<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Checking the link provided by Mark Wagner, I see that one of the filters, KP1391 (6620/67) is listed as KOSMOS-approved. It will be good to verify that this filter does not produce the aberrations described by the observer. The other borrowed filter, KP1565 (6653/68) does not appear on the list of KOSMOS-approved filters. The closest filter listed is KP1494 (6658/84). I will go ahead and see if this filter is currently available preemptively and then plan accordingly once I can discuss things with the observer. I’m a little concerned here though as the observer describes the issue when observing in the “Halpha band”. To me, that description more closely matches KP1391, which is already listed as KOSMOS-approved.<div class=""><br class=""></div><div class=""><div class="">
<div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="orphans: 2; text-align: -webkit-auto; text-indent: 0px; widows: 2; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: 'Lucida Grande'; font-size: 11px; white-space: pre-wrap;" class="">****************************************************** </span></div><div class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><span class="Apple-style-span" style="font-family: 'Lucida Grande'; font-size: 11px; white-space: pre-wrap;">ERIC GALAYDA </span></div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><span class="Apple-style-span" style="font-family: 'Lucida Grande'; font-size: 11px; white-space: pre-wrap;">Site Manager</span></div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><span class="Apple-style-span" style="font-family: 'Lucida Grande'; font-size: 11px; white-space: pre-wrap;">MDM Observatory</span></div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><font face="Lucida Grande" class=""><span style="font-size: 11px; white-space: pre-wrap;" class="">℅</span></font><span class="Apple-style-span" style="color: rgb(0, 0, 0); font-family: 'Lucida Grande'; font-size: 11px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: pre-wrap; word-spacing: 0px; -webkit-text-stroke-width: 0px;"> NOAO (Mailstop MDM)</span></div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><span class="Apple-style-span" style="font-family: 'Lucida Grande'; font-size: 11px; white-space: pre-wrap;">950 N. Cherry Ave. Ph. 520.318.8660/1 </span></div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><span class="Apple-style-span" style="font-family: 'Lucida Grande'; font-size: 11px; white-space: pre-wrap;">Tucson, AZ 85719 email: <a href="mailto:egalayda@umich.edu" class="">egalayda@umich.edu</a></span><span style="font-family: 'Lucida Grande'; font-size: 11px; white-space: pre-wrap;" class=""> </span></div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><span style="font-family: 'Lucida Grande'; font-size: 11px; white-space: pre-wrap; text-align: -webkit-auto;" class="">******************************************************</span></div></div></div></div></div></div>
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<br class=""><div><blockquote type="cite" class=""><div class="">On May 10, 2016, at 9:13 AM, Mark Wagner <<a href="mailto:mwagner@lbto.org" class="">mwagner@lbto.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">I was the one who experienced the image distortion problem before and is described in the link below. The tilt only causes a slight shift in the effective central wavelength of the filter. But, for some of the KPNO NB filters the issue is that they are not flat enough to be used in the OSMOS collimated beam. I say some of the KPNO NB filters because we used two of them in February and there were no issues. These were a pair of 2x2 inch filters that corresponded to a redshifted Halpha line. Unfortunately, you don’t know a priori which NB filters from the KPNO inventory can be used successfully in OSMOS. However, there is a list of approved KOSMOS 4” filters given on the KPNO web site. These might be the place to start.<br class=""><br class=""><a href="http://www.noao.edu/kpno/filters/KOSMOS_KPNO_FILTERS.html" class="">http://www.noao.edu/kpno/filters/KOSMOS_KPNO_FILTERS.html</a><br class=""><br class=""><br class="">- Mark<br class=""><br class=""><br class=""><br class=""><blockquote type="cite" class="">On May 10, 2016, at 8:47 AM, Galayda Eric <egalayda@umich.edu> wrote:<br class=""><br class="">Hopefully it should already be known to the observer, but for full disclosure, I suppose it is worthwhile to note that this stems from the filter wheels within OSMOS being aligned at an angle of 8 degrees instead of being orthogonal to the optical axis.