Question about Vivitar Viv-tel-76700 75x/350x Reflector Telescope

Open Question

How to use my telescope.I have a Vivitar 76700; came with a Barlow Erecting Lens 1x5 and Barlow 3X and 2 eyepieces. The eyepieces are SR4mm and H8mm. I have no idea what pieces go with what. Please ad

I have a Vivitar 76700; came with a Barlow Erecting Lens 1x5 and Barlow 3X and 2 eyepieces. The eyepieces are SR4mm and H8mm. I have no idea what pieces go with what. Please advise..Thanks, Joe

Posted by on

Ad

2 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya Expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to an Expert (only for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad

SOURCE: vivitar 76mm reflector teles.76700 barlow lens 3x

No the barlow increases the magnification by 3 TIMES for any eyepiece --
this will be too much for that small 76mm telescope.

Magnification is the least important quality of a telescope. Aperture and quality ioptics are much more important. I usually never use a barlow -- just the straight eyepieces in various mm sizes.

Read my tips on my profile page.

Posted on Feb 04, 2011

Ad

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

About my tasco 46-060675 D=60mm F=900mm come with 3 eye lense 1(sr4mm) 2 (k10MM) 3(k25MM) and two tube 1(1.5x erecting eyepiece) 2 (3xbarlow lense


The different eyepieces are to give different magnifications. This is worked out by dividing the focal length of the telescope, f = 900, by that of the EP. So the 25 mm Kellner (that is the type of optics in the EP) will give 900 / 25 = 36 times magnification.

The erecting eyepiece is used for terrestrial viewing. Normally with an astro telescope everything is upside down as that does not matter when looking at a star. So when you want to look through someone's bedroom window you use this.

A Barlow lens is an add-on magnifier. If you add this onto any EP (it normally fits between the EP and the scope) it will increase magnification x 3.

There is a practical limit to what any scope will deliver, governed by its aperture (the size of the front lens) and for your scope this will be about x 120 magnification. Beyond that the image becomes too dim and fuzzy. This means that your 4 mm eyepiece ( x 225 magnification) won't be much use. It will be hard to find the object you are trying to observe, it will be hard to focus, and the image will wobble around. Nor is your barlow lens much use either I fear.

You might consider another eyepiece around 18 mm to give a nice spread. A Plossl type is good. If you get serious about astronomy, I think you will immediately want a better scope after using the Tasco.

Mar 23, 2015 | Tasco Optics

1 Answer

How to use my telescope to stare better at moon, venus ...etc


1. Download stellarium at stellarium.org (free) This will tell you where to find the planets.
2. Do not use the erect image eyepiece for astronomy, It is for terrestrial viewing only.
3. Buy a moon filter. They are inexpensive ($12 at Agena Astro and others)
4. Huygens (H20, H12.5) are VERY cheap eyepieces,They have narrow field of view and low contrast. Purchase a good plossl or better eyepiece, you will really see the difference.
5. The SR4 (symmetrical Ramsden) is another cheap eyepiece. Avoid eyepiece designs that were invented in the 1700s. See item 4 above.

Mar 16, 2013 | Optics

1 Answer

No manual need advice on attachments


These are lenses of varying power, or magnification. The SR4 is a 4mm Ramsden, which theoretically will give high magnification. The H20 is a 20mm Huygens, less magnification but much more useful.
As magnification is increased, the image gets more blurred, and the object (like a star) becomes very very difficult to find and keep in view. I would throw the SR4 away.
the 1.5x erecting eyepiece is a terrestrial viewing eyepiece of x1.5 magnification, which shows an image right way up, and 50% closer.
The 2x Barlow is a tele-extender which halves the focal length of an eyepiece and doubles its magnification. It is mounted between the eyepiece and the scope. A 15mm eyepiece becomes a 7.5mm when used with the Barlow.
You will probably use the 20mm and 15mm mostly by themselves though.
Here is further reading
http://www.rocketroberts.com/astro/first.htm

Mar 29, 2012 | Optics

1 Answer

What do you use the barlow lesns for?


