How to Set Emissivity on a Thermal Camera: Noyafa NF-522 Measurement Guide Malaysia
How to Set Emissivity on a Thermal Camera: Noyafa NF-522 Measurement Guide Malaysia
A thermal imaging camera can display impressive temperature patterns, but obtaining meaningful temperature readings requires more than simply pointing the camera at an object.
One of the most important settings is emissivity.
Incorrect emissivity settings can cause infrared temperature readings to differ from the actual surface temperature, particularly when measuring shiny or reflective materials.
The Noyafa NF-522 Thermal Imaging Camera provides adjustable emissivity from 0.1 to 1.0, allowing users to adapt the instrument to different target surfaces.
Understanding how emissivity works can significantly improve thermal inspection results.
What Is Emissivity?
Emissivity describes how effectively a surface emits infrared energy compared with an ideal blackbody at the same temperature.
The value is expressed between:
0 and 1
Many non-metallic, matte and painted surfaces have relatively high emissivity.
Highly polished metallic surfaces can have much lower emissivity and can also strongly reflect infrared energy from surrounding objects.
This is why two surfaces at the same actual temperature may produce different infrared measurement results if emissivity is not considered.
Why Does Emissivity Matter in Thermal Imaging?
A thermal camera estimates surface temperature based partly on the infrared energy it receives.
If the camera assumes the wrong emissivity, the displayed temperature may be inaccurate.
For example, a technician may inspect:
Painted motor housing
Rubber insulation
Plastic electrical component
Oxidized metal
Polished aluminium
Stainless steel
These surfaces do not behave identically in infrared measurement.
Therefore, professional thermal inspection requires the user to understand the target surface rather than simply trusting every displayed temperature number.
Noyafa NF-522 Emissivity Adjustment
The Noyafa NF-522 provides an adjustable emissivity range of:
0.1–1.0
This allows users to select an emissivity value more appropriate for the material being inspected.
For general inspection, the correct setting depends on the target material, surface finish and measurement conditions.
Typical Emissivity Examples
Approximate emissivity values vary according to surface condition, wavelength and temperature.
General examples may include:
Matte painted surfaces: often high
Rubber: generally high
Plastic: often relatively high
Concrete: generally high
Brick: generally high
Wood: generally high
Oxidized metal: often higher than polished metal
Polished metal: often low
These should be treated as general guidance rather than universal fixed values.
For important measurements, refer to reliable emissivity data for the specific material and surface condition.
Why Shiny Metal Is Difficult to Measure
Shiny metal is one of the most challenging targets for infrared thermography.
A polished metallic surface can have low emissivity and high reflectivity.
This means the camera may detect infrared energy reflected from:
The technician
Nearby machinery
Hot equipment
Lighting
Walls
The sky
Other environmental sources
As a result, a bright or hot-looking area on a thermal image does not always mean the metal itself is at that temperature.
Can a Thermal Camera Measure Stainless Steel?
Yes, but care is required.
Bare or polished stainless steel can be difficult to measure accurately because of its low emissivity and reflective nature.
If accurate temperature measurement is required, technicians may need an appropriate measurement technique that provides a known high-emissivity target surface where safe and practical.
The inspection method should always suit the equipment and safety requirements.
Thermal Imaging of Electrical Panels
Electrical inspections frequently involve mixed materials.
Inside one electrical panel, the technician may encounter:
Plastic breaker housings
Painted metal
Copper conductors
Cable insulation
Metallic terminals
Busbars
These materials can have very different emissivity characteristics.
This is why thermal images should not be interpreted only by colour.
A bright-looking metallic terminal and a bright-looking plastic breaker surface may not represent identical measurement conditions.
Compare Similar Surfaces
One useful inspection technique is to compare similar components made from similar materials.
For example:
Breaker A vs Breaker B vs Breaker C
If all three breakers have similar surfaces and operate under comparable conditions, differences in their thermal patterns may be more meaningful.
Likewise:
Motor 1 vs Motor 2 vs Motor 3
Comparison can often provide more practical maintenance information than focusing only on one absolute temperature reading.
Why Thermal Image Colours Can Be Misleading
Thermal colours are visual representations of temperature distribution.
They do not automatically mean:
Red = dangerous
or:
Blue = safe
The colour palette is scaled according to the temperature range being displayed.
A red area in one thermal image may actually be cooler than a blue area in another image if the scales are different.
Always check the actual temperature values and measurement conditions.
Common Thermal Measurement Mistake #1: Wrong Emissivity
Setting emissivity incorrectly can affect temperature readings.
Before relying on the measured value, consider:
What material am I measuring?
Is the surface painted?
Is it polished?
Is it oxidized?
Is it reflective?
What emissivity setting is appropriate?
These questions are particularly important when comparing different materials.
Common Mistake #2: Measuring Reflective Surfaces
A reflective surface may show thermal reflections from surrounding objects.
The technician may even see a thermal reflection of their own body.
Changing the viewing angle can sometimes help identify whether a pattern is caused by reflection.
