Configure Input > Display
The Configure Input > Displaytab provides you with a number of possibilities for op- timizing the way live-images and snapshots are displayed on your screen. These in- clude:
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having an overexposure warning appear;•
enhanced-contrast onscreen display of images even if acquisition conditions are poor, via automatic or fixed-scale contrast enhancement (Automatic gain display or Fixed scaling),•
checking on current intensity distribution (intensity = mean of all 3 color chan- nels) during image acquisition using the online histogram;•
activating live overlay;•
setting the scaling of an image within its viewport.N e w Chan nel Con figure Input > Inpu t
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Live overlay If the Live overlay check box has been selected, image overlays are also available to you in the live acquisition mode. This means you may:
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conduct numerous measurements within a live-image as well and have the re- sults written in the overlay;•
have a measurement grid and automatic scale bar shown within the live image;•
during the live acquisition, already highlight and label image details (or more generally, write texts or insert graphics into the overlay).Please note: The following functions for Olympus Soft Imaging Solutions cameras are available only if the Live-Overlay has been activated: setting the ROI for white balance in the live-image, Partial Readout, and setting the ROI for a sharpness monitor in the live-image.
Automatic gain display
Use the automatic gain display to acquire images independent of the illumination pa- rameters. The system analyze the current histogram in real time and spreads the his- togram onto the entire dynamic range of the camera.
Even when working with the automatic gain display, you should align the exposure time with the actual illumination parameters. Use the online histogram as a check. The exposure time should be set in such a way, so that the spread of the histogram is as wide as possible, thus filling the entire dynamic range.
Please note: The automatic gain display only slightly improves the image contrasts. Over exposure cannot be corrected by the Automatic Gain DisplayInversely, there is increased noise if the image is very much underexposed.
You cannot use the Automatic Gain Display if you want to compare the intensities of numerous images with one another.
Acquiring images
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This online histogram shows a narrow distribu- tion. The image would thus be dark and lacking contrast without auto- matic gain display. When the Automatic Gain Display has been activated, the existing signal range will be spread to improve mon- itor display. This makes image structures much more clearly visible.
Online histogram If the Online-Histogram check box has been selected, you can check the intensity distribution during image acquisition. During image acquisition, a window showing the current histogram will appear automatically. This histogram will be continually up- dated.
The histogram shows you if the image is illumi- nated properly. The dis- tribution is cut-off to the right if the image is over- exposed. If the image is underexposed, the dis- tribution shows a peak at the left.
Image scaling Your image analysis program offers you several possibilities to customize the size of the image to fit the active viewport. The view of the image in the viewport does not have any effect on the actual image resolution.
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Underscan: the system automatically selects from the zoom factors (of 25%, 50%, 100%) the one at which the entire image is displayed within the viewport. This may mean that some viewport space is left over.•
Overscan: the system automatically selects from the zoom factors (of 25%, 50%, 100%) the lowest zoom factor at which the complete viewport is taken up by the image. In certain cases, the image will not be visible in its entirety.•
Adjust to viewport: image size is adjusted to fit the viewport’s current size. In some cases, stripes can appear in the live-image display. Should this be the case, use either the Underscan scaling or the Overscan scaling.•
Full size (100%): the live-image will be shown with no zoom factor. If the view- port is smaller than the image, only as much of the image as fits within the view- port will be shown.Acquiring images Optimizing display - Step-by-step
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Depending on the im- age scaling selected, the image will appear in different sizes in the viewport.
Step-by-step
Optimize live display
1) Select the Image > Configure Input... command (or click on the Configure Input
button in the Set Input dialog box).
2) Select the Display tab.
3) Select the Display warning check box in the Over exposure group.
4) Enter 0.5 into the Overflow field.
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The program will then caution you, "Warning! Over exposure!" as soon as more than 0,5% of the image's pixels are white, during an acquisition.5) Select the Activate check box in the Automatic gain display group.
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Now the image will always be shown with enhanced contrast onscreen no matter what the actual illumination conditions are. Please note that over- exposure and/or over illumination cannot be corrected by the automatic gain display.6) Enter the value 0.01 in the Right overflow field.
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Now 0.01% of the brightest image pixels will be displayed white onscreen.•
Use the right overflow value to prevent pixels which are too bright from in- terfering with the automatic gain display.•
A Left overflow value cannot be defined for the ColorViewIIIu.7) Select the Online Histogram check box to check the actual intensity distribution during a live image acquisition and to appropriately adapt the exposure time. (Intensity = mean value of the three color channels).
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The histogram will appear during live image acquisition automatically."
In addition, the minimum, mean and maximum intensity values of the cur- rent image will be shown. The percentages refer to the camera's maximum possible value. For a 12-bit camera this value is 4095; for an 8-bit camera 255.Acquiring images
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8) Select the Live overlay check box to be able to write information into the image overlay during live acquisition.
The live overlay is also a necessary requirement for some of the other functions, e.g., partial readout, which you can activate in the camera controls.
9) Select one of four display options in the Image scaling list.
10) Confirm the settings you have made by clicking OK.