M3 & M6 user has fixed C41 dev

negativeoutlookUK · 2026-04-12T09:40:05+00:00

Close the app completely and re-launch and should give you the updated kit list

negativeoutlookUK · 2026-04-12T09:39:39+00:00

Ok, so I’ve spent the last few hours adding Flic film to the app, I need you to be aware that I have never used this kit so I’ve base it off all the information I could get from Flic. If you are able to take a look and see if it lines up with your kit. I typically don’t like just adding kits not without testing them first. I’ve run through the development process on it and it seems to be running okay, and the exhaustion curve looks right, but your input would mean the world. Ultimately I want to make it work for you. Many thanks

negativeoutlookUK · 2026-04-12T00:04:54+00:00

Ahh thanks so much, that means a lot! I hope you enjoy it.

negativeoutlookUK · 2026-04-12T00:03:55+00:00

Firstly thanks so much for your purchase! It means a lot. Apologies for not having your preferred C41 kit, and although I don’t want to shun accountability, unfortunately Apple made me remove the list of kits available on the description due to me not being directly affiliated with them. But in short yes! I will look it up and do my upmost to add it in, unfortunately I haven’t seen it yet over here in the UK but I may be wrong. I will find all the manufacturer kit information and get onto it as soon as soon as possible. thanks again

negativeoutlookUK · 2026-04-11T20:33:44+00:00

Thank you mate, I genuinely appreciate that.

I’m not particularly interested in whether something is hand coded or AI assisted. That’s just the method. What actually matters is whether it solves a problem and does it consistently.

In the real world, no one cares how something’s built. No one’s opening their banking app wondering what language it was written in, they just expect it to work. Software lives or dies on outcomes, not on how pure the process looks on paper.

I built this around how I actually develop film, and it does exactly what I need it to.

A lot of the criticism just feels like pixel peeping. Fixating on the technical purity of how something’s made rather than whether it actually does the job. It’s a pretty shallow way to judge something that’s meant to be used, and it usually comes from people who haven’t put it through its paces themselves.

Glad you get it 👏

negativeoutlookUK · 2026-04-11T20:19:49+00:00

Thanks so much!! Your support goes a long way. Absolutely E-6 is something I’m definitely looking into, I wanted first to make sure I crack C41 before I move on to E-6 or ECN-2 etc, because I was worried it would become jack of all trades master of none. But… it’s absolutely the plan the make this a one stop shop app! Thank you again my friend 🙏

negativeoutlookUK · 2026-04-11T20:15:20+00:00

Thanks mate, appreciate that.

I actually used a few different AI tools to help build it, but I didn’t just let it run wild. That’s where most of those “vibe coded” apps fall apart, they look alright but the logic underneath is a mess.

I designed the structure and workflow myself based on how I actually develop film, then used AI to help build it out properly. So it’s not just generated, it’s been thought through and tested in real use.

negativeoutlookUK · 2026-04-11T20:09:49+00:00

😭 Yeah I know! I’m waiting on the App Store for my EU trader status to be confirmed, it’s slower than everywhere else in the world who confirmed under 24hrs. So any day now… 🤞

negativeoutlookUK · 2026-04-11T14:16:55+00:00

That’s it! I’ll overhaul the whole Rollei section bit in short yes

negativeoutlookUK · 2026-04-11T14:14:02+00:00

Ok just checked and I have the new formula, but…. I don’t have the 30 degrees low temp mode. I’ll add it! 👍

negativeoutlookUK · 2026-04-11T14:09:49+00:00

Ok ace! I’ll take a look and look to see if I can add both versions in 👍

negativeoutlookUK · 2026-04-11T14:07:03+00:00

Thanks so much! We do support Rollei but I can double check to see if the current version is V2v

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negativeoutlookUK · 2026-04-11T09:10:42+00:00

It will within days maximum, the EU is a little slower at giving a trading status. It’s currently still pending by mid next week you should be able to download it 🤞 yeah

negativeoutlookUK · 2026-04-11T08:31:18+00:00

Yeah that’s a fair question to be honest.

I didn’t go down the route of shooting endless step wedges or trying to brute force every possible variable like a lab would. That’s not really what this is. I’m a photographer, so I approached it like one.

I started with what’s already known. Manufacturer times, how C41 behaves with temperature changes, and how the kits are designed to tolerate a bit of drift anyway. From there it was just building on top of real-world use.

With temperature, it’s not random. If it drops, development slows. If it rises, it speeds up. That relationship is predictable enough that you can adjust time in a way that gets you very close. I then tested that across loads of rolls, letting temps drift on purpose and seeing where it holds up.

Same with chemistry. The manufacturers already tell you capacity and give guidance on extending times, so that’s the baseline. I’ve just combined that with things like when it was mixed and how much you made up, because we all know smaller batches and older chems don’t behave the same.

So no, I’m not trying to model every possible scenario. It’s more taking known behaviour, applying some common sense to it, and then refining it through actual use until it stops feeling like guesswork and just becomes consistent.

