Safe Solar Observing video

[BinocularSky]

Yeah, I know I could make a fortune selling recordings of my voice as a cure for insomnia but, as companion to my previous one:

[JamesM]

One quick question regarding the projection method. Does it make a difference what material has been used to construct the scopes baffles? The reason I ask this, is that I'm sure I read somewhere that the insides of some scopes melted due to plastic parts being used. Clearly the projected method is the safest but not if the scope is going to catch alight.

Many thanks for the video.

James

[BinocularSky]

Frankly, I don't know for certain (I've only ever used refractors with metal or MDF baffles) and, if you are uncertain, the sound advice is "DON'T".

If the projection is accurate, the focused Sun will not impinge upon the baffles, so they will not be melted by that. In my experience with the scopes I have used, there has been nothing to suggest that there has been any significant heating apart from the focuser/diagonal/eyepiece region, so I do not suspect that the internal temperature has risen sufficiently to melt baffles. The scope I did the filter fracture demonstration with has MDF baffles and there is no visual indication of thermal damage.

If anyone has a scope with plastic baffles that s/he would like to donate in the interests of science, I would gladly experiment and report here .

[Nova]

Thanks for the video. I watched the EP filter one also. Shocked that these types of filters are even available. I am eventually going to get some Baader solar film and give this a go myself. Do you have an tips/advice for checking the filter everytime before use? Im assuming you will be checking for pin holes, tears etc. Is it possible for the coating to come away leveing just see through plastic? Any advice appreciated

[BinocularSky]

Checking- I just check for scuffs, then hold the filter up to the Sun and look for pinholes. The nice thing about Baader AstroSolar Safety Film is that it is coated on both sides so, if the coating on one side has a pinhole (rare), you'll still have some protection from the coating on the other side.

The basic advice is firstly to understand the dangers, then to apply common sense and reasonable care and caution.