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Messages - engoecircming

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Reflectors Telescopes Forum / Re: Unguided dobs CAN IMAGE planets well
« on: February 09, 2018, 08:58:17 AM »


I looked at the first Saturn image, in the notes he is using a eq platform. So is driven... Try again....

Look at more than one image......the majority are undriven
Hmm, your right. Don't know how he gets that image scale and resolution with his setup and the time to get scope to settle down after moving it and go through all the filters without running into rotational blur on Jupiter. He must be blazing fast!
Just about all of them were done with a color camera without the use of filters for color..... There is a second link in the next message after the image link that shows him taking and processing the images...... But you are right its hard to fathom how he got such fantastic images using the drift method......impressive to say the least

ATM, Optics and DIY Forum / Re: Carbon Fiber Tube Layup
« on: February 09, 2018, 01:31:16 AM »
In the past - I have layed up multiple layers of expensive Carbon Fiber and then had a terrible time getting the card board out even with water.

This time I have a fairly rigid carbon fiber tube that is clean inside and ready inside to use. I have 5 plywood disks on an axle that keep the thin .020" sleeve very round and rigid. I did it this way because I need to make sure that I don't have another accident like last week. I have everything ready to assemble my scope and all that I need is a tube. This seems to be the best way to get it quickly. I may do it differently next time.

Beginners Forum / Re: When do you mark an object as seen?
« on: February 08, 2018, 09:11:12 PM »
After 32 years of writing extensive observation notes (log is >11,200 objects, now, I discovered that I really didn't care about my previous observations. I only wanted to know if I'd seen it before and whether it was interesting enough to revisit.
So now, instead of extensive notes, I simply put a check mark by the object, with an asterisk if it's interesting enough to revisit.
And that doesn't mean it has to be bright. The four very small faint galaxies in Burbidge's Chain are interesting even if I can see no detail in any of them and one isn't visible at all except on nights of excellent transparency and darkness. And some brighter objects (e.g. elliptical galaxies) may be uninteresting to view at any magnification.
So my highly subjective checkmark and asterisk is really all I need to know.
You aren't at that point, yet, so recording the notes is still important.
You can keep your notes in a program like SkyTools3 and simply avoid having to transfer any data.
I attach my observation log sheet that prompts me to look for details that, in my tiredness, I might otherwise ignore or not write down.Attached Files<li class="attachment">

Beginners Forum / Re: Sun Filter
« on: February 08, 2018, 07:30:56 PM »
Great, I also had the feeling that since so many of us here selected Baader for the solar filter, this stuff cannot be so bad after all

Apologies, if this question perhaps deserves a different forum topic - but how a good 4" refractor equipped with a Baader solar filter compares against those dedicated entry level solar scopes?

I am not talking about the Lunt solar beasts but rather the smaller Coronado PST ones. Can you achieve similar magnitude of detail or experience with a good refractor equipped with solar filter, or do those dedicated solar scopes have something that makes them unique, special?

What's the comparison between silicone adhesion and perforated center bolt attachment? Advantages/disadvantages?
http://www.rfroyce.c...l/mount CFB.htm

Beginners Forum / Re: Cheap Companion
« on: February 03, 2018, 06:50:12 AM »
There are a lot of decent small scopes out there now, Of the ones I can suggest because I have personally used them are.
4.5" Orion Starblast, a cheap totally portable dob with good optics, at $199.00 new
Orion also makes a perfect scope for you. the 90mm Mak on a Dob Mini-Mount StarMax 90 same price,
Go Scope a table top Refractor $129.00
They have the StarBlast 6" intelescope with computer, but it isn't ultra portable, but a lot easier than what you have and computerized.
Celestron has the NexStar 5" or 6". I wasn't impressed with the little 4" Nexstar, I had problems and the jump in quality between the 4" and 5" is
like going from a toy to a mini Observatory.
The Short Tube 80 is sweet but you need a Tripod and it isn't very good for High powers due to the Chromatic Aberration.
If you want to spend the money there are beautiful ED and APO refractors of 80mm or so that perform BIGGER than they are!
just depends how much you want to spend, if you want a motor or Computer, or exactly HOW portable you want.
My ETX 90 Astro I bought new when the ETX first came out has been a great scope and I get Surface features, Polar cap detail on Mars during
favorable oppositions, Saturn and Jupiter produce mind boggling detail with it! It has surprised MANY people with it's optical quality!
It is mostly for Lunar/Planetary/ Double Stars, but it is a scope that I will NEVER SELL.

Beginners Forum / Re: Determining limiting visual magnitude.
« on: February 02, 2018, 08:38:12 PM »
I suspect those of us with meters are more cognizant of the varying sky than those relying on NELM estimates or who don't have a method for evaluating. That is why we point out that a single set of readings only gives the user an idea and it takes more to know the range and potential of a site, orkeep track of what the sky is doing. Often the meter is used to confirm the sky is getting darker or brighter, it is quick and objective.

