Microsoft Word - Section 1

Level I Course Manual – Section 1 Publ No 1 560 009 C

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1.Camera Set up and Quick start guide What will you learn • Unpack and setup your equipment • Location of buttons and basic functions • Changing lenses • 3 critical adjustments for success


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A. Uncooled cameras Starting the camera • Install fully charged battery • Attach an optional 12º or 45º lens, if wanted (see page 3) • Insert the PC-card (see page 7) • Put on the head set, if wanted (see page 3) You are now ready to start the camera. Hold the camera in the right palm and adjust the hand strap around the hand until a comfortable position is obtained. Ensure that the buttons are readily operable with your fingers. Press the green On/Off button to start the camera. After approx. 15 seconds an image with an FLIR logo will appear and will be displayed until the camera controls are ready for use.

Release button to open b

Battery eject PC card

On/Off


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Adjust the viewfinder focus to obtain the best display focus for your eyes. Wait until you see an image, point the camera at a warm object to be viewed, like a face or a hand. Button locations and functions

Press the A (Auto) button to automatically get the “best image” in the viewfinder. When this button is pressed an automatic NUC (Non uniformity Corr) is also performed.

Press the S (Store) button briefly to toggle between frozen image and live images. To store the image to the PC-card hold the S button down for more than 1 sec.

The ↵↵↵↵ (Enter) button brings up the menu system of the camera in the viewfinder. Make the selection in the menu by using the joystick control. You accept the menu choice and quit the menu mode by pressing the ↵↵↵↵ button. The ↵↵↵↵ button also means accept or OK.

A ↵↵↵↵ S

Joystick

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Press the A button to activate the auto adjustfunction resulting in a good image in the viewfinder.(See button description sketch below.) Adjust the focus of the camera by pushing thejoystick up to focus further away or down to focuson a closer distance until the sharpest image isreached.

↵↵↵↵

S

A

On/Off


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The C (Clear) button is used when you need to skip a menu selection without making any changes and leave the menu mode. The C button also means escape or NOT OK.

The green ON/OFF button is used to switch the power to the camera on and off. Press the button to switch the camera on. Hold down the button for more than 2 sec. to switch the camera off.

The joystick (button) has various functions. At start up of the camera the joystick is in the default mode controlling focus (up/down) and zoom (left/right). In the menu mode you use the joystick to select the appropriate function and to increase or decrease various parameter settings.

Adding and Changing Lenses The camera is equipped with a built-in 24° lens but an optional 7º, 12º, 45º or 80º lens can also be used. The 7º lens gives maximum magnification (telescope effect). The 80º lens gives maximum field of view (wide angle effect). To add the lens push the lens carefully into the bayonet on the camera, aligning the white dots on the camera bayonet and the lens. Turn the lens clockwise 45° to secure. To release the lens turn it 45° anticlockwise and remove the lens.

C

I

Video 12 V Headset


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The camera recognizes the lens type and applies the correct calibration automatically.

The following table shows the horizontal image size (FOV) at various distances between camera and object for the available standard lenses. The geometrical resolution of the camera is indicated by the IFOV value. Note that the 24° lens is always built into the camera. Object distance

0.3

0.5

2.0

3.0

5.0

10.0

30.0

100.0

(m)

7°°°° Hor FOV IFOV

- -

- -

- -

- -

0.5 1.7

1.2 3.6

3.6 11.3

12.2 38.0

(m) (mm)


- -

- -

0.4* 1.3

0.6 2.0

1.1 3.5

2.1 6.6

6.3 20.0

21.0 66.0

(m) (mm)


- -

0.2* 0.7

0.8 2.6

1.3 4.0

2.1 6.6

4.2 13.0

12.0 40.0

42.0 130.0

(m) (mm)


0.2* 0.8

0.4 1.3

1.7 5.3

2.5 7.8

4.2 13.0

8.3 26.0

25.0 78.0

83.0 260.0

(m) (mm)


0.6 1.8

0.9 2.9

3.4 10.8

5.1 16.0

8.5 26.5

16.952.3

50.4 158.0

169.0 524.0

(m) (mm)

