Giving devices access to your private Git Repositories using SSH

/

A little while back I wrote a blog post telling folks (and future me) how to set up secure sockets so that you can log into remote devices without passwords and create Visual Studio Code remote sessions. Here’s the follow-up, which tells you how to use your SSL keys to give a device access to your private GitHub repositories.

I like to keep my repositories private until I’ve got them kind of sorted. This makes it tricky if I’m deploying to a newly set up remote Raspberry Pi, since it needs GitHub credentials to access private stuff. The best way to solve this problem is to put a copy of the device SSL key onto your GitHub account. It’s easy to do and works a treat. Start by going to GitHub and opening your personal Settings (the one at the top right, not the settings for a particular repository). Then click SSH and GPG keys.

You can see my keys here. Now click New SSH Key. A dialogue will appear asking for two things: the name for the key and the key itself. I use the machine name as the name. You can find the key in the file id_ed25519.pub in the local .ssh folder of your new machine. This file was created when you did ssh-keygen to set up ssh on the machine. Enter the info and close the dialogue. Once you’ve done this you can use the ssh form of git clone to grab private repositories from GitHub.

git clone git@github.com:CrazyRobMiles/custard-cream-camera.git

You’ll need to put your GitHub username and your repository name into the above command. Note that the https way of referring to repositories won’t work.

GitHub will send you an email to tell you when you’ve set one of these up. It also lets you track the last time the key was used. You can remove keys that you are not using.

Nothing informs the writing process like writing

/

I took this with the custard Cream Camera over at Ross’s place. I added the colours later.

I’m putting together an article about the custard cream camera and I’m grappling with how I’m going to structure it, and what I’m going to have space to talk about. I’ve had this problem lots of times, and I’ve discovered that the best way to structure an article is to start writing stuff that you think might make sense. After I’ve written a bit, walked away from it, come back to it and read it a few times a structure emerges that works. Trying to build the thing in my head just doesn’t work. I have to have something to play with first.

This might mean that I throw away quite a bit of the stuff that I wrote, but I never actually discard any of it. Instead, everything I throw away is stored in a “scrap” folder so that I can go back to it later, perhaps for another article or a blog post. In fact, I only really consider myself to be making progress on something when I have a few pages in the scrap folder…

Toll Memories

/

The Control Centre back in the day

One of my (few) claims to fame is that I wrote some of the software that used to manage toll collection on the Humber Bridge. Ian wrote the control room software, Siemens programmed the toll booths and I wrote the management interface.

This is my bit

It was great fun. It ran for quite a few years and only failed once, when someone testing the uninterruptable power supply sent a DC spike to all the devices and blew up the power supplies for the network routers. I had to go in and move some wires around to get it going again.

The rest of the time it just worked, registering tolls, indicating when the number of axles detected on a vehicle didn’t match the class the booth operator had entered and producing summary data. We closed it down a few years ago.

I was reminded of this when I paid for some crossings today. I had to download and use an app, of course. You can pay for you crossings in advance, which is nice, but you don’t know whether the crossings you paid for have registered properly until two days after the crossing, which is one day after the deadline for paying for the crossing. Which seems a bit odd to me. I’ll just have to hope that the people who built the new system are as good at their jobs as Ian and I were all those years ago.

Soldering and Solar Eclipse at the Hardware Meetup

/

This was taken during the eclipse. You can see the shape of the sun in the lens flare at the bottom of the image

We had a great time soldering at the Hardware Meetup, then we headed out to the middle of Hull to take in the solar eclipse that I’d arranged for the evening’s entertainment. It was awesome. We went past Queen’s Gardens and there were lots of folks just taking in the site. Some had set up eclipse picnics on the grass. I’d made a little pinhole viewer which worked as long as you had a small head. It was a great evening.

These shots have not been tampered with. It’s just how the light bounced around the lens

We’ll be doing this again in two weeks. Minus the eclipse.

Update

Ian was with us for the evening and had brought along a camera equipped with a telephoto lens and a “Big Stopper” 15 stop filter. The filter reduced the light of the sun to a level that could be photographed. He took some really nice shots:

Coming (or going)

Going (or coming)

Eclipse of the Maritime museum

Caira Camera

/

The Yellow thing on the back is my iphone

I’ve been after a Caira camera from Camera Intelligence for a while. And last week I managed to get one for a knock down price. You might have heard of Caira in its first incarnation as the “Alice” camera. Caira is the next step towards a fully fledged product. It brings all the built-in AI smarts of the original plus voice controlled editing via Google Nanobanana.

The camera itself is a well hewn lump of aluminium which contains a beefy processor alongside an AI accelerator. It has two buttons. One turns it on and the other takes a picture. All other controls are provided by an iPhone app (no support for Android at the moment) which gives you a fairly conventional looking camera interface.

The camera creates a Wi-Fi connection to your phone which is set up each time the app starts. This extra step, and the fact that the camera takes quite a while to get going from cold, means that whipping the camera out and grabbing a snap is not an option. But the camera does have sleep modes from which it wakes up pretty quickly. The camera is powered by a built-in battery you charge over USB-C. The battery is not user replaceable, but I would hope that at some point it will be possible to get it replaced. I’ve not used it long enough to get a much of an idea of possible battery life, but it seems OK.

