BYgo is a light planning tool for photographers who work outdoors - documentary, street, travel, analog. It reads the weather conditions for any city and translates them into a shooting brief: what to look for, when to go out, which photographers built careers working in exactly this light.

It is not a weather app. Weather apps tell you it will rain. BYgo tells you whether the rain is worth shooting in, and what to do about it if it is.

Type a city name, select a date or date range, and press Search. BYgo fetches the conditions and returns a full assessment - light quality rating, golden hour windows, shadow quality, film recommendations, camera settings, and a shooting brief with photographer references.

No account required. No setup. Just a city name.

Any city that appears in the Open-Meteo geocoding database, which covers virtually every populated place on earth. If BYgo cannot find your city, try the nearest large town or use the Use My Location button for wherever you are standing.

Not yet. BYgo runs in the browser and is designed to work on mobile - the tool is fully responsive. A dedicated app is on the roadmap. In the meantime, you can add BYgo to your home screen from your browser's share menu for a near-app experience.

The shooting brief is BYgo's editorial layer. Rather than showing you raw data, it translates the conditions into specific shooting scenarios - what to look for, what to prioritise, and which photographers worked in exactly this quality of light.

The brief has two modes: Natural Light and Artificial Light. Natural Light covers available light scenarios. Artificial Light covers flash, reflectors, and continuous LED approaches for the same conditions.

BYgo assesses three factors: weather code, cloud cover, and precipitation probability. These are weighted and combined into a five-tier rating: Exceptional, Excellent, Good, Moderate, and Challenging.

The rating reflects photographic quality, not comfort. Fog at dawn is Exceptional. A clear midday sky in summer is Good at best - too much contrast, too much harshness. BYgo's ratings will occasionally disagree with your instincts. That is intentional.

Exceptional - rare conditions. Fog, mist, extraordinary light. The kind of day photographers remember. Go out immediately.

Excellent - heavy overcast, diffuse and even light, generous latitude. Excellent for documentary and portrait work.

Good - clear sky with usable golden hours morning and evening. Avoid midday.

Moderate - variable conditions. The light will change. Worth going out with adjusted expectations.

Challenging - heavy rain, storm, or conditions that make sustained outdoor work difficult. The Studio tab may be more useful today.

The time slider lets you explore what the light is doing at any hour of the searched day. Drag it to a specific time and BYgo tells you which light condition is active at that moment - blue hour, golden hour, soft light, harsh light, mixed light, or night - along with what to look for and which photographers worked in that quality of light.

The slider initialises at the current local time for the searched city if you are searching today, or at solar noon for a future date. The colour gradient along the track shows the light quality across the full day at a glance.

Blue hour - cool, flat, and even. Pre-dawn and post-sunset. Short window, atmospheric quality.

Golden hour - warm, directional, low angle. Long shadows. The window most photographers plan around.

Soft light - heavy overcast. The sky becomes a softbox. Consistent and forgiving all day.

Harsh light - midday overhead. High contrast, hard shadows. Difficult for portraits, useful for graphic work.

Mixed light - partly cloudy. Variable quality. The interesting moments are brief and unpredictable.

Night - after civil twilight. Artificial light only. City lights, neon, flash territory.

The brief is partly randomised within each condition category. There are dozens of scenarios per condition - BYgo selects four each time. The conditions determine which pool of scenarios is relevant; the selection within that pool varies. This is deliberate. Searching the same city on the same day twice should not return identical advice.

Single Day gives you the full assessment for one specific date - light windows, brief, shadows, film recommendations, camera settings.

Date Range shows you a calendar of up to 16 days with quality ratings for each day, a best days list, and a months grid showing historical cloud cover. Click any day in the calendar to see the full assessment for that date.

When you search a date range, BYgo identifies the highest-rated day in that window and loads its full data automatically - light windows, brief, shadows, film, camera settings. The Best Day label appears next to the date header so you know which day you are looking at. Click any other day in the calendar to switch.

BYgo uses Open-Meteo for forecast data, which aggregates from multiple meteorological models. Accuracy is good for 3-5 days, reasonable for 7-10, and speculative beyond that. The 16-day forecast is the outer limit of what Open-Meteo provides and should be treated as planning guidance rather than a firm prediction.