*At close focus

Focus range: 115-150mm 0.1m 2m 0.3m 0.5mHor FOV: 64mm 0.16m 0.42m 0.22m 0.22m

7°

Focus range: 7mHor FOV: 0.4m

64/150close up 80° 12° 45° 24°


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Clear and accurate thermograms require good focusing! In focus Out of focus Accurate temperature measurement needs correct focusing. The applied measurement function shows the highest temperature in the measurement area. The maximum temperature in the correctly focused image is 64ºC whereas incorrect focusing gives a maximum temperature of only 51ºC. The temperature scale is the same in both cases. Remember that you can focus only when you have a live image on the screen. If a stored image is unfocused, you cannot correct it afterwards! Batteries The batteries used in the uncooled camera are of the Nickel-Metal hydride type. One of their big advantages is that they in practice do not develop any ‘memory’. The practical side of that property is that they can be charged at any occasion. You do not have to wait until they are completely discharged. This type of battery, which has been selected for high quality, has proven to be very reliable. On top of that, when the battery is discharged and needs being changed – which will happen after about two hours of operation – it takes only about 40 seconds to have the camera up and running again. And it takes only one hour to recharge the discharged battery! Tutorial: Showing how to operate a few functions The man-machine interface of the uncooled cameras is partly menu-driven and partly using the direct function buttons, described on page 2. Below follows a short tutorial, on how to operate the camera for a few functions. To measure a temperature Press the ↵↵↵↵ button to make the menu system drop down.

20

40

60

20

40

60


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Go to the spot function in the menu tree by pressing the joystick in the desired direction. The spot is located in the Analysis menu. Press the ↵↵↵↵ button when Spot is marked. The spot marker will now appear in the image and the measured temperature will be shown in the upper right corner of the display.

To position the spot, move it with the joystick. When the spot is correctly located press ↵↵↵↵ to go back to the normal function of the joystick (i.e. controlling focus and zoom).


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To save an image Press the A button and focus the image. Press the S button to freeze the image. If the image is OK hold down the S button for 1 second or until the filename (e.g. E123232) of the image appears. These two examples show how simple it is to carry out two very frequently used functions. For a complete overview of available functions, please see the manual. The menu-driven function selector makes it very easy to upgrade the functionality by changing the software. And to take the best of both, the 500 system uses a combination of direct function buttons for the most frequent functions plus easily handled menu-driven function selection. Color palettes There are a number of different color and greyscale palettes. Below you will find examples of most palettes. Judge for yourself, which color/grey scale you find most relevant for looking at this ‘model’ (a cat). Most users find the greyscale best for looking at target geometry, that is, recognising what it is you are looking at.

Continuous greyscale Continuous iron scale Continuous rainbow scale

Medical 10-color scale 10-color rainbow scale Inverted continuous greyscale.


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To each color/greyscale palette some other colors belong. They are:

• Isotherm 1 and/or 2 • Temperature outside span, over or under (saturation) • Temperature outside measurement range, over or under (overrange)

The stove is, as we can see from the temperature scale very hot, up to about 253ºC. However, the red part in the image shows that some temperatures are even higher. This red color is called “over range”. In the image to the right the camera has another measurement range. It can measure temperatures up to at least 500ºC. Therefore the maximum temperature is 304ºC and no saturation. In the first image we get a warning, which tells us that we have not set our camera properly. If we do that we are able to measure the correct temperature.

Inserting the PCMCIA card For thermographic surveys, you want to document your work. Thermograms recorded during a survey are an important part of documentation and reporting. The thermograms have been stored on a storage medium, called a PCMCIA card. Depending on the size of that card – and that size is increasing all the time – you can store thousands of images. Today, May 1999, the usual size is 540 Mbytes, which corresponds to some 3000 images. A PCMCIA card is in all essentials a small-sized hard disk, which is inserted into the PCMCIA slot on the backside of the camera. Insert the PCMCIA card with its upper side

facing left, as shown in the photo on the left.When pushing it into its slot, be careful not todamage it should you, by mistake, have put itin the wrong way.

100

200


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Measurement modes • Auto adjust • Spot • Area • Profile • Isotherm • Delta Not all measurement functions are available in all camera types. They work on live as well as stored and recalled images. The auto adjust function, which is activated by the A button, finds the hottest and coldest points in the scene and adapts the temperature scale to it. However, this works in a slightly modified way, as some of the hottest and coldest points are rejected before adaptation. The spot function reads the temperature of the one single pixel inside the cross hair. It can be set to automatically find the hottest or coldest point inside a box, or it can be set to be moved around the image by means of the joystick. The area, which is a box or a circle, can display the maximum, minimum or average temperature inside the area. The area is always centred in the middle of the image, but its size can be changed by means of the joystick. The profile places a horizontal or vertical line over the image and displays the corresponding thermal profile at the bottom (horizontal) or to the left (vertical) in the image. There is a cross hair on the line, which shows the temperature in that point of the line. The joystick moves the cross hair along the line. The isotherm is used to highlight in colors, which vary with the selected color or b/w scale, all temperatures above, below or inside a selectable temperature interval. The delta mode will show a temperature difference between the spotmeter temperature and a pre-selected temperature value.


