wookie1965
-
Posts
8,807 -
Joined
-
Last visited
-
Days Won
6
Content Type
Profiles
Forums
Gallery
Events
Blogs
Posts posted by wookie1965
-
-
Take a picture of your focuser if you can as I know the Skywatcher focuser's have a screw to hold focus so no matter whether you try focus one way or another it will still be the same.
This would need to be loosened off then the focuser will do its job.
-
Just one thing if you are using Vega you will not mistake this for any other outlining stars as it is very bright. As the summer triangle is up I use Vega and Deneb.
-
1
-
-
3 hours ago, Trikeflyer said:
Got mine the other day 😀 Brilliant. Used it the other night when it was clear. Best thing ever is that it’s organised by constellation and has SAO numbers and magnitudes and separations😁. With Goto it Makes finding doubles as easy as shooting fish in a barrel 🤣 If doubles are your thing then this is a must have. Wished I’d found it earlier. I also decided to use the etc 125 mak which I had kind of fallen out of love with a bit. Had a fab night of observing doubles. Back I love with it now. The other great thing about the book is that it has showpiece stars by constellation so you can really hone in on the best ones. Paul, you’ll really love this beautiful book.
steve
have been using Hass and got a load of SAO numbers from Eagle Creek and a very good friend on here but like you said this has transformed my double star observing.
-
1
-
-
Loads of SAO numbers in for double stars.
-
6
-
-
Booked Friday and Saturday
Paul
-
This is mine when I had my 200p on the mount very rarely went near legs except pointing straight overhead which I did not do after it caught the legs once. If you have android download this app https://play.google.com/store/apps/details?id=com.RapidoDroid.synscaninit2&gl=GB
-
-
I have seen one of these in action brilliant mounts only problem I see is if you use long fracs like me. I need a extension on my EQ5 mount to clear the tripod legs. If this could be addressed I would seriously consider getting one.
-
2
-
-
May get there this year health permitting.
-
No idea how good or bad these are.
-
On 28/10/2010 at 14:15, lunator said:
I have been meaning to do this for a while.
Here are a selection of links to useful websites for the double star fan.
Cheers
Ian
SkyandTelescope.com - Double Stars
Washington Double Star Catalog - Current Version
Double Star Club Introduction | The Astronomical League
Eagle Creek does not work now have to go here http://web.archive.org/web/20170419050003/http://astronomy.eaglecreekobservatory.org/doubles/
-
1
-
-
Another cracker is the Garnet Star, Mu Cephei in the constellation Cepheus varing in brightness from magnitudes 5.0 to 3.7. Give that a look.
-
1
-
1
-
-
Fabulous star one of my favourite stars I revisit whenever I can.
-
1
-
-
1 hour ago, vlaiv said:
You know how the saying goes: "one man's trash is another man's treasure"
I found that website to be extremely useful tool once you understand it's limitation and application. Readings with SQM/SQM-L will certainly vary across nights and will be different to map as map probably represents annual average value, or at least average value of recording times (which might or may not be uniformly dispersed throughout the year). VIIRS data is actual recording taken via satellite of ground sources total illumination. Atlas data represents numerical approximation of sky brightness made by integrating ground sources illumination and atmospheric scatter - I think it is very clever that they managed to get it to such level of precision.
One needs to distinguish sky brightness to other things that impact visual astronomy. Transparency, both local and high altitude can have significant impact even in very dark skies - this can make one observing site preferential to another one. SQM readings on particular night might vary significantly to this map. Amount of water vapor in the atmosphere can contribute to light scatter quite a bit, light sources are very dynamic, lights get turned on and off, it even depends on traffic density and road conditions if you have significant road network near by. Dry road and wet road have different reflection properties. Snow increases light pollution quite a bit. So many things impact this that it is quite a miracle that such map works and works so well - within mag 0.5 in most cases - that is up to 63% of base value.
Brightness and Artificial brightness are probably ground luminosity recorded by satellite. First being just natural sky glow reflected of the atmosphere and ground, and second artificial lights on ground - what we think of when we say light pollution.
SQM is magnitude per arc second squared and can be thought of as: if every arc second x arc second (square with sides 1 arc second) contained a star with apparent magnitude of XX without any other light sources in the sky it would be as bright as sky is now. Just for comparison, Vega is 0 magnitude star, and Jupiter has about 1600 arc seconds squared of "angular surface" when largest. Every 5 magnitudes is x100 less light, so mag20 star is 100,000,000 times fainter than Vega (hope I got number of zeros correct
). It should consist from natural sky brightness (zodiac light, milky way, stars ...) + atmospheric scatter of artificial light from the ground. When there is no artificial part, natural brightness is at 22mag.
