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Luna-tic

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Posts posted by Luna-tic


  1. On ‎30‎/‎01‎/‎2019 at 07:26, ejp1684 said:

    I've been using a Leisure battery 20ah for a couple of years now with no issues. Cost £35. After 6 hours observing, including a small heater for the guide scope, it rarely goes below 50% charge when it's still pushing out 12.4v. Built a box for it and secure connections. Key to using it effectively is the electronic charger.

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    Very nicely done power supply, looks great and nicely laid out.. I just finished mine, will deliver 12VDC or 115VAC with included inverter. I'm using a 96 amp/hr deep cycle wet cell lead-acid battery.

    On ‎30‎/‎01‎/‎2019 at 08:49, Carbon Brush said:

    If you choose to carry a big heavy lead acid battery (the cheapest solution) then the type is relatively unimportant.

    In an evening of running a mount you are not going to eat into much of the capacity. So if you have a grotty old battery that won't start the car on a cold morning, or won't hold up the headlights beyond half an hour, it is probably good enough to run a mount. This statement assumes a battery with a general loss of performance through age and sulphate. If an individual cell has failed, that is a different story.

    If weight is of interest, or you are going to have to pay full price for a battery, then you are far better spending on something with a lithium battery.
    Excellent life expectancy. Superb cold performance. Inbuilt charge and discharge monitors prevent you from doing harm to the battery.

    If you want to run a mount, and lots of dew heaters, and a camera, and other things, then you ought to get the calculator out to ensure a small capacity lithium package is going to be good enough.

    Just my take on battery power - not necessarily everyone agrees!

    Hope this helps, David.

    Very true. Generally, the heavier and more basic a battery is, the less it costs per amp/hr. capacity. As you go up in capacity,  up in technology (AGM or Lithium)or down in weight, the prices climb correspondingly. Choose your priorities in weight, technology and capacity, then look at what's out there.

    On ‎02‎/‎02‎/‎2019 at 04:48, Aldebaran5 said:

    if you do the maths, you can work out what you require. A 10amp hour battery will run for 10 hours on one amp. If your unit has a drain of half an amp then it should last for 20 hours, so work out the equivilent usage of all your pieces to obtain the amperage in use. 16 amps will run approx. 3600 watts.

    Keith

    As a very broad rule of thumb, you can figure it that way, but you can only count on about 80% of the total capacity to be useful, and that depends on several conditions. A 12 volt battery delivering 16 amps only gives you 192 watts, according to Ohm's Law, and that is at 0.75 ohms. You'd get 3600 total watts over 18.75 hours at that voltage and load.    Now, if you were at 220VAC and drawing 16 amps, you be using pretty close to 3600 watts.

    A telescope mount of moderate size will draw anywhere from 0.25 to 0.75 amps during tracking. At full speed slew that will increase to 3-6 amps. If that is all you have to power, you can run most of the night on a 20 amp-hr. battery doing observation. I can run a dew heater at full power, my mount, a laptop and two cameras at less than 7 amps total continuous draw. So, for 6 hours, I'd use about 42 amp/hrs. Realistically, it would be longer than that, because the 7 amps is maximum, (during slewing) and drops about 2.5 amps during tracking. Part of the draw is from the inefficiency  in converting 12VDC to 115VAC through an inverter, which part of my gear runs through.


  2. On ‎04‎/‎02‎/‎2019 at 14:12, Taz777 said:

    Does anyone know of any good astronomy clubs that are suitable for beginners located west of London?

     

    On ‎04‎/‎02‎/‎2019 at 15:42, Stu said:

    Not sure what your definition of West of London is …..

     

    On ‎04‎/‎02‎/‎2019 at 17:02, Taz777 said:

    Let’s say a 6 mile radius of Heathrow would be okay.

    Glad you narrowed it down a bit. I was going to say there are a boatload of them across the big pond, which is, as you asked, west of London. If ever in the States, PM me and I'll treat you to ours.

    • Haha 1

  3. 7 hours ago, djpaul said:

    Mmm might go for the 8ah. .

    That's 10 hours ?

