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Secondary spun!!!!!!!!! my sn8 secondary spun in the corrector plate !!!!?????how does this happen???!!!not tight enough to even adjust the mirror without thi happening!! how do ya re orient this properly??????????

Posted by astronig on Oct 10, 2007

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Full text of "Sky and Telescope 1989-07-pdf" - Internet Archive


Full text of "Sky and Telescope 1989-07-pdf" See other formats ...
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Calaméo - ENCICLOPEDIA DE OPTICA(INGLES)


John Gregory had suggested in 1663 that a focused image could be formed by a curved mirror without ... secondary mirror ... mirror and an aspherical corrector plate ...
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Full text of "Sky and Telescope 1993-10-pdf" - archive.org


Full text of "Sky and Telescope 1993-10-pdf" See other formats ...
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3527403205 - pt.scribd.com


Since mirrors do not transmit light, the mirror substrate can be any suitable ... moving the secondary mirror in order ... mirror and an aspherical corrector plate
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3527403205 - Scribd


Since mirrors do not transmit light, the mirror substrate can be any suitable ... placing a secondary mirror with ... mirror and an aspherical corrector plate
Read More At : www.scribd.com...

Suggested Questions And Answer :


The image through my Celestron Astromaster 114EQ is at an angle, ie SW/NE orientation. Can this be fixed by collimating the telescope?


Hi David I would try calling and leave a call back number with them.
Read More At : AstroMaster 114EQ (100 x 114mm) Telescope...

Lube stain on Secondary mirror on CPC 1100


Probably lubricant out-gassing which can collect than drip. Your choices are to contact Celestron service or do it yourself. DON"T PANIC! It is not that hard if you are brave. 1. Use a piece of masking tape on the corrector to the side of the housing.slice it carefully where they meet. This will insure correct alignment with the primary when you put it back together. (Correctors are sorted then oriented to,(as the name says) correct the primary.2. Remove the corrector plate. Mark any shim locations with a marker on the outside of the corrector plate (remove after re-installation)3. Make a solution of 50% distilled water and 50% isopropyl alcohol. (97% pure or better- I use 99% pure alcohol) 1 drop of dish detergent may need to be added,depends on the stain.4. Rinse the secondary until grease is gone. Do not rub mixture on mirror, just keep rinsing.5. Rinse with pure distilled water,gently stand corrector up to dry. 6. Assemble the scope. Use the same water/alcohol mixture to clean up the outside of the corrector. Dampen cotton balls and wipe with VERY light pressure.Wipe once, throw the cotton ball out and use a fresh one. Do not make the cotton balls too wet, you don't want moisture to get under the corrector.7. If the stain is really tough, acetone may be used without damage to the mirror surface.8. Use surgical gloves to avoid fingerprints.9. Lots of towels at work area in case the corrector slips out of your grip.10. If you put it together correctly, minimum collimation will be required. There have been a number of these problems cropping up lately, I think Synta is using inferior grease now.If you are really brave, clean the old grease off and add one drop of lithium grease. Run the primary through focus range a few times to distribute. If you do this, you can later flock the inside of your scope to increase contrast.
Read More At : CPC 1100 GPS (XLT) (70 x 280mm) Telescope...

I recently aquired the bottom part of a Meade Lightbridge 10" Truss Dobsonian Telescope. This includes the Primary Mirror & tube that contains it plus the 3 Struts and not much else. I think I can make myself the Base, but the problem I have is with the top tube that holds the secondary mirror & focuser. I need to know the exact dimensions of this tube that holds the secondary mirror & focuser so I can match this with parts (the secondary mirror & tube, I already have a focuser I can use) I can buy from vendors. Alternatively, do you know of someone with an undamaged secondary mirror & tube for a 10" Meade Lightbridge Truss Dobsonian Telescope willing to sell it? call Ken at 615-832-7464 or e-mail at [email protected] and let me know Ken


Try posting this question on the www.cloudynights.com FORUM, either in the REFLECTORS topic, and or ATM, Optics Topic.Someone will answer you with the exact dimensions You can also post a Free Classified ad there -- a WANTED ad looking for the entire missing top section, Meade "may" also be willing to sell you this.www.meade.com.Clear Skies
Read More At : LightBridge 10 in. Standard (600 x 254mm) Telescope...

My Meade Polaris 60EQ-D Telescope is missing the diagonal mirror.


Here is Meade's manual web page. Find your telescope on the page:http://www.meade.com/manuals/index.html
Read More At : Polaris 60EQ-D (36 x 60mm) Telescope...

Rear mirror I have a telescope which I believe the internal mirror in the base may have been adjusted. Is there a way to test or reset to original, or am i just wasting time. The manual states never to adjust this but try telling my son. I have tried to locate something on this on the net but cannot locate any help. Yours help would be much appreciated


I may be telling you something you already know, but just in case. If your telescope is a newtonian/dobsonian (i.e., long, large tube) then the mirror in the bottom can be adjusted to collimate or align properly. On the other hand, if the top of the telescope has glass over it (refractor telescope) then putting it back into place will be more labor intensive and I wouldnt even try it. Try going to the manufacturers website and asking them. You might post the same question on a telescope forum called cloudynights.com. If you live in a large city, try searching for local astronomy clubs as every astronomy club has some guy there who takes these things apart for no reason just to put them back together.
Read More At : 578x60mm Reflector Luminova Telescopes...

