Major error while watching the sun

[N3ptune]

I was told the sun was really dangerous, today I had a scary demonstration of if.

--> I think I have to be glad for that incident.

All this was done in less then 1 minute: After my observation of the sun  I left the scope pointed to the it then I removed my eyepiece AND badder Astrosolar sheet.  Then I put my plastic cap protector on my focuser. 

In a matter of less then 30 seconds, the sun punched a hole into the plastic cap producing a thick melted plastic smog INSIDE the tube.

At first I was like: OH BOTHER! this dust is going to get on the optic then 5 seconds after I thought I could have look at the secondary with my naked eye, and OBVIOUSLY, get serious damage myself.  If the sun can punch a hole in 2mm solid plastic...

)):

The sun gave me a serious lesson today ):

I am unharmed fortunately.

 

[cloudsweeper]

I learned a lesson from the Sun too.  I had the Baader filter in place, with only the small aperture in use; the finderscope was covered.  The Baader had been tested for pinholes against a strong source of light.

I lined the Sun up with the shadow method, then took a look at the sunspots.  I must have spent well over an hour doing this, then found my vision was slightly blurred for the following few hours.  

If I ever try this again, I shall:

# not do it for long,

# not do it when the Sun is high,

# not do it at very low magnification,

# reduce the aperture even further,

# maybe even use a Moon filter as well.

I feel anything less could pose a serious risk to my vision!  

Doug.

[Ant]

Pleased that you are both ok.

 

Even observing using the baader solar film in place the sun can still be quite bright. So I tend to use a variable polarising filter at the EP end just to lower the brightness a little further, and make it more comfortable.

 

Obviously the polarising filter IS NOT a replacement for the solar film - it should be used in addition to the solar film.

Ant

[Moonshane]

This is why I feel a herschel wedge is the only truly safe way to observe in white light.

[Piero]

Scary tale this one! Glad both of you are safe.

The Sun is a wonderful target, but requires extra care. Think about if a child or a neighbour or whoever else was nearby the telescope and didn't know the danger of watching the Sun without a proper solar filter. Never leave the telescope alone when watching the Sun and be absolutely sure that all the required steps (e.g. application of a solar filter, or solar film or composition of filters for the wedge) are executed correctly. 

 

[N3ptune]

didn't had blurry vision yet.  But after a few minutes of watching the sun with 1 eye, the colour of the deck is not the same for both eyes. On the other hand, that may be normal because 1 eye is closed and the other is exposed.

I didn't felt the need to use my variable polarizing filter with the sun strange, I can't watch the moon without it. But maybe it would be a good thing to use it anyway next time...

Those are the picture of the pierced plastic cover... the hole is far from the centre of the cap too which I think is bad news toward my understanding of collimation.

[101nut]

10 minutes ago, cloudsweeper said:

I learned a lesson from the Sun too.  I had the Baader filter in place, with only the small aperture in use; the finderscope was covered.  The Baader had been tested for pinholes against a strong source of light.

I lined the Sun up with the shadow method, then took a look at the sunspots.  I must have spent well over an hour doing this, then found my vision was slightly blurred for the following few hours.  

If I ever try this again, I shall:

# not do it for long,

# not do it when the Sun is high,

# not do it at very low magnification,

# reduce the aperture even further,

# maybe even even use a Moon filter as well.

I feel anything less could pose a serious risk to my vision!  

Doug.

As has been said, the sun is still quite bright even through film. Taking the issues in turn:

Looking for too long is like staring into a torch and will make one eye tired, can sometimes give a short-lived after-image (a bright spot) on the retina, and thus make vision 'unbalanced' for a while - take a break now and again.

Sun low or high makes little difference to the brightness but the lower it is, the worse the image will be.

Low magnification may cause one eye to tire (as above) and generate a brighter spot on the retina.

Reducing the aperture will reduce the brightness and resolution. A variable polarizing filter is a better suggestion to tune brightness how you like it.

A solar continuum filter may work with film (though I haven't tried) to increase contrast. Not sure what a moon filter would look like but may be worth a try if it's a neutral density type. Be aware that introducing extra glass surfaces risks reflections and may actually decrease contrast and increase eye strain ... experimentation is the key.

If the film is Baader 5.0 visual, you've tested the filter (as you describe) and mounted it properly then there should be absolutely no risk to your eyesight.

 

[pipnina]

I'd already decided that if I ever get into solar, it would be in a pre-assembled scope for Ha or CaK but this makes me only more wary of white light viewing.

Glad to hear you're ok.

    ~pip

[Moonshane]

As long as the right equipment is used correctly there is no danger from any kind of solar observing.  The key words of course being right equipment and correctly.

[jetstream]

1 hour ago, Moonshane said:

This is why I feel a herschel wedge is the only truly safe way to observe in white light.

This is a great point Shane, I feel the same way. No worries about pinholes, punctures etc and the price of them is not cost prohibitive, Lunt makes a nice wedge.

[N3ptune]

i think it's not possible to use a wedge on a newton telescope.

[Moonshane]

That's true but I'd still say it's the safest way to observe in white light. The purchase of an additional (possibly cheap) achromat is a small price to pay for such safety offered by the Herschel wedge.

[Moonshane]

you were lucky not to shatter your secondary too. I doubt there's an issue with collimation as the sun would have moved off axis assuming it's not a driven scope.

I am truly thankful you didn't inadvertently glimpse through the eyepiece.

[jnb]

I don't often do solar observation with my scope but when I do it's through a filter and with a webcam in place of the eyepiece. If it's a dedicated solar scope that I would happily use naked eye but as I can afford a few pounds for a home made filter but not a few thousand for a bigger coronado I'll use the webcam.

 

[N3ptune]

Moonshane,  I will have to be more careful really but it's impossible to get another telescope for the sun right now.

The secondary mirror looks ok I don't see anything unusual on it, the total exposition time was about 60 seconds. I went out tonight to test the telescope and watched the moon at an astonishing 425x,  the Grimaldi crater. The view was sharp crystal clear really. It was the first time ever I had a clean image at 400x.

I guess the telescope is ok after all.

 

[paulastro]

It's most important that you always pay attention to what you are doing and don't allow yourself to be distracted - and this never changes however long you have been observing the Sun.  In some ways it's easier to make a mistake the more experience you have  as complacency can easily set in.  It's safest if  the first thing you do after observing the Sun is immediately to turn the scope way in another direction.  I have done exactly the same as you did myself - as well as other daft things over the years.  Experience will not protect you,   ALWAYS be aware of what you are doing and think safety at all times.

 

[N3ptune]

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It's most important that you always pay attention to what you are doing and don't allow yourself to be distracted -

Quote

ALWAYS be aware of what you are doing and think safety at all times.

Ahh I agree.. the same apply for when I take my car for a drive, <-- Always be aware of what I do and never forget just that.

Thanks.

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Actually I also did not tested the Baader Astrosolar for pinholes before use.. Another essential safety trick... I am glad we had that discussion.