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Internal components Although the uncooled ThermaCAM cameras do have uncooled detectors, the electronics inside the camera generate heat, which is conducted to the aluminium case. The camera will therefore feel warm. The picture below shows the principal build-up of the camera. The ‘heart’ of the camera, i.e. detector, lenses and filter and focusing mechanisms are surrounded by electronics.

Uncooled detector

Lenses (Germanium)

Shutter actuator


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Menu tree The menu system is built up around four main categories in the menu system. These main categories are: File, Analysis, Image and Setup. Each category has a submenu. All submenus, which finish in dots (…) have submenus in their turn. In order just to look at an example, let us select Manual adjust from the Image menu.

This is the ‘final’ submenu, and it is shown at the bottom of the image. This is the text in the operating manual: Level: Sets the midpoint of the temperature span displayed in the image Span: Sets the span of the temperatures displayed in the image Temp range: The standard camera supports two different temperature ranges.

If a high temperature option is installed, you will get an extra range.

Remember, values are changed by pushing the joystick up or down. You go from one submenu to the other by pushing the joystick left or right. A function is started (‘executed’) by pressing the ↵↵↵↵ button. (At the top or bottom of a menu, continuing to push the joystick will let you jump to the first selection.)


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True temperature measurement Most certainly you want a decent accuracy on your measurement results. There is a category in the menu tree, called Object parameters, where you should set some values, which are absolutely crucial for obtaining good, trustworthy, ‘true’, temperatures. Emissivity setting Set the emissivity to the value that is valid for the object you are measuring. Setting the Distance and Relative Humidity The infrared radiation from the object, which we measure to calculate the temperature of that object, is attenuated by the atmosphere through which it travels. The influence on the measurement result of that attenuation is automatically compensated for, provided you enter the distance from the camera to the object and the relative humidity of the atmosphere. Atmospheric moisture is the primary atmospheric attenuator for long wave IR cameras. Setting the Tamb, i.e. the background (ambient) temperature The background temperature is the temperature you would measure if the target were a perfect reflector (heat mirror), provided the emissivity is set = 1.0. You cannot do this simply. There are methods to get a good estimate of background temperature. They will be covered later in the training course. Put that value into the Object Parameter list. Now you are prepared for getting correct temperature measurement values. Do!


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B. Cooled Cameras 1. Attach Battery 2. Power up camera 3. Point at target 4. Auto-Span With the power switch in the off position, attach the battery or AC power supply to the back of the camera. If you are using an external monitor or video recording device, attach the video output of the camera to the video input of the device. If you are using ThermaGRAM, or recording video with the intention of analyzing the videotape with ThermaGRAM, you must connect the TGRAM output of the camera to your ThermaGRAM board or video recorder. (If you have an SC-1000, you have an additional option. You may connect the 12-bit digital output to your ThermaGRAM card or to the ThermaCAM Researcher.) When all connections are secure, turn the power on. The miniature closed cycle stirling cooler will operate and cool the focal plane array down to a temperature of 77 Kelvin (-321°F, -196°C ). This will take about 7 minutes. Once the FPA is cooled, the cooler will throttle back and operate slower. Look through the viewfinder and adjust the focus of the viewfinder using the slider located on the bottom. You do not need to have an image; you may focus on the text. Do this even if you have an additional external monitor. Point the camera at your target of interest and push the Auto-Span button. This will adjust the Level and Span (brightness and contrast). If you are not satisfied with the appearance of the image you may try adjusting the Span and Center Temperature by using the buttons on the top of the camera.


