roryfirth Posted January 6, 2011 Share Posted January 6, 2011 Hello all Looking to purchase a decent beginners telescope and have come across the SkyWatcher for around £190 which seems like a good deal. I want to be able to take pictures using my Canon 5D, is there an adapter available and is this a good choice to use with a webcam through my laptop?Thanks in advance. Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted January 6, 2011 Share Posted January 6, 2011 Hi Rory"Dobs" are not really the best scopes for taking images with because they are manual and you have to move them up/down/left/right. For imaging you would be better off with something on an equatorial (EQ) mount.When people talk about Dobs...they are infact referring to the mount being a Dobsonian mount. The scope on the mount is a standard Newtonian reflector.So a Newtonian reflector on an EQ mount would be better for imaging. The EQ mount will enable you to track stars so when you image them you do not get trails in your image.They will remain as points of light.The SW Explorer 130P is a popular choice for first scopes. It is held in high regard.http://firstlightoptics.com/proddetail.php?prod=sw130pBut dont take my word. There will be others who can better advise you. Link to comment Share on other sites More sharing options...
John Posted January 6, 2011 Share Posted January 6, 2011 As Paul says, plus I'm not sure you can bring a DSLR to focus on some scopes without either repacing the focuser with a low profile one or moving the primary mirror - not sure about that so perhaps someone else can confirm ?. Link to comment Share on other sites More sharing options...
roryfirth Posted January 6, 2011 Author Share Posted January 6, 2011 Thanks Luke, the SkyWalker does look like a good option to start with. I see on the website there is a 130 and a 130P option, apart from price difference of £40 I can't see much difference, if anything the 130 seems to better equiped than the more expensive 130P? Link to comment Share on other sites More sharing options...
rowan46 Posted January 6, 2011 Share Posted January 6, 2011 the P has the better optics Link to comment Share on other sites More sharing options...
roryfirth Posted January 6, 2011 Author Share Posted January 6, 2011 Ok, novice question, how much better are the optics and what difference do they make? Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted January 6, 2011 Share Posted January 6, 2011 The 130P has a parabolic big (primary) mirror. The design of the parabolic mirror means that light is gathered from across the mirror and is concentrated towards the middle of the mirror where it is picked up by the smaller secondary mirror. The ordinary 130 model has a flat mirror and while light is also gathered from across the whole mirror, it is not concentrated towards the centre as much. This means that the image you see will not be as good. It will be dimmer and not as sharp. It will still be good but not AS good.Think of the mirror on a visual telescope as the same thing as the dish on a radio telescope. Same principle....................anything (light or radio waves) are gathered and concentrated at the centre. Also have you ever noticed how much better your hearing gets if you cup you ears with your hands?Same principle once again. The sound you hear is being concentrated into your ear by the "parabolic" shape that your hands make. Owls have this parabolic design on their heads/eye sockets to help them see better.It the principles of parabolic's work in nature, then they surely work in mechanics.So basically YES the 130P model of the scope is better then the standard 130 model.Hope this helps.The model you see for about £190 also has a Go-To system installed. So it is a parabolic mirror and Go-To. Its a very nice scope for a very good price. Some people like to use Go-TO to help them find objects. Others prefer to use a manual scope to find objects. That part of the setup is a personal thing. You have to decide which you like best.Sorry i nearly forgot. To attach your camera to the scope to enable you to take pictures you will need to buy an adapter called a "T-ring".It still puzzles me why it is called a T-ring when it is clearly round and looks nothing like a T. Link to comment Share on other sites More sharing options...
Suzpaz Posted January 6, 2011 Share Posted January 6, 2011 It still puzzles me why it is called a T-ring when it is clearly round and looks nothing like a T.Original Manufacturer was Tamron Link to comment Share on other sites More sharing options...
rowan46 Posted January 6, 2011 Share Posted January 6, 2011 Original Manufacturer was Tamron thanks for that you learn something new every day Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted January 6, 2011 Share Posted January 6, 2011 Original Manufacturer was Tamron Never met him,LOL. Thanks for that bit of info. Link to comment Share on other sites More sharing options...
Suzpaz Posted January 6, 2011 Share Posted January 6, 2011 Tamron - Wikipedia, the free encyclopediaMore (usually called the T-Mount if you do a CTRL+F) Link to comment Share on other sites More sharing options...
irishbloke Posted January 6, 2011 Share Posted January 6, 2011 As far as I know it's parabolic vs spherical not flat. A flat primary mirror wouldn't work. A spherical, as in the right size of ball would be in complete contact with the mirror does focus light towards the secondary mirror and eyepeice but doesn't focus it just right. The parabolic mirror has the centre part ground a bit deeper that sorts the focusing issue better allowing you to see things sharper.Brian Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted January 6, 2011 Share Posted January 6, 2011 As far as I know it's parabolic vs spherical not flat. A flat primary mirror wouldn't work. A spherical, as in the right size of ball would be in complete contact with the mirror does focus light towards the secondary mirror and eyepeice but doesn't focus it just right. The parabolic mirror has the centre part ground a bit deeper that sorts the focusing issue better allowing you to see things sharper.BrianSpherical. Yes indeed you are right. I just said "flat" because its easier to spell,LOL.Thanks for correcting my LAZY error. I didnt mean for my comment to be in anyway wrong or misleading. I covered the benefits of parabolics though, so thats a good thing. Link to comment Share on other sites More sharing options...
russ Posted January 7, 2011 Share Posted January 7, 2011 Hello all Looking to purchase a decent beginners telescope and have come across the SkyWatcher for around £190 which seems like a good deal. I want to be able to take pictures using my Canon 5D, is there an adapter available and is this a good choice to use with a webcam through my laptop?Thanks in advance.The 150PL is a great scope for webcam planetary work but you'll need a driven EQ mount for the tube to have a decent stab at imaging. That said, when i started with the imaging with an XT10 dob, i used to let the object drift across the field and capture a short movie and then stack. It was well fiddly though, hair pulling frustrating.With the 5D you'll have a few other problems too. The main one will be horrendous vignetting, really horrible. The Skyliner only has a 1.25" focuser and the 5D is a full frame sensor. Vignetting is pronounced on an APS-C size sensor, so you can imagine just how bad it will be on the 5D. You could replace the focuser but that's more expense and the scope won't be setup to fully illuminate the sensor anyway.A much better bet would be the 150PDS. This has been setup with imaging in mind from the outset but still brilliant for visual. But then there is the cost, a lot more than £190. Well actually the 150PDS is only £183 but you'll need a mount to go with it. Which needn't cost a lot if you are prepared to buy secondhand.Reflectors - Skywatcher Explorer 150P DS OTA Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.