Does this exist?

[emadmoussa]

I was wondering if such accessory existed. Some sort of transparent glass screen to sit on the front of the telescope. Something like the cap, but will let you observe without removing it and at the same time prevents your lenses from dust!

[JamesF]

It would be possible, I guess, but it would probably have to be a multi-coated optically flat piece of glass. Even for your 80mm OTAs I don't think that would come very cheap.

James

[emadmoussa]

Yeah, I can imagine. A transparent 1.25" coated filter is at least £15...imagine if I find one for the 152mm ...

I was just curious..

[Steve Ward]

And what do you put in front of that to stop IT getting dusty . . .

You need to stop worrying about a little bit of dust and get out there . . .

[Andy_E]

Photographers use them all the time. They often get called UV filters etc, but as mentioned they don't come cheap. the 77mm on my 400mm lens cost around £60. the only problem is they are threaded for camera lenses... so some DIY would be needed to adapt it for astro use. I'll have a quick scout round and post a link if I find something.

[emadmoussa]

And what do you put in front of that to stop IT getting dusty . . .

You need to stop worrying about a little bit of dust and get out there . . .

Lol, I hate dust anyway

Yesterday I received my 2" skywatcher 2x barlow - great piece of kit. Took it out of the box and then unintentionally touched the lens...now it has my greasy finger prints...which is awesome ...NOT. It turned into a microscope now. I probably need to order some cleaning kit

[JamesF]

I agree with Steve. Get out there and use it. And when it gets dirty there's Baader Optical Wonder fluid and cloth.

James

[Steve Ward]

" I hate dust anyway "

Sad . . . .

[Andy_E]

Sorry for the double post... something like this http://www.wexphotographic.com/buy-hoya-82mm-shmc-pro-1-digital-uv-filter/p1019518 ... not sure if it would hamper light transmission a tad though.

[emadmoussa]

I agree with Steve. Get out there and use it. And when it gets dirty there's Baader Optical Wonder fluid and cloth.

James

That's what I'm doing...

It's nice to find some leaves inside your tube, is it?

[JamesF]

" I hate dust anyway "

Sad . . . .

I believe it was Quentin Crisp who said that he never cleaned, as after the first three years it built up in drifts in areas you never use, like snow.

James

[Cath]

I believe it was Quentin Crisp who said that he never cleaned, as after the first three years it built up in drifts in areas you never use, like snow.

The blue rinse master

[Cath]

I was wondering if such accessory existed. Some sort of transparent glass screen to sit on the front of the telescope. Something like the cap, but will let you observe without removing it and at the same time prevents your lenses from dust!

Something like an SCT front corrector plate I spose, only flat?

The one on mine looks perfectly flat to me, but it does hold the secondary mirror in place without spider veins.

[Steve Ward]

And he was right . . .

[ronin]

They are termed Optical Windows. Edmund Optics sell inexpensive float glass optical windows, just not all the big. Prices are a bit odd in that the biggest is less then the one below it in size, but it is still just 2" diameter.

They make a 10" diameter one for £56 (I assume you then add VAT) that is AR coated, doesn't specify the glass but as it is not in the float glass bit I assume something better.

They may make you therefore a 10" float glass one.

Edmund Windows

After that you need a holder for it to fit the scope.

Perhaps the person that makes components for FLO could be approached?

There will be others that produce optical windows and maybe less the Edmunds, have a search around for places. They are not uncommon as they are used to protect the expensive stuff from grubby fingers.

[E621Keith]

This stuff?

http://www.firstlightoptics.com/protection/baader-turbofilm-clear-127m-x-051m.html

Basically a sheet of Baader solar film without the solar filtering part

This guy use it on his Planewave CDK to potect it from pollen

http://www.celestron-nexstar.de/planewave/planewave_geissinger.htm

[JamesF]

With a piece that big you could wrap the entire telescope in it

James

[Pig]

Naughty naughty dust Cant you just run the Dyson over your expensive equipment before you use it ?

[ollypenrice]

This is a non problem. Look through your optics, not at them. Adding another layer of glass is the last thing you want to do. Dust is neither here nor there and neither is a fingerprint. I clean EPs all the time, though carefully, using proprietory lens cleaner. Objectives I might clean once every six months - and this is in commercial use.

Olly

[Adrian Condon]

Hi,

I agree with Olly, I would like to add an observation, the more glass you have the more dew you attract.

From my experience, dust does not effect your viewing, but dew kills it dead!!!

I know people who spend a fortune on quality camera lenses, only to save money using a cheap filter.

I get very little dust on my eyepieces because when not in use they are kept in little plastic canisters

inside a Maplin metal flight case.

The object is to view the night sky not any dust that may be apparent in the daylight.

Trust you will have clear skies......

Cheers

Adrian

[Zakalwe]

Photographers use them all the time. They often get called UV filters etc, but as mentioned they don't come cheap. the 77mm on my 400mm lens cost around £60. the only problem is they are threaded for camera lenses... so some DIY would be needed to adapt it for astro use. I'll have a quick scout round and post a link if I find something.

I use UV filters on all my lenses. To be fair though, a camera lens is far more likely to get knocked and or scratched in use than a scope lens, which is why I have them on my lenses.

[Steve Ward]

Sensible thing to do , I do the same thing ,

My point is that the frontmost element of your set-up....... IS GOING TO GET DIRTY !!!....... get some Wonderfluid and keep your fingers off the glass ....

[emadmoussa]

I use UV filters on all my lenses. To be fair though, a camera lens is far more likely to get knocked and or scratched in use than a scope lens, which is why I have them on my lenses.

If I had a nickel every time I knocked the telescope...darkness + too many connections and pieces = forgetting stuff and thus accidents

[Peter Drew]

There is a world of price difference between a protective cover glass and an astronomical quality opical window of any significant size. Cameras normally work at much smaller diameters than telescopes and at lower magnifications so super quality is not needed. Using a high quality coated optical window would present the same level of care as the objective, so not much point really.

[Pig]

This topic is irony at its best We use the scopes to look at nebulae etc...... are they not dust clouds