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5. Focus 6. Measure target temp 7. Range verify correct 8. Save image Get close to your target, if possible. If the target looks too small, use a telescope (a lens with a smaller field of view). Try to make your target of interest fill the field of view. If your target appears too small, this may result in temperature measurement errors. Focus the image by rotating the lens, just like a 35mm camera. Focus is essential for good temperature measurements; don’t rush! If you capture an image that is not in focus, you will not be able to focus it using post image processing. Use the spot tool, which is accessed by pressing the mode button, and measure the temperature of the hottest spot on the target that you want to measure. Take advantage of the Freeze button. Freeze the image; and, with the use of the soft set or arrow buttons, move the spot around the image to locate and measure the hottest spot that you are interested in measuring. If the temperature reads “OVER,” you must change to range 2 by using the range button. Unfreeze the image and change to range 2 if needed. Repeat this procedure, if necessary, until you can get a temperature reading. Once the range is correctly set, save an image to your PCMCIA card. The Freeze/Save switch must be set in the Save position. When you hit the button once it will freeze the image and show the location where it is going to be saved. Hitting the button a second time will save the image to the PCMCIA card. The 12-bit TIF image will occupy 123 KB of space. Viewfinder & Monitor Normally the viewfinder will stay attached to the camera while it is in the case. If you have an older system, the case may be smaller and the viewfinder is removed from the camera when storing. The viewfinder can slide back and forth and once set in the preferred position it will lock in place. It will also tilt up and down. It is recommended to leave the viewfinder in the down position so that the view you see corresponds to where you are aiming the camera. If dust gets inside the viewfinder and is seen on the screen, you may remove the eyepiece of the viewfinder to gain access to the interior. Use an air bulb or compressed dry gas for cleaning optics to remove the dust.


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When using the viewfinder outdoors in sunlight, be careful to prevent the direct rays of the sun from entering the eyepiece. The lens on the viewfinder can focus the sunlight onto the video display inside and cause damage. If you have a situation where you have to wear a full face shield, or you need to observe objects that are very low to the ground or above your head, the LCD monitor is preferred. It is also more convenient if more than one person needs to view the image. Power Source / Cable Connections The small video outputs on the left and right sides of the ThermaCAM (Video and TGRAM) are MCX connections. If you would like to attach a BNC connector to either of these outputs you will need an adapter ( BNC/F to MCX/M ). The Video output will display the same image that is seen on the viewfinder. It may be attached to any device that accepts an standard video signal. This includes monitors, VCRs, video printers, LCD video projectors, frame grabbers, etc. The TGRAM output will display the image in grayscale with all of the text and temperature measurement tools removed. If you are going to use the ThermaGRAM image processing system to analyze real time video images — either directly, or from images recorded on videotape — this is the video source that you should use. One exception to this is the model SC1000. With this unit you can use the digital video output as a source. With digital video the signal will be 12 bits, with analogy it will be 8 bits. If you are using the TGRAM video output, do not use a splitter or connect the signal to a time-date generator or similar equipment. This will corrupt the data. You may connect both the video and TGRAM output signals to different devices at the same time. The S-Video output is the same signal as the viewfinder. It is intended for monitors and other devices that accept S-video signals. The Remote I/O connector is used to download new operating software, or to allow remote operation with a PC or remote panel.


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Power Modes On/Standby/Off/Playback In the off mode, all power is off. However, it is recommended that you do not leave the battery attached to the camera. In the standby mode, the cooler is on. The electronics, including the video output, are off. This allows you to conserve battery power. If you operating on battery power and have to travel between inspections you have three choices: 1) Keep the camera running. If you are travelling only a short distance, which takes only a few minutes, this is recommended. 2) Turn the camera completely off. If you will not be using the camera for an extended period of time, this is probably your best choice. 3) Use the standby mode. If it takes you twenty minutes or so to travel to your next destination, it will be more convenient to wait one minute for initialization, rather than seven minutes for cooldown. Cooling down consumes more power than normal operation or standby. In the playback mode, the cooler is off. The video, including the ability to recall images from the PCMCIA card, is enabled. This allows you to review the images that you have captured using minimum power. Cooled Cameras X90 Series Standby - Cooler is on electronics are off saves battery life Playback - Video is on cooler is off allows you to review images with minimum power How to Properly Hold your ThermaCAM Right hand is through the strap for safety, and to reach the span and center keys. Left hand is on the lens for focusing, and to reach other buttons When using LCD monitor it may be more comfortable to hold down at your waist. The fingers of your right hand can operate the Span and Center keys located on the top of the camera.