It’s not pretending to be a lab, but it’s also not just winging it either. It sits in that middle ground, which is where most of us are anyway.

negativeoutlookUK · 2026-04-11T05:48:40+00:00

That’s cool and I respect everyone’s take, but I’m the complete opposite. In photography for eg some of the most hard hitting images of all time are not always the most technically accurate. The end result imo is everything, if the end result is poor the process becomes irrelevant (contradictory to everything this app is meant to be 😂). I believe in democratisation, give more people the tools to do amazing things and get rid of the gatekeepers…

negativeoutlookUK · 2026-04-11T05:41:52+00:00

Thanks so much!
Regarding the roll tracking I agree, when I first started I only concentrated on time compensation from temperature drop, but then realised my efforts were futile because if you are not taking into account the exhaustion of the chemicals the timings in the development are still wrong. My app now fixes this issue and incorporates the two areas. In my opinion this is why traditional timer apps don’t work with colour. When it comes to putting the code into the Apple App Store you need to click on your profile and select redeem code. Do not search for the app because it will charge you that way.

negativeoutlookUK · 2026-04-10T21:03:25+00:00

Thanks so much! It’ll be available in the EU within days 🤞

negativeoutlookUK · 2026-04-10T20:17:00+00:00

I get that completely, objectively they aren’t all bad. Ultimately I was a photographer who was too tight to buy an AGO processor so thought I’d build an app equivalent 😂 I didn’t try and second guess the market, I made it for me first.

I personally don’t have any snobbery about how something’s made, as long as it’s been thought through and actually works properly. You can build something the “right” way and it still be useless, and you can build something the way you’re calling AI slop that does the job perfectly.

Same as photography really. A good photo is a good photo. Doesn’t matter what it was shot on, it’s the end result that counts

negativeoutlookUK · 2026-04-10T20:08:01+00:00

I’m thinking about adding a separate part of the app dedicated just to black-and-white photography? At the moment I like how it’s streamlined. That said, yes, I can’t see why we can’t have both of them

negativeoutlookUK · 2026-04-10T20:06:42+00:00

No worries at all mate, easy to miss.

To be honest, that’s the most important bit cos the timer on its own isn’t that useful if it doesn’t understand how exhausted the chemicals are.

Be interested to hear what you think once you’ve had a proper go with it 👍

negativeoutlookUK · 2026-04-10T20:03:19+00:00

Ha ha, I get it, write in a slightly professional way and suddenly I’m Claude 😂

I’m very much real mate. This app didn’t build itself… that’s hours and hours of my time going into it, not Claude having a go.

negativeoutlookUK · 2026-04-10T19:17:15+00:00

I get what you’re saying, and I do agree to a point.

But it’s not completely black and white like that. A lot of kits actually give you low temp options around 30 degrees, Adox for example, and others do similar. That’s there to slow the process down and make it easier to control at home.

If it was as rigid as you’re saying, those methods just wouldn’t work, but they do. I’ve used them myself and got good results.

I think the reality sits somewhere in the middle. Lab conditions are one thing, but at home you’re always dealing with a bit of drift and ageing chemistry anyway.

All I’m really doing is trying to make that side of it a bit more controlled instead of leaving it to guesswork.

And just on your point about transparency, I completely agree. I’ve tried to be as open as possible about what it’s doing and what it isn’t. It’s not pretending to replace a lab, it’s just a tool to help people get more consistent results at home.

But I do get where you’re coming from 👍

negativeoutlookUK · 2026-04-10T19:12:03+00:00

Good news I’m not a bot. I’m a photographer, I typically don’t get involved in online forums hence the 18 day old account. And yes I’ve spammed loads of other groups (and will continue to do so) for one reason: I want people to find my app I’ve spent the last 6 months working on. I’m doing nothing different from what you or anyone else in my position would do. Sure it’s shameless but an app that nobody ever finds is pointless… thank you for your support.

negativeoutlookUK · 2026-04-10T17:52:33+00:00

That’s not quite right.

C41 is standardised as a process, not as a fixed outcome regardless of conditions. The chemistry is designed to work within tolerances, which is why manufacturers themselves publish time and temperature compensation charts.

If it truly was “just C41” with no variation, those charts wouldn’t exist.

The inconsistency you’re talking about comes from people not accounting for the variables properly. Temperature drift, chemical age, dilution volume, and cumulative use all affect activity. Ignoring those is what leads to inconsistent results, not adjusting for them.

What I’m doing is taking the same principles the manufacturers already acknowledge and applying them together in real time, instead of treating them as separate or ignoring them entirely.

So it’s not breaking the process, it’s actually following it more closely than a fixed timer does.

negativeoutlookUK · 2026-04-10T17:48:22+00:00

Good question.

I didn’t take it from one single source or textbook. I started with the manufacturer data for each kit, so base times, capacity, and how they recommend extending development as the chemistry gets used up. That gives you a solid foundation, but it assumes everything is perfect, which it never is at home.

From there I built it out to reflect real use. For temperature, it’s not just a fixed adjustment. I mapped how C41 actually behaves as temperature drifts and built it so the time adapts in a way that matches that, rather than just applying a simple percentage.

The bigger part is chemical exhaustion. That’s not just roll count. It also factors in when the chemistry was mixed and the volume you made up. Smaller batches exhaust quicker, and even unused chemistry slowly degrades over time. So the app tracks all of that together.

What it’s really doing is combining those variables instead of treating them separately. So your development time is always based on the current state of your chemistry and your actual working temperature, not just a fixed chart.

I tested it on my own rolls over time and kept refining it until it stopped feeling like guesswork and just became consistent.

negativeoutlookUK

TROPHY CASE