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kingneptune8
2003-Aug-06, 08:05 PM
I made an attachment for the end of my telescope to view the sun. And I had a question about it.

I made an attachment that goes over the end of the scope. It's a piece of PVC with welding mask glass over it. I've only used it once, I just made it.
I don't think it will, but... does anyone know if it will damage my eyes when I look at the sun with it? It doesn't hurt my eyes to use it, but I know your eyes can be damaged without pain. :o
This maybe a stupid question, but I'm not taking a gambel when it comes to vision.
If anyone can answer this, it'll really help.
Thanks!

kingneptune8
2003-Aug-06, 09:44 PM
Please help

Josh_imported
2003-Aug-06, 09:58 PM
I remember reading somewhere, sometime on this board that welder's glass of a certain rating is considered safe, but I don't remember exactly which. Try doing a search of the board of "welder's glass sun" and see what you get.

kingneptune8
2003-Aug-06, 10:01 PM
Thanks... I got a fairly dark grade.

If anyone is interested... it works great. Especially at sunset.

JimTKirk
2003-Aug-06, 10:01 PM
Kingneptune8 - Which end is the welder's glass at? How large is the piece? The biggest problem is going to be distortion. The welder's glass is a much lower quality than a normal solar filter. As long as the welder's glass is not at the eyepiece end of the scope, there should be little problem of the elements in the scope heating up. There are several types of welder's glass available, but I'm not sure if they are all suited for solar viewing. I'd rather put my trust in a true solar filter as the poly type can be had for a small amount of cash on EBay (6"x6" under $20). I've seen others here stating they've used a welder's glass for viewing with no problem.

I know I've not really answered your questions, but I hope I've helped a little. :D

Good Luck!

Russ
2003-Aug-07, 03:27 AM
I strongly urge you not to use your home made sun filter with your telescope. Electric arc welder glass rated 14 or higher will adaquately protect your eyes if you look through it with your eyes only.

Telescopes gather more light than just your eyes and focus it in an area about the size of your dialated pupil. For this reason, the welders glass is an inadaquate filter. There are several companies who make filters specifically for telescopes and they are the minimum with which I would trust my eyes.

Again, I strongly urge you to not use welders glass as a Solar filter for your telescope. Jim's Mobil, inc. (JMI), Astronomics and many other companies sell the correct thing for you to use. It is well worth the extra money to save a lifetime of blindness.

kilopi
2003-Aug-07, 04:21 AM
We discussed it before (http://www.badastronomy.com/phpBB/viewtopic.php?p=25346&highlight=eclipse#25346), and I emailed Mr. Eclipse (http://www.mreclipse.com/Totality/TotalityCh11.html#Filter). He's updated his pages, but they're still ambiguous about that.

His webpage (http://www.mreclipse.com/Totality/TotalityCh11.html#Filter) says that certain welders goggles are safe to view the Sun, but not to use them between your eyes and the telescope. He says to use specially designed solar filters on the "front end" of the scope--but he never comes right out and says you can't use welders goggles on the front end of telescopes or binoculars.

dgruss23
2003-Aug-07, 04:28 AM
You definitely should purchase a specially made solar filter if at all possible. I used to have one, but I sold the scope I'd purchased it for. Anyway, that filter let nothing in but a fraction of a percent of sunlight. If you hold one of those things up to a full moon you'll see absolutely nothing - even in the telescope if I remember right. I definitely don't think you want to experiment with anything other than manufactured solar filters - especially if you're hooking it up to a telescope.

kilopi
2003-Aug-07, 04:37 AM
If you hold one of those things up to a full moon you'll see absolutely nothing - even in the telescope if I remember right.
The difference in magnitude between the Sun and the moon is fourteen magnitudes. That's the same as the difference between Vega and Pluto.

kingneptune8
2003-Aug-07, 07:48 PM
Thanks everyone... I think I'll stay away from hooking it up to the end on my scope. I planned on buying a real solar filter anyway. I was just tinkering around, and made one. Glad I asked.

kilopi, thanks for the links

David Hall
2003-Aug-22, 08:30 PM
You can (and should) buy some cheap, mylar-type solar film. Then all you need is a bit of cardboard to make a nice filter with. I just bought a sheet of Baader AstroSolar film myself and plan to make filters for my binoculars as soon as I get a chance. I'm also thinking about making some simple "viewing glasses" like the kind they sell for solar eclipse viewing. When and if I buy a telescope, I'll buy another sheet and make a filter for it too.

