4 USB mass storage beta

Just done this with an original pi4 and a crucial bx500 240GB SSD connected with a cheap amazon usb - sata cable.

Just a logitech K400+ wireless kbd connected

Worked perfectly.
by pootle
Sun May 17, 2020 8:03 am
Forum: Python
Topic: Enhancing picamera with new MMAL features
Replies: 1
Views: 150

Re: Enhancing picamera with new MMAL features

OOh! that's really useful. I've just made a stepper motor based focuser for a canon lens, driven from my pi and I have a python app that drives the camera, auto focus is the next step....
by pootle
Tue May 12, 2020 9:43 pm
Forum: Camera board
Topic: Raspberry Pi High Quality Camera
Replies: 149
Views: 8965

Re: Raspberry Pi High Quality Camera

Maybe it is better to use a macro-style focusing rail setup, even at these long distances (8 m in my case). That's a good idea, focusing is pretty difficult, and I tried with a 400m F5.6 prime I have, but gave up because I couldn't reliably get it sharp. It's that or making a little motor driven fo...
by pootle
Tue May 12, 2020 10:05 am
Forum: Camera board
Topic: Raspberry Pi High Quality Camera
Replies: 149
Views: 8965

Re: Raspberry Pi High Quality Camera with ludicous lens

I tried my HQ camera in a pikon, but was somewhat disappointed, so I printed a canon adapter for the camera and tried it with a Canon 70-200 F2.8 L. It is pretty spectacular. The test card I printed on a laser printer A4 sheet (and the source image was a bit flakey), and it is 4m from the camera wit...
by pootle
Thu May 07, 2020 2:37 pm
Forum: Camera board
Topic: HQ camera mechnical info - sensor distance?
Replies: 3
Views: 150

Re: HQ camera mechnical info - sensor distance?

Mine was very stiff initially, so the part about the distance appearing too short is fixed by adjusting it, but it's the distance between board and sensor I'm after - when you're not using the threaded mount, but mounting the board by the 4 corner holes.
by pootle
Thu May 07, 2020 1:14 pm
Forum: Camera board
Topic: HQ camera mechnical info - sensor distance?
Replies: 3
Views: 150

HQ camera mechnical info - sensor distance?

It would be really useful if the mechanical drawing included the distance from board surface to sensor surface. I am slightly confused (unfortunately common these days) as the info here says the flange to sensor distance for a cs mount is 12.526mm, but I measure the flange to board surface distance ...
by pootle
Tue May 05, 2020 5:40 am
Forum: Camera board
Topic: focus with long lens on HQ camera board...
Replies: 4
Views: 277

solved: focus with long lens on HQ camera board...

Ah! the blinding light! Hadn't realised that adapter had the same thread both ends! That's just fine and dandy now. Works a treat.

Thanks 6by9
by pootle
Mon May 04, 2020 2:52 pm
Forum: Camera board
Topic: focus with long lens on HQ camera board...
Replies: 4
Views: 277

focus with long lens on HQ camera board...

To get focus on infinity with the long lens and the near - far adjuster about 1/4 in from far, I have the adapter in the camera board as far out as it will go (only 1 1/2 turns from falling out) and still I have to have the lens.only about 1 turn from falling out of the adapter. I can screw both in ...
by pootle
Wed Apr 22, 2020 12:41 pm
Forum: General discussion
Topic: ifconfig inside crontab fails on raspbian lite
Replies: 2
Views: 78

Re: ifconfig inside crontab fails on raspbian lite

Ah! thanks for lifting the brainfog. I use shell so rarely it's easy to make silly mistakes.
by pootle
Wed Apr 22, 2020 12:18 pm
Forum: General discussion
Topic: ifconfig inside crontab fails on raspbian lite
Replies: 2
Views: 78

ifconfig inside crontab fails on raspbian lite

I have put the following in crontab: @reboot sleep 55; /sbin/ifconfig >>/home/pi/test.log 2> &1 but it disappears without trace - not even an empty file. I'm on a pi 0 W running raspbian lite Have I done something silly or is there a real problem here? I was calling it using subprocess from python, ...
by pootle
Wed Jan 15, 2020 11:02 am
Forum: General discussion
Topic: Control board for a central heating style pump with dutycycle control
Replies: 11
Views: 592

Re: Control board for a central heating style pump with dutycycle control

Is that full variable speed, or a number of set speeds? IIRC the Grundfos pump on my heating system just has three speed settings, probably using different combinations of coils on the motor so not something that can be controlled externally. The pump does have 3 preset speeds, but the controller a...
by pootle
Wed Jan 15, 2020 8:36 am
Forum: Python
Topic: HELP WITH Two stepper motors at same time
Replies: 3
Views: 322

Re: HELP WITH Two stepper motors at same time

it's hard to follow your code when all the indentation is lost, You're starting in the right place with threading though. Can you post the code with indentation present.....?
by pootle
Wed Jan 15, 2020 8:31 am
Forum: General discussion
Topic: Control board for a central heating style pump with dutycycle control
Replies: 11
Views: 592

