OUTSTANDING JOBS ACTION LIST ============================== priority: 1-3 #12 DATE: 15/5/93 PRIORITY: 3 Check efficiency of 2-nd order light with 1200 grating in blue in relation to that of the 2400 holographic grating which is inefficient below 4000 A. Let Robin Clegg know. STATUS: RESULT: - #47 DATE: 30/8/93 PRIORITY: 2 STATUS: re-focussing the TV causes the image to change position. May be that the focus drive is skew, or something is mis-alligned. One option is that the TV mirror is misalligned after the quick-and-dirty job 3 months ago. Also the TV focus is near one end of it's travel, which should be re-adjusted. Contact Sue W. for good re-allignement job. 7/11/94 still not been solved; work ongoing. RESULT: - #51 DATE: 1/8/93 PRIORITY: 3 guiding is usually suspended while doing arc exposures during observing. Maybe this can be improved by extra baffling in the A&G STATUS: 1/8/93: Sue looking into this RESULT: - #52 DATE: 26/10/93 PRIORITY: 2 whole of A&G box needs to be re-alligned by some optics expert ! STATUS: 8/11/93: talked with Sue Worswick who agrees. There should be an opportunity during one of the stand-downs next year. See #47. 7/11/94: did not happen semester 94b; now trying to have it done in semester 95a. RESULT: - #56 DATE: 9/11/93 PRIORITY: 3 get large quarter wave plate. There is not really a strong scientific case for this since most objects for circular pol. measurements are point sources anyway. STATUS: - RESULT: - #57 DATE: 9/11/93 PRIORITY: 1 investigate possibility of improving response of Deuterium lamp, or get any other kind of blue flat field lamp. STATUS: 1/11/95: Dave King will do experiments to see what lamp might produce good blue flats. RESULT: - #60 DATE: 19/12/93 PRIORITY: 2 measure which gratings have power by getting optimal focus for all gratings. A systematic difference between gratings will help keeping ISIS in optimal focus. STATUS: 6/5/95: wait for ISIS servicing to be ready, then re-establish *all* optimal focus values. RESULT: - #62 DATE: 15/2/94 PRIORITY: 2 blue grating positioning is off. STATUS: 15/2/94: improved, but still not what it used to be. There now is an offset of +35 to the cenwave command to get the correct wavelength centered (that is with the 300 grating). RESULT: - #63 DATE: 15/2/94 PRIORITY: 2 TV image shows flexure of a few (~2 arcseconds, ~10 pixels) which may be responsible for the somewhat poor calibrate results lately. STATUS: 29/6/94: this has been thoroughly investigated and indeed the TV probe was found to be flexing. This problem probably has always been there. There is a plan to construct an end-stop which would hold the probe in place to prevent is from flexing 26/1/95: still under investigation. 1/11/95: Cass A&G box has again thouroughly been looked at; the TV probe has been tightened, but the effect on the sky now appears worse than before. Continue investigating problem. RESULT: - #68 DATE: 12/4/94 PRIORITY: 2 ghosts have been reported with the new dichroics. Investigate what is the cause. STATUS: 12/4/94: images were taken with the narrow dekker and the tungsten lamp. For fixed wavelengths in the read and the blue arm, using the 600 gratings, spectra were taken through the different dichroics and mirrors. Main results are listed elsewhere in detail. Stray light is getting into the blue arm with the dichroic, most likely through reflections off the mirror next to the dichroic. Possibly a baffle just above the dichroic slide which only admits light going through the relevant path may reduce this problem. This must be tested. RESULT: - #71 DATE: 11/5/94 PRIORITY: 2 have facility to store TV images STATUS: 1/12/95: Stuart Barker looking into the general problem of storing TV images, also for the purpose of measuring QE and S/N on the TV systems for development of CCD based TV systems. RESULT: - #72 DATE: 11/5/94 PRIORITY: 2 have facility to store autoguider output STATUS: 7/11/94: Bruce Gentles managed to get autoguider images into IRAF format on the Sparc station. This has to be documented and tested so we can release it as an option to observers. RESULT: - #73 DATE: 11/5/94 PRIORITY: 2 link GSS output to TCS and ICL so that probe coordinates don't have to be typed in. STATUS: 7/11/94: Robert Laing working on this. In pre-release version it had been proven to work. RESULT: - #79 DATE: 1/6/94 PRIORITY: 2 We need a good ThAr lamp which is bright enough to be useful. STATUS: 6/5/95: ThAr may have too many lines to be of general use with ISIS. Investigate other arc lamps. RESULT: - #81 DATE: 12/8/94 PRIORITY: 2 it is found that the 6100 dichroic degrades the image quality in the spatial direction. A narrow dekker (1.2") profile without the dichroic results in a ~square spatial profile of ~4 pixels wide, while through the dichroic the profile degrades to a somewhat triangular shape with ~8 pixels base width. Note that the degrading in the spectral direction was hardly noticable (no focussing was attempted; collimator position was 5200, so close to nominal). This was found at 8200 A with the