Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - Ryan Hernandez

Pages: 1 [2] 3 4 ... 9
16
Reflectors Telescopes Forum / Re: Compass on dob?
« on: January 29, 2018, 09:31:23 PM »
Quote
There must be a way to solve Pierre's problem.

Any reason why alt-az is the preferred coordinate?

The subject of adding some kind of coordinate location system to a ball scope has been discussed a few times in this forum and others over the years. It's the last "weakness" of this design that needs to be overcomed when compared to equatorial or dobsonian mountings. Over the last quarter century I've pretty much solved most of the remaining problems that afflicted ball scopes: I invented a drive platform which is much better than Poncet type platforms; I showed that by pre-loading larger scopes with multiple eyepiece turrets, the balance issue could be much more easily managed and even entirely eliminated; I tested the use of true hemispheres (rather than 2/3 hemispheres) which are much easier to find already made, to facilitate fabrication; etc.

But, remains the coordinate location problem.

People have tried using the equivalent of computer mouses to translate the rotational movement to a linear coordinate. Unfortunately the fact that the hemisphere turns around the optical axis makes this solution unworkable. In the '90's, Belgian ATM Alphonse Pouplier showed how he controlled an Astroscan to track satellites. However the scope had to be entirely computer controlled and the eyepiece could end up in an inconvenient position. But, the moment you touched the scope to bring the eyepiece to a more confortable observing position, you would loose tracking or coordinates.

That is why I was (still am) hoping that a digital compass could work. I know half a degree is not as accurate as the minute of angle systems currently in use but, that is all I need to get the object within a one degree TFOV eyepiece like the 20mm ES100 I have permanently mounted on my 20 inch.

Sometimes I feel like I'm facing a challenge like the one in the 18th century where the Government of England offered a prize to whoever would find a way to transport accurate time on vessels so they could accurately determine their longitude (the Longitude Prize). It took over 60 years for this challenge to be solved by clockmaker John Harrison. It's interesting to read that the objective here was also to determine longitudinal accuracy to within half a degree.

While watching "Tartuffe" last night (a play by Molière with too many words and not enough action), my mind ended up wandering as to how this "last frontier" could be overcome if I couldn't get the digital compass to work.

I'm not sure what the solution to getting a pointer attached to the ball scope to point a fixed grid is but I have a few ideas that need exploring. I will start a new thread specifically to find a solution to this problem. I will not offer a 20,000 pound prize but... you will receive my eternal gratitude if you figure this out before I do  .

17
Mounts Questions & Expirience / Re: ES G11 & PMC-8 plus TDM?
« on: January 26, 2018, 08:10:34 AM »
Never used an AP900 but a lot have. Just check Astrobin. I have no doubt it would perform as well. I refer to an AP900GTO. There was an older non GoTo AP900 which may have less precision.

18
Beginners Forum / Re: Some Really Basic Questions
« on: January 25, 2018, 10:52:02 PM »
I still use my old Skalnate Pleso Atlas of the Heavens. I have so many notations in it, I can't give it up.

19
Mounts Questions & Expirience / Re: ZEQ25 Polar aligment
« on: January 25, 2018, 07:27:48 PM »
Quote
Cosmos and all,

Thank you for the good advice and thoughts. I appreciate them very much!

All the best,

Brian

Hi Brian, the cosmos, viking, apollo, etc. are forum titles. The name is just above each.

Your altitude knob should pretty well be the same all the time if you image from the same place. Even with me going to different places around here as long as I am level I might have to adjust it a quarter turn at most. Got a couple questions though. What is the composition of your driveway? If gravel are the tripod legs sinking? If so get something heavy to go under it to give a good solid foundation, then level the mount.
Unscrew the knobs that lock you to the N pin on the tripod most of the way so you have the mount head that will go back and forth on the tripod pretty easily, and try to get Polaris centered with that leaving leeway both directions, then tighten them after aligning. Make sure you tighten then knob on the bottom of the tripod really good to the mount itself, and tighten up the spreader really good too. Use the locking knobs to level the mount before you put the OTA on, and if you've tightened everything like it should be that level should not change at all. Do your alignment like it shows on the controller, making sure to put Polaris dead center on the inner circle, not the outer one.

20
Quote
Quote

Quote

Not sure why you would want to do this. It makes little sense to goto a target then not be able to track it.

