I have what appears to be mildew on the inside of the glass lens on my Celestron NextStar 8i telescope. Can it be cleaned? I am a very new amateur sky watcher. Jean Atkinson [email protected]

Reset the hand controller and reload the firmware. You will need a special cable available from Celestron to load the firmware. The software is available for free on the Celestron web site.

http://www.celestron.com/c3/home.php



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

Read this:

http://books.google.com/books?id=V3tyCXsCCkMC&pg=PA80&lpg=PA80&dq=align+nexstar+in+southern+hemisphere&source=bl&ots=KIgbgUDdmW&sig=-I26nKahu0-JbPfnkZUrXuW7oX4&hl=en&ei=7gMmTYWBHsaqlAfe6pXEAQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBMQ6AEwAA#v=onepage&q=align%20nexstar%20in%20southern%20hemisphere&f=false

and this

http://www.nexstarsite.com/Firmware/GPSFirmware.htm

Check the focus knob and make sure the small "set-screw" is tight and the knob is just not spinning around on the shaft.

DID you turn the knob enough to focus? Sometimes it may take 10 - 20 full turns.

Finally the focuser is attached to a "rod" inside the tube that moves the mirror back and forth to focus the scope. It could have come loose from the rod?

Instructions for disassembly are here:
http://www.celestron.com/c3/support3/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=2220

and here:

http://www.sciencecenter.net/hutech/misc/focuslk/index.htm this just shows how it works.

First buy a dew shield, this will help prevent dew for some period of time. You may also need to buy a dew heater for the scope. Depends on where you live.

DO NOT leave the scope pointed up toward the sky for long periods of time.

Bring the scope outside at least 1 hour before you are going to use it. This lets the optics reach ambient temperature which will give you better views.

Here is a retailer that sells a dew shield and dew heaters: Bring the scope inside for a day or two and see if the dew "inside" the tube vanishes all by itself, before you decide to open it up. The corrector lens must be reinstalled in the EXACT position it was in before you removed it.

http://www.optcorp.com/

You are NOT in focus. You are seeing the central obstruction in the lens on the front of the tube. Put the eyepiece with the largest number written on it into the telescope. Go outside during the daytime and practice focusing on a distant object.

Once you are focused properly you can see the obstruction.

Read my GOTO scope TIps on my profile page.

You may be able to get that part from Celestron. Call customer service here:

http://www.celestron.com/c3/page.php?PageID=37

You need to contact Celestron or a Celestron dealer:

http://www.celestron.com/c3/page.php?PageID=37

You obviously burned out something inside. Many of these scopes require a proprietary style 12 volt plug with the correct polarity ---

My only suggestion would be to contact celestron and send it in for repair.

http://www.astronomics.com/main/Warranties.asp/catalog_name/Astronomics/category_name/AK9TFU21GCR78LKGXH66AS3XN7/Page/1

look for the instructions and see if there's some sort of lock that you have to undo to make the lens clear

Has the scope been unused for a while? Perhaps the old batteries have leaked or moisture has caused the battery contacts to be tarnished. Try cleaning the battery contacts with a little alcohol and rub with a rough cloth & try again. Can this model use an external power supply? I know with my Meade scope it worked much better with a larger capacity external battery. Also check the cable for any signs of damage or stretching.