You can always use an EL Panel with an Arduino, load this firmware to arduino, and use the Alnitak driver

github.com/ivonnyssen/ArduinoFlatBox

Thanks Nuno. So if I understand you…. I purchase an EL Panel (www.technolight.com/product/14-inch-uv-f...-any-color-or-design) and an Arduino. Then I replace the firmware in the Arduino with the one you linked, and then EKOS will be able to control the brightness of the EL panel using the Alnitake Flip Flap driver?

Exactly

There's actually two versions of the same arduino ino (one for Revision 3 and another for Revision 4 of the Alnitak commands).

I believe that both will work with Alnitak INDI driver, but just in case, get both

github.com/ivonnyssen/ArduinoFlatBox
github.com/jwellman80/ArduinoLightbox

The notes in the Lin you sent talk about controlling a stepper motor. The EL Panel I liked to doesn't have a dimmer.
Also - it connects using a JST connector. Does that attach to an Arduino board?
Also - I don't even know how to install a new firmware in an Arduino board.

The Arduino IDE it's just like a text editor, you just have to open the ino (the firmeware file), make a change in the code if needed, choose your board, the port where it's connected and press a button. It's really that simple.

If you read the code you will find that if just want to use the brightness control, you have to replace just the line 79 line of the code...

github.com/ivonnyssen/ArduinoFlatBox/blo...r/ArduinoFlatBox.ino

You will need the dimmer if you want to set the brightness manually. If you want to adjust only using Ekos, you don't need it.

These kind of DIY projects, even a small one like the one you need, will always involve some adaptions / cuts / solder. But it's where the fun is

Ok, I’m willing to buy all the parts to this project, but I just want to make sure you understood that I need EKOS to control the brightness of the panel, and not adjust the camera exposures as most people do. I want to keep my camera exposures the same and only the light box brightness changes to get my ADU to 13000.

His does the Arduino board change the EL panel’s brightness?  There’s no dimmer controller on them.

Peter

I made a similar project with this one:
elpanelandtape.co.uk/product/13-x-13cm/

Keep in mind that it's very dificult to use the same exposure for all the filters and adjust only the pannel brightnes.
I have an Atik 383 with a shooter that needs at least 2s of exposure to hide the shadow of the shooter, so i use about 2 seconds expusure with the brightness set to 90 (in a range 0-255) for Luminance, but for HA filter, with the brightness set to maximum, i have to rise the exposure. This will hapen with a DIY Flat Pannel or with a comercial one. It will be the same.

Yes the Arduino board will manage the brightness of the EL Pannel using PWM. The board will receive the value from Ekos (or another client).

A word of advice. It's very difficult to mantain a very low value of brightness of the EL Pannel without flickering (mine starts to flickering at below of a value of 50-60). There are diferent ways to connect the EL Pannel to arduino, some more elaborated then others, but you can start with something as simple as a Mosfet.
So, if you will do flats with a C11 and a CMOS, i have no doubt that you have to use very low values of brightness, or using something to lower the brightness without dimmering the EL Pannel (some sheets of paper, for example).

How far can I have a 13" square flat panel away from the front of my C11 (with dew shield) and still get good flats?
Do I need a much larger panel?
The goal is to automate flats in a remote observatory.



 

Nuno, how do I physically connect this to an Arduino?: www.technolight.com/product/14-inch-uv-f...-any-color-or-design

What other items would I need to purchase to make such a connection?

Regarding the two versions of the Alnitak command sequence protocol (Rev 3 of 2011 and Rev 44 of 2017).

I used the later one for my first cut of Arduino code (using command strings with capital "O" rather than with zeros). Initial testing back in September (Kstars 3.5.5) brought up some issues that Jasem fixed for 3.5.7. With 3.5.7 installed further testing results prompted me to monitor the USB packets exchanged between Ekos/Indi to the Arduino controller. I discovered these commands used the older version of the protocol, the one with zeros. Looking at the indi_flipflat driver source code (flip_flat.cpp) confirmed commands issued use the zeros structure (e.g. "if (!sendCommand(">P000", response))" which results in " >P000CR" being sent to the flat panel's Arduino controller.

I investigated all the Arduino programs listed in this thread but eventually settled on a modified (by me) version of the code found on the gluonfield.com site ( gluonfield.com/spacelike/content/astrophotography-flats-panel ). Basically I went back to using the zeros and the CR an LF command terminators.

As I mentioned I used a DIY LED based solution with a few 3D printed parts (courtesy of my son) to make a panel that slips over my OTAs dew shield like a lens cap. The Arduino with a MOSFET to switch the 12V required by the LED string mount on top of the panel assembly.

Although this flat panel solution has taken months of time and trial and error it did save me some money and provided an opportunity to add to my (minimal) programming and fabrication skills. Being essentially confined to home and literally having no opportunities to take astrophotos since my last session in late October this project along with a dew heater controller has kept me somewhat sane.

Dave

Thanks Dave. As I have zero electronics skill, and have not programmed since 1984, you are in another league. If you need some extra cash, I would pay you to built a lightbox for me.

Hi Peter, that's a generous offer, but I can't commit until I know "for sure" this this is going to work. I get back home later this coming week and will actually hook all the components together and finally test in a "real world" environment. I will let you know how things work out...