|What camera(s) are your customers using as a basis of comparison?
I think what they may be referring to is the thermal noise of your camera.
Medical thermograms are usually taken using a lower center temperature level and smaller temperature span than most industrial thermography. Because of this, thermal noise (thermal sensitivity) is more apparent.
The palettes that are typically used for medical thermography (rainbow) also tend to accentuate this. Try applying an Ironbow palette and a rainbow HC palette to the same thermogram, you will see what I mean.
If your camera has any noise reduction, or sensitivity improvement options (e.g. image averaging), it would be wise to turn them on. Also, if you can, enlarge the temperature span as large as practicable (making sure you can still find the anomalies you are looking for!).
To be sure, there are cameras on the market with better sensitivity and greater spatial resolution, but most users of FLIR P or S series cameras seem quite happy with the quality of their images. And many veterinary thermographers are getting great results with an E series instrument.
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