Reevaluating Night Vision Modeling: NVIPM vs. TTP
A technical analysis of the U.S. Army’s performance metrics and the need for validated models.
Validated Data
Explore 76 field tests supporting the TTP model.
Technical Accuracy
Understand the psychophysical foundations behind image quality metrics.
Model Comparison
See why NVIPM lacks validation and misuses TTP data.
Our Mission
We are presenting this platform as a technical archive and educational resource to clarify misconceptions surrounding the U.S. Army’s Night Vision Integrated Performance Model (NVIPM) and to defend the scientific integrity of the original Targeting Task Performance (TTP) metric.
Led by R.H. Vollmerhausen of RHV Electro-Optics, LLC, this site is dedicated to:
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Presenting peer-reviewed, field-tested validation of the TTP model
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Addressing unsupported claims made in recent military publications
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Providing figures, data, and references for engineers, analysts, and researchers
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Promoting technical accuracy in defense acquisition models
This is not just a critique — it’s a call for scientific accountability and a resource for professionals in the fields of electro-optics, vision modeling, and defense technology development.
What This Research Covers
.Breakdown of TTP vs. NVIPM metrics
.Why validation matters
.Summary of key findings and recommendations
Figures
Metric Values vs. Range
Figure 3
PID Task Illustration
Figure 6
PID for Tracked Vehicle Target Set
Figure 24
What did the current Army modelers change?
- The original TTP IQM was a frequency domain model that compared eye threshold at each frequency to the spatial frequency content of the target at each spatial frequency.
- Eye threshold is measured by vision scientists and called the Contrast Threshold Function (CTF).
- A single frequency is a sine wave of infinite length, but vision scientists have discovered that between seven and eleven sine wave periods are enough to get an accurate threshold measurement.
- Also, most researchers measuring CTF ensure that the eye is adapted to the display luminance, so even given that eleven sine wave periods are presented, the display luminance is made the same as the sine wave pattern over a large area.
Conclusion
As can be seen by examining Eq. 1, CTFsys is a critical factor in the calculation of TTP values. The original TTP model, validated with 76 experiments, models imagers in the frequency domain and accurately predicts target acquisition performance under various conditions.
In contrast, the NVIPM has only been tested against three of these experiments and lacks full validation. The model makes changes to critical metric inputs (e.g., target vs. display angle) without explanation and relies heavily on dismissing TTP rather than substantiating its own predictions.
Numerous journal articles now cite NVIPM using the validation data from TTP—without justification. This practice not only misrepresents technical facts but also undermines years of scientifically grounded development.
“The lack of recognition of the validation of the original TTP IQM can be laid to simple ignorance or lack of interest.” — R.H. Vollmerhausen
We conclude that the NVIPM has not been thoroughly validated, and its adoption over the original TTP is both technically unsupported and institutionally concerning. Trust in scientific integrity and transparency is essential—especially in defense modeling.