Pinemarten
2003-Aug-23, 01:41 AM
I was perusing Dobsonian type 'light buckets' on the net, and they have moon filters listed as an accessory. Are these to prevent eye damage, or do they have another purpose?

kilopi
2003-Aug-23, 08:53 AM
I was perusing Dobsonian type 'light buckets' on the net, and they have moon filters listed as an accessory. Are these to prevent eye damage, or do they have another purpose?
Not physical "damage" exactly. Using a light bucket to dump lunar light into your eye can be painful though--it's that bright. I sometimes use a moon filter even on my 90mm ETX.

Charlie in Dayton
2003-Aug-25, 05:43 AM
I was perusing Dobsonian type 'light buckets' on the net, and they have moon filters listed as an accessory. Are these to prevent eye damage, or do they have another purpose?

'Moon filters' usually screw into the eyepiece of a telescope. They generally have a greenish tint to them to increase contrast between the various areas of the moon, and the standard seems to be that they transmit about 14% of the light to your eye to reduce glare (and the accompanying night blindness). They are excellent for viewing the Moon (and a couple of the planets that share the same optical characteristics -- it will make a difference in viewing Mars, for example). The Moon is not bright enough to cause any permament damage to your eyes. On the other hand, unfiltered viewing shoots the snot out of your night vision for awhile.

Moon filters are totally ineffective and downright dangerous for viewing the Sun, and should NEVER be used for that purpose. Anything up to and including PERMANENT LOSS OF SIGHT could result.

We now return you to your regularly scheduled perusal of the BABB.

Pinemarten
2003-Aug-26, 01:38 AM
Thanx for the info.

I am probably going to do the wrong thing but....
I am shopping around for a good used light bucket before I even get binos. I had a 237x 60mm Tasco circa 1967 that I parted with years ago. I remember how limited it was outside the Sol system.
I figure if I buy used and I want to change, I can recoup my $$ or trade it in.
I live in a light polluted city, and hope to do some high-tech-microwave-trailer-generator-laptop-astro-camping this fall/winter.
I already know it is the best scope to buy because it will be the only one I use.
I don't know if this is the right forum, but any advice will be appreciated. My budget is around $800-1800CDN just for the scope. The camping stuff is cheap in winter here.

Charlie in Dayton
2003-Aug-28, 04:02 AM
Well well well, now we're gettin' right down to the real nitty gritty...

If you've got that much cash to blow, might I suggest you consider new as opposed to used? I found a recent deal from a manufacturer's web site sale -- 130mm Newt with equatorial mount, $207.95US shipped to my front door...

Be it new or used, consider ebay. Lots of scopes on there. And there's still those Celestron/Meade eyepiece kits available there. Half a dozen good eyepieces, a barlow, a handful of filters in an aluminum case...good deal!

Remember that the best scope is the biggest one you'll use on a regular basis. If it's too big to comfortably haul around, you will just have wasted money. And do you have room in the vehicle to comfortably stash it?

Check our esteemed host's website for advice on scope buying. And do a search on the forum...we've cussed and discussed this subject more than once.

Avail yourself of the knowledge of your fellow BABBlers...trust me on this, if there's a mistake to be made we've already made it, and we can help you from making it yourself.

Welcome to the league of time travelers... =D>

kingneptune8
2003-Aug-28, 11:00 PM
I was perusing Dobsonian type 'light buckets' on the net, and they have moon filters listed as an accessory. Are these to prevent eye damage, or do they have another purpose?
Not physical "damage" exactly. Using a light bucket to dump lunar light into your eye can be painful though--it's that bright. I sometimes use a moon filter even on my 90mm ETX.

Wow... didn't think of that, thank God I've used a filter :D

Pinemarten
2003-Sep-02, 05:01 PM
I do have a very large car ('75 Chev), but I will be moving across the city in the next month or two, so I will have to put my telescope on the back burner for a bit.
At least it will give me more time to shop around.

kingneptune8
2003-Sep-23, 09:44 PM
:o
U N BIQ VKUBS BI RGbja ri rgR QWKSUBF FKaa

Charlie in Dayton
2003-Sep-24, 01:45 AM
:o
U N BIQ VKUBS BI RGbja ri rgR QWKSUBF FKaa

I'll have whatever he's drinking...