Taking your weekly scan
A scan is close-up photos of your scalp, one area at a time: the front and the top every week, and all five areas once a month. It takes a minute or two, and you do it once a week.
The week between scans matters. Hair changes slowly, and photos taken a few days apart mostly show the difference in lighting rather than the difference in your hair.
Before you start
Three things make a bigger difference than anything else:
- Even, indirect light. Daylight in a room, not a bright lamp overhead and not direct sun. Harsh light casts shadows between hairs, and shadows read as gaps.
- Dry, unstyled hair. Product and water clump hairs together, which makes thinning look worse than it is.
- The same conditions each week. Same room, same time of day if you can. What is being measured is the change, so anything that changes alongside your hair makes that harder to see.
It helps to hold your phone above your head rather than trying to see the screen. You will not be able to watch what you are capturing for most of the shots, which is expected - the guidance on screen tells you where to aim.
Taking the photos
Start the scan
Open a scan from Home. You will be asked for one area at a time. Your very first scan opens by itself right after you join, and if we do not know yet whether to read your hair on the male or the female scale, it asks that one question first.
Photograph the area shown
Follow the guide on screen for where to point and how close to hold the phone. You can take the photo with your camera or pick an existing one.
Wait for it to be accepted
Each photo is checked before you move on. When it is usable, the scan advances to the next area on its own.
Retake anything that was not usable
If a photo cannot be used you are told why - too dark, too blurry, too far away, or something in the way. Retake that one area; the ones already accepted stay.
Finish and wait
Once the front and the top are in, Send for analysis opens. Add your sides and back first if you like, then send. The analysis can take up to a minute.
“Accepted for analysis” does not mean “your hair looks good.” It only means the photo is sharp enough and lit well enough to read. It is a comment on the photograph, never on your scalp.
Which areas each scan asks for
| Scan | Asked for | Optional |
|---|---|---|
| Your first scan | Front and top | Sides and back, which you can add from your result until your next scan opens |
| A weekly scan | Front and top | Sides and back |
| Once a month (your 5th, 9th, 13th scan and so on) | All five | You can skip the sides and back that month, and we ask again next month |
The front and the top are where your stage and your progress are read. The sides and back change slowly; once a month keeps every scan comparable with the next.
If the camera will not start
Take photo opens a camera view inside the app. When it cannot start, it says why:
| What it says | What it means |
|---|---|
| Camera permission denied | Your browser is blocking camera access for this site |
| No camera detected on this device | There is no camera to use - usually a desktop without a webcam |
| Camera API not available in this browser | This browser cannot capture inside a page at all |
Try again is there for the first of those: change the permission in your browser settings, press it, and the camera starts without your having to leave the scan.
And you can finish the scan without the camera at all. Close the camera view and use Library on the area card instead. That opens your phone’s own photo picker - which on most phones also offers taking a new photo - and anything chosen that way goes through exactly the same check. It is not a lesser route: it is the one the scan is built around.
For a blocked permission, the order matters: allow camera access in your browser settings first, then press Try again. The button asks your browser a second time, and a browser that has already been told no will keep saying no until the setting itself changes - so pressing it before changing anything will simply fail again.
If we could not check a photo
There is a third outcome besides accepted and unusable, and it is worth telling apart: sometimes the check never runs at all. The connection dropped, or the service was briefly unavailable. You will see “We could not check that photo just now”, and it will tell you your photo is saved.
Use Try again rather than retaking. Nothing is wrong with the photograph, so a new one will not help - the button re-sends the one you already took.
This is deliberately not worded like a rejection. A rejection is a verdict on the photo and asks you for a better one; this is us not having looked yet. Being told your good photo was no good, retaking it, and being told the same thing again is the exact outcome the different wording exists to prevent.
When a photo turns out unusable afterwards
Occasionally a photo passes the initial check but cannot be read properly during analysis. When that happens that one area is left without figures for the week, and your scan is still saved with the rest.
You will see it marked as unclear rather than shown as a low score. There is a real difference: a low number means “we read this and it is low”, and unclear means “we could not read this”. Showing the first when we mean the second would be inventing a result.
One unclear area in a week is not worth re-doing the scan for. If the same area is unclear several weeks running, it is usually the angle or the lighting in that spot - worth changing something about how you capture it.
If you leave part-way through
What survives depends on whether you had sent the scan yet, and the difference is sharp:
| When you left | What happens |
|---|---|
| While still taking photos | The photos are not kept. Reloading starts the scan again |
| After Send for analysis | The analysis keeps running on our side, and the app picks it back up |
Once a scan is sent it does not need you to stay. Reload the page, open Densy in a new tab, or come back after the browser crashed, and the waiting screen returns on its own. Closing the tab is fine too - the app asks the server whether you have a scan running rather than relying on anything stored in your browser.
Before you send, though, treat the photos as unsaved work. If something interrupts you half way, finish the remaining areas in the same sitting rather than coming back to it later.
What happens next
Your results appear once the analysis finishes. What they mean, and why the numbers can shift, is covered in understanding your results.
From there, tracking change over time covers comparing this scan against an earlier one, and your scan history is where every scan you have taken is kept.
A new scan unlocks seven days after your last weekly one. If the option is not available yet, that is why - the countdown is shown next to it.
Extra scans
An extra scan lets you scan before your weekly scan is due. You earn one by reaching some points levels, and the Densy team can also give you one.
While you wait for your weekly scan, the Next scan card on your dashboard shows Use my extra scan. It asks you once, then the scan works as usual.
- Your weekly scan keeps its day. It still counts from your last weekly scan.
- The extra scan goes on your chart like any scan.
- It earns no points and is not a week of your streak.
- Your scan list marks it Extra scan.
In the phone app you cannot start an extra scan yet; use densy.club in your browser.