Problem with orion 6" dobsonian mount telescope


The small mirror is usually held on with double-sided foam tape. That tape us used, so the small mirror is not stressed by the metal fittings with temperature changes. Clean the residue from the holder and the mirror, and apply fresh double-sided mounting tape and carefully place the mirror so that the main mirror is viewed from the eyepiece position.
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Another question How about if i buy the celestron 8se from Amazon (the option that includes free shipping) on the address of my friend. All my friend has to do is to check it that it works and ship to my address in france. The following fixed and definite costs would be: -Payment to Amzon for the equipement (USD 1199) -Payment to my friend for shipping to me (via UPS) *The cost in Europe is Euros 1650(including shipping) *The cost from US is approx Euros 1050 (including shipping + insurance and exchange rate based) The following probable cost is the Adouane or cutoms duty. The telescope has 20% VAT (Euros 168) which brings the actual price of the telescope to Euros 1218. Now excise duty doesnt apply on this postal mail. We are left with only one duty i.e., custums duty which is applied on price base+insurance (no shipping cost included). This varies from country to country and product to product. I assume if it reaches to as high as 30% (more than VAT) the total price would be Euros 1500. Now the profit margin seems to range from 50 to 100 euros. So as per my rough guess, if your mail skip the customs (usually happens) then you can have a price advantage of around euros 300 to 400. After all this calculation we need to see what disadvantages might exists. The only main disadvantage is that the warranty rests in USA. So if some thing wrong happens which is beyond the engineering mind of the telescope owner, it is possible that it stands in the room as a piece of junk. The cost of sending back to US and receving back means one problem will simply cost approx Euros 450 (return based). If this risk can be taken, i think there is a point to buy without going to USA. I have googled around and found that most of the single item based postal mails skip the customs and most of the time the VAT as well since it is costly and time consuming activity for the governments to follow each mail. In UK, they charge the customs plus the custom services from the client. Here is the mail translated in english that i recieved from the www.astroshop.de to my recent inquiry regarding price. ******************************************************************************** Hello, and Thank you for your message. The product you want to buy seems to be cheaper in the U.S. that Germany. But it is a false impression. In the given prices, taxes and costs for the customs are not included! It makes a big difference! Please also note that there are other problems if you buy in USA: - If you have a problem with the telescope, you must send it to the U.S. ... And it also has to do with costs for the customs and extremely long lasting delays - In addition, shipping costs are also higher than in the U.S. and `can lasts much longer. In addition, you do not have the same rights and safety regulations, for example, you can not change the products, you do not have 2 years of warranty etc. ..... If you consider these arguments, I think you'll think - like us - that it makes no sense to buy the equipment in the U.S.. Please contact us again if you have more questions or suggestions please ****************************************************************************


You would be better off to buy locally. Try to find a local astronomy club and attend their meetings and star parties. Sometimes the members sell their older equipment at greatly reduced prices.
Read More At : LX90 12 in. UHTC Telescope...

Lost vision The telescope was working fine until I was trying to match the view through the smaller spotting scope with that of the main telescope, and suddenly I could faintly tell I was aimed at the moon by a soft glow alone, but could no longer actually see details nor the usual brightness of it. I've taken the scope apart and cleaned the lenses and mirror. I can see beautifully if I remove the eyepiece, but of course I'm just looking at the mirrors inside at that point. When I replace the eyepiece, all I can see is that very faint glow which, when focused, gives me that funky view of the inside of my own eyeball like when you get your eyes checked at the optometrist's office and they shine that bright light in your pupil. Any idea what's happened here and how I can fix it? Maybe I need a new eyepiece?


Your telescope is a "Newtonian," as such it requires regular "collimation" Collimation the alignment of the optics. The mirrors must be lined up properly for the telescope to deliver a good image to the eyepiece. Your scope sound like it is way out of collimation. My guess is that the diagonal (secondary) mirror has rotated in it's mount. There are three basic tools for collimating a Newtonian the Sight Tube, Cheshire and Autocollimator. To get your digonal aligned correctly you need a sight tube. Rather than spend a lot on these consider making your own and keep an eye on eBay offerings. Don't bother investing in a laser collimator, they simply don't do the job unless you go for the very best. From some help with the collimation process check these links. http://www.astronexus.com/node/6http://www.amateurastronomy.com/collimate.html The 60 page pamphlet "New Perspectives on Newtonian Collimation," Fourth Edition by Vic Menard and Tippy D’Auria runs $10, but if you really want to do it right it's worth the money. HTH, George
Read More At : Deep Space 78-9518 (675 x 114mm) Telescope...

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