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Your right thumb can operate the Save/Freeze switch and pushbutton located on the right side of the camera. With your left hand you can focus the camera and also operate the main keypad. The keys are set up for tactile operation. With experience you should be able to locate all of the keys without looking at them. Button Locations and Functions Your camera is an expensive sophisticated electronic / optical instrument. Familiarize yourself with all of the controls, features, buttons, menu items, etc. Time invested in learning how to operate your instrument properly will pay off in the future. Adding or Changing Lenses X90 Series To remove lens: Set Switch in down position. Push button in and turn lens counter-clockwise To Add Lens: Lock lens (switch in up/lock position.) Match white dots and rotate lens into place. Slowly rotate the ring nearest the camera body to seat the lens and the thermistors. It will click when properly seated. Unlock lever for manual focus The ThermaCAM standard lens provides a 17° horizontal by 16° vertical field of view. For small, distant targets, such as connections or switches on transmission lines, it may be necessary to use an infrared telescope. This is a lens with a smaller field of view. An 8° lens (2X telescope) or a 4° lens (4X telescope) are available options. Using the Zoom key will magnify the image, but it will not increase the spatial resolution of the camera. If your target is too small to measure, you must get closer to it or use a telescopic lens. In some cases, you may need to do both. Sometimes your target is too large, and will not fit into the field of view using a standard lens. Buildings, kilns, and motor control center “buckets” are examples of targets that appear too large because of physical size, or simply because you cannot get far enough away from them in their environment. Here you have the option of using a wide angle lens. This is a lens that decreases the magnification and increases the field of view. This would be a 32° lens (.5X telescope).


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Infrared lenses are expensive items. Treat them with care when changing and storing them. Use lens caps and cases provided. It is necessary to remove the lens when installing or removing filters. Clear and Accurate Thermographs require good focusing! Out of focus images yield inaccurate temperature readings In spot mode, adjust focus to get the highest temp for good focus Focus, focus, focus. Be sure that your viewfinder is in focus for your eyes before you try to focus the camera. If someone else was using the camera they may have adjusted the focus in the viewfinder. If you cannot see clearly in the viewfinder you will not be able to tell if the camera is in focus. If you move closer or further away from your target be sure to re-focus. When observing small targets, using the zoom feature can magnify the image and help you see if you are in focus. If you are looking at a target that has very few discernable features on it, such as a wall or the side of a large transformer, place an object on the surface as a reference to focus on. A pen or a coin will do nicely. Remember, you cannot readjust focusing on a stored image buy using the camera or post image processing. You have to live with the results, so make it good the first time. Carpenters say “measure twice, cut once,” thermographers should say “focus twice, capture once.” Identify Your Components Accessories: Know yours Lenses, filters, monitors, screen shades,VCRs, remote panels, carts, tripods, adapters, disks, heat shields, protective windows (spark shields), PCMCIA cards, cables, visual (film) cameras, digital cameras, video printers, computers,


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Battery optimization NiCad batteries can develop a “memory.” Be sure that you have the means to discharge and recharge (recycle) your batteries on occasion. Use the identifier switch on your battery as you wish to designate if it is charged or not. Many of the accessory items that are used with thermal imaging systems are compatible with other video products. Monitors, VCR,s and batteries are just a few examples. You should know exactly what you have for accessories and see to it that these items are labelled or identified as belonging to the infrared camera. If you are not using these accessories, keep them in a safe place. Know the waveband, temperature ranges, filters, lenses, recording capability, temperature measurement modes and post-image processing capabilities that you have available to you. If someone asks you to use your equipment for a particular application, you should know beforehand if you have the right equipment available for the task ThermaGRAM Calibration Disk Only needed with ThermaGRAM software Calibration tables for that camera Keep for future use The ThermaGRAM calibration disk is shipped with every system. It is updated if your system is returned for general maintenance and / or recalibration. You will not require this disk unless you have ThermaGRAM image processing software. ThermaGRAM is a software package that requires the installation of a full-length card in a desktop PC or docking station. In general, ThermaGRAM is used by people that need to do real-time analysis of images; where still images will not provide the information that they require. This usually involves R&D, scientific or medical applications, etc. Most Predictive Maintenance applications do not require ThermaGRAM. If you have TherMonitor image processing, you do not need to install the ThermaGRAM calibration files.


