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Messages - Jim Snyder

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16
Beginners Forum / Re: What is the benefit of joining an Astronomy Club?
« on: January 30, 2018, 11:32:46 PM »
Yep, the hobby is 'graying'. FWIW, I just broached a related idea at our club's monthly board meeting. Based on a casual comment a year ago by one of our younger members, I've suggested that we try a weeknight public stargaze. She once commented that most young folks have uses for weekend nights that are more important to them. I can remember that being true for me, long ago.

So once it gets dark earlier, but before it starts getting uncomfortably cold, I think we'll offer one or more weeknight stargazes, well publicized. There are a few semi-dark place close to town that we can use. Our arrangement with the university even includes the ability to turn the lights out in one remote parking lot with advance notice.

Of course, our club, like some others, has a lot of competition for young peoples' attention. Our area has a busy live music scene, lots of outdoor activities, and a batch of micro-breweries. I think advance (but not by too much) publicity is important to making something like this go over. Local media including websites, the community college and other colleges, and grocery store bulletin boards come to mind.

Jim H.

17
That looks a lot like scans I've seen of the Optolong 25nm 'visual' OIII filter hmm.

With the near 50% transmission of H-beta at 486nm these filters are really almost UHC filters.

They seem to be at reasonable prices for what they are as long as you know what you're buying.

18
I have a 10in f4.66 that will be converted to a dob, and the new carbon fibre 10in f4 will be used as my main deep sky imaging scope and I will also use it viewing rich fields.I do have some coma correctors ,>> the old Lumicon CCFF is attached to my 48mm Lumicon EzyGuider>> a Baader MFCC>> a Tele Vue 2" tuneable top Paracorr ... a recent acquisition>> also have a 2in Tele Vue 2x PowerMate .... a recent acquisitionI'm thinking either Vixen SSW eyepieces (5mm, 10mm, 14mm these are all 1.25in) and maybe NLVW 30mm (2in)orPentax SMC in similar fls 5mm to 15mm as 1.25in eyepieces.I don't mind spending to get very good quality in my eyepieces which will have to do me out , it's taken me years to get to this point.I will likely want to try eyepiece projection once the scope and ROR observatory is installed.Til now my best eyepieces have been RKEs, these may be OK using the Paracorr on the f4.66 dob but I have my doubts about using these even with the Paracorr on the f4.Comments on my eyepiece choices for the f4 Newtonian would be greatly appreciated.

19
Mounts Questions & Expirience / Re: AP Mach 1 or Bisque MyT or Neither?
« on: January 26, 2018, 12:32:11 AM »
Hi Rod,

There is a concerted effort towards simplification in the Software Bisque approach to portable imaging with the LTI interface, Raspberry Pi and "coming soon" automation front-end with Orchestrate. So far it's coming together nicely and is looking like a great way to get up and running quickly while maintaining the comprehensive abilities that the TheSkyX and add on packages offer for more advanced imaging tasks when one would like to expose those elements. If you haven't been playing along at home it's pretty interesting to see how things are developing with the approaches Software Bisque and Astro-Physics over the last year.

While I somewhat agree that a lower tier mount may be suitable for dipping a toe in the water there's something to be said for "buy once, cry once" too.

Clear skies,
Bill

20
Quote
I posted the following on a similar thread back in 2011. I thought I'd share it again.

__________________________________________________________________

Ok, I’ve never told this story in public, so here goes.

This is a story told to me by my Mother in 1979 after I had returned from the Peace Corps. She is 93 now. For a bit of perspective, my Mother is as straight-laced a military wife as they come. Of German decent, she has always been even-keeled and a very strong woman, showing very little emotion about anything when I was growing up. She drank socially, but never at home. She was always healthy and never on any sort of medication. I have a hard time not believing what she told me. She confirmed this story to me again last year. She has never told me any other such stories.

Here’s the story.

Sometime in 1966-67, after dinner, my Dad and I sat down to watch TV and my Mother decided to take a walk around the block. We lived in a new neighborhood in San Antonio, Texas (Castle Hills Terrace) and ours was one of only 3 or 4 houses built in the development at the time of this story.

Some time later (maybe 45 minutes to an hour) my Mother returned. I remember looking away from the TV for just a moment and up to her face as she stood next to us. She was looking distressed, confused and on the verge of saying something, but she didn’t. My Dad and I were involved in our TV show. I looked back to the TV and didn’t think any more of it and neither of us asked her if anything was wrong. She went back to her bedroom and finally came out about some time later, looking perfectly normal and joined us on the couch.

This occurrence was so unnatural for me that it stuck in my head for many years. When I was visiting my folks after returning from the Peace Corps in South America, my Mom and I were chatting about this and that (My Dad wasn’t here with us, but at work) and for some reason that strange night popped into my head and I brought it up.

She immediately said “Oh my, I’ve been holding this in for so long!” She immediately told me why she was acting strange enough that night for me to remember it 13 years later.
As she was out walking, she saw a large flying object approaching her. Her description was of the classic saucer design, but with no lights that she could remember. The object approached closer and stopped a few yards down the street maybe about 50-100 feet in the air. She said it was wide enough to cover the street and half an empty lot on either side. It hovered, making very little noise. After a short time, it lifted and disappeared in a matter of seconds. She has no other memories. When she returned to the house, she was going to tell us, but then thought better of it as she thought we would think her crazy.