If aALT-AZ can track without any physical alignment, why a Gem couldn't do it?
Different animals. The Alt/Az uses Stars (usually 2 or more) to get a model of the sky and tracks in both Alt/Az axis. A GEM relies on the user aligning to Polaris to align with the earths rotation as it tracks (one axis) to counter this.

Mike
But why a GEM could not use a few stars to get a model of the sky and tracks using its both axis?

Think about it... What is different between a Alt/Az and a GEM with declination set to 0 degree? Now, why the sky model could not take into account that the azimuth axis is tilted?

21
Mounts Questions & Expirience / Re: CGEM DX Optical Encoder-broken
« on: January 25, 2018, 03:48:13 PM »
Thanks for the reply ccard, That`s what i thought too, so on the 25th i ordered the 4ET 256 098 s d d2 with the wire kit from us digital it came Friday. The wiring was tricky from J 1 on the celestron board was placed wrong as to the 4ET J 1 was placed in the right place, celestron sure makes it hard to do this, as i am an tech i manged to figure it out as not to blow the encoder so i followed the leads on the celestron chip and code on the wires to find how it should be installed opposite that of the celestron chip. Well it worked Pleased to say the right 4ET encoder chip will work for celestron mounts. That said the reason these encoders blow a lot in celestron mounts is mainly do to unbalanced mount/the disc spinning over the encoder in all to much vibration, and the encoder lets go on 1 or more of it`s legs and that`s lights out. In ten years i have had 4 encoders go on me, in spite all my efforts to keep those factors to a minimum. I am sick of dishing out $270 CAD. to get a motor to Canada. So i went this route and it works, also you stated the shaft is 2.3 mm and the 098 is 2.5mm and the 2.3mm is no longer available, WHY IS THIS? i think some of us know why! I used lock tight and very carefully gaped and centered the disc, i have the Cgem DX and the GT Adv Cg5 goto and it happens to both of them, always the encoder, i have 3 motors where the encoder went bad and now i can fix them all at a fraction of the price. I think celestron is way over rated, over priced junk toy encoders, where as the 4ET encoder is coated in a clear epoxy or something like that, this add more strength to the chip, i suspect they will last longer, only time will tell, and oh yeh i will never buy there product again, I`m going to sell off my mounts and go EQ8

22
61 miles or 1 hour and ten minutes to a wonderful gray, bordering on black.  42 miles to a decent blue zone site or a 45 minute drive.  Yes, the extra 20 to 30 minute drive is worth it.Then there is 3 to 4 hours to some of the darkest sites in the lower 48 on Federal land.  I get to these in the summer once or twice.  Notch Peak one of the darkest sites in Utah is 3.5 hours away. I try to go there at least twice a year in the fall and early spring/late winter. I'll offer a XT10 if anyone is out here in SLC for a weekend and want to observe.  You can ask Chris from NC or FirstSight on the quality  of the observing sites. Just a friendly offer (of course I'll bring the XT10 with my 14 inch  to the observing location). Yes, I observe year round and am equipped for low temps and if your dressed, I have an outdoor heater I can setup to keep you warm, or at least thawed if your here in the winter.

23
General Astronomy & Observing / Re: Dark sites near Las Vegas
« on: January 25, 2018, 02:04:20 PM »
Quote
Due north about 200 miles is Ely, Nevada. Ely was my home town. I had Mag 6.5 skies out my back door. Ely is 6,400 feet above sea level. I enjoyed my 4 inch, F10 Dynascope more in Ely than I did years later with telescopes later 20, 18, 13.5, and 8 inches due to its dark skies. That taught me something very important--dark skies may be the most important factor in observational astronomy, not size of the objective. The problem with viewing in the Las Vegas area is how far you need to travel to shrink the light dome. Tonopah is also a good option. There are a lot of people who view from Tonopah due to its dark skies, and excellent atmospherics.

I went to a Star Party outside of Tonopah (Central Nevada Star Party) about ten years ago and as you report, the skies were wonderful there. I'd also imagine that the skies at Cedar Breaks National Monument at 10,000ft would be exceptional too but snow could inhibit using that area in the winter months.

