We are developing a tool for outside users of the HVEM and IVEM to compliment the mailed-in grid program, and otherwise promote the availability of the instruments. The Website will provide immediate access to images on the HVEM or IVEM, feedback between the remote user and the microscope operator, and methods to survey specimens remotely. The websites will not provide the remote control of the microscopes, which is not practical with the Internet bandwidth available to most users. However, we plan to include remote readout of the microscope stage position, which will be useful for specimen grid mapping. In the case of the HVEM, we use a TV-rate camera developed in-house for image capture. The quality of these images depends mainly on the quality and character of the video phosphor screen used for image conversion from electrons to light. We have learned how to make these screens with very good uniformity and resolution. We can adjust the trade-off between sensitivity and resolution to optimize the specimen damage versus image quality situation. We plan to implement a basic addition to the HVEM stage controller that would provide coordinate readout. A web server with video capture capability will be used to present the images to a web page accessible to anyone with a standard web browser. In the case of the IVEM, images are captured by the slow-scan CCD camera (part of the Teitz system used for automated tomography), converted to a reduced-size, compressed, web-compatible image format, and put onto the web page. So far, only the HVEM implementation has been started. A simple web server is running on our power Mac. The system is capable of serving a currently-captured image every 4 to 10 seconds. A simple but functional webpage is composed allowing remote users to update the image by pressing """"""""reload"""""""" on their browser. This arrangement either captures images automatically from the HVEM, or permits the HVEM operator to make selections of images and/or drawings to be presented to the webpage. The experimental web server we have currently installed is probably inadequate for the reliability we would expect for our national center (it is essentially """"""""freeware""""""""). It is, however, functional. The local Internet administrators have not yet made this server assessable from outside the firewall.
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