baader film

[bottletopburly]

Just thinking i  have a solar film cover i made for my scope, how long does the film last and how regular should it be replaced ? ,i haven`t used it in a long while but it must be a good 4 years old i would assume it has only a certain shelf life and after a certain time may start to break down .

[Uplooker]

As long as you protect it and store it safely it should last for years.

There may well be some degradation over time. Best to hold it up to the sun and inspect it for pin holes. If you do detect any holes, one or two, then just apply a small square of insulation tape to cover them. Even though you have "blanked out" small parts, it will have no effect on the views you get.

It would be good practice to always inspect the filter, by looking for pin holes, before each use.

[bottletopburly]

5 minutes ago, Uplooker said:

As long as you protect it and store it safely it should last for years.

There may well be some degradation over time. Best to hold it up to the sun and inspect it for pin holes. If you do detect any holes, one or two, then just apply a small square of insulation tape to cover them. Even though you have "blanked out" small parts, it will have no effect on the views you get.

It would be good practice to always inspect the filter, by looking for pin holes, before each use.

Cheers

 

[Bizibilder]

The filter I have has been in use since June 2011 - So six years and counting.  I can see no degradation in it and have not found any pinholes.  It is mounted in a homemade plastic holder and lives in a plastic box ("Celebrations" sweets container!) in the observatory, so it is out in all weathers and temperatures.

[Merlin66]

My Baader film is almost ten years old as still as good as new.....

Safety stored in dust proof container between uses.

 

[Peter Drew]

Apart from safety checks, avoid putting finger marks on the film, almost impossible to clean off without making things worse!   

[Louis D]

I made my Baader solar filter cells when the material first came out about 16 or 17 years ago.  I keep them in a container with stiff cardboard over the front to prevent damage to them.  Still pinhole free and working great all these years later, so I don't think the material degrades significantly over time.

[Luna-tic]

On ‎12‎/‎16‎/‎2017 at 05:37, Bizibilder said:

It....... lives in a plastic box ("Celebrations" sweets container!) in the observatory, so it is out in all weathers and temperatures.

 

On ‎12‎/‎16‎/‎2017 at 05:51, Merlin66 said:

Safety stored in dust proof container between uses.

 

On ‎12‎/‎16‎/‎2017 at 06:32, Louis D said:

 I keep them in a container with stiff cardboard over the front to prevent damage to them. 

Protect the film from abrasion, fingerprints and pinholes and it will last almost indefinitely, it's a polymer plastic. I have the Thousand Oaks film, very similar but gives the visible disc a nice orange color.

I made one for each of my SCT's and nest them with a piece of cardboard between them, inside a metal round cookie tin, like the ones you give at Christmas.

 

[Louis D]

58 minutes ago, Luna-tic said:

I have the Thousand Oaks film, very similar but gives the visible disc a nice orange color.

I bought their solar eclipse viewing glasses.  Everyone who compared them to the view through their own regular Mylar glasses thought they were vastly sharper.  I've thought about making some filters from the TO material for my newer scopes for comparison sake.

[Luna-tic]

This is from the August '17 total eclipse, shot through the Thousand Oaks film from a C6. The color, I think, is as much like the natural Sun, minus the extreme brightness. It allowed a really crisp focus, too.

[Merlin66]

The Baader solar film is not Mylar, but a very sophisticated polymer film.

I have and use the Baader film, and a  1000 Oaks glass filter (Type 2) and a Baader Herschel wedge.

I find the Baader film comes a close second to the Herschel wedge....

[Louis D]

On 1/12/2018 at 22:18, Merlin66 said:

The Baader solar film is not Mylar, but a very sophisticated polymer film.

I have and use the Baader film, and a  1000 Oaks glass filter (Type 2) and a Baader Herschel wedge.

I find the Baader film comes a close second to the Herschel wedge....

I had a TO glass filter years ago and passed it along to a friend after making my Baader filters.  Their polymer film is entirely new.  It's not coated, the filtering effect is throughout the entire film, so pinholes should be much less of an issue than with the glass filters of old.

How do you use a Herschel wedge with a Newtonian design?

[Stu]

On 13/01/2018 at 04:13, Luna-tic said:

The color, I think, is as much like the natural Sun, minus the extreme brightness.

Actually, the sun is white, not orange. It only appears orange or red when low down due to scattering of the shorter light frequencies by the atmosphere, otherwise it is white  

[Luna-tic]

4 hours ago, Stu said:

Actually, the sun is white, not orange. It only appears orange or red when low down due to scattering of the shorter light frequencies by the atmosphere, otherwise it is white  

You're right, I stand corrected. But since it looks yellow to us when looking up at it unfiltered (except for the atmosphere), I feel it's more 'natural' when looking through a filter that colors it that way. Besides, it is a yellow dwarf.

[Merlin66]

The Herschel wedge is for use on refractors....

[Louis D]

On 1/15/2018 at 15:19, Merlin66 said:

The Herschel wedge is for use on refractors....

So us Newtonian users don't really have an alternative option to using full aperture solar filters.

Would Herschel wedges damage field flattener optics near the focal plane by allowing unfiltered solar energy through them?

[Merlin66]

If you mean Petzval design refractor with correction elements at the rear, then no.

TV, WO, and Takahashi have all confirmed that their Petzval designs are 100% safe to use with a Herschel Wedge.

If you mean with an added flattener element added at the eyepiece/ camera......these are not required for solar, so not an issue.