The polarizer quads were also designed to map onto a four-faceted WFC configuration and, consequently, also require a partial filter rotation of -33° to move the filter quadrant 1 (nominal polarization angle 135°) into WFCs 2 and 3, with some vignetting of both camera fields. Several additional partial rotations have been added to allow observations with different polarization angles on the same CCD. ... Table 3.10: Polarizer Quad Filter. ... Filter Name . ... Nominal filter wheel position . ...

... NICS will be the only infrared instrument for the first light of the TNG; as a consequence, we decided to incorporate a sufficient degree of operation flexibility by providing the instrument with six different observing modes, three aimed at imaging and three at spectroscopy: . ... It will be possible to use the narrow band filters as order sorters; this will allow to perform high resolution long-slit spectroscopy in the wavelength ranges covered by the available narrow band filters. ...

Next: OTHER DIGITAL BACKENDS: Up: Wide Band Observing: RDBE, Previous: The RDBE system Contents . The DBBC being developed for the EVN and many geodesy stations is also a system that samples at 512 or 1024 MHz and digitally filters the signals to the desired bandwidths. ... Support for the DDC personality of the DBBC has recently been implemented in SCHED, but should be used with caution. ... The frequencies for the band edges in the DDC personality can be set to any multiple of 10 kHz. ...

... Exposure Time Calculator (ETC) . ... ESO - Public Surveys . ... the recommended values to use for DIT, . ... Detector on-chip integration (DIT): seconds. to your chosen value - a separate page gives recommended values to use for DIT - for modes 1 and 2 below you may wish to start with the maximum recommended values as these will minimize the effect of read noise (a total object exposure of Y secs with DIT=X secs will produce Y/X lots of read noise) and give you a lower limit on the time needed. ...

... Tonight's Sky . ... Observing . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... solar system . galaxies . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Imaging Basics . ... Observing Basics . ... Observing Basics: Visual Solar Filters . ... Expand your observing at Astronomy.com . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...

... Meade Series 4000 Nebular Filters incorporate the very latest in interference coatings technology. ... Technical Basis of the Meade Broadband Nebular Filter: As shown in the transmission graph below, the Meade Broadband Nebular Filter strongly rejects the light of sodium- and mercury-vapor lights as well as natural airglow and auroral emissions. ... Meade Series 4000 Narrowband Nebular Filters . ... Meade Series 4000 Oxygen-III Nebular Filters . ... Meade Series 4000 Photo-Visual Color Filters . ...

... The following charts/text are intended as tools for monitoring the Type Ia supernovae ( SNe ) event visually or photographically (utilizing telescope equipped CCD equipment).The files include: A replication of The Type Ia SNe , V- magnitude (with data point checks from other cited references)and color index (B-V) templete (to indicate a general color-related trend of the type Ia ... I believe this might help alleviate some of the problems involving the making of acceptable amateur light curves...

Next: Reducing the observations Up: PEPSYS general photometry Previous: Influencing the plan . ... If the telescope and instrumentation are unfamiliar to you, you may have trouble keeping to the schedule for the first night or two, so try to work with a previous observer on the equipment for a night or two of training before your observing run. If you fall behind, try to keep as many low-altitude observations of extinction stars as you can, and drop some circumzenithal ones if necessary. ...

At Arecibo we have a variety of optical instruments that we use to study terrestrial airglow emissions. ... As a complement to the airglow instrumentation we also maintain a set of optical instruments, called lidars, used for "active" remote sensing of the atmosphere. That is, we generate our own source signal using lasers and measure the characteristics of the light scattered back from the atmosphere. ... An operations manual for the Optical Laboratories is currently under major revision. ...

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... Filters and SPIcam's Filter Wheel . Mounting filters in SPIcam's Filter Wheel . Updating the filters.txt file . ... note which filters are in which slot, so you can update the filter file (next) Updating the filters.txt file . ... edit the [filters#.txt] file that corresponds to the wheel which you changed. (e.g. filters3.txt for wheel #3) . ... if this filter wheel was installed in SPIcam, replace the [filters.txt] file with the contents of the file you just updated: . ...

... ESO, the European Southern Observatory . ... Travel and Contacts . ... Green ESO . ... Survey Telescopes . ... 2002 . ... Images of Titan taken on November 26, 2002 through nine different filters to probe different altitudes, ranging from the stratosphere to the surface. ... Due to these good observing conditions, Titan's trailing hemisphere was observed with contrasts of about 40%, allowing the detection of several bright features on this surface region, once thought to be quite dark and...

... Observing . ... Home Observing Poe Park, The Bronx ? Solar Observing . ... Poe Park, Bronx, Solar Observing . ... Observing Out-Of-Town . ... Beyond New York City . ... Observing Resources for Amateur Astronomers - Part 1: Beginning Observers . Observing Resources for Amateur Astronomers - Part 2: Intermediate Observers . ... A History of the First Forty Years of the Amateur Astronomers Association . ... 2016 Amateur Astronomers Association of New York Designed by Press Customizr Powered by . ...

... The fact that the Sun is a gas, however, lets different regions pass by one another fluidly. ... This differential rotation has interesting ramifications for the Sun's magnetic field. ... This bizarre distortion of the magnetic field results in active phenomena on the surface of the Sun. ... Magnetic instabilities in the solar field cause short, violent ejections of gas called solar flares-the most explosive events on the Sun. ... The Sun can also be viewed safely through special types of filters. ...

Next: NICMOS/HST H-band (F160W) Images Up: NICMOS Science Previous: HST NICMOS Observations of . ... Observations of P . ... The NICMOS team has devised a comprehensive program of observations of the Galactic Center. ... Data in hand give a first look at variability and a detailed look at the search for the tip of the main sequence will be discussed where NICMOS has demonstrated adequate sensitivity and photometric precision to identify likely O8-B1 stars at the Galactic Center. ...

Direct images gallery. Here we have presented some images obtained on SAO telescopes by using SCORPIO. ... NGC 6951 . ... This color image are combined from the frames in the filters V ("blue"), R ("green") and middle-band filter SED755 ("red"). ... The true color image is constructed from three frames in B (Texp=600 sec), V (Texp=480 sec) and R (Texp=400 sec) filters. ... The true color image is constructed from three frames in B (Texp=180 sec), V (Texp=120 sec) and R (Texp=90 sec) filters. ...

... Up: Proposal Processing . ... An automated observing proposal processing system has been in use at KPNO during the past three years. ... Observer and proposal information fields in these files are well-marked with LaTeX tags, thus allowing automated extraction and importation to observatory databases. ... The Kitt Peak observing proposal handling system (Bell et al. 1996) is an automated system for distributing, receiving, and processing LaTeX observing forms and associated PostScript figures. ...

... Star parties can be done with naked eye observing, or with telescopes, as long as your site is reasonably dark enough (or can be darkened). Star parties give students the opportunity to put their observational skills to work, and to directly experience astronomy. ... As mentioned earlier, star parties are also great opportunities to involve families, the school, and the community. ... Fun Star Party Ideas . ... Give students "ASTRO Boxes" containing activities or tasks to do during the star party. ...

Solar Eclipse, 3 October: . ... P.A. gives the position of the start of the eclipse, measured clockwise from North on the Sun's disc. ... A solar eclipse is easily visible even to the unaided eye, although you MUST use a proper solar filter, such as various specially designed eclipse 'glasses' or hand-held viewers, which are safe if undamaged. ... Use your widest-field eyepiece first to locate the Sun, either when looking through a filter, or when projecting the image, then switch to a higher power. ...