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This shows you the differences between two versions of the page.

--- chara:operating_procedures [2019/06/06 21:35]
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+++ chara:operating_procedures [2019/06/06 21:36]
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 [[https://docs.google.com/document/d/1b1f0pgeeKOx5NO-jUOCbFM-e7b9GL8iBMFijD1B3Qc8/edit#|Telescope AO User Manual]]\\
 [[https://docs.google.com/document/d/1TnLxWaAw42DZwh7l6_wPfe_CpIfT935_aShK0ymBX1o|WFS TT Alignment and Usage]]\\
-[[https://docs.google.com/document/d/1UY5C8Pkbi_yd448aF_TXXE9KFkwjd5VK3LALvkFahjQ/|WFS TT Alignment and Usage]]\\
+[[https://docs.google.com/document/d/1UY5C8Pkbi_yd448aF_TXXE9KFkwjd5VK3LALvkFahjQ/|Coude alignment (daytime)]]\\
 {{:chara:files:s2_new_finder_camera-r1.docx|New S2 Finder Instructions}} \\
 [[:chara:night_time_pop_changes|Night-time POP Changes]]\\
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-**Chapter 4: ** ===  = Observing Conditions ====\\
+**Chapter 4: ** === = Observing Conditions ====\\
 \\
-Picture_4.png     === 4.1 Observing Conditions Intro ===\
+Picture_4.png === 4.1 Observing Conditions Intro ===\ \ In opening the CHARA Array, conditions should be, for the most part, ideal. If the weather is questionable, it is best if the sky is 60% to 70% clear and conditions stable before commencing. Delicate optics and electronics make up the majority of the Array and it’s better to err on the side of caution. In preparation for observing, the Mount Wilson weather server and web-based weather pages should be consulted. The telescopes can now be closed in about 10 minutes from the control room. With this in mind, don’t open up the telescopes to observe if conditions can change for the worse rapidly enough that you don’t get 10 minutes or more to close down safely. Weather stations now exist at each bunker and there is a control system software application to display the current conditions. Soon this application will also issue warnings. One can also use the white Radio Shack thermometer/hygrometer outside of the control room. With the Array becoming more fancily automated and weather monitoring technology becoming more robust (weather servers, satellite images, web cams, etc.), almost all weather monitoring can be done seemingly without ever leaving the cozy control room. Unfortunately this is not a good policy and nothing beats going outside for a gander and giving the sky a good old fashioned assessment. Obviously weather variations do exist from telescope to telescope, as much as 16% in RH at times. Most of the time this just means something is blowing through and opening is not a good idea. These circumstances need to be dealt with cautiously depending on the given weather conditions. Allowing extra time to close is advised in case of any problems. If any questions or doubts arise contact one of the CHARA staﬀ. === 4.2 Humidity ===\ \ Only open the telescopes if the humidity is steady or dropping, at 75% or below. If the roofs outside the control room are ever dripping, then the telescopes should not be opened or should be closed immediately. If when starting out, the RH is above 80%, do not open unless it drops to below 75% and stays there for at least 30 minutes. If you do open after that, be wary and watch the RH, and if it starts rising, be prepared to close. Closing up takes about 10 minutes, so be ready for that. The array operator is in charge of protecting the telescopes and makes the final decision on whether the conditions are safe to open. If the RH is low at the beginning of the night, and rises after you are already open, the array operator should inform the PI around 70-75%, and start closing between 80-85%. Other humidity warning signs are: 1) water dripping oﬀ the OPLE building (or wet spots on the asphalt straight down from the eaves); 2) cold, clammy feel to metal objects such as railings; and 3) dew forming on the parked cars. It is important to note that the humidity can rise from 50% to 80% in as little as 10 minutes, so please keep a close eye on the rate of change of the humidity plots. It can also rain from passing clouds when the humidity is quite low, even 50% RH or lower. If in doubt, stay closed. === 4.3 Dust ===\ \ Gauging the airborne dust is problematic because you need a bright light and a relatively dark night. In general, you want to look in the bottom 0.5 meter of the light column. There will be a diﬀuse column lit up by the beam – don’t worry about it, just follow the dust glints. If you can count the dust glints, the conditions are safe to observe. If it looks like a blizzard, close up. If any of the dust glints shine with an orange or a peach hue, or the dust glints look abnormally large, the dust is probably ash – close up immediately. Ash seriously degrades bare aluminum coatings. Dust and wind go together. But, just because it is calm, the dust conditions might still be bad. If it was windy a few days earlier, it could have kicked up a lot of dust, which can take several days to settle. Finally, during late spring to early summer, conifer tree pollen can be problematic. If particulates are borderline please email the CHARA day staﬀ so they