Is a timestamp camera photo enough proof if the customer disputes it?

What the stamp does prove

Start with what you actually have. Your crew finished the job, somebody took a picture with an app that prints the date and time in the corner, and that picture is now the whole of your evidence. It is worth more than people in an argument tend to admit.

A stamped photo shows a scene somebody stood in front of. It shows the work in the state the camera saw it: the cut grass, the clean floor, the new part on the unit. It carries a time and often a place, written down when the picture was taken rather than remembered afterwards. A customer asking “did you come?” in good faith is often satisfied by it, and the conversation ends there. It also beats a line in your own software saying the job was closed.

So the honest answer to the question is not “a stamp is worthless.” It is that a stamp is the beginning of a record, and a dispute is the point where someone starts examining everything around it.

The four questions the other side will ask

Once the person paying disagrees, the photo gets read by someone looking for a reason to discount it. That might be the customer, their card company, or whoever reviews the chargeback. Their questions are predictable, and none of them is about the grass.

1. Who set the time? The stamp shows a time. It was printed by the phone or the app that took the picture, on the crew’s side of the dispute. The date a camera writes into the file is metadata, the kind of information that standard metadata tools are built to read, write and edit. That does not make a given photo false. It means the date in the file is something a careful reviewer is entitled to question.
2. Was it taken there, or picked from the gallery? A photo that reaches the office as an attachment could have been taken at the job that day, or a week earlier at another address. The reviewer wants to know which, and what in the file shows it.
3. Has the file changed since? The picture travelled from a phone to a text thread to an inbox. The printed stamp is a picture of a time. Some timestamp apps add their own photo code or a page where a photo can be checked; if yours does, that is where to point a reviewer, and it is worth finding before a dispute rather than during one.
4. Where was the phone? A printed location says what the app wrote. The reviewer wants to know whether anything independent recorded it.

None of those questions accuses anyone of lying. They are the questions any careful reviewer asks of evidence produced by one side about its own work. When the answer to each of them is your account of what happened, the customer is back to weighing your word, which is exactly what they have stopped accepting.

What a record needs to answer them

Now change one input. Instead of the crew taking a picture and sending it in, the office sends the crew a link for the job. The link opens the phone’s camera, live, with the gallery blocked, so the picture is a fresh one from the camera and an older file from the gallery has no way in. The worker installs nothing and signs up for nothing. The clock that dates the photo is the server’s, read as the upload lands, so it belongs to neither the worker nor the office. If the worker lets the phone share its position, that reading travels in with the photo; switch on the setting that requires it and no photo goes in without one. Last, the server computes a SHA-256 fingerprint across the picture, that server time and any coordinates that came with it, so editing any of them afterwards shows up as a mismatch.

One more piece answers the question nobody thinks to ask until a dispute: whose record is this? When the job is one you scheduled, LockProof creates its entry on the server first, then sends the link, so the photo lands in something your office made instead of starting life on somebody’s phone. When a customer wants to see it, you send a link that opens in a browser with no account and expires after seven days.

Be clear about what this leaves to people. A sealed record shows that a live photo came in at a server-set time and has not changed since. Judging whether the work was any good, and whether the picture shows the job on the invoice rather than a similar one, is still a human’s call. A person reviews the image.

What a card processor looks at

When the dispute goes to a card company, the question becomes what a reviewer will weigh. Stripe publishes sample evidence packets for common dispute categories, described as a non-exhaustive list of best practices. For a service the customer says was not received, read on October 28, 2026, the packet asks you to add your communications showing the service’s scheduling date and completion date, show a confirmation receipt that the customer completed the service, include a service session log with when you scheduled it, any reminders sent and notes taken during it, and attach information about the service delivery and fulfillment.

Notice what that list is. It is the record around the work, kept by a system, more than any single picture. A dated photo record sits naturally inside that file. It is one exhibit among several, the outcome is never guaranteed, and nothing here is legal advice. For the full sequence of a response, see the step-by-step chargeback response.

Say the lawn was cut on Tuesday

Here is a hypothetical. Say a lawn crew mows a client’s yard on a Tuesday, and the foreman takes a picture with a timestamp camera app: fresh stripes, a date and time printed in the corner. Two weeks later the client disputes the charge with their card company and says nobody came that week.

The company emails the photo. The reply is short. The time on that picture came from your crew’s phone, the file sat on that phone and then in your inbox, and you are asking me to take your word for when it was taken. Nobody is lying. The photo may be exactly what it looks like. But the company has no record of its own that the photo arrived that Tuesday.

Picture the same visit captured through a link the office sent. The camera opens live, the time comes from the server as the upload lands, and the record is sealed. The company now has a time and a seal it did not set to put in front of the client and the card company. That does not decide the dispute. It gives the honest side something to stand on. For the same idea applied across a whole job, documenting completion across a field-service job walks through it, and proving an image is authentic in the first place covers the separate question of whether an image is authentic at all.

If you are weighing a timestamp camera app against a sealed record for your own crew, timestamp camera apps and a sealed record, compared sets them side by side, and the sample proof record shows what a customer actually receives.