    Generally, plan on about 80% usable capacity, max. Once you get to that point, the voltage starts dropping, and the mount will shut down from insufficient voltage. Also, with lithium batteries, the nominal voltage is less than a lead-acid battery, right at 12VDC, so any heavy draw will drop the voltage more quickly to an unsuitable level. If your mount draws 0.75 amps@12VDC, count on about 1.5 amps to account for slewing, temperature, reserve, etc., and select your battery capacity accordingly. Celestron's Power Tank Lithium is 17 amp-hours and will run my AVX about 4-1/2 - 5 hours on an observational night of moderate temps (battery capacity drops in cold weather).

    1 hour ago, noah4x4 said:

    That leads me to an important consideration. The amp-hours rating of batteries can be misleading. Even with a quality brand like Tracer what matters most is its watt hours capacity and hence the watts consumed per hour (watt hours) by the device. Many battery manufacturers don't state their watt hours. But the power demands of a telescope depend on what it is doing. Think of it just like a car using more fuel when accelerating uphill. Heavy repeated slewing will deplete a battery faster than tracking.

    Most large batteries are rated by amp-hour capacity. It's all just a matter of math, volts X amps = watts; not hard to convert watt/hr to amp/hr and back, but if you assume 12VDC, as all our battery powered gear uses 12VDC, amp/hr is easier to figure duration by. The higher the amp/hr capacity, the higher the current drain necessary to drop the voltage under load, and the reverse is also true. A marginal capacity (for the need) battery will drop its voltage faster under a heavy load relative to the overall capacity of the battery. The current-draw rating of the mount spoken of by the OP is probably what it uses during tracking, and you can count on that tripling or more under high speed slewing. I just tested my EQ6R-Pro last night, as I have just built a field power system and was seeing what it was capable of. I have a battery minder that reads out volts, current and watts.  My Skywatcher (with an Edge HD 8 mounted) tracks at 0.5-0.6 amps; under a go-to slew at max speed, it draws 3.5-3.7 amps, and curiously enough, as it slows to its "centering speed", it draws 4.1-4.2 amps momentarily before dropping back to 0.6 amps tracking. A night of observing will take more power than a night of imaging just to run the mount, and current use is cumulative.

    I had enough equipment connected to the system to draw around 10 amps; the voltage only dropped by 0.13 under the test load, from its nominal no-load of 12.9 VDC. That is with a 96 amp-hour deep cycle battery


  4. 23 hours ago, RayD said:

    Ah yes.  They do DC ones too here.

    That one looks identical to mine, but mine  goes by another brand name. I imagine they all come from the same factory in China.

    I did an all-up test on my system last evening. I hooked up my EQ6R-Pro mount, the dew heater strip (turned up full) for my C8 corrector, (both of those to DC connections), my DSLR with its AC adapter, and my laptop to AC power. The battery was at 12.9 volts no load when I started, slightly less than its 13V full charge. With all the above named gear running, voltage stayed at 12.32-12.45V, current load varied between 4-6.5 amps (current drain would go up about 2.75 amps when the mount was slewed), and was using a total of 54-56 watts, 10 of those coming through the inverter (it has its own watt/volt display). Total energy drain over the 15 minute test was 1.35 amp-hours.

    This bodes well for a long session, The only other items I might connect would be an EP dew heater, which would draw less than the larger corrector strip, and my guide camera. I could even run a second mount without undue load.

     

    Edit: It's interesting to note the amps drawn from the mount alone. While tracking, as one might expect, it's drawing 0.5amp or less. When it goes into a high-speed slew, as when you select a target and go-to it, current increases to about 2.75 amps, also as expected, but when the slew drops to its "creep mode" as it centers on the target, current increases to almost 4 amps before dropping back to the 0.5 amp tracking level.

    • Like 2

  5. 4 minutes ago, Davey-T said:

    Looks pretty comprehensive, the only thing missing is a solar panel connection which may be needed come the apocalypse :grin:

    Dave

    Easy enough to add, and in the plans. Hopefully, any apocalypse will wink out civilization so nobody has to suffer long. I'd much prefer a simple disaster like a blizzard or wind storm.?

