Re: [Utah-astronomy] My new solar mount setup
Chuck, one thing to look out for is the computer alignment. The newer Celestron's include the "Sun" as a valid solar system alignment target for daytime use. I can't speak for the newer Meade stuff, but on the three year old ETX that I picked up, the "Sun" is not a valid daytime solar system alignment target. I also consider the GT114 mount about as low as you can go in the Celestron catalogue. Hope that helps. - Kurt
Good to know. Kind of makes you wonder about GoTo mounts that can't be initialized using the sun, yet offer the solar tracking rate. On Wed, Jun 10, 2009 at 3:41 PM, Canopus56 <canopus56@yahoo.com> wrote:
Chuck, one thing to look out for is the computer alignment. The newer Celestron's include the "Sun" as a valid solar system alignment target for daytime use. I can't speak for the newer Meade stuff, but on the three year old ETX that I picked up, the "Sun" is not a valid daytime solar system alignment target. I also consider the GT114 mount about as low as you can go in the Celestron catalogue. Hope that helps. - Kurt
Unless you are going to look at other objects, like Venus, is there any reason to have goto on a solar mount? A PST for instance can only be used to view the Sun.
Good to know. Kind of makes you wonder about GoTo mounts that can't be
initialized using the sun, yet offer the solar tracking rate.
On Wed, Jun 10, 2009 at 3:41 PM, Canopus56 <canopus56@yahoo.com> wrote:
Chuck, one thing to look out for is the computer alignment. The newer Celestron's include the "Sun" as a valid solar system alignment target for daytime use. I can't speak for the newer Meade stuff, but on the three year old ETX that I picked up, the "Sun" is not a valid daytime solar system alignment target. I also consider the GT114 mount about as low as you can go in the Celestron catalogue. Hope that helps. - Kurt
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I don't think the manufacturer makes you sign a paper stating that you will ONLY use the mount during the day with a PST, lol. GoTo with the capability to initialize using the sun allows tracking during the day. There are no other visible stars to use for alignment. For a portable set-up, this is important, especially when away from a street grid aligned with the compass points, where you could get "close enought" with a non-goto equatorial for short tracking runs. It's just a convenience, Erik. Kurt pointed out that tracking allows more relaxed solar viewing. GoTo makes alignment a snap in daytime. And, of course it could easily be used at night with a conventional telescope attached. On Thu, Jun 11, 2009 at 10:09 AM, <erikhansen@thebluezone.net> wrote:
Unless you are going to look at other objects, like Venus, is there any reason to have goto on a solar mount? A PST for instance can only be used to view the Sun.
Kurt , does your own PST display ghost images near the edge of the FOV? Did you buy yours new, or used?
I've been looking at the Orion Tele Track mount as fairly attractive for mounting my PST. However, it does not have the sun in it's database as an alignment object. Here is the reply from Orion tech personnel, to my question of using the sun as an alignment object: *"Dear Chuck: Thank you for contacting Orion. We have customers who have said they have use a PST on the TeleTrack GoTo mount. They aligned on an object near the sun and then used the controller to slew the scope to the sun by hand. I believe that the TeleTrack would be tracking at sidereal rate and not solar rate. The sun is not an alignment object."* Ok, ok, an object near the sun? That means what, Venus or the moon? And if neither is near the sun? But then this solution occured to me, and it's an absurdly easy work-around for no sun in your alignment object database: *Using your planetarium software, or just some careful plotting on your paper atlas, find an object in the database that the sun is currently either very near, or actually in front of. Then just aim at the sun manually and tell the GoTo that you are syncing on that object. * ** The lack of a solar tracking rate shouldn't be a problem for low and medium power visual solar viewing, or even the type of imaging we are likely to do with the PST.
Now I'm wondering if my procedure is what the Orion tech tried to convey, and I mis-understood. It's just too easy.
I guess one could try to use the PST at night or look at Venus, I would not guarantee a person would see anything.
My thought was that unless you have accurate polar alignment don't you need to align on more than one star? So tracking would still depend on accurate polar alignment. When I took the SLAS solar scope to events, using my G-11, I did not need to make a lot of corrections. I usually only needed to adjust scope when someone bumped it. I don't think the manufacturer makes you sign a paper stating that you
will ONLY use the mount during the day with a PST, lol.
GoTo with the capability to initialize using the sun allows tracking during the day. There are no other visible stars to use for alignment. For a portable set-up, this is important, especially when away from a street grid aligned with the compass points, where you could get "close enought" with a non-goto equatorial for short tracking runs.