But when the readings are bright, I don't go after the lowest surface brightness stuff unless it will be my last opportunity for quite some time. It is usuallya waste of time and there are other targets. (It islike not spending a lot of time trying to split very close doubles in poor seeing. I might test the skies on an object to evaluate conditions, but I am not going to ram my head into a wall repeatedly.) Afterall, thatwas a reason to get the meter...and there are times when the sky starts bright for a few hoursand then darkens. When the meter goes from 21.35 to 21.65 (or 21.5 to 21.85)it is time to pull out the target list for the really tough stuff.

Finally saw the comet Friday night. We had great skies in New England, low humidity and no clouds. Observed from an Orange zone before the moon rose. Fairly easy to find in the 10" dob. Fairly large and low surface brightness. Maybe a hint of green. Looked like M51like M101 with no internal features, just a blob. Was able to see it in 8x50 finder.

Good to know.  Thanks.

Reflectors Telescopes Forum / Re: Travelling with a 15" mirror
« on: February 02, 2018, 05:22:26 PM »


The mirror would be too large for American Airlines' carry on regulations but should be within British Airways' limits if the protective case is less than 18" wide. I don't see what's the issue of bringing a mirror onboard. Is glass an hazardous substance? If you tell security not to touch the surface when they inspect the mirror they won't.

They envision you converting your strehl ratio 0.96 15" mirror into a field expedient stilleto by shattering it intentionally in order to do bad guy stuff. Pretty much none of them could imagine any other use for a whopping big piece of glass. Your insistence on keeping it close to you like you worship it will bring deep concerns. Strangely, they don't mind a telephoto camera lens -- THAT seems "normal" enough. But that much glass to look at the moon or stars is just 'baffling' (some pun intended).
Hey guys
so unfortunately I'm emigrating due to work, and I don't have much choice in the matter. To be honest I was hoping for some constructive advice!
Oberon told you what to do near the very beginning.
Most case builders would make hard foam wedges for the mirror side so nothing touched the alum.

If it is a temperature thing, it should be taken into account when designing. A proper astro mount should be able to accommodate at least -20° to +40° (considered normal temperature on this planet) and work without problems within that range, otherwise the manufacture should clearly specify its range.

I would agree that they are the same design. I almost get the feel from the roughness of the tube that it might have been a prototype.


General Astronomy & Observing / Re: New star in 2022 ?
« on: January 31, 2018, 06:03:45 AM »
i think the main point with this system is that we don't have enough information to identify exactly what is going on, and we don't have a sophisticated enough model of stellar merging and mixing to predict what will happen even if we did know exactly what is going on.

or, as the authors phrase it: "there is no physical basis for the exponential formula used to describe the early period changes, nor any insight into what sets the timescale."

the primary evidence, the exponential decrease in period, seems highly suggestive, but without knowing the physical dimensions of the two stars or the dynamics of the triple system with the mass 0.11M C component, we can't say much about the merging process.

the mass ratio estimated in the research paper, 0.23, and the effective temperature of around 5800 K implies a solar mass system with a B component in the type M mass range. i calculate the orbital radius as about 0.012 AU, or something like 1.8 million kilometers. the mass assumptions they make imply that the primary may be a type K star: this is not a potential merger of titans.

as the authors concede, "contact binaries exhibit timing variations for a variety of reasons, not all understood." they inquire into the possibility that the period of this binary is increasing simply because they are in perihelion with a third component, in the usual "hard binaries harden" scenario of dynamic change in a three body system. then they fit their exponential period decrease to the observed fate of V1309 Sco, without knowing, for example, if it was also a triple system. in other words, they have a comparison system, but no proof that the comparison is valid.

my sense is that this is one of those astronomical objects that now has justification to be observed more closely, even though we are unsure exactly what is going on. at best, it may give useful data about solar or low mass stellar mergers. at worst, it will provide a false positive useful to identify true merger pairs more reliably. either way, conjecture about what happens next is premature.

If you look up TPI Spreader on the internet you'll find that there's an aftermarket spreader and battery holder that will help stabilize the tripod.

Mounts Questions & Expirience / Re: Advanced-VX vs HEQ5 Pro
« on: January 30, 2018, 01:06:37 AM »

Re EQMOD: This, once upon a time, was a great advantage of HEQ5. Today, it's antiquated--use a planetarium program and SGP and never look back. I'd say the advantage is with the AVX.
EQMOD, a planetary program and SGP are all required. It is not antiquated
Serious, respectful question. What does EQMOD do that other third party software operating through ASCOM can't?
Dude we had this exact discussion before, why are you still doing this

EQMOD=Handcontroller/Driver for ascom

Synta mounts CANNOT connect to PC without it! It is not about being better, it is mandatory.

And for the OP I would say HEQ5 is a better design, this doesn't mean you can't get a bad sample though. But if you get a good one it is better than the AVX.

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