    • Like 1

  6. I just finished a field power system that will proved me both AC or DC power. The heart of the system is a 96 amp/hour wet cell deep cycle battery, so light weight wasn't on the priority list of features. It sits on a small dolly, so it can be moved relatively easily, but I wouldn't want to haul it across a field. I can usually take my cargo trailer within a few yards of my viewing spot, so it isn't a big deal. It will sit below the tripod, I can even strap the tripod to it to add stability.

    AC power is provided by a 1000 watt pure sine wave inverter, DC power is channeled through a RigRunner. There is a master power switch that shuts down everything and isolates the outputs for when I charge the battery. The system has a main fuse, and the inverter and each DC connection are individually fused. It has a battery monitor that shows volts, amps, watts and energy, and the inverter has its own monitoring panel and has a 5V USB port. The system has a secondary use as a backup power for loss of power scenarios in the home, to augment a small generator. The battery is contained in a box made of 1/2" plywood with a 3/4" pressure treated base, and is finished with a spar urethane, so it should "weather the weather" . Of course, rain would be out, but who sits in the rain with a telescope?

     

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    • Like 3

  7. On ‎06‎/‎02‎/‎2019 at 06:09, Jonathan B said:

    Poor initial Go-To. Polaris alignment- I can rotate RA axis and it stays on the engraved circle, which is itself aligned.

    Do  I have to rotate the RA so that Polaris is at the correct hour position at the start of each session, which then will not be the "home" position previously set?

    1-Level the tripod, then attach the mount, balance scope and attachments, input necessary time and location data, as for any session. Place telescope in Home position. 

    2-The HC will tell you the clock designation for Polaris. Don't worry if the time marks on the ring are upside down or at some angle; adjust the altitude and azimuth screws to place Polaris in the clock position indicated, assuming the top of the polar scope view is 12 o'clock. This will adjust the axes to the proper angle. The HC will also tell you your Alt-Az error once the polar alignment is done, so you can improve it if you want. I leave mine as -is, generally and am usually within 4-5 minutes of arc accuracy. Then I do a 3 star alignment. My go-to's usually have a star within the FOV of a 20mm EP.

    I assume the NEQ6R is same/similar to the EQ6R-Pro that I have. It sounds like the PS reticle is the same


  8. I found that the DSLR's screen is just too small for me to see well, even with a Bahtinov mask, I can't see the diffraction lines well enough to determine a good focus. (I'm also getting older) I bought an accessory  7" screen that plugs in the HDMI port on my DSLR. It has a hot shoe mount that allows attachment to the camera, although that doesn't work well for telescope balance, and also comes with a gizmo that allows strapping the screen to a light bar (made for professional photographers). It works well clamped to a tripod leg. The screen has quite a few functions that work well for AP. The one I like is a focus function, it puts a fine red line around the screen subject when it is in focus. The screen will show anything bright enough to be seen in the camera's screen, it is a 1920x1200 pixel resolution. The screen is battery operated, has its own battery on back that removes for recharging, and it will last long enough for a good imaging or viewing session at night. I sometimes use it at outreach sessions by installing the camera on an EP (or use it prime focus) and viewers can see the image on the screen rather than having to squint into the EP. Works great for young kids who want to grab the scope. The screen backlight can be changed to several colors, including a red screen, and has a light shield that helps block any glare for other observers. The screen is fairly bright, so I usually hang a small dishrag over the screen shield so it doesn't ruin my or others' night vision.

     

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    • Like 4

  9. On ‎19‎/‎09‎/‎2018 at 14:49, Lead_weight said:

     I've taken particular care to stick under the rated weight limit, and a focal length of no more than about 900mm. For visual you can go above that, but for imaging, you'll find it's not precise enough (even with guiding) go do longer focal lengths or heaver imaging setups (above 20lbs).

    You can get by with the AVX using a longer focal length, but you'll need good guiding to get decent results and will work harder to get them. I like my AVX a lot, and started out using an Edge HD 8 (2000mm F/L) with it. I've since bought a heavier mount to use for AP, and the AVX is primarily my visual mount now, although if I have the Edge set up on my EQ6R Pro and want to get a widefield shot without changing things around, I'll put my shorty refractor (478mm F/L) on the AVX and get great results.