Re: Control board for a central heating style pump with dutycycle control

Most motors don't work with electronic dimmers, as "speed control" devices, so no "duty-cycle control" other than a few seconds on/off is possible. I'm specifically interested in central heating pump type motors (Grundfos etc), Don't care about most motors. I have a control unit on 1 that does cont...
by pootle
Mon Jan 13, 2020 12:08 pm
Forum: General discussion
Topic: Control board for a central heating style pump with dutycycle control
Replies: 11
Views: 592

Control board for a central heating style pump with dutycycle control

I want to control a standard mains central heating type pump from a Raspberry pi, with some basic control of speed. Presumably something with opto isolator in it, or driven with an rf signal Most of the stuff I've found uses relays (really? relays still?) like this one , which would clearly not work...
by pootle
Sun Jan 05, 2020 1:28 pm
Forum: General discussion
Topic: pi4, picamera 64 bit os and darknet - yolov3 is it possible?
Replies: 0
Views: 284

pi4, picamera 64 bit os and darknet - yolov3 is it possible?

Any way to get raspberry pi camera running on ubuntu server 64 on a raspberry pi? I've setup ubuntu server 64bit on a pi4, and starting from the info jbeale (and others) put in this thread , I have darknet - nnpack running well using both the tiny and standard models. In a separate universe I setup ...
by pootle
Sat Jan 04, 2020 2:00 pm
Forum: General discussion
Topic: Image recognition - what 4GB of memory can do
Replies: 57
Views: 6040

Re: Image recognition - what 4GB of memory can do

OOh! need to get the pi camera working too.....
by pootle
Sat Jan 04, 2020 1:59 pm
Forum: General discussion
Topic: Image recognition - what 4GB of memory can do
Replies: 57
Views: 6040

Re: Image recognition - what 4GB of memory can do

Cracking info, have built this on ubuntu 64 bit for pi and installed both standard and tiny, both working. Small mammal recognition seems to be a bit dodgy though! Just about to try streaming multiple images through it, rather than 1 shoting it.
20200102_125843pred.jpg
20200102_125843pred.jpg (236.34 KiB) Viewed 255 times
by pootle
Sat Jan 04, 2020 8:18 am
Forum: Automation, sensing and robotics
Topic: Stepper motor RPM using A4988 and pi 4
Replies: 2
Views: 310

Re: Stepper motor RPM using A4988 and pi 4

Why not try the code posted in response to your earlier question?
by pootle
Fri Jan 03, 2020 9:19 am
Forum: Python
Topic: td6600 driver and nema 17 stepper RPM
Replies: 2
Views: 311

Re: td6600 driver and nema 17 stepper RPM

A td6600 controller is not a good choice for a pi as you will need to level convert the control signals, much better to use (for a basic stepper controller like this) one of the A4988 family which use the same logic levels as the pi, so can be driven directly from gpio pins. Also these controllers a...
by pootle
Wed Jan 01, 2020 10:04 am
Forum: Python
Topic: Stepper motor RPM
Replies: 2
Views: 273

Re: Stepper motor RPM

This adafruit hat is not very good at driving steppers, I tested it in some detail, the info is here , but in summary (assuming their base code is still as it was then). standard adafruit library maxes out at around 80 steps per second. If your motor is 1.8 degrees per step this is about 25 rpm with...
by pootle
Fri Dec 20, 2019 9:39 am
Forum: Python
Topic: How to speed up measurement up to 100 value per second in spi interface,
Replies: 1
Views: 167

Re: How to speed up measurement up to 100 value per second in spi interface,

Can you clock the board to run faster?
Is the code optimized to make best use of the available spi bandwidth?
What is the current utilisation level of the spi bus?
What is the current measurement rate you can get?

Provide lots more information and we may be able to help better.
by pootle
Wed Oct 30, 2019 9:21 am
Forum: General discussion
Topic: How to install docker on raspberrypi effectively
Replies: 1
Views: 520

Re: How to install docker on raspberrypi effectively

Much easier to use something like this - especially if you want nodered and similar stuff.

or this if you want straight docker. ( I did have to reboot after install before it all worked on this one.)
by pootle
Tue Oct 22, 2019 10:13 am
Forum: General discussion
Topic: Pi Wifi IP messed up
Replies: 8
Views: 601

Re: Pi Wifi IP messed up

post the output from ifconfig.....
by pootle
Fri Oct 18, 2019 7:25 am
Forum: Automation, sensing and robotics
Topic: Open API Light Fixtures
Replies: 1
Views: 1012

Re: Open API Light Fixtures

Not directly open API, but phillips hue (expensive) and Ikea TRÅDFRI (much cheaper) although closed systems are based on zigbee and this video describes a way to get at them directly.

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