My new Android darkroom assistant

[SchwinnParamount]

So I was developing a batch of 8x10 negs in a tray the other night. As you know, the room had to be pitch black. Fine. The darkroom clock I watch when I develop roll film was now invisible. Oops!

I needed someone to watch a clock for me and tell me when to agitate my film and when to stop. Nobody in my house is willing to stand outside of my darkroom door, watch a sweep second hand, and shout "Start", "Agitate" (or "Shake it baby"), or "Stop", while I work feverishly on my film in the dark.

And then my eyes took in my innocent little Samsung Galaxy tablet on the table. You know (I thought), I can make that thing talk on command. What if I wrote an Android app that let me define a set of commands, intervals timing, and total intervals. No problem. Next, make it bark commands at me in a cute female voice on queue. Again, no problem. Ok, but the damn thing has to be in my darkroom with me and radiate no light while the app is running. Again, no problem.

But then, how do I start the timer on the app in the dark with my hands deep in a tray of water pre-soak? Ok, I'll make the app listen to my voice and wait until I speak the appropriate "Now, gosh-darn it, NOW!" command. Again, no problem.

The result: I've created a very simple little app that waits until I tell it to start, and then prompts me via voice to start development, agitate, and stop development. I can even create a list of unique agitation patterns (film/developer combos) to use for different films.

I'll be dogfooding my own app in my darkroom in the next month. Anyone else her on APUG who has an Android device, develops large format film in the dark, and needs an automated talking stopwatch?

 

[Peter Schrager]

sure

 

[banandrew]

I don't need it but it sounds like an awesome idea, love to install it and try it out, help you find bugs. Are you planning to put it up on the play store?

 

[Oscar Carlsson]

Last time I developed sheet film I used the massive dev chart and put it in a cupboard below the tanks, and no stray light fogged the negatives that I could detect. It was not optimal, and I'd very much like a voice controlled (non-human) help like this. I use android and would be willing to test.

 

[Doremus Scudder]

"I'm sorry Dave; I can't let you agitate like that..."

 

[SchwinnParamount]

Give me a couple of weeks to get my unit testing done. Meanwhile, i will be asking thread readers about your opinion of some potential features.

 

[SchwinnParamount]

Ok, so after I pick the film/developer combo from the list I built in the app, it turns off its UI and goes black. Meanwhile, it listens for me to say "Start". When it hears that word, it starts a countdown from 30. At zero, it assumes I've moved film from the water soak bath to the developer. The app says "Ready?" and then "Start". At the pre-defined interval, it says a word (Presently, "Shake it, baby"... yeah I know. REALLY LAME), but I need to find a cool word for it to say that prompts me to agitate film. When the development time is up, the app says "Stop" The app doesn't light up again until I've physically touched the screen.
I still need to prompt for stop bath timing and fix bath timing. Once that's done, then I'll be ready for you folks.

 

[SchwinnParamount]

Getting much closer. Now the app makes the Android tablet sit quietly in the darkness while I unload my film holders and get a stack of film ready for the presoak. It listens to my voice an when I command, it starts a timing sequence from presoak to dev, to stop, to fix. I created a database (stored on the device for the moment) that lets me configure a timing sequence for each film/developer combination I use.

The tablet prompts me with a female voice to agitate...etc. Not only that, but it tells me what each step in the process is.

I've also coded the app to force the tablet display to go dark while the timer is running. This means I don't need to hide the device in a drawer... it is emitting no light. Once the develop sequence is complete, I can tap the tablet screen and it comes back to life.

 

[tih]

What happens if someone calls your phone (or if some other app decides it wants to notify you of something)?

 

[Oscar Carlsson]

I would put the phone/tablet/etc in flight mode before attempting anything.

 

[SchwinnParamount]

I'll be specifying an Android tablet with no phone functionality for the app. That being said, you will be able to run it on your Android phone just as easily. Oscar is right about the flight mode though. I've only been doing Android development for a year or so. This means I probably don't know all of the capabilities of the Android platform, but I believe I don't have the capability of programmatically shutting off phone notifications. With that, I'll need to rely on the user to do that before starting the timer.

 

[SchwinnParamount]

If you have an Android table then use that for the app. Otherwise, as Oscar says, put the phone in flight mode. I'll be testing the app on a couple of devices and a fair number of emulators. When the app is released and you try it on your device, be sure to open any issues on the GitHub repository where I'll put the source code.

 

[SchwinnParamount]

I've also decided to hook the app to Microsoft Office 365 so that if you have a Office account, you'll be able to connect to O365 through the app. Why is that a big deal? I am going to sell a version of the app (basic edition is going to be free) that sends film development data to your O365 OneDrive folder and drops the data into an Excel spreadsheet that you save there. You'll be able to see your own film development stats from a browser on any computer. It'll be secure of course.

The next question is: what sort of development statistics would you want to keep?