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Messages - Lcs King

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1
Instead of disassembling the EP why not engrave on a filter (clear or light color) and screw on to the bottom of the EP?

2
I had always been under the impression that the extra resolving power of increased aperture only manifests once you start increasing magnification, but the other night I was comparing the 3rd quarter moon in my 8" SCT with my 12" dob, and even at the same magnification, the 12" dob was showing enormous amounts of detail and texture that was just invisible in the 8" (despite better optics in the 8"). In neither case was I pushing magnification to either scope's limits. Seeing was good, but not great.

Is that normal or were my eyes just playing tricks on me?

3
ATM, Optics and DIY Forum / Re: The new Edmund?
« on: February 09, 2018, 03:55:26 AM »
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They didn't mention the detailed specs and quality control of their doublets. I am afraid that these are not comparable to those sold by Edmund. Many optical elements sold on Edmund are research-level, i.e. precise enough for serious scientific applications. While most telescopes are usually commercial grade, massively produced, slightly lower quality, much cheaper but still working well. This is not a fair comparison.

I don't know how can they make doublets that cheap. but... anyway, $200 is not a huge loss. you will always end up with a working telescope.

What a lot of folks don't know is that refractor objectives (and telescope mirrors) are all machine ground and polished now days. Even Roland Christen uses a machine to grind and polish his objectives. He does hand figure at the end. But achieving a 1/4 wave or better optic doesn't require hand figuring any more. Just a very expensive machine.

4
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.

5
Beginners Forum / Re: Total newbie here. What's next for me?
« on: February 04, 2018, 10:42:07 AM »
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You already have 4 of my favorite accessories-

Dew shield
Red flashlight,
A good book with some star maps (Nightwatch)
Vibration suppression pads

So thumbs up there!

A 1.25" 99% reflectivity dielectric diagonal will make sure all of the light from the scope reaches your eye (well, 99% of it anyway).  And they often have better build quality compared to the stock 1.25" diagonal. Astronomics, Orion, William Optics all offer upgraded diagonals.

If you observe alone you can skip it, but if you observe with family and friends and want to point things out to them, a green laser pointer can be great. Just be sure to buy one from a legit astro vender (like Orion or Howie Glatter) as the Amazon / ebay ones... well, you never know what kind of quality you are going to get.

Some 10x50 binoculars can make a fine companion to a telescope. I was just comparing the views of the Pleiades in my 6" SCT and 10x50s.

Eyepieces would be next... you can spend half a lifetime finding the perfect set for you.

Your scope looks to be fairly portable so cruise around and see if you can find a good dark sky site near you.

Enjoy the new scope. Have you tried the heavy hitters like Saturn, Jupiter, the moon, the Orion Nebula, and the Double Cluster in Perseus? Those might be big and bright enough to get your daughter back at the eyepiece. I have a nine year old son and am about to unleash my scopes on him.

I have a Celestron Cometron 7x50 on the way

I have tried the Moon, Jupiter, Mars and Venus. I have only seen Saturn once, I had I wake up at 3:30am to see it

6
Reflectors Telescopes Forum / Re: DobStand?
« on: February 03, 2018, 10:20:37 AM »
I guess I could use that first one for a stool ...

Mike

7
Quote
A lot of light scatter with dielectrics, get an enhanced aluminum one or a Baader prism.

Unlike a lot of observers, I've actually tested this.
There is more variation from sample to sample of the same diagonal than there is among all the different types in terms of light scatter and superior image quality.
I've seen lots of on-axis scatter in almost every type of <$300 diagonal there is, and I've seen virtually none in just about every type as well.
What I attribute that to is:
--the optical quality of the surface. If the quality of primary mirrors makes a difference, why wouldn't it on diagonal mirrors and prisms? When I worked at Scope City, I had a chance to use 20 different star diagonals on an Astrophysics refractor to compare the quality of the image. They varied in optical quality all over the place, and one was so good it literally yielded better star images than all the others. That could have been cooling of the mirror, or simply a flatter surface, or superior housing, collimation, or better suppression of light, or better-applied coatings. Whatever the cause, it was the best of all, and it had a dielectric coating. I think it just had a superior mirror. Second place was an older aluminized and overcoated mirror diagonal. I kept both.
--the cleanliness of the optical surfaces. I always wonder how recently the people who complain about light scatter have cleaned their optical surfaces.
I strongly suspect that many if not most star diagonals NEVER get cleaned. I see a lot of absolutely filthy ones in the field.

