A kitchen chair beside a wooden table. Photo: Shixart1985, CC BY 2.0, Wikimedia Commons.
The chair was a $39 beech kitchen chair with five back spindles and a seat 17.5 inches off the floor. It got photographed in a Columbus kitchen on Sunday 2 November between 2:05 and 2:53 pm with a Pixel 8 on Android 15, and five apps plus one browser tab had a go at turning the photos into a model. Two of them returned a chair. One returned a chair with three legs. One returned a JPEG that wobbled when the phone tilted. One put an animated dinosaur on the floor tiles and asked for $7.99 a week.
2:05 pm, Kiri Engine, 71 photos
Two slow circles round the chair, one at seat height and one from about chest height, gave 71 photos in six minutes. The app's coverage map showed a gap under the seat, which is where the phone cannot go without lying on the floor, so the gap stayed. The upload was 48 MB and took 1 minute 40 seconds on home wifi. Processing on Kiri's servers took another nine minutes, long enough to make a coffee and come back.
The model that came back had 392,000 triangles and a texture that showed the pencil mark on the left front leg. The underside of the seat was a hole. The two rear legs had fused into one flat slab from the knee down, since the phone had photographed them against a white wall from most angles and the software could not tell one round painted leg from the other. The export menu listed OBJ, GLB and STL, and the GLB came out at 58 MB.
2:21 pm, RealityScan, 54 photos
Epic's app colors the chair green as coverage builds, and the chair was mostly green after 54 photos and four minutes. Processing took eleven minutes. The texture was the sharpest of the afternoon, down to the grain in the seat, and three of the five back spindles were missing. Two small patches of glossy varnish on the seat came back as dents, since a reflection moves between frames and the software reads a moving highlight as a change in shape. Export went out through an account sign-in and a GLB arrived in the downloads folder eight minutes later.
2:36 pm, Polycam, 62 photos
Polycam's photo mode took the 62 photos, processed them in the cloud in six minutes, and showed a clean seat and four separate legs with no spindles at all, the whole back rendered as a smooth curved panel. The triangle count was 210,000. The GLB export sat behind a seven-day Pro trial on this account, which was declined at 2:43, so this one never left the app.
| App | Photos | Minutes to a model | Triangles | Legs | Spindles of 5 | Seat underside |
| Kiri Engine | 71 | 17 | 392,000 | 3 (two fused) | 5 | Open |
| RealityScan | 54 | 15 | not shown | 4 | 2 | Open |
| Polycam | 62 | 13 | 210,000 | 4 | 0 | Open |
2:47 pm, one photo in a browser tab
The last photo of the afternoon was IMG_2117.jpg, 12 megapixels, taken from a front three-quarter angle at seat height with the chair pulled 4 feet off the wall. It went into FurniMesh from Chrome on the phone at 2:47 and a chair came back at 2:50, with the kitchen floor already removed from behind it. The file was 46,800 triangles and 2.9 MB as a GLB, with four separate legs, five spindles and a closed seat underside, and the download list offered GLB, OBJ, SKP and BLEND. The trial on a new account covered about ten generations.
The far side of the seat showed wood grain running at ninety degrees to the near side. The photo had never shown the far side, so the grain there was invented, and the seat came in 0.4 inches too deep against a tape measure. Typing the real seat height, 17.5 inches, into the model after download scaled the rest to within a quarter inch on width.
2:53 pm, the two that were never going to make a model
The app with “Scanner” in its name had 4.8 stars, a store page of nothing but camera-feed screenshots and no file format named anywhere in 1,200 words of description. It opened on a camera view, placed a green dinosaur on the tiles, and showed a $7.99 a week subscription screen before any button that might have produced a file. The other one took a single photo of the chair and returned the same photo with a parallax effect, so the chair's front legs slid across the background as the phone tilted. Its share menu offered JPEG and MP4. Both got uninstalled at 2:53.
Monday morning, on a laptop
Blender 4.2 opened the Kiri and RealityScan GLBs and the single-photo GLB without complaint. SketchUp Free, in a browser, opened the SKP from the single-photo download and refused the GLBs, which is normal for the free version. Google's model viewer on the Pixel placed any of the GLBs on the kitchen floor through the camera, at whatever size the file happened to be.
Every file arrived at the wrong size. The Kiri model was 2.3 times life size, the RealityScan model 1.9 times, the single-photo model about 0.6 of it. One typed dimension fixed each of them in under a minute. The Kiri model then needed twenty minutes in Blender to split the fused legs and cap the seat. The RealityScan model needed three spindles drawn by hand. The single-photo model went into a room scene as it was, with a note on the file that the far-side grain was a guess.
| Model | Size on arrival | Cleanup before use | Time to a usable chair, total |
| Kiri Engine | 2.3x | Split legs, cap underside | 37 minutes |
| RealityScan | 1.9x | Draw 3 spindles, fill varnish dents | 41 minutes |
| Polycam | not exported | Trial declined | none |
| Single photo, browser | 0.6x | Type one dimension | 4 minutes |
The afternoon split into thirty minutes on three photogrammetry apps, six on one browser tab, and twelve on a dinosaur and a wobbling JPEG. Two usable chairs, one of them with a texture worth keeping and one of them finished before the coffee was.
