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| Pixel resolution |
The first consideration is the number of pixels. Today there are three
standard resolution (camera several manufacturers' deviate slightly)
• Low Resolution - 160x120 (19,600 pixels)
• Medium Resolution - 320x240 (76,800 pixels)
• High Resolution - 640x480 (307,200 pixels)
• Medium Resolution - 320x240 (76,800 pixels)
• High Resolution - 640x480 (307,200 pixels)
How
much resolution you need (verse want) is primarily determined by your
application and to the value you provide to the quality of the image.
When evaluating a digital camera with a 5 paragraph 10 mega pixel most
users will not benefit by buying a camera with 10 million pixels because
they are never going to print images on paper that is large enough
where the resolution will provide better print quality. While you will
always print out and display the full resolution of an infrared camera
from the highest resolution available is relatively simple with today's
digital camera standards. Even at a resolution of 640x480 pixels high
definition thermal image will only take a fraction of today's computer
displays and thermal print image quality produced will always be fully
realized. Therefore when evaluating a thermal camera the number of
pixels that are relevant and enhance the resolution is the most
significant consideration in improving image quality.
Another benefit to high resolution is the ability to zoom into the scene and maintain good image quality. The majority of the thermal camera with a standard optical features horizontal field of view around 25 °. Apart from the resolution of 640x480 pixel camera performance is set to 2X digital zoom will match the performance of the camera with a resolution of 320x240 with ° (and often expensive) optional 12 (2X) lens. If you anticipate the need for imaging objects at a distance of more than 20 feet you should consider the incremental cost 2X 320x240 thermal lens to the camera when comparing the total cost of between 320x240 and 640x480 system.
The second major problem that impacts the image quality of thermal sensitivity. Although there are several tests used to measure this specification, thermal sensitivity basically defines how well the camera would image that you increase the contrast of the image. Thermal sensitivity varies with the temperature of the object, with increasing temperature the slope of the object detector output signal increases with increasing temperature. This means that the signal (increase) to noise (fixed) to increase the ratio when you see a hot object. But this does not usually benefit because applications where better thermal sensitivity can be utilized is a low temperature (room temperature) applications where the thermal contrast (temperature delta in the picture) is very low. Low Typical applications include building diagnostics of thermal contrast in which the interior wall imaging camera with a very slight variations in temperature or emissivity differences and issues such as moisture or insulation quality can only be visualized with increased contrast sensitivity to the point where the useful temperature limit of thermal cameras span settings .
When you review the published specifications of the camera you'll see the specification of thermal sensitivity range between 0.25 ° C (250mK) and 0.05 ° C (50mK). While you may consider one-fourth degree is a sufficient thermal sensitivity as soon as you see low contrast scenes you'll find the ill effects of image quality image quality as the noise began to dominate the picture.
thermal imaging usually display images in the color palette consists of 256 liver or gray level. Imagine your target has a temperature difference between 0 ° C and 256 ° C of each level of gray or color will represent 1 degree difference in temperature. Now apply the same color mapping into a scene with a temperature between 25 ° C and 35 ° C or 10 degrees. Every color now represents 0.03 ° C (10 ° C ÷ 256), the value is lower than the most sensitive uncooled camera. The result is that some of view of noise. There are many applications that are very important to set the range as narrow as possible to see the smallest temperature variations are possible. If you use a camera with a sensitivity of 0.25 ° C and want to maintain the same level of noise you have to set the temperature between 65 ° C (150 ° F) which is likely to generate image contrast is very low. You must realize that the difference between a camera with 50mK sensitivity camera with a sensitivity clause 100mK is 100% better and not as 0.05 ° C better.
Another benefit to high resolution is the ability to zoom into the scene and maintain good image quality. The majority of the thermal camera with a standard optical features horizontal field of view around 25 °. Apart from the resolution of 640x480 pixel camera performance is set to 2X digital zoom will match the performance of the camera with a resolution of 320x240 with ° (and often expensive) optional 12 (2X) lens. If you anticipate the need for imaging objects at a distance of more than 20 feet you should consider the incremental cost 2X 320x240 thermal lens to the camera when comparing the total cost of between 320x240 and 640x480 system.
The second major problem that impacts the image quality of thermal sensitivity. Although there are several tests used to measure this specification, thermal sensitivity basically defines how well the camera would image that you increase the contrast of the image. Thermal sensitivity varies with the temperature of the object, with increasing temperature the slope of the object detector output signal increases with increasing temperature. This means that the signal (increase) to noise (fixed) to increase the ratio when you see a hot object. But this does not usually benefit because applications where better thermal sensitivity can be utilized is a low temperature (room temperature) applications where the thermal contrast (temperature delta in the picture) is very low. Low Typical applications include building diagnostics of thermal contrast in which the interior wall imaging camera with a very slight variations in temperature or emissivity differences and issues such as moisture or insulation quality can only be visualized with increased contrast sensitivity to the point where the useful temperature limit of thermal cameras span settings .
When you review the published specifications of the camera you'll see the specification of thermal sensitivity range between 0.25 ° C (250mK) and 0.05 ° C (50mK). While you may consider one-fourth degree is a sufficient thermal sensitivity as soon as you see low contrast scenes you'll find the ill effects of image quality image quality as the noise began to dominate the picture.
thermal imaging usually display images in the color palette consists of 256 liver or gray level. Imagine your target has a temperature difference between 0 ° C and 256 ° C of each level of gray or color will represent 1 degree difference in temperature. Now apply the same color mapping into a scene with a temperature between 25 ° C and 35 ° C or 10 degrees. Every color now represents 0.03 ° C (10 ° C ÷ 256), the value is lower than the most sensitive uncooled camera. The result is that some of view of noise. There are many applications that are very important to set the range as narrow as possible to see the smallest temperature variations are possible. If you use a camera with a sensitivity of 0.25 ° C and want to maintain the same level of noise you have to set the temperature between 65 ° C (150 ° F) which is likely to generate image contrast is very low. You must realize that the difference between a camera with 50mK sensitivity camera with a sensitivity clause 100mK is 100% better and not as 0.05 ° C better.
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