Historical cloud cover data comes from the Open-Meteo archive spanning 2021-2023 and reflects long-term averages rather than specific dates.

Up to 16 days for specific forecast data. For anything beyond that, the Best Months section in the Overview tab shows historical average cloud cover by month - useful for planning trips weeks or months in advance.

The light quality assessments, golden hour windows, and shadow data are equally useful for video work. The film stock recommendations and camera settings are photography-specific and will not apply directly. The shooting brief scenarios are written for still photographers but the underlying logic - when the light is doing something worth capturing - translates to any visual medium.

BYgo's editorial voice is built around documentary and street photography, but the tool itself is useful for any outdoor photography. The light windows, shadow quality, and film recommendations are relevant regardless of what you are pointing the camera at. The shooting brief scenarios will lean toward urban and human subjects - landscape photographers may find the light data more useful than the brief copy.

Yes. BYgo's Challenging rating is an honest assessment, not a prohibition. Some of the most compelling photography happens in difficult conditions - rain reorganises the street, storm light is dramatic, overcast after heavy rain is beautiful. The brief for Challenging conditions is written specifically for photographers who go out anyway. Check the Artificial Light tab if you want options for supplementing what the sky is not providing.

Yes. The share bar at the bottom of each tab gives you options - copy a text summary, share to X/Twitter, Facebook, or WhatsApp, save as an image, or add the shooting window to your calendar. The image export includes all six light condition windows and the day's assessment. Useful for sending a visual summary to a collaborator or client.

When you search today's date, an orange button appears at the top of the Overview tab. Tap it to open a panel where you can upload one or two photographs taken right now, outside, wherever you are standing. BYgo analyses the actual light visible in your images and updates the assessment - Brief, Light, Shadows, Film, and Camera tabs - to reflect what is really happening rather than what the forecast predicted.

Weather data is good. What you can see with your eyes is better.

Wide shot - point your camera at the sky and surroundings. This shows cloud cover, light direction, and ambient conditions. Include as much sky as possible.

Close-up - photograph a surface, a wall, or a face in the available light. This shows shadow quality and hardness. Optional, but useful - shadows tell BYgo whether the light is directional or flat, hard or soft.

Both images should be taken outside, in the current conditions, at the time you want the assessment for.

The analysis uses the time to contextualise what it sees. A bright sky at 06:30 means something different to a bright sky at 13:00. The time defaults to the current time, which is correct if you are uploading photos taken just now. Change it if you are uploading photos taken earlier in the day.

No. Your photographs are converted to a compressed format in your browser, sent to the analysis server, read once, and immediately discarded. They are never written to disk, never stored in a database, and never seen by anyone. BYgo has no interest in keeping your images.

BYgo sends your images to a vision model which reads the light conditions visible in the frame - cloud cover percentage, light condition category, shadow quality, shadow direction, and colour temperature. It returns a structured assessment which BYgo uses to update the Brief, Light, Shadows, Film, and Camera tabs.

The model is instructed to trust what it sees rather than guess from the time or location. A photo of heavy overcast at noon will update the assessment to soft light regardless of what the forecast said.

A few possible reasons. The wide shot may not have captured enough sky - try pointing the camera higher. A very processed or filtered image may mislead the model. Indoor or studio photos will return unpredictable results. Stock photos or images not taken in your current conditions will not work at all.

The analysis is designed for unprocessed photos taken on the spot. The closer your images are to what a RAW file would show, the more accurate the result.

Yes. After the analysis runs, a badge appears showing Results based on your photos with a Reset to forecast link next to it. Tap it and all tabs revert to the original forecast-based assessment. The photos are cleared from the panel and you can run a fresh analysis if you want.

Because it only makes sense to upload photos of current conditions. Uploading a photo from last Tuesday to refine a forecast for next Friday would produce a meaningless result. The feature is intentionally limited to single day searches for today.

Film recommendations are matched to the current conditions - weather code, cloud cover, and precipitation. Each condition maps to a set of film stocks across three categories: black and white, colour negative, and slide/reversal. The recommendations are opinionated but not prescriptive. You are free to disagree with them.