The Barlow lens goes between the diagonal and an eyepiece. It doubles (2x) the magnification of the eyepiece used.It does this by halving the f/ ratio of the scope.
Eyepiece alone gives 35x; barlow with eyepiece =70x.

Note: this scope comes with an erecting eyepiece and is NOT suitable for atronomy use (other than perhaps the moon)

Mar 19, 2011 | Tasco Specialty 301051N (100 x 50mm)...

1 Answer

Vivitar 76mm reflector teles.76700 barlow lens 3x eyepiece is to small for it.is there a reducer for the barlow ?kit came with two 3x barlow.same size


No the barlow increases the magnification by 3 TIMES for any eyepiece --
this will be too much for that small 76mm telescope.

Magnification is the least important quality of a telescope. Aperture and quality ioptics are much more important. I usually never use a barlow -- just the straight eyepieces in various mm sizes.

Read my tips on my profile page.

Feb 03, 2011 | Vivitar (1607225) Telescope

1 Answer

Just assembled 76700 Model Vivitar Telescope, not getting an image through the viewer.


Put the diagonal into the focuser and then put the eyepiece that has the largest number written on it into the diagonal. DO NOT USE the 2 x barlow if you have one. Take the lens cap off!

Practice focusing on a distant object during the day time by slowly turning the focuser knob right and or left until you get a sharp image.

Jan 15, 2011 | Vivitar (1607225) Telescope

2 Answers

We have a vivitar reflector tel 76700 not sure in assenbly of eye piece


Just put the eyepiece with the largest number written on it into the focuser. Take the scope outside during the day time and practice focusing on a distant object.

Dec 28, 2010 | Vivitar (1607225) Telescope

1 Answer

We have a refractor AZ2 holder (the only name we have.) No manual, several lenes, but how to put them together??? The lenses are SR4mm, H12.5mm, 1.5X erecting eyepiece & 3X Barlow Lens. Hope you can...


The 3 x barlow will be useless for this small telescope.

Put the 1.5 x erecting PRISM into the telescope and then put the eyepiece with the largest number written on it into the erecting prism. This is your lowest magnification.

Take the scope outside during the daytime and practice focusing on a distant object. Turn the focuser knobs slowly until the object comes into sharp focus.

Aug 07, 2010 | Optics

1 Answer

Upside down images


ALL astronomical telescopes show upside down images it is normal. Put the eyepiece with the LARGEST number written on it into the diagonal. Do NOT use the 2x barlow it is too much magnification for that small aperture telescope.



www.telescopeman.org
www.telescopeman.info
www.telescopeman.us

Jan 05, 2008 | Bushnell Voyager 78-9440 (440 x 12.5mm)...

1 Answer

What lens do i insert into scope to view the moon


The moon is big so use the 25mm. The Barlow will have a multiplication marking on it 2x 3x etc. A 2x Barlow lens will effectively double the power of the eyepiece you are using. Do not use the erecting eyepiece for anything other than land viewing. Erecting eyepieces generally reduce the amount of light reaching your eye and thus reduce brightness of the faint objects in the sky.
So basically just place the 25 mm lens in the focuser and point the scope at the moon and you will be amazed at what you can see and how bright it is.

Dec 30, 2007 | Tasco 350x50mm Refractor Novice Telescopes

Not finding what you are looking for?
Vivitar Viv-tel-76700 75x/350x Reflector Telescope Logo

Related Topics:

135 people viewed this question

Ask a Question

Usually answered in minutes!

Top Vivitar Optics Experts

Joe Lalumia aka...
Joe Lalumia aka...

Level 3 Expert

3186 Answers

kakima

Level 3 Expert

102366 Answers

Cindy Wells

Level 3 Expert

5218 Answers

Are you a Vivitar Optic Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...