R1200R grating and the EEV CCD on the red arm. This needs to be checked at other wavelengths, with another grating, and with the other dichroics. STATUS: RESULT: #82 DATE: 10/11/94 PRIORITY: 2 Tom Marsh reports: The blue arm has some really terrible features in the flat field. Some of them are clearly internal reflections which do not affect the data and thus make the data worse. There are some other which are curved and run almost but not quite parallel to the slit. These features are really bad, as much as 20% in fact, and for example I think they have ruined the Hgamma absorption line in the data. These may have been because no dekker was in place, but perhaps that should be made standard practice or something. Feel free to pass this onto whoever is in charge of ISIS. The red arm flats have a very unpleasant cusp. These really need to be cleared up I think, the setup was 5700 dichroic, R600B grating, cenwave=4597 There is a most unpleasant reflection and unfortunately the object is slap bang in the middle of it. there also appear to be 10 - 15 % variations which run all across the chip. these things are all on hgamma. worse, there were 2 nights of data with different formats and this ultimately means that the hgamma cannot be used at all for radial velocities as its breadth is very similar to the flat field features. STATUS: 6/5/95: this awaits finishing of the servicing and re-alignment of ISIS. RESULT: 15/1/95: the curved reflection Tom mentiones is a feature which was introduced after the ISIS refurbishing last summer. Test so far suggest that it is only there when the dome lights are on, and thus should not affect the data when dome lights are off. The other effects need more checking out. #84 DATE: 25/1/95 PRIORITY: 2 we need red supression filters for both the red and blue arm of ISIS in order to get more balanced flat field with Tungsten lamp. Also blue cutoff filters for the blue arm are required. Finally an ND1.0 filter for blue and red arm would be useful. STATUS: 25/1/95: ordered with Dave King: for the RED arm of ISIS: GG395, BG28, BG39 and ND1.0 size: 35.0 by 80.0 mm (tolerance 0.1 mm) for the BLUE arm of ISIS: BG28, ND1.0, GG495, RG630 and OG550 size: 27.9 by 80.0 mm (tolerance 0.1 mm) RESULT: #87 DATE: 22/2/95 PRIORITY: 1 acquire second small feed, silver coated, to replace the large feed flat for WHIRCAM work on AUX port. STATUS: 6/5/95: this is now a genuine RGO project. Push for progress... RESULT: #88 DATE: 4/4/95 PRIORITY: 2 measure the actual spectral range convered for each grating, and check whether it varies with wavelength. It appears that the values listed in the manual are slightly too large. STATUS: RESULT: #89 DATE: 4/4/95 PRIORITY: 2 update ISIS manuals and guide. Get things right regarding cross disperser, fibres, polarimetry, dichroics, throughput, multi-masks, etc. STATUS: RESULT: #90 DATE: 4/4/95 PRIORITY: 2 update ISIS polarisation manual. Improve readibility and include imaging polarimetry STATUS: RESULT: #91 DATE: 6/5/95 PRIORITY: 1 improve the way the dichroic filters are mounted. Currently they are held in place poorly by metal clamps which may work loose, introducing serious flexure. STATUS: RESULT: #95 DATE: 6/5/95 PRIORITY: 1 investigate possible improvements of ISIS structural flexure. STATUS: 6/5/95: Spoken to Sue W about this. She thinks there is scope for improving flexure. In the design phase the limits on weight and off-axis moments for the Cass rotator were tight. Now they are more relaxed and we could look into improving the structural stiffness. This needs some careful mechanical analysis. RESULT: #96 DATE: 15/1/96 PRIORITY: 1 Vik wrote: Every evening I check the focus with isis_focus and every evening it changes by up to 1000 collimator units! Having started the run at the optimal collimator setting three nights ago I am not at very close to the upper limit of the allowed range. Do you know why this might be happening? I don't think it is due to people touching the system since it is the weekend and the system has been left exactly as I left it. What I have been doing every afternoon is taking the system down and then bringing it back up again immediately. Perhaps this moves collimator slightly (it never used to). I don't think the problem is temperature fluctuations either. Very strange, STATUS: RESULT: #97 DATE: 14/1/96 PRIORITY: 2 measure the actual polarisation through the polaroids in the A&G box over the full spectral range, up to 1 micron. Do this for the polaroids, but also for the calcite in the main filter slide. Aim is to document the exact reange of which the can be used as efficient polarizers STATUS: RESULT: #99 DATE: 1/6/97 PRIORITY: 1 anecdotal reports on astigmatism of ISIS. Check optimal collimator position STATUS: 1/7/97: checked auto-collimation position on both arms. Optimal values have not changed substantially since servicing and realignment of ISIS in 1995. RESULT: released #100 DATE: 6/5/95 PRIORITY: 1 STATUS: RESULT: =========================================================================