    The stiffness in the RA lies at least partly with the grease used. I disassembled my RA and Dec, cleaned all the grease out, and re-greased it with Lubriplate 130-A, and while it still doesn't spin like a ball bearing does, it is much 'looser' than before. The mount doesn't come with a polar alignment scope, and rather than get one later, I'd recommend saving for a Polemaster;  you'll get an easier and more accurate PA. The ASPA or 3-star/calibration star alignments do very well, or you can opt for Starsense.

    • Like 2

  10. Referring to the picture of the worker out on the dish; you can see the dish is made up of many individual panels. There are, in fact,  2004 of them. The dish is an "active" surface, meaning it can change its shape to compensate for expansion, contraction, and sagging in order to maintain its highly tuned parabolic shape. There are 2209 actuators under the panels that move the panels to keep them aligned. The panels have a surface accuracy of 50 micrometres; the scope can operate at frequencies between 290 MHz and 100 GHz.


  11. As promised, a few pictures while on the telescope during the tour. 1st picture is a worker out on the dish, you can see how large it is. 2nd picture is at the dish level, looking up at the underside of the array platform, which is 325 feet up. 3rd and 4th pictures are from the array platform. It's still another 45 feet to the secondary reflector, but it can only be accessed by climbing the structure.  The telescope in the distance is the 140 foot telescope. Last picture is the base of the telescope, not the size of the trucks below it.

    A couple of interesting notes about the 140 foot radio telescope. It is on an equatorial mount, one of the largest ever built. The RA bearing is the largest ball bearing ever manufactured.

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    • Like 2

  12. 3 hours ago, Marc2B said:

    BTW, English isn't my native language, I hope you'll forgive my mistakes ;)

    English is my native language, and you're doing a better job than I do most times.?

    Of course, I live in the US South, so our English can be a little.....different.


  13. On ‎21‎/‎07‎/‎2018 at 04:08, newbie alert said:

    I wouldn't know as yet as I'm about to start going down this route...but aligning the mount on 3 stars don't take long..

    I wasted 3 weeks off my life trying to use starsense..best thing I did was getting rid if it..

    I'm beginning to think the same thing. It works well when it works, but I've found it to be occasionally inconsistent. Some nights I get perfect star alignment, some nights I think it's on a different planet than I am. Most times are okay. I had purchased the Celestron Starsense before getting an EQ6R, and had wondered about inter-compatibility between the brands. It was quickly apparent that the connector for the hand controls was not compatible between brands, and I was somewhat disappointed I couldn't use the Celestron Starsense on the Skywatcher mount. However, when I saw how accurate the go-to was on a 3 star alignment with the EQ6R, I quit thinking about it. As for the AVX mount,  doing a 3-star alignment and a couple of calibration stars doesn't take that much longer than using Starsense, and I get as good accuracy, so I've sort of parked the Starsense in its box for now. I'll keep it for a while, but may sell it at some point. 


  14. 2 hours ago, LukeSkywatcher said:

    I bought the 17Ah a few months ago. Its pretty heavy.

    The trade-off is price vs. weight when buying suitable battery packs. OP could go with the Powertank Pro Lithium, its a 158wh (translates to 13.16 Ah at 12VDC) Lithium Iron Phosphate (LiFePO) which weighs 4.5 lbs., but costs over twice what the standard power tank costs. I would have suggested the Powertank Lithium as a great match for his mount. It's smaller than the Pro, has 86.4wh (7.2Ah) and only weighs 2.25 lbs. I use one with my AVX and it will power it for a long night or two short ones. It's smaller than  Foster's Lager oil can. I figured the OP was looking for something more economical.

    I use one of those car starter setups like cletrac shows to run my EQ6R, it'll power that mount for 12 hours with frequent slewing.


  15. On ‎29‎/‎07‎/‎2018 at 17:31, nelgin said:

    Hi all,

    Recently I've been toying with the idea of going with a 10" Schmidt-Cassegrain but research shows that can be difficult if viewing objects overhead but shouldn't be much of an issue if doing photography. Obviously the eyepeice for the Newtonian can end up in strange positions too.