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Main Menu: Functions Mode Recall Zoom Setup Range Recall B&W Color Auto Span Emissivity Pressing the Mode key will sequentially step you through all of the presentation or temperature measurement modes available with your camera. Modes can be changed on stored images. Pressing the Setup key will bring up, in sequence, a series of menus from which you can enter environmental conditions and operator preferences.. Press the Mode key to return back to normal operation. The Recall key allows you to view and recall the images that are stored on the PCMCIA card. The Auto Span key adjusts the center temperature and span for optimum values. The auto span key will work on stored images. The Aux key enables the auxiliary function that has been selected in the setup menu. (Auto Range, Reticle, Palette, Ext Nuc, None.) The Zoom key operates the electronic, or digital zoom. Pressing once will yield a 2X zoom; twice, a 4X zoom; a third time will return to 1X. The Zoom function will work on stored images. The Range key will sequentially step through the spread of temperatures, or temperature ranges available. This may be restricted by preferences set in the setup menu. Ranges cannot be changed on stored images The B&W Color key will toggle between grayscale and color image. (If the color palette is to #0, or 256 shade grey, the change will not be apparent.) The Emissivity key will adjust the emissivity of the image from 0.1 to 1.0. Emissivity may be adjusted on stored image Color Palettes Color Vs Black and White Black and white provides the best resolution, recommended for scanning and focusing Color is recommended for very large smooth surfaces to detect subtle temperature changes


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Color can be applied to the live images, stored images or by using post image processing Images stored on the PCMCIA card are saved in grayscale, even if the viewfinder displays color. The application of color to a thermal image is a subjective choice. The human eye is quite sensitive to color. By applying a false color scale to the grayscale image you can effectively increase your sensitivity to apparent temperature variations. There are many color palettes to choose from: 1. 10-color rainbow 2. 20-color rainbow 3. 256-color rainbow 4. 256-color inverted rainbow (yellow and red colors are reversed) 5. 256-color iron bow 6. 256-color glow bow 7. 10-color contour 8. 10-color medical 9. Saturation / thresholding (gray scale with red=hot, blue=cold) Do not concern yourself with color palettes until you are ready to print an image or display it by other means (videotape, viewgraph, presentation). When scanning, the saturation palette is recommended. If you use a palette with only 10 or 20 colors, you will actually lose detail in the image. Saturation Palette Provides the best of both worlds: black and white with selected colorization Temperatures above a selected temperature will be red, those below a selected temperature will be blue Good for repetitive analysis Essential for 8-bit video ThermaGRAM The saturation palette is unique. It is essentially a grayscale image with the very high end of the scale colorized in red (hot) and the very low end colorized in blue (cold). The upper and lower theresholds can be set when using the saturation palette. For example, if you set the high end to 100°F and the low end to 50°F, any object with an apparent temperature of 100°F or greater will be colored red and any object with an apparent temperature of 50°F or less will be colored blue. This allows you to find your “hot spots” while viewing the image in a high resolution grayscale mode.


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Attention: ThermaGRAM users: Keep in mind that in any colorization scheme, the displayed video is what is being colorized. You may save 12 bit digital images on your PCMCIA card and analyze them with ThermaGRAM as long as the objects that you wish to measure fall within the camera’s range when the image was taken. The video signal, however, is not 12 bits but 8 bits. This means that the image from your video cable, must be set to a span to cover the temperatures that you wish to measure. This is easily accomplished by using the saturation palette. Adjust the span and center temp key to remove all red or blue colors from the objects you wish to measure. Now when you send this signal to your ThermaGRAM card you will be able to collect temperature data from the video. Cursor or Function Keys The cursor keys, function keys, or arrow keys, as they are sometimes called, will change their function depending on the mode selected. In the image mode the forward and backward arrows will change the color palette. In the spot mode, the keys will move the spot around the image. In the auto spot mode the keys will position the temperature box. If the aux key is pressed, the forward and backward keys will adjust the height of the box; the left and right keys will adjust the width of the box. In the delta mode, the keys will move the second reference spot around the image. In the graph mode the forward and backward keys will move the vertical crosshair in order to show the spot temperature.The left and right keys will move the horizontal line marker selecting the trace. In the isotherm mode the forward and backward keys will set the isotherm temperature. The left and right keys will set the isotherm width. In the setup mode the forward and backward keys will select menu items and the left and right keys will change parameters. In the recall mode the keys will allow you to browse through the thumbnail images. Center and Span Keys The center key moves the displayed temperature span up or down the current temperature range. For example, if your camera is set at a span from 30°F to 110°F, your span is 80°F. If you press the + side of the center key your span will stay at 80°, but it will shift towards higher temperatures, such as 40°F to 120°F. In visual terms, you may think of this as a “brightness” control. If you prefer electronic terminology, it is an “offset” adjustment.


