On Tue, 17 Jun 2003, Magda Arnaboldi wrote: > > Dear Nigel > > we are sending you the email from John Hart where he says what it > is likely to cost the Halpha arm constraction at Stromlo, but it is not > an official quote yet, as he does not know whether they will be allowed > to do it, i.e. we would need the Stromlo director's approval before the > Stromlo workshop can bid for the Halpha arm construction. > > The basic halpha arm constraction with fixed filter costs 27150 au$, > with the filter changes it would cost 44700 au$. > > There are a number of items which are excluded, and our estimate based > on the SNF proposal and partly on old quotes at this stage is 68153 for > the excluded items. We do not have estimated for a couple of those (the > criostat adapters and the control system for the filter) if we estimate > 7000 au$ for those two, we end up to 120000 au$, except for the CCD > system. This looks quite close to what we estimate for the SNF proposal. > > We propose at this stage to ask RSAA for a real quote, to find out what the realities are. > In parallel, we 'd like to pursue with you the possibility of manufacture > at Kapteyn lab because your labor costs of 11 euro x hour is much cheaper than > at RSAA (at least 50 au$). Do you think that Kapteyn workshop would be interested in taking > this on? Would they possibly be interested in having RSAA complete the design work and doing > the fabrication in Groningen? > > Ken is in Groningen next week and free on wednesday afternoon. Would there be any point > for Ken to talk to anyone about this in your absence? > > Cheers > > Magda & Ken > > > -------- Original Message -------- > Subject: from John Hart > Date: Tue, 17 Jun 2003 17:54:14 +1000 (EST) > From: Ken Freeman > To: arnaboldi@to.astro.it > > > > >From hart@mso.anu.edu.au Sun Jun 15 11:00:08 2003 > From: "John Hart" > To: "Ken Freeman" > Cc: "Mike Bessell" , > "Penny Sackett" > Subject: H-alpha Camera Cost Estimate > MIME-Version: 1.0 > > Hi Ken > > I have scoped out the PNS H-alpha camera proposal and done some detailed > cost estimating. As requested, I have considered two options. The first is > to carry through with the originally proposed fixed filter design. The > second is to include two filters that are remotely changeable. Both options > use the optical design produced by Damien Jones in the early days of the > project. > > Fixed Filter Option > > We completed a system design (no detailed design) for the H-alpha camera > while we were designing the PNS some years ago. This was necessary to enable > the possibility of building the H-alpha camera later. The mounting portal > has been included in the PNS, and is currently fitted with a cover plate. > The layout of this system is shown in the attached PDF file. > > In this system, the single filter is mounted within the body of the PNS > camera module by means of screws. It can be changed manually by removing the > beam splitter module that mounts to the portal opposite the H-alpha camera, > and reaching through. The H-alpha camera is cylindrical in shape, and mounts > to the round portal that protrudes from the PNS camera module. The H-alpha > cryostat is not part of the instrument (I believe it is supplied by the host > observatory), but it is shown in generic form. A custom made adapter is used > to mount it on the focuser module that is part of the H-alpha camera. The > focuser module includes tip-tilt adjustability. > > My cost estimate is as follows. > > Filter Cell Design $1100 > Filter Cell Construction $2150 > Barrel Design $1000 > Barrel Construction $4150 > Primary Lens Unit Design $1200 > Primary Lens Unit Construction $1200 > Secondary Lens Unit Design $1500 > Secondary Lens Unit Construction $1500 > Focuser Design Modification $700 > Focuser Construction $7150 > Integration and Test $3500 > Materials and Proprietary Items $2000 > Total $27150 > > Changeable Filter Option > > In response to a request from Nigel Douglas, I have worked out a method of > providing two remotely controlled interchangeable filters in a way that > minimises changes to the original fixed filter design. The circular section > of the barrel is changed to a rectangular section (as was used for the > collimator module of the PNS). Two parallel shafts can then be run between > the side walls of the barrel on opposite sides of the beam, just in front of > the primary lens unit bulkhead. Each is driven by a DC gearmotor, and > carries a filter "flap" that can be rotated through a 90 degree angle. At > one end of this travel, the filter is parked against the side wall of the > barrel, clear of the beam. At the other end of the travel, it is pressed > against a bessel that surrounds the beam, where it is in the deployed > position. The two filters share the same "deployed" location, so either must > be retracted before the other is inserted. > > This system is very similar to that used for both the shutter and the > calibration mask in the collimator module of the PNS, except that here it is > doubled to carry the two filters. > > The existing H-alpha portal in the camera module of the PNS does not > directly suit this barrel configuration, so an adapter plated will be > needed. > > My cost estimate is as follows. > > System Design Modification $3500 > Adapter Plate Design $$550 > Adapter Plate Construction $1100 > Barrel Design $1350 > Barrel Construction $5650 > Filter Changer Design $1750 > Filter Changer Construction $11000 > Primary Lens Unit Design $1200 > Primary Lens Unit Construction $1200 > Secondary Lens Unit Design $1500 > Secondary Lens Unit Construction $1500 > Focuser Design Modification $700 > Focuser Construction $7150 > Integration and Test $3550 > Materials and Proprietary Items $3000 > Total $44700 > > Excluded Costs > > I believe there is a plan to have Damien Jones refine the optical design, > but I have no knowledge of the cost. Presumably, the optical design should > be finished before mechanical design is started. > > I have not estimated the cost of glass purchase or lens construction because > we no longer have an optics workshop, and its re-establishment is uncertain. > Our earlier estimate (Nov 98) for this was $18434. If we undertake > mechanical design, this should include production of the lens drawings > regardless of who is contracted for lens construction. Allowance is made for > this in the above estimates. > > No estimate is included for anti-reflection coatings, but our earlier > estimate (6/12/01) was $7000. > > No estimate is made for the cryostat adapters because the requirement is > unknown. > > No estimate is made for the control system needed to drive the changeable > filters. I assume the control system used for the existing PNS drives would > be adapted, but I have no knowledge of this. > > Comments > > The focuser proposed for the H-alpha camera is the same as the two built for > the main camera, except that minor changes are proposed to the mounting > interface and the preload system (I believe the cryostats used are heavy > enough to overpower the originally provided preload force). Allowance is > made for this in the estimates. > > I believe the estimates provided above are reasonably accurate, but they do > not constitute a quotation. No approval has been given to bid for this work > yet. > > The labour estimates provided above assume a rate of $50 per hour. This is > concessionary, as was the original rate charged for the PNS project ($45 per > hour). If we were to proceed with a quotation, the adopted labour rate would > have to be negotiated with the director. > > Our capacity to undertake this work is dependent on the availability of our > labour resources. We are currently heavily committed to GSAOI, but we could > probably do this extra work within the next year. > > Regards > > John > >