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Coating Filters, Tests

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#1 colinbm

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Posted 30 June 2020 - 01:42

Following on from 'Sick S8612', 'AHA, Moment #1' & 'AHA, Moment #2.
I am going to test / evaluate a rain repellent on some filters, leading to evaluating the rain repellent on the troublesome BG type filters & others that suffer from atmosphere degradation.

The rain repellent I have randomly chosen is available at my local auto shop.
It is by Stoner, Invisible Glass, Rain Repellent. The product Safety Sheet lists these ingredients.
Dimethyl carbinol, CAS# 67-63-0, 40-60%
Ethyl alcohol, CAS# 64-17-5, 20-40%
2-propanone, CAS# 67-64-1 20-40%

This first test is to establish what effect it has on UV transmittance on glass.
For this I have chosen at random a 'UV cut / protector filter' of no know brand. I am at first surprised that this so called UV cut / protector filter, transmits UV quite well, in the sense of UV photography with a 'converted' domestic digital camera.

The first screen-shot is of the plain glass without any coatings & in full sunlight.
The second screen-shot is of the plain glass with the rain repellent applied.
PS. these shots were taken on two different days in full sunlight, their maybe some atmospheric differences ?
I hope some of you understand the scientific notations, because I am slowly learning them.

Attached Image: 20200630 UV Cut Filter in sunlight.jpg

Attached Image: 20200630 UV Cut Filter Coated with Invisible Glass in sunlight.jpg

#2 colinbm

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Posted 30 June 2020 - 04:23

I would consider the test with the clear glass was a success, as the UV end of the spectrum wasn't impacted much.

Now I will move on to testing the S8612. This is the oldest piece that I have & it has been cleaned multiple times & polished with fine cerium oxide.

First image is clear sky in sunshine at my location.
Second is the S8612 without any coatings but clean, in a clear sky & in sunshine.
Third is the S8612 with one coat of 'Invisible Glass' rain repellent, in a clear sky & in sunshine.

I will add some more coatings to the S8612 & post the result tomorrow.

Attached Image: 20200630 clear sky in sunlight.jpg

Attached Image: 20200630 S8612 uncoated clear sky in sunlight.jpg

Attached Image: 20200630 S8612 one coat clear sky in sunlight.jpg

#3 dabateman

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Posted 30 June 2020 - 06:07

Colin I am trying to figure out what you are adding exactly.
"Stoner, Invisible Glass, Rain Repellent. The product Safety Sheet lists these ingredients.
Dimethyl carbinol, CAS# 67-63-0, 40-60%
Ethyl alcohol, CAS# 64-17-5, 20-40%
2-propanone, CAS# 67-64-1 20-40%"

You have 40-60% isopropyl alcohol (IPA)
20-40% ethanol
20-40% acetone

So what is left? That list is all volatile and will evaporate.

Also take an image before and after. Is there any impact to contrast, apparent sharpness?

The UV range looks expanded but sensitivity seems reduced.

#4 colinbm

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Posted 30 June 2020 - 06:14

Dave the product is, "Stoner, Invisible Glass, Rain Repellent".
https://www.superche...3ml/354013.html

#5 dabateman

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Posted 30 June 2020 - 06:26

Your material safety data sheet was better than what I got in the USA. Mine just list:
Proprietary hydrocarbon blend


#6 colinbm

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Posted 30 June 2020 - 06:31

Thanks Dave
There would appear to be a secret ingredient that is not listed, I wonder why ?

#7 colinbm

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Posted 30 June 2020 - 06:38

I have given the S8612 a couple of coats & I will await the Suns return tomorrow & take another reading with the spectroscope.
After that I will leave the S8612 out on the cupboard top & see how it goes over time, like a couple of months. It is winter here & is normally dry in humidity & rain, so any reaction may be slow ?

#8 colinbm

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Posted 01 July 2020 - 07:11

The S8612 with triple coating with 'Stoner, Invisible Glass, Rain Repellent', taken in full sunlight.

I will report back over the next few months when there is some news on how the coatings are holding up to protecting the S8612 from atmospheric attack.

Attached Image: 20200701 S8612 triple coated in full Sunlight.jpg

Edited by colinbm, 01 July 2020 - 07:13.


#9 Andy Perrin

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Posted 01 July 2020 - 14:42

Colin do you have uncoated s8612 also to compare to? How will you judge the results?

#10 colinbm

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Posted 01 July 2020 - 19:54

Yes I do have another plain S8612.