You can stick your iPhone to the back of the camera using a mag-safe connection. This is pretty sturdy, particularly if you have a mag-safe case on the phone. However, you don’t need to do this. You can use your phone as a remote viewfinder (although this makes holding everything tricky). Pictures taken on with the camera are automatically transferred to the phone as well as being stored in the 64Gb memory inside the camera. Video is stored in the camera and then transferred to the phone later. The pictures look really good. The camera has a micro four-thirds sensor and lens mount. I used a lens from my original Olympus Pen EP1.

The sensor is physically much larger than ones you find in phones and lets you add proper depth to your photos. It’s only 12 Megapixels resolution, but for social messages and small prints this will work fine. The lens I’m using is far from the best, but I’m really pleased with how the images look. Apparently the exposure and colour balance are tweaked by AI algorithms to give consistency across different lenses and conditions. I’m not sure about that, but the shots look pretty fine to me. The camera will capture raw images in DNG format, the one above was taken as a jpeg.

The camera has a whole bunch of different image effects that all look rather nice. In addition you can use natural language via spoken input to tell the camera what to do. The voice commands include picture adjustments, taking shots and selecting styles. This all happens on the device, without any need for a network connection.

If you are prepared to stump up 7 pounds a month after the first six months of camera ownership you can also use Google Nanobanana to perform image processing. This seems to work in exactly the same way as for the Custard Cream Camera (probably using the same API). You give your command, the command goes up to the cloud and then a while later an updated image returns. There are lots of guardrails in place to stop malicious or unpleasant edits, but you can still have fun. The camera was quite happy to add some dragons to one picture that I took. You can’t process an infinite number of images though, I started with 50 tokens which has now been whittled down a bit. Rather annoyingly the “cost” of each image is not the same, nor is it one credit. I’ve no idea how your tokens get replenished and the documentation is not very forthcoming on this.

Physically using the camera is a lot trickier than it should be. The construction feels super sturdy, there is a grip shape on the right of the camera, but if you use this it puts your fingers in the right place to hit all the wrong buttons if you try to grip the camera. The auto focus is a lot slower than I’m used to, although it does get there eventually. It’s not very easy to see when you get focus though. The focus area turns green, but this didn’t seem very obvious to me. I just wait for the lens to stop rattling. One thing that does work really well is the manual focus. You can use the focus ring on the lens and the camera can display a really useful black and white zoom of the focus area.

It’s not very obvious when you’ve taken a picture. A new thumbnail appears on the bottom right of the screen, but for me this is covered by my hand. A shutter sound would be a lovely addition, although I’ve discovered that the phone does vibrate when a picture is taken. It’s not clear how you get pictures out of the camera storage. I was hoping the camera would pop up as a storage device when I plugged it into my PC, but this did not happen. The support and documentation is not great either. The answers to simple questions like “How do I turn the camera off” are hidden in the Troubleshooting section. And the FAQ page is empty.

This is a properly interesting device which is just at the start of its trajectory. The voice command stuff is useful and the Nanobana image transformation removes the need for complex image processing. You can just say “remove the people from this scene and make it night time” and it will do something which will probably be quite impressive. There’s nothing particularly wrong here which can’t be fixed by ongoing development, and a ton of potential for a really compelling device. If you like being at the cutting edge of something, and are prepared for that, this camera might be of interest; particularly if you’ve only ever taken pictures with your phone and want to try getting the most out of more sophisticated lens arrangement. If you do decide to take the plunge, make sure that you have a micro four thirds lens to put on the camera. They do a nice deal on a lens you can buy at the same time as the camera. I’m going to keep playing with Ciara and I look forward to seeing what I can make with it.

Driffield Steam Fair

/

Driffield Steam Fair was awesome this year. Amazing weather (no surprises there) but also the hugest (It’s a word) range of engines of different shapes and sizes. In honour of the occasion I lugged around my very heavy and very old Hasselblad with the super heavy telephoto lens and took a bunch of shots. I’m not unhappy with the results.

If you are wondering why the pictures also include a moped, it’s because I used to have one rather like it.

Hammer Horror

/

I thought I’d add some lights and whatnot to my printer server. This means adding header pins to my Pi. I thought I’d use the hammer headers from Pimoroni rather than do soldering. I bought a bunch a while back because they were reduced. They are reduced at the moment too.

The idea is simple enough. Pop the Pi on the jig, insert the headers, pop the cover thing on and then bash it with a hammer until the pins are in. Except that I got a bit too keen and bashed the pins all the way through the board (don’t do this). “Never mind”, I thought. “I’ll just pull the pins back a bit and all will be well”. It wasn’t. I then spent an entire morning trying to work out why my pixels weren’t lighting up before discovering that if the pins go all the way through the board they don’t make proper contact. If you have a go with these make sure that you arrange things so that the pins don’t go very far out of the other side of the Pi.

I got the board to work by soldering all the pins into place. And on the journey to this I discovered lots of fun things about controlling neopixels from Python on a Pi. Pro tip: your code has to run in supervisor mode. It really made me want to go back to using a PICO where it all just works.