If the apparent hot spot changes significantly as the inspection angle changes, reflection should be considered.
Common Mistake #3: Ignoring Distance
Thermal measurement is not simply point-and-shoot at any distance.
As distance increases, small targets occupy fewer thermal pixels.
A small electrical terminal may be easy to inspect from close range but difficult to measure meaningfully from far away.
For small targets, technicians should work at an appropriate safe distance that allows the target to occupy sufficient thermal image area.
Electrical safety requirements must always take priority.
Common Mistake #4: Ignoring Environmental Conditions
Thermal inspection can be influenced by environmental conditions such as:
Direct sunlight
Wind
Rain
Nearby heat sources
Reflections
Rapid temperature changes
For building inspection, sunlight can significantly change wall and roof surface temperatures.
For outdoor equipment, wind can cool surfaces and reduce visible temperature differences.
Measurement conditions should therefore be considered when interpreting results.
Common Mistake #5: Measuring Through Glass
Standard thermal cameras generally do not behave through ordinary glass the way visible-light cameras do.
Glass can reflect and absorb infrared radiation.
A thermal camera pointed at a window may therefore display the temperature characteristics of the glass and reflected surroundings rather than the object behind it.
Users should not assume the NF-522 can simply “see through” a normal window.
Common Mistake #6: Assuming Thermal Imaging Diagnoses the Fault
Thermal imaging identifies temperature patterns.
It does not automatically determine the root cause.
For example:
Hot electrical terminal
may require further investigation using electrical testing.
Hot bearing
may require vibration measurement and mechanical inspection.
Cold wall pattern
may require moisture testing or building inspection.
A good thermal inspection asks:
“What does this pattern tell me to investigate next?”
Thermal Camera + Other Test Instruments
The strongest diagnostic approach often combines thermal imaging with additional measurements.
For electrical maintenance:
Thermal Camera + Clamp Meter + Multimeter
For mechanical maintenance:
Thermal Camera + Vibration Meter + Tachometer
For building inspection:
Thermal Camera + Moisture Meter + Temperature/Humidity Meter
The NF-522 helps locate the suspicious area, while other instruments help confirm the condition.
Practical Electrical Example
Imagine the NF-522 shows one cable termination significantly hotter than neighbouring terminations.
Before concluding that the terminal is faulty, consider:
Are the components carrying similar loads?
Are the surfaces similar?
Could the target be reflective?
Is emissivity appropriate?
Is the viewing angle suitable?
Does a current measurement support the observation?
This produces a more professional diagnosis than relying only on thermal-image colour.
Practical Motor Example
Suppose one bearing area appears hotter than another.
Consider:
Motor load
Bearing type
Operating duration
Ambient temperature
Surface material
Emissivity
Lubrication
Vibration
If both temperature and vibration are abnormal, the evidence for further investigation becomes stronger.
Practical Building Example
Suppose a thermal image shows a cool patch on a ceiling.
Do not immediately conclude:
“Water leak confirmed.”
Instead:
Thermal anomaly detected → check with moisture meter → inspect plumbing/HVAC/roof → determine actual cause
This approach reduces false conclusions.
Noyafa NF-522 Key Thermal Specifications
Important NF-522 specifications include:
Infrared resolution: 200 × 150
Temperature range: -40°C to 330°C
Thermal sensitivity: 65mK
Emissivity adjustment: 0.1–1.0
Frame rate: 9Hz
Display: 2.8-inch TFT
Battery: 5000mAh
Drop resistance: Up to 2 metres
The adjustable emissivity setting is particularly important for users working with different target materials.
How to Get Better Thermal Measurements
For more reliable thermal inspections:
Identify the target material.
Consider the surface finish.
Set suitable emissivity.
Watch for reflections.
Use an appropriate inspection distance.
Consider environmental conditions.
Compare similar components where possible.
Check actual temperature values rather than colours alone.
Confirm suspicious conditions with another test method.
These habits can improve both measurement quality and diagnostic confidence.
Is Emissivity Important for Every NF-522 User?
Yes, particularly if the user wants to interpret actual temperature readings rather than simply locate obvious hot and cold areas.
Understanding emissivity becomes especially important for:
Electrical inspection
Motor maintenance
Industrial machinery
Metallic surfaces
HVAC equipment
Building inspection
Learning this one concept can prevent many common thermal-imaging mistakes.
Looking for a Thermal Imaging Camera in Malaysia?
The Noyafa NF-522 Thermal Imaging Camera provides adjustable emissivity together with 200 × 150 thermal resolution and a wide temperature measurement range for electrical, mechanical, HVAC and building inspection.
MTM Precision supplies thermal imaging and industrial measurement instruments for Malaysian contractors, factories, maintenance teams and engineering companies.
Contact us for NF-522 availability, quotation and application advice.
Contact MTM Precision
MTM Precision Sdn Bhd
No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor, Malaysia.
Website: www.mtmpre.com.my
WhatsApp: +6016-660 7346
Email: mtmpre@yahoo.com
24 Aug 2026
