As I see it, there are two truths in visual astronomy when it comes to new telescopes:
- Nearly all new telescopes are "amazing" and "wonderful". My 20" f/3 Spica Eyes Dob with optics from Mike Lockwood was no exception. Heck, my 60mm Jason refractor that I bought as a teenager in the mid-eighties was the same way. There's nothing like a new telescope.
- All telescopes have a "personality". As a telescope gets used, you learn its strengths and weaknesses. You find things that you enjoyed that you didn't expect, and you learn to correct or compensate for any of its peculiarities that will undoubtedly surface with repeated use. And again, the Spica Eyes Dob is no exception.
I've had the telescope for about 18 months now and I've been able to put it to pretty large amounts of use in that time. I thought it would be useful to post a follow up report on the telescope now that I have a broad range of experience with it. It's been nearly all good, and a few tweaks of the telescope in that time. For the backstory on this instrument, I posted a First Light Report in July 2019 that can be found here.
My original goal was to have the largest aperture, premium dobsonian that could be built with native tracking that didn't require a ladder or wheelbarrow handles and could fit into the backseat of GMC truck. I thought I had exactly that 18 months ago when I took delivery of the scope. And today, it remains true. The telescope has continued to perform at a top level every time that I've had it out since then.
- Quality Construction: It's still built like a tank. The starting point of the laser beam for collimation has landed somewhere inside the circle of the CatsEye hotspot every single time. Once collimated, the telescope holds collimation until its torn down for the return trip to home.
- Fast cool down: I run the rear cooling fan all night long, and I point a small box fan at the primary during twilight to aid in cool down. The 1.25" thick optics are near equilibrium by the end of twilight and do an excellent job of remaining close to ambient temperature all night long. The biggest benefit of this is being able to use higher power than I'd previously thought possible pretty much all the time.
- It's quiet: The cooling fan is inaudible at the eyepiece. It's possible to hear the motor on the tracking platform, but you have to listen for it. No whirring of motors, no fussing with cables. While this doesn't actually make the telescope perform any better, it's a great benefit to the overall observing experience. The only time the telescope intrudes on the observing experience is to stop and reset the tracking platform every 80 minutes.
- It's a strong performer on nearly all objects. I'm convinced that there's nothing that a large aperture, well made, well collimated and ambient cooled optic doesn't do well. On my last 8 day observing trip I hit a broad range of targets, and the scope excelled:
- At 475x, Mars feels as big as the moon just like those emails have been promising for years.
- Inspired and encouraged by fellow CN'er Allan Wade - Phobos, Deimos, Ariel, Umbriel, Titania and Oberon were checked off my planetary satellites observing list.
- I spent a couple of hours teasing out and confirming NGC and IC objects in M33.
- Globular clusters at high power are just ridiculous assaults on my eyeball. This trip included confirmed observations of Pease 1 within M15.
- There's nowhere in the 2.5º space between the eastern and western Veil nebula that doesn't contain nebulosity.
- It was a joy to chase down and track near earth asteroid 1999 AP10 on October 17th for over an hour.
This isn't to say that the telescope has been perfect, because it hasn't. As I've learned its personality there have been a few things I've had to learn to manage and a few things I've changed. None of them detract from the enjoyment of the scope or make me wish that I'd made a different decision.
- Low altitude objects are really low. Viewing Omega Centauri and other far southerly objects will have you near sitting on the ground or kneeling into the eyepiece. It's a pretty simple workaround to reset the EQ platform right before these observations as doing so will angle they eyepiece upward, making for more comfortable observing.
- I've wrestled with stiction. I've learned to keep the teflon clean and to soap the bearings occasionally as a solution. But early on, I had some issues with stiction, especially in azimuth. I'm probably also jaded coming from an Obsession Classic as my previous scope. There's nothing more buttery smooth than that telescope.
- The shroud continues to teach me patience. The light shroud fits the telescope so tightly that it's a process to get it onto the scope and pulled down into position. Since it only happens once it's a minor quibble...but it could have been just a *touch* looser fitting.
- The cooling fan and platform batteries have died. This is certainly from user neglect. The 3ah battery for the cooling fan and the 9ah battery that powers the platform no longer hold a charge. I've replaced them with more easily removable and rechargable 3ah lithium ion batteries. If one battery dies, I just swap it out in about 30 seconds with a freshly charged one, and put the other on a charger in the RV. This change in batteries has also had the benefit of eliminating about 9 pounds of total weight from the scope.
- I've never used the 'controller' on the EQ platform. Normally, I just power it up and push it underneatht the telescope out of the way so it can do its job. As part of the battery replacement project, I semi-permanently mounted the EQ platform's electronics to the platform itself, where the old battery used to be located. Here's a shot of the platform's base with 3ah battery and electronics mounted to it.
In conclusion, I had hoped to build a lifetime telescope with this project and I'd like to say that I've succeeded. It has been the perfect telescope for me and has given me nearly zero issues. But if I'm being totally honest, I have to admit that I've caught myself more than once standing at the eyepiece thinking..."I wonder what this would look like with a 30" mirror".
Thanks for reading,
The Animas mountains of New Mexico put on quite a sunset show while waiting for darkness last week near Portal, Arizona.
Edited by Mike Wiles, 22 October 2020 - 05:47 PM.