    As far as photographing I want to capture it all, the Moon, planets, clusters, nebula, DSOs etc.

    The budget on the scope/tripod is about $2000-2500 though I don't have to spend of that, of course, especially if the best advice is just to stick with the 8" and get a new tripod.

    On the camera side, I've not really decided or even looked into that. I guess something digital that I can attach to the laptop and control from there as far as apature size and exposure duration etc...I don't really know.

    Right now, I'm open to suggestions and options. Specific recommendations are appreciated.


    Thanks,

    Nigel

     

    You would be hard pressed to find a 10" SCT and a mount suitable for astrophotography in the budget range you mention, unless you find a good deal in the used market.

    Difficulty with seeing directly overhead with a SCT isn't so much a consequence of the scope itself as it is the mount. A fork-type mount may be difficult to use overhead, especially if you're trying to take pictures, due to clearances between the bottom of the fork and the eyepiece or camera setup. An offset fork is better than a straight one, but an equatorial mount is much more suitable. Also, unless you have a fork mounted on an equatorial wedge, you will have issues with field rotation while doing photography.

    A decent DSLR will get you started in AP. You may capture some short exposure single images, or use short exposure subs and stack them with a computer program, but long exposure photography will require guiding, which means a second camera and small scope, attached to the larger one, and directed by a computer. 

    The better way to start out in AP is with a small refractor and a mount with good tracking ability and provisions for computer control. The "classic" AP scope would be a 3 to 4" aperture, focal length of 300 to 450mm, a focal ratio of f/5 to f/7. Ultimate would be an apochromat, next best an acromat or ED apo. You could find a nice apochromatic 80mm f/6 and a suitable mount within your budget. I have a William Optic GT81 (81mm apo, f/5.9) and a Skywatcher EQ6R-Pro equatorial mount, both would run at the upper limit of your stated budget, but would need little upgrade for quite a long while. Just add camera and a few accessories. If at some point you wanted to add a SCT, the EQ6R will easily handle an 9.25" SCT. I switch back and forth between my refractor and an 8" SCT, using a couple of mounts. The AVX is a decent starting mount for AP with a small scope, not so much with a bigger one, but will work visually.

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  16. 10 hours ago, New said:

     

    Hi everyone! I'm new in astronomy and I'm searching a website, which enables live viewing in space for free! 

    I don't mean to websites that show pictures of plants\stars!!

    I'm searching a website that enables to watch live in space, to make zoom and to see the gases of space in the screen ( like it's seen through a real telescope).

    Hoping to get some help  :)

    Thanks!! :))

    If you have a link to such a site, please post it.

    If you're looking for a way to see the sky in a real-time scenario, try downloading Stellarium. It's free, and is a virtual sky. You can zoom in and out, click on desired objects and get all the pertinent information about them, search for specific objects, there's even a configuration box where you can input your own telescope specs, and then view an object and see it like you would through your own telescope. Stellarium will also control your telescope with the proper connections.


  17. The difference really boils down to whether you like black or white better. Maybe it's more popular in the UK, I couldn't find one of the top 4 or 5 sellers in the US who show the HEQ5 in their ads. It's a very close rebrand of the Orion Sirius EQ-G (both are made by Synta). As an owner of an AVX mount as well as a Skywatcher mount (EQ6-R Pro), I'm beginning to like the Synscan better than Nexstar for navigating the menu. But between the AVX and HEQ5, even though they are rated the same capacity, I think the AVX is a slightly more robust mount.


  18. 40 minutes ago, Minhlead said:

    I personally wouldn't go with the 6" if I could afford the 8". That is to say If your use is strictly visual I doubt the 8" will make much of a different since 8" on planets is quite small it self. 

    The 8"  mirror is 35% larger than the 6" in area, and has significantly better views. All other things being equal (price, mainly), the only way I'd take a C6 over a C8 would be if transporting it was the prime consideration. The C8 is fairly lightweight, but quite a bit bulkier than the C6.

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    • Like 1

  19. This isn't so much to advertise an upcoming party as to share my experience at a recent one. If needed, mods please move to a more appropriate section.