can clean the optics as soon as possible. === 4.4 Wind ===\ \ Wind has the eﬀect of degrading the seeing as well as kicking up dust. The wind eﬀects are ampliﬁed in the tunnel between the OPLE building and the oﬃce building, so look for other places to gauge the wind conditions. The intersection of the road and the trail to the eastern telescopes is a good place to gauge conditions. To be on the safe side, we only observe under calm to light breeze conditions (gusts less than about 10 knots, or 15 kph). Windy conditions we try to avoid. If you can hear the gusts from your desk, it is too windy to observe. If you hear whistling from the light pipe supports, it is too windy to observe. If you hear the signs on the chain banging, it is too windy to observe. Occasionally you will hear the wind rustling the tops of the tall trees, but it is calm at ground level. This is a symptom of chaotic wind conditions, and almost always happens during windy episodes (Santa Anas, onshore ﬂows, etc.), during which you shouldn’t observe – the seeing will be bad anyway. Be cautious about opening if wind gusts are above 15-20 kph; winds this high are usually correlated with bad seeing and poor data quality. Telescopes and domes should be closed if the wind gusts get up to 30 kph. This will protect the optics from branches and debris that can be blown in from the surrounding trees. === 4.5 Snow ===\\
-\
-In opening the CHARA Array, conditions should be, for the most part, ideal. If the weather is questionable, it is best if the sky is 60% to 70% clear and conditions stable before commencing. Delicate optics and electronics make up the majority of the Array and it’s better to err on the side of caution. In preparation for observing, the Mount Wilson weather server and web-based weather pages should be consulted. The telescopes can now be closed in about 10 minutes from the control room. With this in mind, don’t open up the telescopes to observe if conditions can change for the worse rapidly enough that you don’t get 10 minutes or more to close down safely. Weather stations now exist at each bunker and there is a control system software application to display the current conditions. Soon this application will also issue warnings. One can also use the white Radio Shack thermometer/hygrometer outside of the control room. With the Array becoming more fancily automated and weather monitoring technology becoming more robust (weather servers, satellite images, web cams, etc.), almost all weather monitoring can be done seemingly without ever leaving the cozy control room. Unfortunately this is not a good policy and nothing beats going outside for a gander and giving the sky a good old fashioned assessment. Obviously weather variations do exist from telescope to telescope, as much as 16% in RH at times. Most of the time this just means something is blowing through and opening is not a good idea. These circumstances need to be dealt with cautiously depending on the given weather conditions. Allowing extra time to close is advised in case of any problems. If any questions or doubts arise contact one of the CHARA staﬀ. === 4.2 Humidity ===\
-\
-Only open the telescopes if the humidity is steady or dropping, at 75% or below. If the roofs outside the control room are ever dripping, then the telescopes should not be opened or should be closed immediately. If when starting out, the RH is above 80%, do not open unless it drops to below 75% and stays there for at least 30 minutes. If you do open after that, be wary and watch the RH, and if it starts rising, be prepared to close. Closing up takes about 10 minutes, so be ready for that. The array operator is in charge of protecting the telescopes and makes the final decision on whether the conditions are safe to open. If the RH is low at the beginning of the night, and rises after you are already open, the array operator should inform the PI around 70-75%, and start closing between 80-85%. Other humidity warning signs are: 1) water dripping oﬀ the OPLE building (or wet spots on the asphalt straight down from the eaves); 2) cold, clammy feel to metal objects such as railings; and 3) dew forming on the parked cars. It is important to note that the humidity can rise from 50% to 80% in as little as 10 minutes, so please keep a close eye on the rate of change of the humidity plots. It can also rain from passing clouds when the humidity is quite low, even 50% RH or lower. If in doubt, stay closed. === 4.3 Dust ===\
-\
-Gauging the airborne dust is problematic because you need a bright light and a relatively dark night. In general, you want to look in the bottom 0.5 meter of the light column. There will be a diﬀuse column lit up by the beam – don’t worry about it, just follow the dust glints. If you can count the dust glints, the conditions are safe to observe. If it looks like a blizzard, close up. If any of the dust glints shine with an orange or a peach hue, or the dust glints look abnormally large, the dust is probably ash – close up immediately. Ash seriously degrades bare aluminum coatings. Dust and wind go together. But, just because it is calm, the dust conditions might still be bad. If it was windy a few days earlier, it could have kicked up a lot of dust, which can take several days to settle. Finally, during late spring to early summer, conifer tree pollen can be problematic. If particulates are borderline please email the CHARA day staﬀ so they can clean the optics as soon as possible. === 4.4 Wind ===\
