Work Items and our flight schedule Dear Hamed, We have discussed what we shall do at Kottamia. Here are our proposal of work items at Kottamia during our visit between Nov.14 and Nov.25 1. AT first we should adjust Axial Support(AS) system of the mirror to get good image quality of your telescope. Current image quality has been measured as 0.7 arcsec of Hartmann constant using Hartmann test images taken on June 21, 2009. This Hartmann constant is not good compared to initial data of 0.12 arcsec presented by Carl-Zeiss. So we'd like to measure and adjust about AS. 1.1 to adjust the Axial Balance Weights equality to all, as weights for AS7 and AS9 are a little bit heavier. After then, we check how every AS pad touchs the back surface of the mirror? For this work we take a precise weight/force-measuring tool. 1.2 After adjustment of equal weight of ASs and there is still some gap between the mirror back surface and AS pad for some pad(s), we'd like to enlarge the limiter hole using a bit machine. ( Limiter hole is just before the AS counter weight.) For this work we need a bit machine. 1.3 We'd like to investigate how the Radial Supports affect the mirror shape. We measure the shape and force acting with the Radial support. For this work, we'd like to use dial gauge with its magnet base, which we have taken to Kottamia on our previous visit. To Confirm this work, we'd like to get Hartmann test image and/or Shack-Hartmann image. 2. When we observe several objects using Newtonian focus, we recoginized image shift between objects in northern sky and in souther sky. Possibly the Newtonian mirror may be moved inside the mirror cell. We'd like to check which causes the shift. If some gap between the mirror and its cell, we put some rubber plate between them. For this work, we take rubber plate of thickness of 1 or 2 mm of Teflon. Also we take some supporting base(tool) to disassemble/assemble the Newtonian Cell. After this work, we'd like to check the image shift between northern sky and souther sky by observing astronomical objects with Newtonian focus. 3. We believe a calibration procedure is necessary for modern astronomical observation using a dome flat illumination. At Okayama observatory we use a projector lamp as light source and SORIC screen as reflective sheet. SORIC screen is commonly used for world-wide astronomy. We have its info on http://www-irc.mtk.nao.ac.jp/~sasaki/Kottamia/index.html#DomeFlat http://www-irc.mtk.nao.ac.jp/~sasaki/Kottamia/DomeFlat/Subaru_DomeFlat_SORICScreen.pdf We'd like to discuss with you what you like to install a dome flat. If possible we'd like to design the dome flat system at Kottamia. 4. As Prof. Noguchi and Eng. Koyano have know-how very well on Aluminizing proces of the mirror, we'd like to discuss how to improve the Aluminizing process. Possible candidate is to install a pre-wet process of Aluminum onto the filament which are used in an aluminizing chamber. We'd like to discuss more at Kottamia. 5. As dust accumulates on the mirror surface, especially at Kottamia, we'd like to recommend to install mirror cleaning tools with CO2 (carbon dioxide) snow, which are made from CO2 gas. We discuss about CO2 snow and when you agree we try to get some fund to install CO2 snow system at Kottamia. 6. We think there is several choice to improve obsering performance, especially on Cassegrain focus. Possible candidates are; 6.1 to install optical baffle to reject slantingly-injected light and stray-light at Cassegrain focus. Sample of Cs baffle is seen on http://www-irc.mtk.nao.ac.jp/~sasaki/Kottamia/Photos/OAO20090917_HTML/100_6200.html http://www-irc.mtk.nao.ac.jp/~sasaki/Kottamia/Photos/OAO20090917_HTML/100_6201.html These are Photos of Cs baffle at OAO. 6.2 to introduce Focal Reducer at Cs focus to get FOV matched CCD imager, becasue a Coma-free field at Newtonian focus is about 2 arcmin in diameter and FOV of CCD camera is 10 arcmin which is much wider than Coma-Free FOV at Newtonian. When we can introduce a focal reducer with good design, we can get Coma-free FOV matching of the size of CCD camera. A design of a focal reducer is now being progressed by Prof. Nariai and Prof. Noguchi. We can discuss more at Kottamia, I hope. 6.3 How to set up Cs II spectrograph, which has been supplied from OAO. We are now considering to introduce some remotely-controlled functions for a comparison lamp, an optical shutter, a guiding CCD camera, and more for operations of an off-set mirror, grating angle, slit-width, so on. 6.4 Coma-corrector for Newtonian focus is now designed by Prof. Nariai and Prof. Noguchi. When we get a good design of the Coma-corrector, we can select which is better among a Coma-corrector at Newtonian, a Foca-Reducer at Cassegrain, or both. We have two questions. How about your adjustment of the mirror support system by measuring your Shack-Hartmann device? Do you have good results? We saw a bit machine at Kottamia at our last visit. Can we use the bit machine at our next visit for our works? If not, we prepare a small bit machine for our works. As his new passport is delivered today on Oct 15, I'll send an Eng. Koyana's Passport copy in a separate mail. I am visiting China for astronomical site survey in west China during Oct.19 and Nov 9. During this period I am difficult to read e-mail as there is no available internet connection in west China, say a wild field in west Tibet :-). So please contact Prof. Noguchi if you have questions and comments: his e-mail address is of takeshi_noguchi_15@ybb.ne.jp and also Eng.Koyano's addres of koyano@oao.nao.ac.jp. Our flights are as follows: Nov 13 (Fri) Haneda/Japan 19:55 -> Osaka/Japan 21:10 Emirates Airline EK6257 Osaka/Japan 23:20 -> Dubai Nov.14 05:40 Emirates Airline EK 317 Dubai Nov.14 08:50 -> Cairo Nov.14 10:55 Emirates Airline EK 927 Nov 25 (Wed) Cairo 19:15 -> Dubai Nov.26 00:25 Emirates Airline EK 924 Dubai Nov.26 03:30 -> Osaka Nov.26 17:20 Emirates Airline EK 316 Osaka Nov.26 19:15 -> Haneda Nov.26 20:25 Emirates Airline EK6252 So please pick up us at Cairo airport on Nov 14. Best regards, Sasaki