    I realize much of the readership on SGL is European and UK, I thoroughly enjoy reading what like minds are doing across the big pond. I thought I'd share a bit about the star party I attended this past week on my side of the Atlantic.  Starquest XV is held yearly at the Green Bank Observatory in West Virginia, one of the most beautiful areas in the eastern US. GBO is a radio astronomy observatory, and is home to the largest steerable radio telescope in the world. At full tilt, it is over 135 meters tall, and the dish measures 100 meters across and encompasses 2.3 acres in area. It took ten years to build and weighs 17 million pounds. Located at the edge of a large national forest, it is also within the national Radio Quiet Zone, a square roughly 50 miles on a side, where radio emissions are highly regulated in order to minimize RFI at the observatory. There is no cell phone service within 20 miles of the telescope, and once on the observatory grounds, anything that emits energy is highly shielded or forbidden. You can't have a digital camera within a mile of the telescope, and the control room and the computer room in the visitor center are built within huge Faraday cages to trap the RFI. Microwave ovens are also caged in the cafeteria.

    I was amazed to learn that a cellphone, at a range of 5 kilometers, emits RFI in the 2.5 million Janksy range. The telescope routinely picks up cosmic energy in the 0.002 Jansky range, so it's easy to understand why RFI from local sources can impede reception of desired signals. As part of the star party, attendees can sign up for a tour of the telescope;  staff members take groups of four or five up on the telescope as far as the array platform, which is 100 meters up with the telescope in its "maintenance park" position. This position puts all the platforms and catwalks in a horizontal position, and the two elevators in vertical positions. The star party is held during a maintenance week, and there are numerous workers in climbing gear all over the scope, painting and repairing various parts on a specific schedule, in order to keep the telescope operating reliably.

    Riding up the first elevator takes you to the level of the altitude pivot (the scope uses an alt-az type mount). You walk along a catwalk to a second elevator which takes you up the reflector array arm as far as the array turntable and control room (unmanned during use). You get off and are standing on an open platform over 100 meters off the ground. All the platforms are open grating, so a glance down at your feet has you looking straight down at the ground and the structure between it and you. The only portion of the telescope above you at this level is the secondary reflector, another 15 meters up. Climbing gear is required to get there. The telescope uses an off-axis design, the secondary reflector and receiver array do not hang over the primary dish, which is a modified parabola.  Signals from space reflect from the primary up to the secondary, which reflects them down to the receiver array. This array is on a turntable about 3 meters in diameter, which can be rotated to place the desired receiver in the beam path.

    As we work our way back down the upper elevator, we stop at selected platforms to allow us to view different portions of the structure and mechanism. All the drive motors on the telescope are hydraulic, so they emit no RF while moving the telescope. We stopped at the altitude drive, where we saw the four motors (each about a meter in diameter) that tilt the dish. The staff member told us that the telescope was so finely balanced that a single person could move the dish if the motors were not engaged to the geared track. There is a massive counterweight built into the gear arch used to move the dish. Back on the ground, we saw the four sets of drive motors (four motors to each set, and twice the size of the altitude drive motors) that are used to point the telescope in azimuth. The telescope rides on a circular track and can rotate in azimuth thirty degrees per minute, and can pivot ten degrees per minute in altitude. There is also a central pivot point that shares the weight of the telescope with the azimuth track. Both of these are concrete structures that extend almost 20 meters into the ground to bedrock. The tour took about 1-1/2 hours, and much as I enjoyed it, I was happy to get back on solid ground. The scale of this machine is hard to describe, and everywhere you are on the structure is highly exposed. The view from the top is amazing. Since digital cameras are not allowed within almost a mile of the telescope, pictures can only be made with film cameras. I couldn't find a battery for my old Canon AE-1P, so I bought a cheap disposable 35mm camera to make pictures while on the telescope. I'll post some up when I get them developed. The pictures shown below were made just under a mile away, at our observing field, where I was camped for two nights.