This number is more meaningful to imagers than observers because it can be used in SNR calculations. It is also useful to guess visibility of some faint objects if you compare that to surface brightness of those objects - this is what Contrast Index in Stellarium for example represents:
Ratio of brightness of target to brightness of background sky. Surface brightness in Stellarium is given in magnitudes per arc minute squared, and for conversion one needs to
subtractadd 8.89 to get magnitudes per arc second squared. Do be careful with surface brightness in stellarium - it is average value and real value can vary quite a bit - think galaxy core vs outer parts - core is way brighter than outer parts.Ratio from above info represents how many times that particular sky is brighter than natural unpolluted sky in zenith.
Altitude and coordinates are self explanatory, me thinks.
Thank you for the explanation looking at it means ive got pretty shoddy skys.
-
what do the numbers mean?
-
Thank you just found once you have located your position if you click on print it opens a page in the browser and you can take a screenshot from there. Now what do all those numbers mean.
-
1
-
-
Sorry for my ignorance I have tried all the overlay buttons and different combinations and cannot get the Information everybody else is. Can some kind person give me a walk through please
-
Sorry I will not make it sadly my back has rendered me nearly house bound.
I'm on morphine patches and injections every 4 months.
-
1
-
-
Here are my Revelation 10x42 waterproof roof Prism binoculars.
-
2
-
-
9 hours ago, Ricochet said:
I have a laser collimator that looks like this.
The instructions below are valid for this type of collimator, but will probably also be useful for other designs.
- Internally, there is a smaller metal cylinder that comprises the laser diode and the battery compartment. This cylinder is quite stiffly pivoted at the bottom end and the three screws at the top simply push against the sides of this cylinder to adjust the position. The pivot in mine is stiff enough to hold the cylinder in a fixed position without the adjustment screws being in use. You can use this to start your collimation procedure with the screws backed out.
- Some sort of target or grid on the wall you are pointing the laser at might be useful so that you can more easily tell how far off centre you are at any point.
- When collimating start with all the screws backed out so that they are not touching the internal cylinder. Rotate the collimator until the laser dot is at the lowest point of the circle traced by the laser. If you tighten the screw that is now top-most it will bring the laser dot upwards. Tighten the screw a touch and rotate the collimator again until the laser is at the lowest point in the new circle. Tighten whichever screw is now nearest the top. Repeat this procedure until the laser is collimated. You will probably find that you are only tightening two of the screws. Once you have the laser collimated carefully snug up the screw that you haven't really touched to lock the laser in position.
- Don't tighten the screws too tightly as the internal cylinder is quite delicate and you could either deform the cylinder or cut through the plastic film that insulates if from the outer body and create a short circuit. (This might not apply if your adjustment screws push against a solid part and not the sides of the battery compartment like mine.)
Edit: Even with my laser collimated I mostly use a sight tube to collimate the secondary mirror, with the laser just to check/tweak. To collimate the primary mirror I use the barlowed laser method (just put a barlow between the focuser and laser). This turns the laser into a torch which illuminates the central part of the mirror and the centre spot. You then collimate the primary by centring the shadow of the primary spot on the collimator face. This method reduces the effects of inaccuracies in the collimation of your laser and secondary mirror.
Going to try that on mine much easier to understand thank very much.
-
I have two threw the first one in the bin no matter what I did could not get it right.
The second one a friend well more advanced than me collimated it for me but he even said done the best he could and it is only slightly out, I know you won't like this but I then check with a Cheshire/ sight tube.
-
1
-
-
Mine went through to 18% then knocked off could not get it working until son took it home went straight through
-
Those cheap adapter cables dont work I know at my cost luckily son had the port on back of an old computer and did mine.
-
My Meade with Skywatcher dual speed focuser.
-
11
-
). It should consist from natural sky brightness (zodiac light, milky way, stars ...) + atmospheric scatter of artificial light from the ground. When there is no artificial part, natural brightness is at 22mag.
Is it okay if the center spot isn’t a doughnut?
in Getting Started Equipment Help and Advice
Posted
I used a paper reinforcement ring on my 8" when I cleaned it as been told the one on may wash off worked brilliantly.