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The span key adjusts the width of the temperature span around the center temperature. If your span is set from 30°F to 110°F, your span is 80°F, and your center temperature is 70°F. If you press the + side of the span key your overall span will increase, such as 20°F to 120°F, which is a span of 100°F. The center temperature, however, stays the same at 70°F. In visual terms, you may think of this as a “contrast” control. For the electronically inclined, it is a gain adjustment. Temperature Span Control Temperature span like “Thermal Contrast” Expands or contracts visible temperature span Similar to contrast control on TV Center Temperature Control Center Temperature like “Thermal Brightness” Moves temperature span up and down temperature scale Similar to brightness control on TV Inserting the PCMCIA Card PCMCIA What does it stand for? Personal Computer Memory Card International Association (Or, if you prefer: People Can’t Memorize Computer Industry Acronyms) PCMCIA cards are essentially storage devices, like floppy disks, hard drives, Zip disks, etc. They must be formatted; they can be erased and they can save all kinds of files. The ThermaCAM can format your PCMCIA card, store and recall images, and write over images on the card. The card can store all kinds of files, but the ThermaCAM will only recall the grayscale TIFF images it has stored. If unwanted files are copied to your card, when you insert the card in your camera you could get a message stating that the card is full. If you were to examine the thumbnails, it would appear that there is more space available to store images. If you were to place your card in your PC, open ThermaGRAM or TherMonitor to analyze the images, and then save the images, unless you specify a new directory, the images will be saved on your card. The images will have a new file extension (TGW, or TMW). The ThermaCAM cannot read these files. To prevent this from happening, after you capture your thermal images on your card, copy them to a selected folder on your PC and remove the card from your PC. Always use the camera to format your card.


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Store/Freeze Button: (Located by right thumb) Freeze - allows you to freeze and unfreeze images Store - allows to freeze and select the storage location. Pushing again allows you to store image to card. Button must be pushed twice to store! A frozen image can be stored by changing the switch position to save and pressing the button. If you press the button intending to freeze the image but you are in the save mode, you can change the switch to the freeze position and simply press the button again. If you accidentally save an image that you do not want you can copy over that image by selecting that location for the next image you wish to save. Let’s say that you have pressed the button twice while in the save mode and saved an image to A05. When you prepare to save your next image it will be assigned A06. Simply reassign the allocation to A05, using the arrow keys, and your new image will write over the one in A05. A message on the display will ask for confirmation so you do not accidentally erase images that you wish to keep. If you have the Autosave feature enabled, when you press the save button your camera will save a predefined sequence of images. If this option is available with your camera you can confirm the setting by checking your setup menu. Narcissus & Reflections A reflection of the detector or focal Plane Array off the target or window through which the camera is viewing Most important when working around IR reflective surfaces, and cover plates. To check for this move the camera at an angle. Narcissus will move with the camera. The closer you are to the target the more likely you are to see this. Narcissus, from Greek Mythology, was the youth who fell in love with the reflection of his own image in a pool and, pining away, eventually died. If you are looking perpendicular to a flat smooth surface, the camera will, to a certain extent, be looking at a mirror. The camera will “see” it’s own thermal image. The apparent cold spot in the center of the image is the cold detector element being reflected.


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When looking through an infrared window, such as germanium, sapphire, or zinc selenide, narcissus can also be observed. Although these materials have a very high transmissivity, there is still a small percentage of thermal radiation being reflected back to the camera. If you look at a piece of glass you can see your own reflection in visible light, yet you can rest assured that most of the visible light is passing right through the glass, and very little is being reflected. Ignoring narcissus can lead to temperature measurement errors. Measurement In the auto mode the hottest or coldest spot can be located; or, the average temperature within a defined box or the whole image can be determined. In the spot mode, the temperature of a spot can be read. The spot may be a single pixel, a 3 X 3 array of pixels, or a 5 X 5 array of pixels. The arrow keys may be used to move the measurement spot around the image. In the peak mode, the temperature displayed will represent the highest temperature that the spot has come across. This can be used with a live image, or one that has been recalled. In the delta mode, the temperature difference between two spots will be displayed. With the static option, the first reference point is held in memory and will not move. This would give the operator the ability to take a reference of one target and get a delta measurement of another target that is not in the field of view. With the dynamic option, the first reference point will move as well as the second reference point. The profile mode, or graph mode, places a horizontal line on the image and displays a thermal profile of that line on the bottom of the image. A crosshair on the graph shows the temperature at that point on the line. The isotherm mode is used to selectively highlight, in white, black or red, all points in the image with the same temperature, or sub-range of temperatures. Isobars identify lines of equal barometric pressure in meteorology, isotherms identify lines of equal apparent temperature in thermography. The red isotherm can only be seen in the color mode.


