2DVD Original Manufacturer Literature (English PDF)
PDF · Manufacturer document
Disdrometers can report size distributions, fall velocity, intensity and type. Calling all of these precipitation accuracy conceals their different meanings. JOANNEUM RESEARCH 2DVD, THIES LPM and 3D Stereo documents illustrate different levels of information.[1–3]
What each output answers
| Output | Main question | Not a substitute for |
|---|---|---|
| Size/distribution | Particle dimensions and distribution | Shape or chemical composition |
| Fall velocity | Motion while crossing the measurement region | All velocity conditions at a fixed height |
| Shape/images | Projected or spatial morphology | Unconditionally accurate true volume |
| Precipitation type | Classification under instrument rules | Independent observation or a universal identification rate |
Principles provide different information
2DVD uses two viewing directions to relate contours and velocity and evaluate shape, orientation and three-dimensional information. LPM uses laser-extinction signals for size/velocity-related outputs and precipitation distributions. Minimum particle size alone cannot rank their accuracy.[1][2]
3D Stereo documentation describes stereo imaging, real-time processing and particle images. Its notes restrict images to the focus area and a maximum of 4 images per telegram. Interpret image retention with these conditions.[3]
Read conditions with the numbers
2DVD velocity accuracy and some resolution information apply below 10 m/s; retain that condition. The 3D identification rate also depends on precipitation conditions and particle characteristics, rather than being an all-situation guarantee.[1][3]
LPM size/velocity bins describe output grouping, not the accuracy of every bin. Software-derived radar-related quantities are not direct radar observations.[2]
Select outputs for the research task
For size–velocity relations, check joint distributions and formats; for morphology, image availability and conditions; for classification, rules and boundaries; for long-term sites, installation, maintenance and status records.
The documents provide no same-sample, same-environment performance comparison. This article explains output types, not which instrument is more accurate, and does not turn application photographs into customer results.
References
- [1] 2DVD Original Manufacturer Literature (English PDF), PDF page(s) 2–3 (file page order). View reference resource
- [2] LPM Original Manufacturer Literature (English PDF), PDF page(s) 2–4 (file page order). View reference resource
- [3] 3D Stereo Disdrometer Original Manufacturer Literature (English PDF), PDF page(s) 1–2 (file page order). View reference resource