What does one make of such a story from a very trusted source?

What was the TV show? It must have been a doozy.

21
Mounts Questions & Expirience / Re: Fornax Lightrack II First light
« on: January 25, 2018, 09:47:31 PM »
Quote
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<p class="citation">StuartJPP, on 22 Jun 2017 - 10:28 PM, said:<a href="https://www.cloudynights.com/index.php?app=forums&amp;module=forums&amp;section=findpost&amp;pid=7953946" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="StuartJPP" data-cid="7953946" data-time="1498163309">That is impressive if you can get &gt;10 minute subs at 300mm on a crop body.

Although I haven't used the Fornax Lightrack myself I have used the AstroTrac. The issue with framing towards NCP and zenith is basically eliminated when using something like the AstroTrac head. Additionally the counterweights help with balance (I was using a large Canon 500mm f/4 L IS lens with mine).

My AstroTrac used to have a fairly well collimated polar scope and I was able to get 3 minute subs at 500mm on a full frame camera. This was before the days of PoleMasters and I really need to get this kit out again and try to polar align the kit properly. I am sure that I could get longer subs with proper polar alignment, though consistent 3 minute subs is probably enough.

Which 300mm lens were you using?

This is what my corners looked like on a Canon 5D Mark III and a Canon 500mm f/4 L IS lens using the AstroTrac.
Hi, StuartJPP, nice image.
i used a nikon AF 300mm F4D lens, the 500mm F4 is too heavy for the Lightrack, the max weight recommended is 6kg, astrotrac can hold 10kg i think. i am using a 1.4X teleconverter to get up to 420mm.
i tried the star adventurer DEC bracket and balance kit today, but it didn't work well i think, the whole system became unstable with all that weight on it. I am going to return the balance kit.
As i think through the problem with field rotation, the only movement i have to compensate is the RA rotation, so, mount the ball head on a panning base will solve the problem, i don't need to make the ball head working as a equatorial mount. this also solves the problem of the interference between the mount and the camera because i can put camera at any position, the only issue is that at some angle the composition may not be optimal. but i think that's acceptable.
The Lightrack II states recommended max telescope weight of 6kg, it isn't quite clear but on a normal EQ mount you don't add the weight of the counterweights to the total. The bearings are most likely able to handle much more weight than 6kg but not if the load isn't distributed evenly. But if you have tried it and it didn't work then that is the acid test and it is best not to push the mount too far. I think the Lightrack II uses friction drive which is different to the leadscrew used on the AstroTrac. The motor on the AstroTrac is absolutely tiny would like to see how the Lightrack drives the tangent arm.

The above image was just a single sub, collect 22 of them and the result is this:

M45 - Pleiades or "Seven Sisters" by Stuart, on Flickr
Very nice image Stuart, i am traveling to long island next month, hope i can get some clear days to pull a few images. the NYC light pollution washed out everything here.


22
General Astronomy & Observing / Re: What to look at during a full moon?
« on: January 25, 2018, 09:00:28 PM »
Only time I enjoy full moon is during total lunar eclipse. Mind blowing experience to see the whole process and faint stars nearby during the totality.

23
Beginners Forum / Re: Doomed newbie
« on: January 25, 2018, 03:42:27 PM »
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As a beginner myself, I've questioned what I want to do for the eclipse (it's going right over my house). After reading a lot of advice, I've decided to just experience it. If I am looking through a scope I will miss a lot of the effects around me and on the people I am with. I'm sure I can get on the forums after and find plenty of great pictures of what it looks like through a scope. I can't get the experience of a solar eclipse from pictures on a forum though. So, no solar film for me except a few cheap viewers.

The partial phases of the eclipse are rather lengthy, giving you plenty of time to observe the Sun with a properly filtered telescope.

If you are near enough to the centerline to see totality, you should definitely look through an unfiltered telescope for at least a short while.

Dave Mitsky

Are you suggesting that he look at the Sun without filter glasses and without a filter on the scope?


That's a rather strange interpretation of what I wrote. The person who I replied to implied that he or she was in the path of totality and I said that if he or she was indeed able to see a total eclipse then he or she should observe it during totality with an unfiltered telescope.

Dave Mitsky

24
unscrew the cw shaft AND the large cap where the cw shaft goes through. even on the CGEM if this cap is on too tight it causes the dec axis to bind (and the CGEM has ball bearings on dec).

25
Light Pollution Topics / Re: Why light pollution will never end
« on: January 25, 2018, 12:46:45 PM »
Honestly speaking, i prefer lighting areas than dark areas even with little lights, the only thing i like darkness for is for astronomy, but i just getting in that this year recently, so if you asked me when i was a kid until i grown up and still not into astronomy then i will vote for lights always.

