Beginner

[dalemc92]

Hi ive just got a vivo700-76 Reflector Astronomical Newtonian tellescope it comes with

erecting eyepiece 1.5x 

Borlow lens x2

Set of eyepieces  20 mm 12.5mm 4mm

Mooon filter 

Which eyepiece do i use first ?

Thanks 

[Peter Drew]

The larger the number on the eyepieces the lower the magnification which is calculated by dividing the focal length of your telescope, 700mm by the number on the eyepiece. Best to use the 20mm first to get used to operating the telescope. Lots to look forward to. Welcome to SGL.  

[rockystar]

yep, start with the 20mm on its own.

[Floater]

Welcome. Enjoy the learning curve.

[alanjgreen]

Try to use it outside in the daytime, aim at a tv aerial , chimney tree or similar.

DO NOT LOOK AT THE SUN!

try the different eyepieces starting with the biggest number (20) , then come down to 12 & 4

you will see how the lower numbers give MORE magnification.

now, try each eyepiece in turn with the Barlow as well - Barlow in focuser, then eyepiece in Barlow. Your 2x Barlow will double the power of each eyepiece that you put in it!

eventually you will be trying to use too much magnification for the aperture of your scope and focusing will become very difficult. ( the 4mm may be too much magnification for this scope so you may have to leave it in the box  )

once you have the hang of it, then you are ready to do it in the dark

The 20 and 12 should work fine and the 20 with the Barlow (20/2=10) should also work fine.

 

20mm Magnification = 700/20 =35x      

12mm = 700/12 =56x

20 with Barlow = 70x (double the 35x above)

12 with Barlow = 112x

 

your scope should take the first 3 ( 35x, 56x & 70x) but 112x may be too much for it. ( the 70mm aperture is just too small for this amount of magnification! )

 

erecting eyepiece is only needed in the daytime, not needed at night! Try with and without in daylight and you will see what it does (scopes have image upside down, which is fine for nighttime. Erecting puts it the right way round which is more useful if you are using your scope in the daytime).

 

just be be aware that the barlow and erecting eyepiece will affect the focus point, so if you run into focus problems ( I cannot focus at all) then try adding or removing these to fix the issue.

 

you may want to note down on paper which combinations work and which don't for your future reference.

 

Alan

 

[RT65CB-SWL]

Hi dalemc92 and welcome to SGL. 

As previously mentioned, start off with the eyepiece with the highest number and work down to the lowest number... ie 20mm ---> 12.5mm ---> 4mm

I would think the 4mm may give to much magnification. You may be better getting an 8mm or 6mm, or somewhere close. Out of curiousity, are the eyepieces 0.965" or 1.25"?  -  1.25" is the default for 'smaller' telescopes. Eyepiece adaptors are available should you wish upgrade later. 

[alanjgreen]

Don't buy anything until you are familiar with what you have.

as a next stage, you may be better accepting that this is a budget beginner scope and instead investing your hard earned in a more advanced scope.

( you could give this one to a young relative who would be overjoyed )

there IS life in THIS scope, and you can use it as a learning experience

it should be fine on the moon.

[laudropb]

Hello and a warm welcome to the SGL. Lots of good advice already given. If anything else puzzles you please ask.

[LukeSkywatcher]

May i just ask?.....

I know what an erecting prism/diagonal is (i use one myself). I'm confused about the 1.5x "erecting eyepiece". I know what a 2x barlow is also.

I'm unaware of an erecting eyepiece (is it prism/diagonal?) that gives any kind of magnification (in this case 1.5x).