What You Will See
How To View It Safely
Why Transits Happen
 
 
   
 
 
 
 

Telescope Viewing

If you have a telescope with a magnification of 50x to 100x, you will be able to see the transit. Be sure, however, that you have the proper filter for it. Only use the filter supplied by the manufacturer or by a manufacturer who makes a filter specifically for the instrument you are using. And it must be a filter that attaches to the front end of the telescope. If you don't have a suitable telescope, you can use binoculars to make a projector.

 
The suppliers of some cheap refractor telescopes supply a welder's glass filter that screws onto the eyepiece. Do not use these! They may heat up and crack as you are looking through the telescope. A proper solar filter always goes on the front end of the telescope, blocking the sunlight before it enters the optical system.  

Do not use this type
of telescope filter:

The Bad Filter

(Click the image to
see a larger view.)

 
By following the instructions above and using a modicum of good sense, you will be able to enjoy transits and solar eclipses.
 
Optical Projection
 
Click here to download a PDF of the Optical Projection & Filter instructions.
You will need the free Acrobat Reader to view this file.

The usual way that you are told to view the sun is by building a pinhole projector. Unfortunately, this method probably won't work for the transit of Venus. Pinhole images are pretty dim and small. They also lack the proper resolution to view the tiny disk of Venus. But there's another projection method that uses a pair of binoculars. Binoculars with 7x magnification will work fine. Higher magnification will give you a better image, but it will be a bit harder to find the sun. Remember, which ever method you use, Venus will appear as a very tiny black dot on the disc of the sun.
 
Do not look through the binoculars!
 


(Click the image for expanded instructions)

1. First, you should firmly fix the binoculars to a tripod. You can do this with duct tape (what else?).

2. Cut out a cardboard shield and tape it to the front of the binoculars with the lenses sticking through holes.

3. Put the lens cap over one of the large binocular lenses or tape over one of the front lenses with duct tape. (You really only need one lens.)


(Click the image for expanded instructions)

4. Use the duct tape to seal any holes that leak light past the cardboard.

5. Point the binoculars toward the sun while holding a piece of white cardboard about a foot behind the eyepiece.

6. It will take a little effort to find the image of the sun. Once you do, you can focus the binoculars to create a sharp image of the sun.

Be careful not to put your hand or anything flammable near the eyepiece! The concentrated sunlight exiting there can cause a nasty burn or set something ablaze!

Now you can watch a beautiful, bright, magnified image of the sun as the transit proceeds. You will have to adjust the tripod to account for the earth's rotation. One possible warning here: You might give your binoculars a cooling break now and then. The eyepiece can become overheated and the lens elements may separate if you leave it focused on the sun too long.

 
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