In addition, why we are trying to force ourselves that all people living in urban are into astronomy or want to do astrophotography? for visual of planets even in bright white zone we can view planets with some scopes, so many won't care about darkness anymore, and even those who want less lights or more of darkness they are looking for relaxation or comfortable environment and not because the sky astronomy, at the end stargazers in most or all population aren't the major, so the government won't listen or go with minor people who are dreaming about dark skies, i even asked my daughters if they want the area all around to be dark so we can see the sky better or have much lights so not good much for sky visual, they chose the latter, it means most minds around me and maybe in the world really care about the lights on earth than brightness of stars.

26
Eyepieces Questions & Recommendations / Re: DeLites are quite good...
« on: January 23, 2018, 07:37:19 PM »
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Too bad we don't have more lab data about eyepieces. Not enough money in the field for such testing, I guess.
I find this a nonsense, companies making and selling eyepieces have all the data in their drawers for sure..

Beside air-to-glass surfaces count and AR coatings "dating" there is no debate about scatter and absorption of light in different types of optical glasses. Light is exponentially attenuated traveling thru glass and it would suffice to say that differences between simple and complex eyepieces are in magnitude 10x or more . Different glasses also absorb different wavelengths by different amount..

27
Mounts Questions & Expirience / Re: Mount aesthetics AP1100 vs AP900
« on: January 23, 2018, 06:07:49 PM »
The Mach1 is indeed pretty and incredibly designed. My favorite mount. The stalk that holds the RA axis to the pier keeps the weight down but is also its weak point. At 60 lbs (over capacity), you can see the difference in vibration east-west versus north-south. If they went to two legs instead of a stalk, I suspect the capacity would be higher.

So I went to the AP1100.

George

28
Eyepieces Questions & Recommendations / Re: Meade 8.8 UWA 5000 versions
« on: January 23, 2018, 04:57:51 PM »
I know this thread is a bit old, but since I recently had the chance to compare both versions of the 8.8mm (Meade 5000 UWA and Meade Instruments 5000 UWA WP), I wanted to report that these eyepieces DO NOT possess the same glass.

Upon closer inspection (see attached photo), the surface shape of the eye lens of both oculars is different. On the Meade 5000 UWA (right in photo), it is flat, or PLANO. But, on the Meade Instruments UWA WP (left in photo), it is curved, or CONCAVE. I also noted that the eye lens opening in the newer MI UWA WP version is slightly larger.

When examining the interior of the newer unit, I found that the flocking was not as good as in the older unit. Finding the flat black paint on the spacer ring in the newer eyepiece was shinier than inside of the older eyepiece.

As for coatings, the older unit is multi-coated and shows green, cyan and magenta reflections, while the new one shows purple and pale-blue.

I also found that even though the older Meade 5000 8.8mm ocular has a smaller diameter body by an eighth to a quarter inch, it seems to be heavier in weight between the two.

Well, I guess at this point, one consolation is that the newer version is waterproof.

My next report will be on their performance...Thanks, MelAttached Thumbnails


29
Beginners Forum / Re: Advice on telescope
« on: January 23, 2018, 04:35:16 PM »
The Porta II's mount arm probably would not accommodate the bulk and moment-arm effect of a 6" f/5 Newtonian. I would have to recommend against it.

Now, the GSO SkyView Deluxe, on the other hand, and just like my own Voyager I, would handle both. Take a look at this...
Note how the mounting-arm is curved, which allows for the 6" f/5 to be centered, and balanced almost directly over the tripod. The GSO is the only one discussed so far that would handle both. I do wish the pier extension was available for it here in the States, but it is available, again, from Australia, and near the end of this listing...

http://www.andrewsco...0-guansheng.htm

...that is, when it's back in stock. It's a very popular add-on. Now, the pier is really only necessary for telescopes with long tubes, like an f/11 or f/15 refractor. It does allow for the 6" f/5 to point a bit further straight up, towards the zenith, but that can also be accomplished by moving the optical-tube forward within its tube-rings, pier or no pier. The refractor, however, may or may not be pointed straight up, in any event. The mount-arm is adjustable, and for different angles, so it may be possible.

Since the AT Voyager I/GSO SkyView can accomodate both, it may be the considered the bulkiest of them all, but it is slightly lighter in weight than the ES Twilight I/AT Voyager II.

I have a collection of smaller refractors, including a 50mm, and I'm looking to get a Vixen Porta II in future, if not the even smaller Mini-Porta; or, an EQ-2 equatorial.


30
Beginners Forum / Re: f/10 vs. f/11 ?
« on: January 23, 2018, 08:49:33 AM »
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<p class="citation">QuoteAndromeda is 7 deg wide...

That's the largest angular size that I've ever seen mentioned.

Careful estimates of its angular diameter, performed with 2-inch binoculars, by the French astronomer Robert Jonckhere in 1952-1953, revealed an extension of 5.2 times 1.1 degrees (reported by Mallas)...

http://messier.seds.org/m/m031.html

What's your source?

Dave Mitsky[/quote]
Just something I heard years ago. Don't remember who or where. Your source indicates a bit under 6 deg. Good to know. Of course a modern telescope or CCD camera could possibly reveal more of andromeda than 50mm binocs.

Scott

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