Pushing film means rating it at a higher ISO than the box speed and developing for longer - useful in low light when you need more speed. Pulling does the opposite - rating lower and developing less - useful in very bright conditions to reduce contrast. BYgo notes push and pull recommendations where the conditions suggest it. Your lab needs to know the push/pull amount before they develop.

The EV table is a starting point based on the Sunny 16 rule, adjusted for today's conditions. It will get you in the right ballpark. Your meter, your specific film, and the exact conditions you are shooting in will give you more precise readings. In unfamiliar light, bracket. Always.

Starting points. BYgo gives you settings by lens type - wide, standard, telephoto - based on the conditions. These are reasonable places to begin, not finished answers. Your camera, your subject, your instincts, and the specific moment will require adjustments. BYgo is under no illusion that it knows better than you what the right exposure is once you are standing in front of the thing.

The Studio tab is its own section in the navigation. It shows a condition-matched editorial brief explaining whether a studio makes sense given today's outdoor conditions, and what to look for in a studio if you decide to go in. Click the Find a Studio button to search for photography studio rental spaces within 10km of the searched city using Google Places.

Results include name, address, rating, and open/closed status. You can filter by open now, minimum rating, and sort order.

The Film tab has three sub-tabs: Overview (film stock recommendations), Film Lab, and Film Shop. The Camera tab has three sub-tabs: Overview (camera settings), Camera Shop, and Camera Rental. Click the relevant sub-tab and then the search button to find nearby options using Google Places within 10km.

Each store type has its own daily search limit, so looking up a film lab does not consume your camera rental searches.

Results come from Google Places and are not vetted by BYgo. The search keyword - photography studio rental hire space - is designed to surface bookable photography spaces rather than recording studios or hair salons, but results will vary by city. Always check the studio's website before booking. The Google Maps link at the bottom of the results opens the full list.

Google Places coverage varies significantly by city. Major cities return reliable results. Smaller cities may return fewer relevant results or mix in unrelated businesses. If the results are not useful, the See full list on Google Maps link will give you a broader search you can refine manually.

Film Lab - places that develop and scan film. C-41 colour negative, E-6 slide, and black and white processing. Search for a lab if you have exposed film that needs developing.

Film Shop - places that sell film stock. Search for a shop if you need to buy film before you go out.

Some places do both. Check before you go.

No. BYgo works without an account. Type a city, get results. No sign-up, no email address, no password.

Free users can perform 3 city searches per day. Each store or studio lookup - film lab, film shop, camera shop, camera rental, studio - has its own separate limit of 3 per day. Applying filters to existing results does not count against your limit.

A prompt appears explaining that you have reached your daily limit. You can return tomorrow when the limit resets, or unlock unlimited access. After hitting the limit on consecutive days, BYgo will suggest an upgrade.

Because BYgo does not require an account. IP-based tracking is the only way to apply fair usage limits without asking you to register. It is not perfect - shared networks may affect limits - but it is the least intrusive approach available without a login system.

The limit is enforced server-side by IP address, not by browser cookies or local storage. Clearing your browser will not reset your daily limit.

The intention is yes. BYgo is built around the idea that useful tools should be accessible. A free tier with reasonable limits will remain part of the product. What changes over time is what is available on each tier.

BYgo is free to use with daily limits. No credit card required. Unlimited access is available as a paid upgrade.

BYgo was built by Taushik Mandal, a photographer and indie builder based in Barcelona. It started as a personal tool - something to answer the question of whether the light was worth going out for before lacing the shoes - and became something other photographers found useful.

For specific dates more than 16 days away, the forecast data will not be available yet. Use the Best Months section in the Overview tab instead - it shows historical average cloud cover by month, which gives you a reliable picture of what to expect. Come back closer to your travel date for the specific forecast.

Email hello@bygo.app with as much detail as you can - what you searched, what you expected, and what happened instead. Bug reports are taken seriously and responded to. Incorrect editorial content - a wrong photographer reference, a broken link - is especially useful to know about.

Email hello@bygo.app. Feature requests, complaints, and suggestions about the photographer references are all welcome. BYgo is built by one person and the feedback loop is short.