Table 1 Multiple criteria evaluation/semi-quantitative scoring decision matrix
From: An evaluation of inexpensive methods for root image acquisition when using rhizotrons
Method | Smartphone application | Flatbed scanner | Handheld scanner | Time-lapse camera | Transparent sheet |
|---|---|---|---|---|---|
Image quality | *** High | *** High | *** High | * Low | – |
Deformation | *** | *** | *** | ** | ** |
 Length | No | No | No | No | No |
 Diameter | No | No | No | Yes | Yes |
Time taken | **** | ** | *** | **** | * |
 For 1 rhizotron | 40 s | 12 min | 1 min | 0 s | 12 min |
 For 8 rhizotrons | 7 min | 96 min | 16 min |  | 95 min |
Cost | ** Phone100–700€ Apps free | ** 150 € | ** 80 € | * 190 €/rhizotron | **** |
Usage in field | **** Easy/1 person | ** Difficult/2 persons | *** Easy/1 person | *** Autonomous | * Difficult/1 person |
Accessories | *** No | * Yes/battery and PC | *** No | *** No | *** No |
Time between visits | ** 2–4 weeks | ** 2–4 weeks | ** 2–4 weeks | *** 4–5 months | ** 2–4 weeks |
Time to treat images before analysis | *** 0Â s | * 3.30Â min/image | * 4Â min/image | * 3Â min/image | *** 0Â s |