It's just a convenience, Erik. Kurt pointed out that tracking allows more relaxed solar viewing. GoTo makes alignment a snap in daytime. And, of course it could easily be used at night with a conventional telescope attached.
On Thu, Jun 11, 2009 at 10:09 AM, <erikhansen@thebluezone.net> wrote:
Unless you are going to look at other objects, like Venus, is there any reason to have goto on a solar mount? A PST for instance can only be used to view the Sun.
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Erik, the mounts we are talking about are *alt-az,* computer-controlled GoTo mounts. There is no polar alignment, and they track by driving both axes. The PST is a dedicated, H-a solar telescope and can be used for nothing else. On Thu, Jun 11, 2009 at 3:05 PM, <erikhansen@thebluezone.net> wrote:
I guess one could try to use the PST at night or look at Venus, I would not guarantee a person would see anything.
My thought was that unless you have accurate polar alignment don't you need to align on more than one star? So tracking would still depend on accurate polar alignment. When I took the SLAS solar scope to events, using my G-11, I did not need to make a lot of corrections. I usually only needed to adjust scope when someone bumped it.
I want to re-emphasize the gist of Kurt's original post. These small, inexpensive, alt-az GoTo mounts are ideal for casual solar viewing, with the added bonus of tracking which makes higher magnification views much more relaxed and less finicky. See the photos Kurt posted of his set-up on his gallery page. The right-angle design of the PST makes it perfect for use with a single-arm alt-az "upswing" mount. The lack of a polar axis makes alignment an easier procedure in daytime. Kurt's warning about some mounts not having the sun in their alignment object database isn't a concern if you select an object that is reasonably close to the sun (even though it's not directly visible in daylight) and just tell the mount that you are centered on it when you are really centered on the sun itself. Balance isn't quite as critical with these mounts as with equatorials, either. My goal is to mount my PST *and* my home-made 50mm f/9 white-light (Baader filter) solar telescope side-by-side on the same mount. Thanks again to Kurt for putting his setup together and posting, and Bill Cowles indirectly for sowing the seeds. I was originally going to use a small GEM but the more I looked at this option, the more it made sense. And the mount can be used at night, too.
I've got to make one of these. The eyepiece holes aren't really needed, but the idea is great for the PST, or even white-light solar telescopes: http://www.scopesnskies.com/magnify/1392.3.html
Where's the cup holder?
I've got to make one of these. The eyepiece holes aren't really needed,
but the idea is great for the PST, or even white-light solar telescopes:
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Lol. Erik, you'd have to make it pivot so as the sun changed altitude, you wouldn't spill your beverage. Seriously though, solar viewing can be a difficult, sweaty activity. Some of us made similar sun-shields for our filter-equipped parallelogram-mounted binoculars for partial solar eclipses and general white-light viewing. With straight-through binos, this is a necessity since you are facing the bright sun while trying to peer through the eyepieces. I remember Dave Dunn posted about his version. H-a observing is tough because the image is dim, and in the case of the PST, with a small primary aperture as well as a constricted aperture opening at the focal plane, the telescope's aim is critical. The "sweet spot" is dead-center and you can't really let the sun drift across the field of view. It's very narrow and the sun must be kept fairly well-centered all the time. The final handicap is that our own pupils are about as small as they can get when out in bright sunlight, so we have to get our eye positioned exactly right at the solar telescope eyepiece. I'm thinking of some kind of large PVC-framed sunshade covered with an opaque tarp, and a small hole to poke the barrel of the solar telescope through. Keep the entire observer in the shade. Using the electronic eyepiece and a TV monitor is another option, but not nearly as desireable as actually looking through the eyepiece. Either that, or the "Sombrero PST Mount"... *;o)* Solar observing is at least less sweaty in winter time. I had a few minutes with the PST this morning before the clouds drifted-in, and the sun is still one quiet star, folks. On Sun, Jun 14, 2009 at 9:10 AM, <erikhansen@thebluezone.net> wrote:
Where's the cup holder?
Aloha Chuck my solution to the solar viewing problem has been to put a 'gobo' (go between, a 12x18 piece of matt board that's white on one side, black on the other clamped to a pole) to shade the person and eyepiece and to put a circular disc of thin plastic ( Old G11 clutch pads are perfect) w/ a layer of black velveteen glued on. The gobo blocks the sun from heating you up and looking into the eyepiece w/ a black field around it is easy on the eyes. I use this set up on my refractor w/ a Herschel wedge, we'll do a similar set up when the Lunt LS200 arrives. All we need now is something that is interesting on the sun. Aloha Rob
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Rob Ratkowski Photography