Recommendations for Sunfilters for Celestron Nexstar 4se

[Jbagwell97]

Hi,

Amateur astronomer here.

I am wanting to do some sun viewing and I was wondering what is the best Solar filter for a Nexstar 4se telescope.

Also any advice on what type of eyepiece to use, and so on.

I apreciate the advice

 

[Mandy D]

1 minute ago, Jbagwell97 said:

Hi,

Amateur astronomer here.

I am wanting to do some sun viewing and I was wondering what is the best Solar filter for a Nexstar 4se telescope.

Also any advice on what type of eyepiece to use, and so on.

I apreciate the advice

 

Baader solar film. Make your own frame for it to go over the full aperture of your scope. Don't forget to cover your finderscope or filter that too. Make sure you get the visual density of film and follow the instructions.

[Jbagwell97]

5 minutes ago, Mandy D said:

Baader solar film. Make your own frame for it to go over the full aperture of your scope. Don't forget to cover your finderscope or filter that too. Make sure you get the visual density of film and follow the instructions.

Cheers. I will look into this.

I see some on amazon which says neutral density, when you say "get the visual density of the film" what exactly do you mean?

- Joe

 

[Mandy D]

7 minutes ago, Jbagwell97 said:

Cheers. I will look into this.

I see some on amazon which says neutral density, when you say "get the visual density of the film" what exactly do you mean?

- Joe

 

This stuff:

https://www.rothervalleyoptics.co.uk/baader-astrosolar-nd50-safety-film-sheet.html

Do NOT use regular ND filters that you see for cameras. You need to attenuate the sunlight by a factor of 100, 000 times for visual observation. Camera filters will NOT do this. Amazon is not really the place to go when looking for things that you depend on for your safety!!! Follow the instructions carefully. There is also photographic density, which is not safe for direct viewing with your eyes. It only attenuates by a factor of 10,000.

Edited September 2, 2023 by Mandy D
Additional info

[Elp]

Only get the film sold by actual astronomy retailers. Baader film comes in a visual one, and photographic one. I bought the highest nd one for safety (for visual) and can also image with it. Seymour Solar also do one, the sun is a yellow orange colour through it, the baader one shows the sun as white/grey.

Edited September 2, 2023 by Elp

[Jbagwell97]

15 minutes ago, Mandy D said:

This stuff:

https://www.rothervalleyoptics.co.uk/baader-astrosolar-nd50-safety-film-sheet.html

Do NOT use regular ND filters that you see for cameras. You need to attenuate the sunlight by a factor of 100, 000 times for visual observation. Camera filters will NOT do this. Amazon is not really the place to go when looking for things that you depend on for your safety!!! Follow the instructions carefully. There is also photographic density, which is not safe for direct viewing with your eyes. It only attenuates by a factor of 10,000.

 

14 minutes ago, Elp said:

Only get the film sold by actual astronomy retailers. Baader film comes in a visual one, and photographic one. I bought the highest nd one for safety (for visual) and can also image with it. Seymour Solar also do one, the sun is a yellow orange colour through it, the baader one shows the sun as white/grey.

Cheers,

 

I will look into both of these. 

 

Yes, last thing i want to do is blind myself with somthing cheap or not suited for purpose.

 

Thank you both for your advice

[Louis D]

Thousands Oaks also sells a few varieties of solar film that render the sun yellow-orange.

3 hours ago, Jbagwell97 said:

Yes, last thing i want to do is blind myself with somthing cheap or not suited for purpose.

Another problem noted with the Chinese made solar filters is that they mount the film in a stressed manner leading to loss of resolution.  Wrinkles don't matter, but stretching tightly does.  It looks nice and flat, but that's actually detrimental for films.

Another unknown with the Chinese made solar filters is how well they filter out of visual band light (UV and IR).  I haven't seen any independent spectrographs of any of them, but have seen plenty of them for Baader, Thousand Oaks, and Solar Skreen (example below).