    The star party itself is fantastic. The Observatory is a tourist destination and strongly promotes astronomy and astrophysical sciences. There are scheduled speakers on topics from observing Mars during the opposition, to techniques for deep space imaging and planetary imaging, to new discoveries and technologies in radio astronomy. Attendees can sign up to learn how to control and operate the 40-foot radio dish, and can get work time on the scope at night. Our observing field is about three acres with fantastic horizons, even though we're in the heart of the Appalachian Mountains. Thursday at dusk looked like a washout for observing, about 70% clouds at dusk around 8:30 pm, but by 10:30 the skies were almost totally clear and stayed clear until about 2:30 am. There is no sky glow except for one small area where a ski resort lies about 25 miles away. The sky would classify as a Bortle 2 or at worst a Bortle 3. The Milky Way is clearly visible in its full arc, and seeing was very good. I had two telescopes set up, a WO GT81 on an AVX mount to view wide field, and an Edge HD 8" on an EQ6-R Pro to get higher magnification views. The telescopes on the field were varied, the largest was a 24" Dobsonian, and there were several 10" and 11" SCT's and a few 5" refractors. One gentleman was imaging with an Edge 11 using Hyperstar. I saw a few of his early constructs, he was imaging the Lagoon and Trifid Nebulae, and they were awesome. I stayed two nights; Friday night was even better than Thursday, by 8:30 the skies were clear and remained so until around 4 am. I spent most of my time in Scorpio and Sagittarius, but wandered around the zenith quite a bit. The site is at 38*N, Vega is directly overhead around midnight.

    I had a wonderful time at this event, and will probably make it a yearly thing; it's a five hour drive for me, but the people, event and the dark skies are worth it. Now for a few pictures; first few are the telescope itself. Remember these are made almost a mile away. The first picture is in the "maintenance park" position, you can see the lower elevator track and the horizontal catwalk that goes toward the left. The small box at the intersection of the catwalk and elevator track is the elevator car, which is just slightly taller than a person, so you can get some idea of scale.  2nd picture is the dish at full tilt, facing toward me, and the third picture is the telescope  facing away. Fourth and fifth pictures are my camp spot and the gent with the Hyperstar/Edge 11. Last picture is the beautiful 24" f/5 Dob.

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    • Like 5

  20. I have an AVX and it's a good mount for the C8 (I have the Edge)  visually. May be borderline for a steady imaging platform for a long focal length but is great with shorter F/L's, I use a WO GT81 (F/5.9, 478mm F/L) on it, too. Go-To is accurate with the ASPA and 3-star alignment, even better with Starsense. I recently bought a Skywatcher EQ6-R Pro and it is awesome, but may be a bit over your budget if you're looking mainly at the AVX and EQ-5.

    • Like 1

  21. On ‎28‎/‎05‎/‎2018 at 03:53, Knighty2112 said:

    Here’s a graphic to make it clear. This is looking down on the orbit of the earth and moon from the northern plane of the solar system.

    D1088C29-C63B-4099-A98C-D23CBFABA1C8.thumb.jpeg.56b482f184d2ddb67a2cec3054228f49.jpeg

    If the Earth were stationary it would look like that, but since Earth is also in motion around the Sun, the Moon would actually appear to weave "in and out" , as in these pictures:

    moon orbit.jpg

    moon_s-shaped_orbit.gif


  22. Can I join the club? My EQ6-R Pro arrived today, along with a Stellarvue FG50 guide scope which I'll install on my GT81. 

    I have an AVX that I really like and unlike some, get good service from. I'll keep it for mainly visual, and grab-n-go service. I may even image with the GT81 on it, but the EQ will definitely get the Edge 8 for AP. Plans are also to use a tandem dovetail saddle and use the GT81 as a guide scope for the Edge.

    All I've done so far is unbox the Skywatcher and put it together, stand back and admire it. I've looked through the Synscan manual, looks like there's quite a few differences (none too serious, though) between it and the Nexstar/Starsense HC's and operations. Hope I get a few decent nights this week and weekend, I'm headed to the Green Bank Star Party mid-July, and want to be familiar enough with it so I don't waste half the night setting it up. One of my clubmates bought one of these mounts a couple of months ago and has been doing some fantastic AP with it and a f/7 102 APO. I fell in love with it immediately; he's going to tutor me in its finer points.

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