I have a 3x barlow lens that I can't see anything out off. This telescope was given to me. The 22x lens works fine. There is a tube that goes with the barlow lens, not sure what this is. Thanks for any help.
SOURCE: i dont know how to use my barlow lens
I use a barlow lens quite a bit with my telescope. It is usually inserted before the diagonal if you use one or before the eyepiece if you don't. The barlow lens for your telescope will double the power of the eyepiece used.
However, despite what the manufacturer claims for your telescope things will look quite poorly if you try to view at 180 power. Generally you'll get the best images by using 50x for each inch of your objective lens. For example, your telescope has a 50mm lens. That's roughly 2 inches. 2 inches times 50x gives you a maximum useful power of 100x. Depending on the viewing conditions you may be able to exceed this or not even reach it. Things will look blurry and dim when you try to use too much power.
Your power or magnification is calculated by dividing your telescope focal length which is 360 mm by the eyepiece focal length. You have two eyepieces with focal lengths of 4mm and 20mm. If we divide 360mm by 20mm we get 18 power. If you add a barlow to that you get 36 power. Dividing 360mm by 4mm (no barlow) we get 90 power. That would be your maximum useful power.
Therefore, you should be able to used the 20mm eyepiece with or without the barlow but the 4mm should only be used without the barlow.
I hope all of the math wasn't confusing.
-jodair
Posted on Mar 25, 2009
SOURCE: Bushnell Deep Space Series 525x 78-9500
The erecting prism can be used for both terrestrial and star gazing-- put it innto the scope first.
The 3x barlow probably will NOT be very useful... it triples the power of any eyepiece. Your small scope cannot go much over 100 power-- before the image degrades.
Put the eyepiece with the BIGGEST number written on it into the erecting prism which you previously stuck into the scope... now go outside during the daytime and practice focusing on a distant object.
The bigger the number on the eyepiece the LOWER the magnification.
Posted on May 16, 2009
SOURCE: Set up a Jason 307 Explorer Telescope?
Jason and Bushnell are the same company. Here is a list of the manuals. Find your telescope-
http://www.opticsplanet.net/bushnell-warranty.html
Look down the web page.
Posted on Aug 30, 2009
SOURCE: I don't know how to work my telescope I don't
It multiplies the normal magnification of each eyepiece THREE times! In your small telescope you will probably never be able to use it. Magnification is the least important quality of a telescope.
Use the eyepiece with the largest number written on it, which is your LOWEST magnification. Practice focusing on a distant object during the day time. At night the moon should be your first target.
Posted on Nov 12, 2009
SOURCE: I have a 3x Barlow telescope that is completely
There is no such thing as a 3x barlow telescope. A barlow is a small accessory that multiplies the magnification of any eyepiece.
This is a barlow-
http://www.agenaastro.com/GSO-1-25-2x-Barlow-Lens-p/obar-gs-gs2bl.htm
Posted on Jun 01, 2010
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Hello first things 1st your barlow lens should be about 2 - 4 inches in length it consists of an eye piece screwed on to a tube,this barlow goes in the 1.25 inch hole (visual back) then your 22mm eye piece fits into the barlow,One thing will stop this from working is if your telescope is exceding its maximum useable magnification. In other words trying to magnify the image too much. You can calculate this by dividing the focal length of your telescope by the eyepiece, In this case 22mm. For example 900mm focal length divide 22mm eyepiece = 40x Magnifcation then include 3x barlow = 120x mag which should be fine with your telescope.Try screwing the tube onto the barlow then inserting the eyepeice into the barlow. Hope that helps Good Luck
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