<< Pissin Hot Precision

Open source // GroupLab test set

Send me a photo of your target

No account, no email, no follow up. Pick the photos, tick one box, done.

What this is for

GroupLab is an open source program that measures group statistics from a photograph or a scan of a target. Extreme spread, mean radius, the whole set, worked out from the picture instead of from a caliper and a pencil.

It works fine on a flat scan. It falls over on photographs, which is a problem, because a photograph is what almost everyone actually has. Targets are never flat when they are mounted. They bow, they curl, they flap in the wind, and the software has to understand that surface before it can measure anything on it.

Right now every test image in the project came from one person, at one range, shot with one phone. That is not a test set, that is a habit. Code written against it will work beautifully on my targets and fall apart on yours.

What is actually useful

The whole target, still attached to whatever you shot it on. Do not take it down and flatten it out first. Mounted and slightly bent is the hard case, and the hard case is the one worth having.

Bad photos are more useful than good ones. This is not a gallery. A target shot at a slight angle, in flat grey light, with a shadow across one corner, bowed in the middle, is worth more to me than a perfectly square well lit one. If it looks like the software might struggle with it, that is exactly the one to send.

Send the original off the camera roll. Not a screenshot, not a crop, not one you sent yourself through a chat app. The original file carries the camera and lens data, and the software uses that to correct for lens distortion. Screenshots and crops throw it away, and it cannot be recovered afterwards. A cropped photo is worse than no photo, because it looks usable and is not.

Everything here is optional except the consent box. Answer what you can be bothered to answer and leave the rest.

Yes / No

A whole paper target mounted on a cardboard backer, photographed square on with space around all four edges.
Yes, like this. The whole target, still stapled where you shot it, with a bit of room around it in the frame.
A target photographed too close, with arrows pointing to the left, right and bottom edges where the target runs off the frame.
So close. The arrows show where the target runs off the edge of the picture. Step back a foot and get all four edges in.
A tight close up of a single group of bullet holes, with none of the surrounding target sheet visible.
Not just the group. I need the whole sheet, not one hole.
A phone screenshot of a target photo, with the phone interface visible around it.
Not a screenshot. It has already lost the camera information, and there is no way to get it back.
A target photo that has been through a messaging app, visibly blocky from recompression.
Not one that has been through a chat app. Recompressed, and the lens data is gone.

Upload

Your photos
Drop photos here Up to 10 files, 30 MB each, 90 MB a submission. JPEG, PNG, HEIC, TIFF or PDF.

    Optional. Skip any or all of these.

    Please crop out anything you would not want public: names written on the target, faces, license plates. If you would rather your photos were not published at all, tick the box below and they will only ever be used for testing on a private machine.