-\
-Wind has the eﬀect of degrading the seeing as well as kicking up dust. The wind eﬀects are ampliﬁed in the tunnel between the OPLE building and the oﬃce building, so look for other places to gauge the wind conditions. The intersection of the road and the trail to the eastern telescopes is a good place to gauge conditions. To be on the safe side, we only observe under calm to light breeze conditions (gusts less than about 10 knots, or 15 kph). Windy conditions we try to avoid. If you can hear the gusts from your desk, it is too windy to observe. If you hear whistling from the light pipe supports, it is too windy to observe. If you hear the signs on the chain banging, it is too windy to observe. Occasionally you will hear the wind rustling the tops of the tall trees, but it is calm at ground level. This is a symptom of chaotic wind conditions, and almost always happens during windy episodes (Santa Anas, onshore ﬂows, etc.), during which you shouldn’t observe – the seeing will be bad anyway. Be cautious about opening if wind gusts are above 15-20 kph; winds this high are usually correlated with bad seeing and poor data quality. Telescopes and domes should be closed if the wind gusts get up to 30 kph. This will protect the optics from branches and debris that can be blown in from the surrounding trees. === 4.5 Snow ===\\
 Because of the nature of the snow that falls on Mount Wilson, it is usually not a problem. If snow/wind conditions are such that drifting occurs, don’t open up. If there is still any snow stuck to the telescope dome itself, don’t open up. If there is snow still on the trees and branches procede with caution and make a visual assessment. Otherwise, you are free to observe (assuming the humidity, dust, and wind conditions allow it). === 4.6 Essential Observing Links === * 150-Foot Solar Tower Current TowerCam Image ([[http://www.astro.ucla.edu/%7Eobs/towercam.htm|http://www.astro.ucla.edu/~obs/towercam.htm]]) a live view of the mountain. Check the clock when viewing the page as it can sometimes fail to refresh. * Caltech Millikan Library Camera ([[http://library.caltech.edu/milcam/|http://library.caltech.edu/milcam/]]) A view of Mt. Wilson from the south, good for watching low clouds and fog that cling to the mountain. * National Weather Service ([[http://forecast.weather.gov/MapClick.php?site=lox&textField1=34.2231&textField2=-118.0587&smap=1#.VKsuq2TF8rO|http://forecast.weather.gov]]) Mount Wilson weather and 5 day forecast * CHARA telescopes spy cams and weather graph ([[http://astro.gsu.edu/~weather/chara_scopes.html|http://www.astro.gsu.edu]]) Status of each CHARA telescope * Mount Wilson HP Wren Cameras ([[http://hpwren.ucsd.edu/cameras/wilson.html|http://hpwren.ucsd.edu/cameras/wilson.html]]) * Aerospace Corporation weather station ([[http://www.weatherlink.com/user/mocam/index.php?view=summary&headers=1|http://www.weatherlink.com/user/mocam]]) Another local station, always current. * Jet stream forecast ([[http://squall.sfsu.edu/scripts/jetstream_modelsml_fcst.html|http://squall.sfsu.edu/scripts/jetstream_modelsml_fcst.html]]) Monitors high level winds which degrade seeing * IR satellite loop ([[http://www.wrh.noaa.gov/lox/scripts/animate.php?root=sat_4km&list=IR4.GIF.3.jpg,IR4.GIF.4.jpg,IR4.GIF.5.jpg,IR4.GIF.6.jpg,IR4.GIF.7.jpg,IR4.GIF.8.jpg|http://www.wrh.noaa.gov]]) Keeps an eye on storms and clouds coming in * California Regional Weather Server ([[http://squall.sfsu.edu/|http://squall.sfsu.edu/]]) A variety of weather links * Clear Sky Clock ([[http://cleardarksky.com/c/MtWilsonOBCAkey.html|http://cleardarksky.com/c/MtWilsonOBCAkey.html]]) a forecasting tool, but be aware that the humidity forecast is often incorrect on this site as it incorporates the marine layer forecast for the valley below, which does not affect us 80-90% of the time\\
-[[:chara:operating_procedures|Back to Main Menu]]\
+[[:chara:operating_procedures|Back to Main Menu]]\ \ {{:chara:files:picture_6.png|Picture_6.png}}\\
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-{{:chara:files:picture_6.png|Picture_6.png}}\\
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 [[:chara:operating_procedures|Back to Main Menu]]\\
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-**Chapter 6:** ===  = Procedure for Shutting Down at the End of the Night ==== === 6.1 End Night Sequence Introduction ===\\
+**Chapter 6:** === = Procedure for Shutting Down at the End of the Night ==== === 6.1 End Night Sequence Introduction ===\\
 \\
