Related Manuals for Hitachi HT7800
Summary of Contents for Hitachi HT7800
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Page 1: Table Of Contents
Hitachi HT7800 user guide System overview column page 2 Control panel overview page 3 Start up / shut down routine page 4 Holder - Sample mounting page 5 Inserting and removing sample holder page 6 The process of exchanging samples... -
Page 2: System Overview Column
Cold fingers – only used when needed Condenser aperture Sample holder Objective aperture (automized) Goniometer switch panel Power switch panel EMERGENCY OFF switch (should be used in case of an emergency like water leakage or fire exposure). Special procedure must be COL power switch followed for switching EVAC power switch... -
Page 3: Control Panel Overview
Control panel overview Turns off the Goes to live mode Resets filament and HV lenses (use if you get lost) Auto focus to go back to start Switch between Screen and Main camera Captures and saves image Wobbler is used to adjust for eucentric height or focus... -
Page 4: Start Up / Shut Down Routine
Insert holder and follow the evac procedure to fully insert the holder. Turn off “HV on” from the control panel. Close the HT7800 software. Shut down the computer (start menu + shut down). Leave COL power ON (we turn it off during vacations). -
Page 5: Holder - Sample Mounting
Holder - Sample mounting Mounting the sample is a delicate process and the sample holder needs to be handled with great care. Please be especially careful to only load completely dry samples. • The holder should have been left inside the column (without evac) away from dust. Remove holder. -
Page 6: Inserting And Removing Sample Holder
Inserting and removing sample holder • Remove the sample holder from its stand. Insert the holder carefully and align the pin with the opening in the goniometer. Push until it stops. • Set the goniometer switch to “evac” (the evacuation of the prechamber starts). •... -
Page 7: The Process Of Exchanging Samples
The process of exchanging samples Switch over to the screen camera (press F1). Go down in magnification. Click holder reset in the stage operation window. Remove the holder by following the guidelines (more info on page 6). Place holder in it’s stand and carefully open top lid and remove your samples. -
Page 8: Software Overview
Software overview Information about magnification, kV, filament V and vacuum condition Turning On/Off HV, filament V and beam bias. You can adjust “live” camera exposure here as well as black/white and gamma levels. The “R” will refresh and “auto LUT” will automate the lookup table. You will create a “whole”... -
Page 9: How To Start Your Imaging
How to start your imaging Insert your sample holder and perform a beam shift horizontal alignment (page 17). Open the Stage operation window. Select the field mode you want to use (HC=high contrast, magnifies up to 200.000 or HR=higher resolution, magnification between 200-600.000). Select the correct holder and specific holder position your want to image. -
Page 10: Adjusting Image Display And Camera Capture
Adjusting image display and camera capture To acquire images with high quality use the MAIN camera! The camera display, white/black values and The camera exposure and gain can be gamma can be changed. If “Auto LUT” is checked, changed for the live mode. “R” is to reset. the values change automatically. -
Page 11: Camera Capture Parameters
Camera capture parameters (MAIN camera) Capture exposure: increasing the exposure time will give less noise and a smoother image with more details. If the exposure is too long, you might experience unsharp image due to drift. Try using between 300-600 ms. 150 ms 600 ms 900 ms... - Page 12 Camera capture parameters (MAIN camera) Capture gain (dB): Range between 0-20, default is 0 For normal samples, we use capture gain 0. In the example under you can see that gain 8 gave an overexposed image. It can be a bit challenging to define the capture gain especially if you leave the live gain very high.
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Page 13: Save File Setting
Save file setting • Define the save file settings inside the camera operation window, under file. This option should always be checked in order to protect the camera chips from long exposure of the frozen image. Once you have acquired an image, it will automatically be saved and the frame will go back to live. - Page 14 EMP-EX software – this is optional The acquired image will show up in the Thumbnail window. Double click the image to open it up in Hitachi EMIP-EX software. Here you can make measurements and change contrast on the image if needed.
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Page 15: How To Use Autofocus
How to use autofocus The autofocus works by searching for contrast changes in the middle of the image (10% of the center). If the signal is low there or structures are missing, autofocus will fail. Solution: Move your sample in order to place something with more contrast in the middle of the image. -
Page 16: Beam Cross Over
Beam cross over • The brightness knob controls the beam. By turning the knob to either direction, you will spread the beam or center the beam into a spot. • For optimal focus condition, you need to be on the right side of the crossover, ie you increase the light (the beam gets smaller) by turning the brightness wheel anti-clock. -
Page 17: Beam Shift Horizontal
Beam shift horizontal Why do we need to shift the beam? - To get optimal resolution, contrast and enough light. If you notice that a shadow sneaks into your image, it’s most probably because the beam is not in the centered. Use the X and Y under alignment and shift the beam to the center. -
Page 18: Auto Multiple Frames (Amf)
AMF – Auto multiple frames It is possible to create up to 4x4 tile scan with the Main camera using the AMP function. • Open the Auto multiple frames (AMF) under Function (A). • Define where your images should be saved under “quick save file setting”... -
Page 19: Column Mode Operation
Column mode operation Common users will not change these options. Brightness link should Spot number/size be checked to (1= smallest, 5= largest) The facilitate transition smaller the spot, the more between light you get. Generally spot magnification and size 3 is ok to use. beam brightness. -
Page 20: Common Nomenclature Explained
Common nomenclature explained The system can operate from 0-120 kV. The higher the V, the “harder” the electrons will hit your sample. For biological samples, try using kV between 60-100 kV. Filament V The voltage is set by the technician when the filament is saturated (a process involved in the filament mounting). -
Page 21: Troubleshooting
Troubleshooting Image looks grainy and has low contrast. You might need more signal to the camera. Try increasing the brightness and exposure time... - Page 22 Troubleshooting You are seeing bleached regions in the sample. This new microscope is using a Lab6 filament which is much stronger than the tungsten filament. In addition, the camera is also very sensitive and will more easily pick up contrast changes. The problem could be that the beam is bleaching out the lead staining. Solution: stain with less lead or find another staining method.
- Page 23 Troubleshooting It feels like the automatic exposure is not working, the picture is too light. This will happen every time you have something very dark in the image. The auto LUT takes this dark item into account and therefore the image overall looks lighter. It is easy to adjust the intensities in the image after acquisition by changing the white and black balance and resaving the image.
- Page 24 Troubleshooting I’m missing the scale bar in the image! This will happen when the previous user has turned off “embed of property”. You can find the option under the camera operation window – Image –Embed of property. To remove the details, uncheck all options under “custom property”...