IMACS progress report no. 44 B. Bigelow 10 December 2001 Project Status Currently scheduled tasks: Status: a) DSS redesign (Hare) IP b) DSS drafting (Cleary) IP c) DSS fabrication (Kowal, Castillo) IP d) Calibration system mech. des. (Hare) IP e) Coll. opto-mech assembly (Bigelow) re-started f) Long camera opto-mech assembly (Bigelow) re-started g) Principal Guider Camera elec. assy (Asa) on sched. h) Science Array controller fab (Burley) 95% compl. i) Short Camera drafting (Cleary) done j) Filter procurement (Sutin) IP k) Grism procurement (Sutin) IP l) Motion control electronics design (Carr) 95% compl. m) MC fab. (Asa) 50% compl. n) Control software design (Birk) on sched. o) Instrument structure design (Gunnels) on sched. p) Instrument carriage design (Gunnels) on sched. Project events in November: - Coated optics for Long Camera and Collimator are complete! - Instrument structure fabrication progressing rapidly - New quotes for asphere fabrication - First short camera optic finished and delivered Latest construction images can be seen on the IMACS web site: http://www.ociw.edu/instrumentation/imacs See the latest images of: Collimator lens and cell assembly Instrument structure Optics (Sutin) 1) Short camera spherical lenses: S02 is delivered. There is a big crystal boundary in S05. This is not unusual, and if we are lucky, it will never make any difference. 2) Short camera aspheres: We received responses to our RFQ from Danbury and Tinsley, and a response for one of the two lenses from SAGEM/REOSC. Including the previous quote from Lick/Burge, we have four possible vendors. The Tinsley and Lick/Burge quotes are similar in cost and about half the cost of the other two quotes. We are assuming that Tinsley is the most likely possibility at this time. SORL did not respond to the RFQ. 3) Spectrum TF coated the remaining collimator lenses and all of the long camera lenses. All the lenses are now here at OCIW. The reflectivity was generally better than 1%, but I have not computed an average yet. 4) The L05 CaF2 element has a strange pattern of marks on the more curved side. We suspect that the pattern is deep subsurface damage created during generation which was not completely removed during figuring. The pattern was not visible until the coating was applied. The pattern could be ground off and the surface re-figured and re-coated. We are currently reluctant to do so, largely because of the risk of breakage of a difficult- to-replace CaF2 element. 5) Barr decided, after telling us the were on time, that the BVRI filters would be three months late. The major impact of this is that I have no idea where to order the Sloan filters from. 6) The grism substrate material has been ordered for a 200 l/mm, a 300 l/mm, and a 600 l/mm grism. The optimal glass for the 600 l/mm grism was not available, but Ohara suggested an alternative material, which we ordered. The transmission at 3900A will not be great. 7) Paul C, after replacing half of the hardware on the IMACS guider PC, installed Linux 6.2, and then Greg Burley installed his guider software. The guider PC is now functional. 8) The CF guider slit-viewer magnification is slightly off. We have to check the Shack-hartman focus first, which requires a decent point-source illuminator. Joe is putting together the power supply for that. 9) The lens-protectant coating which we purchased is such a deadly heath hazard that we have decided to dispose of it. We are exploring other materials. Electronics (Asa/Carr) Asa: Accomplished in November: Spec'ed and ordered parts for Dave's new schematics. Filter server crates will be built by the wood shop early January. Completed design of Dewar Focus Limits mechanism. Completed testing of Slit Mask transfer mechanism. Wired Principle Guider Camera. To Accomplish in December: Wire Shack Hartman Guide Camera. Fit new computer in chassis. Wire Grating Tilt Mechanism. Software (Birk/Clardy) - I had a meeting with Alan Dressler and John Mulchaey about the design and functionality of the user interface. I spent most of my time for IMACS this month implementing the ideas and improving the graphical status display for the instrument. - After some small adjustments I ran Filter-server-II for about 2 hours continuously (horizontal moves). No problems showed up. I will conduct two more tests: 1) move the tray at 45 degrees and 2) inserting the filter vertically. For December I plan to finish the tests with filter-server II, continue on DSP/science array software, and start testing the PR-guider. Detector Systems (Thomson/Burley) Last month, we started profiling with two of the SITe CCDs. Two chips were adjusted for height and tilt to make a matched pair. The mean height of their three support points agreed to within one micron, and the peak-to-valley tilt over the three support points is better than three microns for each chip. Next comes the alignment of the two chips on their supports for rotation and offset, this will happen early in December. Tests were made with the double-correlated sampling time on the guider cameras. The read noise for the camera drops to about 5.5 electrons for an integration time of as short as 2.5 microseconds (a readout time for the SITe science chips of approximately 70 seconds). This indicates that the recent problem we have been having getting low read noise values for the SITe chips with this readout time does not arise in the electronics. We are considering mounting one of the Marconi guider chips in the lab science test dewar to confirm this conclusion. In the shop, we have some mounting holes and slots being machined into the electronics boxes for the IMACS, MIKE and 4Kx4K cameras -- these are expected to be finished this week. Wiring of the electronics boxes will start as soon as the boxes have been plated. The updated linux device driver (for kernel 2.4.x) has been tested, as has the optical link (in a loop-back test). Work continues on revising the dsp board, and we are waiting for the clock driver blank boards to arrive. All of the preamp boards, and the single-chip and array backplanes have been assembled for the IMACS, MIKE and 4Kx4K cameras. Mechanics (Bigelow/Hare) Bigelow: In November: 1) Re-started collimator opto-mechanics assembly 2) Completed long camera baffle designs, ready for fab. RFQ 3) Finished short camera drafting, received fab quote from M&T 4) Revised CFG and LCAM aperture frames and masks, drawings are in the shop 5) Mask server shuttle was anodized and re-assembled 6) Mask server transfer base plate fab. started at M&T For December: 1) Finish collimator assembly 2) Start long camera opto-mech assembly 3) Order long camera baffles 4) Continue transfer of Gunnels 2D structure designs into MD5 5) Final assembly of mask transfer system Hare: Current Work * Minor rework and redesign of miscellaneous guide camera hardware. * Testing Center Field Guide Camera. * Assembling mechanical components of the Shack-Hartmann Guide Camera in preparation for electronics work. * Review of the design of the Clamp/Latch Assembly, Wheel Assembly, Main DSS Support Assembly, and the Cable Wrap Assembly has been completed and appropriate revisions have been completed. * Clamp/Latch Assembly fabrication is in progress. Future Work * Continue assembly, testing, and rework of all guide cameras as necessary. * Begin fabrication of Wheel Assembly, Main DSS Support Assembly, Cable Wrap Assembly, and Taper Pin Assembly. * Make revisions to solid models and part drawings of the DSS Main Drive Assembly as needed. * Assemble one Grating Tilt Mechanism for testing. * Order necessary outstanding DSS parts. * Test mechanics of the Principal Guide Camera. * Design and build tooling to mount the Field Lens into its cell. * Fabrication of the second shutter. * Resume design work of the Calibration Unit. Fabrication (Kowal/Storts/Castillo/Ramirez) Kowal: November's Report: 1) Clamp Mechanism is in progress...75% finished. 2) Revised brackets were made for Shack-Hartmann Guider. 3) Produced and modified various parts for guiders. 4) Slit Mask Server was anodized. Expectation for December: Two weeks of Dec. that is! 1) Finish DSS Clamp Mechanism 8) Other Business Next meeting: 10:15, 1/9/2002