Attaching a loose sheet of solar filter

So if the clouds leave us alone I have devised my method for viewing and photographing the eclipse.

I bought a 4x4" Thousand Oaks (ISO Certified) sheet of solar film on Amzn. Though I considered taping it to my Sigma 150-600mm C and shooting my 5dIII, I decided that magnification is king and that I'd be better off using my Nikon spotting scope and digiscoping the shot with my iPhone 7, shooting in DNG via Lightroom mobile. I have some Lunt Solar Systems (also ISO certified) viewing glasses arriving in the mail today.

I've already tapped the sunshade into place so that it wont jostle/wiggle around and inadvertently bump the filter off, but how would you mehcanically inclined folks secure the filter to to the end of the scope? I'm thinking of just cutting off the corners to complete the filter into a circle and just taping it around the edges of the sunshade. Wondering if there might be a more secure way that wouldn't leave the filter covered in tape residue and cut up. Suggestions?

Thanks!

Also want to confirm that the silvery, reflective side points towards the sun, not the matte, brown side. No instructions included

First thing I see is your laying it atop some kind of rough looking material and that's bad being face down . If you scratch it or cut it then it's useless . Silvery side out always . Make sure it covers the end of your lens completely so no sunlight whatsoever seeks through . What might be better than taping it is make a card board cap cover for the lens and tape the solar filter inside silverside outward . Then place it over your lens for a snug fit . Another member has made one that I talked about in one of the other threads here . See if you can find it and see what I'm talking about .

Thanks. Well I found this. I can see the benefit for a camera lens that has a filter holder, but not sure how it would benefit me for a spotting scope. But thanks for the warning about taping around the edges so no light gets through. I think I'll use black duct tape around the edges.

https://photography-on-the.net …read.php?t=1465​977&page=6

Celestron wrote in post #18429493
If you scratch it or cut it then it's useless ..

Point taken about it getting scrached, but not sure what you mean about cutting it. My point in trimming is to round it off into a circle so it can be taped all the way around the objective lens, not to cut across the diameter at all. Will it fall apart some how if I try to trim it?

If you trim it make it 1/4" - 1-2" bigger to make sure you have plenty overlap . Reason I mentioned your trimming is in your image looks like you had a small section not covering the total lens .

If you damage the film such that it develops so much as a pinhole, the filter is compromised and no longer safe to use.

Keep in mind you'll want the filter OFF for totality. Fashioning a cardboard holder that can quickly be dismounted is the way to go.

I built this filter cell with Seymour film in 2012. It's sized to slip snugly over the end of the Tamron 300/2.8 60B lens hood.

Here in arizona we're only supposed to get up to 70% occlusion, if that's the correct terminology. I'm guessing I'll still need the filter on ergo I wasn't planning on pulling it off (?)

If you're not going to be in the path of totality, then the filter stays on, yes.

You're still better off building a cell: It's less likely you'll damage the film, which should not be stretched or stressed, and it will be easier to store the filter safely until the eclipse.