24" Replacement Project - Proposal
Introduction
The following document outlines the details of the proposal to replace the current 24” scope in the main dome with a more modern and accessible telescope. It covers the requirements for a new scope, proposed equipment and the rationale for the project.
The new telescope will allow the Hamilton Astronomical Society to:
Offer a better viewing experience to the public
Offer a better experience to school and community groups
Take great images of the sky which would be used to promote the society and educate the community
Improve the accessibility of the current dome configuration making it easier for more people to see the sky at a higher throughput
Provide a solid foundation for expanding the societies scope and reach into the Waikato community
Conduct limited research and contribute to astronomical knowledge
The committee and member base are working hard to expand the membership, community outreach and capabilities of the society. We aspire to provide the Waikato with a great experience and to provide public engagement and education to as many people as possible.
This proposal has been carefully considered. As much detail as possible has been provided to help our funding sources understand the project and what we hope to achieve with the funding provided. This proposal has already been submitted to the societies member base and we have collected their feedback to contribute to this document.
The society is open to questions, comments and suggested amends regarding this proposal. You can provide feedback on the proposal through the form below.
What’s wrong with the current telescope?
While the current 24” has served the society well it has several issues that have spurred the society to seek funding for a more modern replacement:
The optics of the 24” are of low quality and provide only fuzzy small images of solar system and deep field objects.
The 24” has no capability for imaging.
Using the drive and pointing system for the 24” is complex and inaccessible for members.
The 24” is so difficult to use it is often not used in favor of smaller telescopes.
The structure of the telescope is deteriorating; the fiberglass it is made of is delaminating and falling apart
The computers running the motors are so old that they can not be replaced owing to their parts no longer being made
The 24” has a massive footprint compared to modern scopes reducing the space in the dome for visitors and members.
The planned replacement telescope has a mirror that is 7” smaller than the existing telescope. However the new scope will still be able to provide sharper and clearer images than the existing scope due to it’s more modern design and superior optics
Equipment required:
The society has compiled a list of equipment that will be required to upgrade the dome with a modern scope. This list includes not only the scope itself but the elements required to install it and operate it successfully.
The equipment listed has been vetted by multiple members of the society and experts in the field. We have selected the equipment below to provide the best balance between technology that will meet the following criteria:
Good viewing for a wide range of objects
Suitable for educational purposes
Easy to use to make it accessible to all members
Priced at a level where funding is achievable in the short term
Can be installed quickly with minimal support
Robust and easy to maintain
Allows limited research and investigations
Provides for limited astro photography
Expandable and upgrade-able in the future
Below is a list of the chosen equipment with a brief description of each item, why it is required and how it relates to the wider project:
Optical Tube Assembly
Planewave 17” Corrected Dall-Kirkham (CDK) OTA
The Optical Tube Assembly or “OTA” contains the mirrors required to focus the light through the eyepiece. We have chosen a CDK configuration, it offers excellent image quality at an affordable price, it is versatile for viewing a wide range of objects. The selected model is also light so as not to overload the dome pier, simple to use and most importantly robust.
http://planewave.com/products-page/telescopes/17-inch-cdk-optical-tube-assembly/
Mount
Planewave L-500 Direct Drive Mount - (Altazimuth Configuration)
As or even more important than the OTA is the mount that the OTA sits on. A good mount is critical to be able to accurately and reliably steer the telescope. A computer controlled “Go To” mount provides tracking at the press of the button increasing the accessibility of the instrument. The chosen mount also allows for expansion of the OTA in the future if needed. This mount also comes packaged with the software required to drive it.
Camera
CCD Sensor Camera - STXL-11002
This camera will serve 2 purposes, firstly it allows us to align the telescope using known star locations, this will mean that the mount is able to precision calibrate the position of the OTA. Secondly it will provide imaging capability for the telescope allowing us to capture imagery of objects to use for promotional and educational purposes.
Computer
Intel NUC - Mini Computer
In order to run the software that drives the mount the society will need to replace it’s 80s era controller with a new computer. We’ve chosen a simple NUC for this as it’s sufficiently powered, well priced and has a small footprint. A switch may be required for multiple ethernet IO, this is still being considered.
https://www.pbtech.co.nz/product/BPCINT3431466/Intel-NUC-BOXNUC7i3BNH-Mini-Computer-Kit-i3-7100U
Engineering and installation requirements:
In addition to acquiring the equipment the new scope requires some engineering work to be done to the existing dome. This work is required because the new scope is a different design and requires a different position and height within the dome.
To define the engineering requirements we have / will be consulting with:
The district council - Building consent
Structural engineer - For design and sign off of engineering work
Metal Fabricators - To establish what is involved in the fabrication of the work
Society members
The Hamilton Zoo
The council has been consulted and an agreement that we do not need a resource or building consent has been reached. The work will be staged and the construction planned carefully to ensure that pre-commissioning engineering work is safe, correct and goes smoothly.
The following preparation work is required to prepare the dome for the new telescope:
Clear dome of existing equipment
Dismantle and remove existing telescope
Prepare pier for mounting of adapter
Crane in adapter
Fasten adapter
Safety check and floor repair where needed
Position check for mounting plate
Pricing
Pricing is currently being sought for all of the above components and engineering works, independent estimates are acquired funding will be sought. Information collected so far on pricing has been detailed below and includes some potential additional components :
CDK400 Package A$75,999-00 (contains IRF and EFA - See below)
CDK 17" OTA A$38,999-00
L500 Mount A$30,199-00
IRF 90 (rotating focuser) A$7,099-00
EFA (electronic focuser) A$1,299-00
Additions
Focal Reducer A$1,899-00
Light Shroud A$319-00
Delta T A$1049-00
OTA Counterweight A$319-00
STXL 11002 camera only A$11,399-00
STXL 11002 w/Self Guiding FW8G-STXL Filter Wheel A$15,499-00
STXL 11002 w/ Self-Guiding Filter Wheel Pro Package A$18,899-00
Alternatives
Software Bisque Paramount MEII w/ On Axis Encoders A$37,500-00
Software Bisque Paramount MEII A$27,299-00
STX 16803 A$15,299-00
STX 16802 w/ FW7 STX A$19,999-00
STX Guider A$1,799-00
STX Ultimate Package A$27,599-00 w/ FW7 STX, Self Guider, 50mm Square LRGBC and 50mm Square Narrowband Filter sets
Shipping
Shipping to Hamilton approx A$4,500-00
Dimensions
Shipping dimensions for the above are as follows:
The OTA crate is 150cm X 100cm x 80cm and will weigh 120kg
The L Mount crate is 150cm x 100cm x 80cm and will weigh 150kg
The Camera will be 50cm x 50cm x 50cm and will weigh 30kg
Timelines
Following receipt of funding we estimate the following timelines are required to reach commissioning of the new scope. If at any point we are able to partially fund the project to prepare an item ahead of full funding being obtained then we will do so. Items will be prioritised based on their staging.
Funding round
4-6 months (estimate variable)
Lead time on equipment
8-10 months
Purchase and shipping of equipment
6 weeks
Engineering adapter. In parallel.
4 weeks
Removal of existing scope and preparation of dome
2 weeks
Crane in / out
1 day
Assembly and commissioning
2 weeks
Feedback
Please provide feedback using the form above, all submissions will be considered by the committee and the proposal amended / updated based on member feedback.