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Screening and Scanning EM Film
Procedure with screen shots available on web site http://www.nysbc.org/facilities/CEM/Zeiss_PhotoScan_Usage.html
Download MSWord format with screen shots at end * Zeiss-Photoscan-Usage.doc:
Contents
General Guidelines
- Always use gloves
- Always have something between the glass plattens to prevent scratching
- Never use compressed air sources (which inevitably contain water or oil),
- use brushes to remove dust or clean glass while wet with glass cleaner - experts only
- Transfer and Delete your images from the local disk immediately after scanning they won't be there when you return
- Turn off scanner when no foreseable use later that day (to preserve lamp hours)
Turning on Scanner
- Scanner should be left on, with the light bulb off
- The on switch of the bulb is on the right side of the scanner, toward the back. Up/down = on/off
- Turn the scanner off then on again using the main on/off switch on the left side of the scanner
- Turn the bulb to the on position
- Computer will beep a few times, then the scanner will do a self-test
- Wait until self test has finished "Self Test OK"
- If no beep and no self test initiated, please call for help
- Turn on Windows Computer (open black door underneath scanner and toggle power switch)
- Note that "Carl Zeiss" SCSI device is identified during start up
- Log onto computer
- Open Hyperterminal window (Controller Hyperterminal icon on Desktop - should open automatically)
- Start the Zeiss Photoscan software
- Should get a bunch of messages from the scanner in the Hyperterminal window
Loading the film
- Use gloves
- Open cover
- Raise upper glass platten, which can be held up by the cover
- Remove dust from film and glass with brush
- Do not use glass cleaner without assistance from NYSBC staf)
- Place film on lower glass platten emulsion down
- Cutout corner goes on the upper left
- Lower upper glass platten
- Glass will break if cover is lowered first
- Lower cover
Starting program
- Open Photoscan program, if not already started
- Select File -> New Scan
- Scan Setup - select nysbc_def.par
- Save setup parameters in your own file by changing nysbc_def.par and hitting save
Preview film
- Select file name on "Scan Setup" tab (e.g., E:\stokes\test-mrcgrid.tif)
- Select course Resolution on "Scan Setup" tab (e.g., 28 um)
- Make sure "Overview" is set for "None"
- Should not need to change anything on "Camera Definition" tab
- Select wide range for OD on "Film/Output" tab (e.g., 2.0 to 0.2)
- Save setup parameters (program crashes periodically)
- Select Scan -> Scan to Disk from main menu (F7)
Check normalization data
- Upon initiation of first scan of the day, a normalization is automatically done.
- Look at Hyperterminal window specifically for the following data * Information appears on monitor on top of scanner. Watch closely as it will scroll off screen.
| No. of ff-values: | B 0 | G 0 | R 0 |
| Minimum-values: | B 205 | G 215 | R 209 |
| Maximum-values: | B 245 | G 251 | R 250 |
| Measured with Exposure Time: 2.10 ms ok. |
- Min values should be within 50-60 of max values
- Max values should be < 255
- Three channels should be within 20 counts of one another
| No. of 0-values: | B 0 | G 0 | R 0 |
| Minimum-values: | B 3 | G 2 | R 3 |
| Maximum-values: | B 7 | G 4 | R 5 |
- Max values should be < 10 with no zeros
| No. of gain-values cut to 2047: | B 0 | G 0 | R 0 |
| No. of gain-values cut to 0: | B 0 | G 0 | R 0 |
| No. of offs-values cut to 2047: | B 0 | G 0 | R 0 |
| No. of offs-values cut to -2048: | B 0 | G 0 | R 0 |
- Number of values cut should all be zero
- Any anomalies may indicate time to change the light bulb
Select Scan Area
- Use "Define Scan Area" tool along top tool bar (or in "View" menu)
- Adjust size of box to that desired for final scan
- Select File -> Scan Properties
- check Histogram tab and adjust OD range under Film/Output
- adjust Resolution (e.g. 7 um)
- adjust image size (select "pixels" and enter size)
- Save setup parameters
- please use your own file
- program will be crashing soon, but parameters will be saved
Final Scan
- Select Scan -> Scan to Disk (or hit F7)
- Select File -> Scan Properties and look at Histogram tab
- Adjust any parameters if you want to rescan the image
- OD range usually adjusted so that the densities comfortably fit within the chosen OD window.
- However, at 7 um scan, min OD >0.6 is likely to cause an error (scanning hangs at the end of the 1st swath). If so, wait 3-4 minutes for a SCSI timeout. Lower the min OD value to 0.5 and rescan. This does not appear to be a problem with 14 um scan.
- Save the setup parameter file (please use your own file)
- Close window with image and agree to save the corresponding file
- (otherwise will be deleted)
Shutdown
- Exit Photoscan
- Remove film from scanner
- Replace rubberized insert between glass plates (brush off any dust first)
- Be mindful of upper glass platten before closing lid
- Shutdown computer
- You can leave computer on if returning in foreseeable future.
- However, SCSI connection between computer and scanner seems to get corrupted after significant periods of time.
- Turn off scanner light bulb (right side of scanner, towards back
- Leave scanner itself on, as it sometimes has problems starting from a cold-state
Burn CD
- Open door to lower computer (black door under scanner)
- Insert blank CD in the drive
- Open "Nero Express" on desktop
- Select Data -> Data Disk and select files to include on CD
Transfer files to File Server (dl380)
- Run the sftp software (icon on Desktop)
Transfer files to USB stick
- Connection is via an extended USB cable
- Speed is slow (USB1) so be patient
- Open "My Documents" on desktop or "Windows Explorer" from Start Menu
- Hit "Search", select "Computers", enter "dl380"
- Locate your home directory (select user name twice for your home directory)
- Open second "My Documents" and locate your scanned files on the local disk
- Copy and Paste from CD to dl380 file server
Troubleshooting
- Call staff for any problems starting or completing scans
- If you cannot log in to dl380, just burn a CD
- Contact staff if blank CD's are not available in scanner room
- Photoscan software crash:
- In event of a crash, try restarting Photoscan program
- If simple restart doesn't work, try logging out of Windows PC and logging back in
- If logout/login doesn't work, try rebooting Windows PC
- If you still cannot connect, turn off Windows PC, turn off scanner, and restart from scratch
- Zeiss scanner errors
- Please contact staff if scans fail to complete or normalization fails
Visit Cryo EM Web site at http://www.nysbc.org/facilities/CEM
-- DavidStokes - 18 Mar 2005
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