Anyhoo, I’ve got my leds working now, which is nice.

Printer fun

/

I’m writing an article about using a Raspberry Pi as a printer server. I’m using the cheapest Raspberry Pi, the Pi Zero W. It’s a great way of making cheap colour printing available to your household. Above is a picture of a printer printing a picture of a printer printing a picture of a printer. The thing on the right is the Pi powered print server. Two green lights is a good thing.

Generative AI and the future of creativity

/

By making the Custard Cream Camera I may have stepped on a hornet’s nest of debate about generative AI and the future of creativity. A lot of photographers and artists are very worried about the impact of generative AI on the creative process. I feel their pain. As a writer I know that AI models trained on my words are now writing like Rob Miles. There might even be some photographic models trained on what I’ve posted on Flickr over the years. In which case, good luck to them….

Anyhoo, we can now do things with our pictures that would previously have been time confusing or impossible. I made the picture above by taking a picture with the Custard Cream Camera and asking it to make it look like a comic book illustration. To my untrained eyes it looks OK. To a proper illustrator it probably looks terrible, but I can live with that. I’ve been having a lot of fun taking pictures and then asking the nano banana generative AI photographic thingy fiddle with them.

I understand that the service has guard rails to ensure it won’t do anything “bad” and I have a policy of never posting identifiable pictures of anyone but me unless I have the explicit permission of the person in question, so I don’t think I’m putting anyone at risk here. But we do need to be mindful that we are now entering a time when it is much, much, easier to fiddle with media or even create brand new stuff.

Of course, this has happened before. When photography came along I’m sure that lots of artists were very upset that there was now a much easier and cheaper way of making pictures. And when word processors with grammar and spelling chequers arrived there was much muttering about how this was making things too easy. And don’t get me started about the replacement of log tables by calculators.

You might argue that we really should put this genie back in its bottle, that this form of human replacement is going to do away with creativity as we know it and usher in a world where everything is made by machines driven by what they have already seen. And so nobody should use generative AI for anything. I’m sure a similar argument was put forward when photography was getting started.

I kind of feel the reverse. I think we should fiddle with this technology as much as we can. And we will discover limitations. We’ll learn how to spot what was made by AI, we’ll lament the lack of the human touch in generated works. And we’ll find we prefer things made by people. Creatives will find ways to use this stuff that we just don’t know about yet and the world will move on, richer and more interesting. And I’m going to keep taking analogue pictures on film as well as playing with the Custard Cream Camera.

Ditch your passwords with Secure Sockets

/

Secure Sockets are super useful. And it is worth knowing how to set them up for use on a Raspberry Pi. I’m just documenting these things here so that I can refer back to this post whenever I need to remember what to do.

The situation is this: You’ve just set up a new Raspberry Pi using the wonderful Raspberry Pi Imager software. You’ve set the machine name, enabled SSL and configured the WiFi so that the Pi will wake up and connect to your network. Next you need to make it easy to connect to. Let’s start with the first part, creating an SSL identity on your new Pi.

You perform this first step on your Pi. You’re going to make a folder to hold keys and a unique key that will identify this device. The first thing you do is connect from the console on your computer (in my case a Windows PC) to your new Pi. If you’ve set the Pi up to use SSL and Password authentication (which is what I do) then you open a command prompt on your PC and type:

ssh printserver.local -l rob

The ssh command above has two arguments. The first is the network address of the machine on the local network. This is the machine name followed by “.local”. I’ve just made a new machine called printserver, so I’m going for printerserver.local. The second argument (after the -l - which is lower case L by the way) is the username that you created on the Pi. If you leave this out the ssh call will use the username from the machine you are using to connect. If you call yourself the same name on everything this will work, but it didn’t for me. I created the pi with the username “rob” because I am an egomaniac. Your name might be different.

After you have entered this command you will be asked to confirm that you want to add this machine in your local key store on your PC. You do, so say yes. Next you will be asked for the password for the user on the Pi (in my case the password for rob) and then you will be logged in as a terminal user on the machine.

Now you want to give your new machine a unique identity in the world and set up a key storage location. Issue the command below:

ssh-keygen

You will be asked a series of questions. Just press return after each of them. Now you have a key storage on your device, along with an SSH key for that device. Now you switch back to the terminal on your PC. What you are going to do now is copy the key from your PC onto your new Pi. This is good because it means you’ll be able to open an SSL ternal session without entering a password. It’s also good because any programs that want to use SSL (for example Visual Studio Code remote terminal) will be able to work seamlessly.

cat ~/.ssh/id_ed25519.pub | ssh rob@printserver.local 'mkdir -p ~/.ssh && cat >> ~/.ssh/authorized_keys'

This is one long command. For the record, cat is a command to copy files, I sent mine using the username rob and to the device printserver. You will probably need to change your command. This pre-supposes that you already have keys on your computer to send. You can use the command ssh-keygen on your computer to set that up first if you need to.

If you have done everything right you should be able to login using the ssh command we saw at the top of the post and not be asked for a password. Which is nice.