 The End Night sequence on Cosmic Debris can be used to end observing and stow the telescopes, carts, and domes. It will only stow the active scopes, carts, and domes, so if there are other scopes open, make them active in the Configure tab of CD or stow them manually with the procedure below, 6.4 Manually Stowing the Telescopes === 6.2 Start the end night sequence on Cosmic Debris === * Clear the job queue on Cosmic Debris. * Press the [END NIGHT] button on Cosmic Debris. This will close all the shutters, stow the active telescopes, close the telescope mirror covers, send the OPLE carts to the back switch, close the OPLE socket, and archive the accumulated data for the night. * NOTE: The End Night Sequence will NOT close the dome slits so these will have to be closed manually after all of the telescope mirror covers are closed. It will also not send inactive carts back. Update the configuration with any inactive scopes to make sure those carts can be sent back manually as well. * The Cosmic Debris status window will indicate when the end night sequence is complete. You can close Cosmic Debris after you have sent out the Observing Report. * If you use the End Night sequence to stow the telescopes and close mirror covers, remember to do a visual check of all telescopes using the check list in step 6.4 below before turning off the power for the telescopes and closing the telescope GUIs.\\
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 In addition to paper observing logs, CHARA offers the option of using electronic logs. At minimum, we request that you fill out the date, UT time, target name, and any comments that would be relevant for subsequent reduction. This information will be useful for building and maintaining the CHARA archive:\\
-CHARA Electronic Logs   === 6.3 Shutdown Checklist Introduction ===\\
+CHARA Electronic Logs === 6.3 Shutdown Checklist Introduction ===\\
 \\
 It is important to make sure the array gets shutdown properly at the end of the night. This includes stowing the telescopes, closing the mirror covers and domes, powering down equipment, and covering the cameras. Each day many employees are working on various systems from any number of diﬀerent locations around the Array. Any CHARA equipment left on or exposed, can cause damage to other systems or be damaged itself. It is critical that the array is shut down consistently from night to night. Listed below are the procedures for shutting down the array. Please make sure that the Array is secure at the end of the night. === 6.4 Manually stowing the telescopes === * Unlock the tiptilt beams using the Tiptilt servo control GUI. * Turn the telescope TVs to SPY1 so that you can watch the telescopes. * On the Control Tab of the telescope GUI, click [STOW]. This will send the telescope and dome to the stow position. * When the telescopes reach an elevation above 70 degrees, you can begin closing the mirror covers. * M1 CLOSE * M3 CLOSE * M5 CLOSE * M7 CLOSE * Finder CLOSE Note that W2 and E1? covers need a second click to close. * Visually inspect the telescopes using SPY2 to make sure that the mirror covers close properly. Check the Telescope Monitor for mirror cover status. * After all of the mirror covers finish closing, close the dome slits by clicking [SLIT CLOSE] on the telescope control tab for each telescope dome that is open. * Close the dome enclosures by clicking [CLOSE] on the cylinder GUI. Watch that each reads .000 or .001 when closed. * Check that the telescopes moved to their stow positions in EL and AZ: * EL 90.0 deg, AZ 55.9 deg for E1 and E2 * EL 90.0 deg, AZ 99.3 deg for W1 and W2 * EL 90.0 deg, AZ 82.0 deg for S1 and S2 * Turn off the power for [TEL AZ], [TEL EL] and [TIP/TILT] for the active scopes using the Power GUI. * Visually check all telescopes in the spycams to make sure all covers and slits are closed. * Leave the telescope GUIs open until the End Night Sequence is finished. (Cosmic Debris will turn on the TVs and the SpyCams during the End Night Sequence.) * If the humidity is high, make sure that the heaters are turned on. === 6.5 Send the OPLE carts to the back of the rails === * Click the OL and MAN buttons for the active carts on the OPLE GUI Control Tab so that the buttons turn green. * Turn the carts OFF using the OPLE GUI. * Click BACK on the OPLE GUI to send the carts to the back. * Watch OPLE Server for Back Switch indicator to light up with an "X". * When all carts are on the Back Switch, close the OPLE gui and server and turn off the metrology laser using the METLAS GUI. The [LASER POWER] button will turn from green to red. If a cart does not reach the back switch, it may have caught the ribbon or cable on the track supports. You will need to go to the rails and see why it stopped. Slack in the cable can be taken up by turning the take up spool by hand. W1 cart is the usual one that hangs up. === 6.6 Finish shutting down in the control room === * If using Classic or CLIMB, check to make sure the dither is off by looking at the dither status in the CLASSIC/CLIMB server. If necessary, this can be turned off from the dither tab on the Classic/CLIMB GUI. They are off when gray. * Shut off [METSCOPE], [NIRO CPU], and [CLS-DITH], or [CLM-DITH] if used on the POWER gui. * Close the OPLE, Tiptilt, CLIMB/CLASSIC GUIs * Close the OPLE, Tiptilt, and CLIMB/CLASSIC servers, type CTRL+C, then Y * Visually check all telescopes in the spycams to make sure all covers and slits are closed. Turn the TV to Finder, then turn the TV OFF, and close the telescope GUIs. * Leave GPS server and the Telescope Servers open and running === 6.7 Shutting down the Lab ===\\

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