So to generalize that dielectric coatings cause a lot of light scatter leads to inaccurate conclusions. Some may, some won't.  Ditto with standard aluminum coatings.
And prisms aren't panaceas, either. They will vary. One of the best prisms I used was a cheap $49 multi-coated 90° prism in a plastic housing. I felt bad, because that prism justified a high-end housing. Another sample of the same kind was really poor. It's quite possible they were sub-contracted to different firms.

And therein lies a truth to it--there will be a lot of variation in quality from sample to sample in inexpensive star diagonals--more than you are likely to encounter on the level of TeleVue, Astrophysics, Vernonscope, Takahashi, Zeiss, and the like. A really good rule is that if you think there is something wrong with the star diagonal you have, try another one. You just might be quite pleasantly surprised.

8
Beginners Forum / Re: Orion XX12i Assembled! Whoo Hoo!
« on: February 02, 2018, 11:10:21 PM »
Been practicing taking apart the "yet to be named new telescope" and we will likely have first light this Saturday night at a dear friend's house...they have two young children who are very interested in stargazing. Can't think of a more appropriate way to do first light than to engage their children in a wonderous activity!
'

9
Quote
I'm thinking about doing the same thing with some Norway Spruces in southern Ohio.

In this area, Norway Spruces are pretty slow growing. Takes years to get any decent height to block anything.

10
Beginners Forum / Re: Getting the Most out of a Small Fast Refractor
« on: January 31, 2018, 12:22:33 PM »
I attended a observation night of a local astronomy club. About 30 people and about 20 telescopes ranging from 60 mm refractors to 12" Dobs. I got to look through a variety of scopes. I have to say that a small, short, 60 mm refractor provided a great view of the moon and was able to show Saturn, but not in as much detail as the larger scopes. I was impressed.

Still considering my next step but based on some of the reports here I might keep an 80 to 100 mm refractor on the candidate list along with 6-8" reflectors. Don't know what my next step will be. Might be 15X70 binoculars as those are not too expensive, can be hand held for short periods and can go on a light tripod.

Hope more people will report on their use of their small refractors. This is great for newbies like me.

11
I bought my Leica Zoom used several years ago. There is no dust in mine.

Mike

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Beginners Forum / Re: Good refractor on budget for planetary observing
« on: January 31, 2018, 10:40:21 AM »
I also have one of the Celestron C80ED (as in the ad above) and if you can find a used one in great condition they are a great 80mm for a very reasonable price.

13
Mounts Questions & Expirience / Re: iEQ30 Pro vs Sirius
« on: January 31, 2018, 10:03:03 AM »
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World moving on or staying has nothing to with it. You need a piece of software so that the computer can communicate with the mount. CDC can't do this on its own, neither SGP.
This is my last post in this thread.

I don't understand that last sentence. If you want to use any hardware on a computer system you need a driver. ASCOM drivers are the standard drivers used in astronomy for 3rd party programs to communicate with hardware. Most every program, most all hardware.

iOptron mounts are a menu option in SGP. No other software needed, except, as explained above, the standard ASCOM driver.

EQMOD uses a driver, just a non-standard one. I hardly think that's an advantage.

Feel free to have the last word, I'm done here.

14
Eyepieces Questions & Recommendations / Re: Is this filter the DGM NPB?
« on: January 31, 2018, 07:08:19 AM »
I just ordered a NPB from Dan, very fast service. To the OP, buy a new one then you know what you have, IMO.

15
Beginners Forum / Re: Newb with newb kids but they like the stars
« on: January 31, 2018, 06:36:16 AM »
The ETX 70 from Goodwill would be a fun scope to take on trips. Note there is no tripod in that offer so you would need a table or stool to sit it on.  And you can't be sure the computer system works when buying used.

Was it the price or the potential computerization that drew you to the ETX 70?

I have the ETX 80.

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