24
ATM, Optics and DIY Forum / Re: pitch help
« on: January 25, 2018, 01:12:36 PM »
Quote
Greetings everyone!
I have a couple question regarding polishing pitch:
1) Is it true that Cycad just shut their doors and won't produce anymore?
2) What would you suggest to substitute Cycad medium pitch? Mainly used on IR crystals as Ge, Si, ZnSe, CaF2 etc for both spherical and flat optics in a 68 - 73 F room
3)Are there any other pitch manufacturers besides Cycad and Gugolz?

I know that CN is astronomical forum but I find this community really experienced and looking forward to your advises.
Thanks!

Since Ed mentions AccuLap you might want to have a look at their descriptions online, note that they will manufacture it to spec (in largish qtys) and since it's engineered they can make it do what you want...

It's here: http://www.suttonsci...m/products.html

25
The issue here is that Windows 10 does not have a simple way of connecting to an Ad Hoc network. Folks have been requesting that Microsoft add support back in. Microsoft is taking the stance that Ad Hoc networks expose the user to significant security vulnerabilities. There does appear to be a method for getting around this by using netsh from a command prompt.

26
Correct. Major time-suck.

27
Quote
I am really, really close to purchasing my main, at-home telescope (Zhumell Z8 Deluxe). However, apart from my Tasco 10x25 binoculars, I would still like an inexpensive, but fairly decent grab-and-go refractor for quick glimpses or hitting the road. Can any of you recommend for or against these three models, or suggest anotherone in the same price range--less than $100--that I might consider?

Meade Instruments 209003 Infinity 70 AZ Refractor:
http://telescopes.bu...telescope-blue/

Orion 10034 GoScope II 70mm Refractor Travel Telescope (and Moon Kit):
http://www.telescope...34/p/103017.uts

Celestron 21035 70mm Travel Scope :
http://www.amazon.co...,p_36:5000-9500

http://www.celestron...table-telescope

I appreciate your insights!


(http://www.bhphotovi..._refractor.html)

The Meade Instruments 209003 Infinity 70 AZ Refractor purchased through B&H meets the price point and has features suitable for an astronomical telescope, i.e., slow motion altitude mount, f10 OTA to minimize achromatic coloration on bright targets, 90 degree diagonal, 2X Barlow, red dot finder and two modified Kellner eyepieces of 26mm and 9mm focal length which when used with the Barlow would offer magnifications of 28X, 56X, 78X and possibly 156X.

For $80.00, what's not to like?

(Corrected typos)

28
Eyepieces Questions & Recommendations / Re: APM 10 MM Ultra Flat
« on: January 23, 2018, 08:43:12 AM »
Hi Cliff... I'm wondering what scope, or binoculars you were using the 18mms with?
In my f/5.5 (120mm APMs) I find the UFs to be absolutely perfect to the edge. No color issues and tiny stellar points REMAIN tiny stellar points until they just disappear fro the field.
Were you using a shorter (or longer) focal ratio instrument?

Mike

29
Beginners Forum / Re: Eyepiece question for a beginner
« on: January 23, 2018, 07:24:25 AM »
Quote
I just order my first telescope (Meade LX200 10”). Should I start with the 1.25 or 2 inch eyepiece sets. Is there a particular brand that is preferred for eyepieces?

A 10" SCT is a nice way to start, congrats!

Generally speaking, you only need 2" eyepieces if you enjoy wide angle, low power observing. Also nice for BIG objects like the Pleiades or Andromeda, and for seeing gems like the Orion Nebula or the Double Cluster floating there in space with some sky around them.

Personally I love cruising around the crowded areas of the Milky Way at low power. So many stars.

If that type of observing appeals to you, sure, grab a 2" 99% reflectivity dielectric diagonal, and go with an eyepiece like the 40mm William Optics SWAN, 35mm Tele Vue Panoptic, or 32mm Orion Q70. Explore Scientific also puts out plenty of nice eyepieces. Lots of options, mainly coming down to price and Field Of View (wider field = more $$$). Though at f/10, your scope should be easier on eyepieces compared to a dob at f/4.

30
Beginners Forum / Re: Wow! Andromeda for the first time
« on: January 23, 2018, 05:36:03 AM »
One of my most memorable observations of M31 was from Cherry Springs State Park in 2005 through a homemade 18.5" (yes, 18.5") Dob equipped with a binoviewer capable of low-power views. It was unlike any view of the galaxy that I'd ever seen.

Dave Mitsky

Pages: 1 [2] 3 4 ... 9