<br class=""><br class="">****************************************************** <br class="">ERIC GALAYDA <br class="">Site Manager<br class="">MDM Observatory<br class="">℅ NOAO (Mailstop MDM)<br class="">950 N. Cherry Ave. Ph. 520.318.8660/1 <br class="">Tucson, AZ 85719 email: egalayda@umich.edu <br class="">******************************************************<br class=""><br class=""><blockquote type="cite" class="">On May 10, 2016, at 8:35 AM, Galayda Eric <egalayda@umich.edu> wrote:<br class=""><br class="">I’ve attached some images that last night’s observer has sent along in case anyone from OSU wants to weigh in. See below.<br class="">For the first problem, that dark region on the left of the displayed frames is the guide probe vignetting the image. See the following link:<br class=""><br class="">http://www.astronomy.ohio-state.edu/MDM/OSMOS/#guiding<br class=""><br class="">The second issue is more subtle in nature. Essentially it has to do with the filters being angled inside OSMOS. See a previous trouble report on the same issue:<br class=""><br class="">http://mdm.kpno.noao.edu/index/Solutions_24/Entries/2015/6/11_2.4m%2C_Filter-Dependent_Aberration_with_OSMOS.html<br class=""><br class="">It is worth noting that again, this problem is only being seen with filters being borrowed from KPNO. The only immediate solution I can see to this problem is to pull OSMOS and instead use the filter wheel for mounting the detector, which would lay the filters flat, orthogonal to the optical axis.<br class=""><br class="">—eric<br class=""><br class="">_____________________________________________________________________________________________________________________________________________________________________<br class="">Hey Eric,<br class="">The images I obtained tonight, seems to be a little strange, as shown in the attachment. Do you know what’s the reason?<br class="">Also, as shown in the attachment, there is always a special tail around bright stars in the H alpha band although I changed the colfocus and cam focus.<br class="">By now, I think the images I obtained are useless. So I am wondering could you come to Kitt Peak tomorrow, and see what happened with these images?<br class="">It will be really helpful for my next night…<br class=""><br class="">Thank you very much!<br class="">Zhijie<br class=""><Screen Shot 2016-05-10 at 1.52.23 AM.png><Screen Shot 2016-05-10 at 2.03.24 AM.png><Screen Shot 2016-05-10 at 3.15.08 AM.png><Screen Shot 2016-05-10 at 3.16.22 AM.png><Screen Shot 2016-05-10 at 3.17.21 AM.png><Screen Shot 2016-05-10 at 3.17.45 AM.png><br class=""><br class=""><blockquote type="cite" class="">On May 10, 2016, at 4:31 AM, <obs24m@mdm.kpno.noao.edu> <obs24m@mdm.kpno.noao.edu> wrote:<br class=""><br class="">MDM Trouble Report for 2016 May 09<br class=""><br class="">Telescope: 2.4m<br class="">Observer(s): Zhijie Qu (University of Michigan)<br class="">Instrument: OSMOS<br class=""><br class="">Problem(s) Encountered:<br class="">Actually, what's the wrong during the observation, but the obtained images are really strange.<br class="">In many images or imaging flat field, there is a dark region, which I don't know the reason.<br class="">Also, the seeing is good, but there is always strange tails around bright stars in Halpha band.<br class=""><br class="">------------------------------<br class=""><br class="">Submitted on 2016 May 10 [4:31:39]<br class=""><br class="">Observer Contact Email: quzhijie@umich.edu<br class="">(Note: thiswill not appear in versions of the trouble report archived online)<br class="">_______________________________________________<br class="">ASTRO-mdm-trouble mailing list<br class="">ASTRO-mdm-trouble@lists.osu.edu<br class="">https://lists.osu.edu/mailman/listinfo/astro-mdm-trouble<br class=""></blockquote><br class=""></blockquote><br class="">_______________________________________________<br class="">ASTRO-mdm-trouble mailing list<br class="">ASTRO-mdm-trouble@lists.osu.edu<br class="">https://lists.osu.edu/mailman/listinfo/astro-mdm-trouble<br class=""></blockquote><br class="">----<br class="">Dr. R. Mark Wagner<br class="">Instrumentation Scientist and Head of Science Operations<br class="">Large Binocular Telescope Observatory/The Ohio State University<br class="">933 North Cherry Avenue, Tucson, AZ 85721<br class="">URL: http://vela.tucson.lbto.org/~rmw/ Email:mwagner@lbto.org<br class="">Phone: (520) 626-3006 <span class="Apple-tab-span" style="white-space:pre"> </span><span class="Apple-tab-span" style="white-space:pre"> </span><span class="Apple-tab-span" style="white-space:pre"> </span> Fax: (520) 626-9333<br class=""><br class=""><br class=""><br class=""><br class=""></div></div></blockquote></div><br class=""></div></body></html>