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Cooler and Detector The Stirling Closed Cycle Microcooler is basically a compression expansion refrigerator without valves. The cold finger - where the detector or focal plane array is mounted - is chilled to a temperature of 77 Kelvins (-321°F). Sensors provide feedback to regulate and maintain the temperature. The detector assembly is enclosed in a high vacuum to provide thermal insulation. Should a problem arise with cooler operation, a message will appear on the viewfinder. Cooling the detector or focal plane array increases the thermal sensitivity of the camera. As an analogy, consider stargazers. Where do they go to view dim stars? Often they will travel away from the city lights. Infrared sensors detect “infrared light” or thermal radiation. To make them more sensitive you place them in an environment with very little thermal radiation, someplace very cold. Internal Components Any heat generated by internal components is conducted to the aluminium case, keeping the interior of the camera cool. This is why the body of the camera may feel warm to the touch. This efficient thermal management system works so well that there is no need for a cooling fan, which would consume a considerable amount of power, and subject sensitive internal components to environmental airflow. Hardware Designs: Components The IR FPA needs to be cooled to improve the image quality (less “snow” on image). Low weight, low wattage coolers are expensive to make. Since, IR does not pass through glass well optics for IR are made from IR transparent materials: PtSi,Ge. The electronics and power components allow coordination of detectors of the FPA (or high speed mechanical parts for a scanning camera) to get a uniform image.


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Setup Menu pages 1-5 The setup key calls up 5 main menus with the following Parameters: Menu 1: Background Temp Ext. Optics Trans (%) Distance (meters) Ext. Optics Temp Relative Humidity (%) Secondary Lens Trans (%) Atmospheric Temp Alowed Temp Rang Menu 2: Keypac Response Recall Configuraiton Polarity Save Configuration TIFF Format Format Storage Device Keypad Backlighting Modify Date – Time Menu 3: Color Palette Display Reticle Temperature Units Display Logo Remote Temperature Out Application Code Re. Cursor Size Menu 4: AUX key function Status Box Update Rate Profile Mode Background Condition RED Delta-T Ref Sampling Set up Autosave Isotherm Color Clear All NUC Tables Menu 5: Auto Temperature Mode Barcode State Save Screen Snapshot FPGA Code Rev.

Level I Course Manual – Section 1 Publ No 1 560 009 A

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Apparent Temperatures Vs. True Temperature How much accuracy do you need? Throughout this course you will learn many ways to compensate for the various environmental and target factors that exist in the field. Some of these factors cause dramatic temperature variances and some cause minor changes Apparent Temperatures Temperature readings without correction through the camera or software for emissivity, background, distance, humidity, external optics factors etc... Assumes target is a blackbody (perfect emitter) Real or true temperature readings are corrected for emissivity, background, etc. Setting Emissivity and Background Set the emittance to 1 Measure your background temperature (Foil) Set the emissivity to determined value Measure temperature Setting the Distance and Humidity Estimate distance and enter in Setup Menu Estimate humidity and enter in Setup Menu Effect on Temperature Measurement Accuracy Emissivity Background External Optics Transmission Atmospheric Settings External NUC Function: TCAM 50-80 series Directions: In Set-up menu 4 set the Aux key function to NUC Put the lens cap on the camera Press the AUX key In 30 seconds the new calculations are done Go back to Set-up and reassign the AUX key to avoid accidental NUC’s without a lens-cap. NOTE: If you accidentally NUC without the lens-cap one, you will see a clear ghost image. Re-NUC to fix.

Level I Course Manual – Section 1 Publ No 1 560 009 A

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Conclusion: Methodical Thermography Inspect the target visually Auto-span Focus Distance Temp. Range Compensate if needed Store Report Consult with other sources if necessary Follow up

Three critical adjustments • Camera Focus • Temperature Range • Operating Distance Errors in any one of the above will result in improper temperature or temperature difference measurements. Cannot be changed in image post-processing. Focus

• Out-of focus dilutes temperature rise. • The smaller the target, the worse the effect.

Temperature Range

• Out of range data cannot be recovered. • 12-bit systems with 8-bit displays give a factor of 16 cushions.

Operating Distance

• Too great a distance from a hot target causes low readings. • Knowing your camera’s spot size ratio is important. • Top, standard optics. Bottom, 8 degree lens.

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