Solar Observing - Melted Eyepiece / Diagonal

[Robny]

Hello Group

I recently purchased an ST80 primarily as a guide scope but also as a grab and go, the scope came with a ready made solar filter so i decided to do a bit of solar observation today. I was using the stock 10mm eyepiece and diagonal that normally comes with the skywatcher gear, packing away my bits and bobs i smelt a horrible chemical like smell. I checked the eyepiece and was shocked to see this:

And my diagonal was like this, also smelling (see the dark area is wear it burned)

After seeing this, i checked over the scope and it was fine, i also checked the solar filter and there was no signs of deterioration what so over. So my only conclusion is that i should not be solar observing with stock eyepiece and diagonals??? would this be a correct assumption or is there something else thats gone wrong here. I'd like to get your opinions before going out looking at the sun again.

Many Thanks

Rob

[Bizibilder]

Something is definately wrong! I assume the solar filter was a full aparture filter that fits over the objective of the scope? Or was it something else?

[Robny]

Something is definately wrong! I assume the solar filter was a full aparture filter that fits over the objective of the scope? Or was it something else?

It was a full aperture solar filter, it seems to be a ready made one that was purchased (I bought the scope used, the filter came with) from a retailer going from the stickers on the brown box the filter was in.

[DirkSteele]

Something has gone terribly wrong. I have seen similar damage caused by someone using eyepiece projection of the sun onto a screen years ago, but there is no way anything like the amount of energy required to do that should be passed by a solar filter. Just to confirm, you used a solar filter that fully covers the primary objective of the scope?

[DirkSteele]

I would suggest a very careful inspection to make sure there is no damage to the filter. Look for small tears if it is a film type material, and scratches if it is a glass filter.

[Naemeth]

I sincerely hope the solar filter was the film aperture over the front objective and not an eyepiece filter. If it is an eyepiece filter, bin it!

Always check solar film before using it by holding it up to the Sun, if you can see any pinholes you should not use it under any circumstance.

[Robny]

Something has gone terribly wrong. I have seen similar damage caused by someone using eyepiece projection of the sun onto a screen years ago, but there is no way anything like the amount of energy required to do that should be passed by a solar filter. Just to confirm, you used a solar filter that fully covers the primary objective of the scope?

Thats correct full aperture - and I was only observing for about 15 mins!!!

[DaveGarland]

Just be thankful you weren't looking through the eyepiece!!!

[Robny]

I sincerely hope the solar filter was the film aperture over the front objective and not an eyepiece filter. If it is an eyepiece filter, bin it!

Always check solar film before using it by holding it up to the Sun, if you can see any pinholes you should not use it under any circumstance.

I was so paranoid before using it, I did check it against the sun and no pin holes were found and after seeing the damage i also checked it against the sun again to check for pin holes and nothing was found. It is a full 80mm diameter filter that fits the entire scope aperture

[Robny]

Just be thankful you weren't looking through the eyepiece!!!

Thats what i don't understand we (my wife and i) were looking through the eyepiece constantly taking in turns, I guess i can thank my lucky starts it seems to have been focused on the edge and not in the centre.

I was shocked and thankful when i saw that, most definitely...erm, an eyeopener.

[Robny]

I take it the eyepiece is not to blame for this then?

So I can only presume that it must be the filter although i see no damage on it?

[Naemeth]

I was so paranoid before using it, I did check it against the sun and no pin holes were found and after seeing the damage i also checked it against the sun again to check for pin holes and nothing was found. It is a full 80mm diameter filter that fits the entire scope aperture

That's really odd. Did you try the torch method too?

[John]

Was there any period of time, even for a few seconds, where the scope was could have been pointing at the sun without the filter in place ?.

If the aperture of the scope was fully covered by the filter at all times I can't see how that damage could have occured to be honest.

[Robny]

That's really odd. Did you try the torch method too?

Im unfamiliar with the torch method?

[The Sailor]

I would like to see a photograph of the filter if possible, not disbeliving Rob but would like to know and see what has happened. Could the filter moved in any way, wind catching it, holding it up enough to allow the sun in.

Jim

[Robny]

Was there any period of time, even for a few seconds, where the scope was could have been pointing at the sun without the filter in place ?.

If the aperture of the scope was fully covered by the filter at all times I can't see how that damage could have occured to be honest.

Errrm - Well, I Set up the scope originally guessing the correct alignment, then i placed the solar filter on the front and to my surprise it was almost perfect when i looked through, so i guess the answer to your question is quite possibly

[John]

Errrm - Well, I Set up the scope originally guessing the correct alignment, then i placed the solar filter on the front and to my surprise it was almost perfect when i looked through, so i guess the answer to your question is quite possibly

The rule is filter on first, before you line up the scope, before you put in an eyepiece !

Well now you know why

[earth titan]

Errrm - Well, I Set up the scope originally guessing the correct alignment, then i placed the solar filter on the front and to my surprise it was almost perfect when i looked through, so i guess the answer to your question is quite possibly

That sounds like the problem to me.

Always put the filter on well away from the sun and make sure any finders, telrads, etc are also covered and the covers taped on. Don't want a gust blowing them off!

Typed by me on my fone, using fumms... Excuse eny speling errurs.

[Robny]

I would like to see a photograph of the filter if possible, not disbeliving Rob but would like to know and see what has happened. Could the filter moved in any way, wind catching it, holding it up enough to allow the sun in.

Jim

Please see below:

[Robny]

The rule is filter on first, before you line up the scope, before you put in an eyepiece !

Well now you know why

Got it!

Many Thanks, we live and learn - my inexperience showing through

[Naemeth]

Im unfamiliar with the torch method?

Probably one I made up to be honest, shine a bright torch through it, if you can see any light through it's clearly got a hole in! You can try hold it up to a house light and you shouldn't see light.

Always put the filter on first, and remove all finders .

[Paul M]

Got it!

Many Thanks, we live and learn - my inexperience showing through

Never mind, it was a relatively cheap lesson.

I had a solar lesson at 11 years old that cost me the centre of vision in my right eye.

I wasn't even looking through the scope

[The Sailor]

Thanks for the photo of the filter Rob, I think we have come to the conclusion that you slew to the sun and then fitted the filter, no sence going on at you, a lesson learnt

Jim

[Robny]

Never mind, it was a relatively cheap lesson. I had a solar lesson at 11 years old that cost me the centre of vision in my right eye. I wasn't even looking through the scope

Oh wow, sorry to hear - no more complaining over a free eyepiece from me then

Thanks for the photo of the filter Rob, I think we have come to the conclusion that you slew to the sun and then fitted the filter, no sence going on at you, a lesson learnt Jim

No worries - I'm just happy i was using the freebie eyepieces and not my 'main ones'

[E621Keith]

Errrm - Well, I Set up the scope originally guessing the correct alignment, then i placed the solar filter on the front and to my surprise it was almost perfect when i looked through, so i guess the answer to your question is quite possibly

I'm glad your eyes are OK. As others pointed out and as you already know, the scope must be filtered at all times. You should 'guess' correct alignment by using the shadow method, not the one you used.

If you don't have a sun finder, the best way to find the sun is to observe shadow on the ground. The scope will cast the smallest shadow when it is pointed directly at the sun.