While the Bugcount One ATP Analyzer produces analytically equivalent measurements to the PhotonMaster, this article addresses performance comparability for customers transitioning from the legacy PhotonMaster luminometer to the new Bugcount analyzer and considers two possible scenarios:
1. Observing slight differences in results from the same test
2. Observing significant differences or inconsistent results from the same test
(Read our validation-testing analysis and comparability guide here.)
Scenario 1:
Why do I see slight differences in test results between my PhotonMaster and the Bugcount analyzer when running the same test?
Small differences between instruments are normal and expected when comparing readings from two separate devices—even when they are measuring the same sample.
The important thing to know is that the Bugcount analyzer and the PhotonMaster are designed to produce equivalent analytical results, so your historical data remains valid and comparable.
Both instruments use the same best-in-class photomultiplier sensor technology, which is the core component responsible for detecting ATP signals. Because of this shared detection technology, they provide the same sensitivity, dynamic range, and measurement performance.
During internal validation testing, both instruments were tested side-by-side using UltraCheck calibration standards across the full measurement range. The results showed a near-perfect 1:1 relationship between the PhotonMaster and the Bugcount analyzer, with a correlation coefficient of R² = 0.99. This means the instruments respond to ATP concentrations in the same way across all tested levels.
However, like any two instruments, minor variation can occur due to normal factors such as electronic noise, sample handling, or slight differences in instrument calibration. These small variations do not affect the overall interpretation of results and fall within expected instrument repeatability.
In short:
- The Bugcount analyzer produces analytically equivalent results to the PhotonMaster.
- Historical PhotonMaster data can still be compared directly with Bugcount analyzer test results.
- Small differences between individual readings are normal and occur with any laboratory instruments.
Scenario 2:
Why do I see a significant difference in test results between my PhotonMaster and the Bugcount analyzer when running the same test?
In the case of any testing instrument, abnormal or inconsistent readings can occur due to various factors, such as electronic (static) interference, sample handling and/or dirt or residue buildup.
For more information on troubleshooting and maintenance of your device, please refer to our supplementary guidance below:
- PhotonMaster – Troubleshooting and Maintenance
- Bugcount One ATP Analyzer – Troubleshooting and Maintenance
If issues persist on either device after completing the steps noted above, please contact technical support at help@luminultra.com for further assistance.