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Finally discovered what the prism fungus/crystal entity is
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PostPosted: Thu Mar 16, 2017 7:53 pm    Post subject: Finally discovered what the prism fungus/crystal entity is Reply with quote
You know that frequent prism degradation looking like crystal growing or fungus or alien form? Can be different colors...
I have many DDR Praktica cameras with such problem. Finally resolved; I hope you can check any of these links:

https://www.facebook.com/kowalskipottery
https://www.facebook.com/boredpanda/videos/10154280054029252/?pnref=story


PostPosted: Fri Mar 17, 2017 12:36 am    Post subject: Reply with quote
Tinned meat?


PostPosted: Thu May 25, 2017 8:45 am    Post subject: Reply with quote
This time in lens element or rare type of separation: Click here to see on Ebay.de


PostPosted: Fri May 26, 2017 12:35 am    Post subject: Reply with quote
Looks fungal to me!


PostPosted: Fri May 26, 2017 9:34 am    Post subject: Reply with quote
Two pottery links and an out of date ebay page?


PostPosted: Fri May 26, 2017 12:37 pm    Post subject: Reply with quote
Fungal acid reaction or oxidation of lens coating?


PostPosted: Fri May 26, 2017 2:02 pm    Post subject: Reply with quote
Its not fungal, and pottery links show the reaction necessary to make such formations.


PostPosted: Fri May 26, 2017 2:26 pm    Post subject: Reply with quote
Pancolart wrote:
Its not fungal, and pottery links show the reaction necessary to make such formations.


Yes, but what is the origin of the acid - or are you implying that it's a manufacturing defect, or some violent cleaning attempt?


PostPosted: Fri May 26, 2017 10:43 pm    Post subject: Reply with quote
See prisms for instance. The formation starts inside without any contact to air thus spores are excluded. My guess is material degradation (structural change) influenced by temperature and possibly light.


PostPosted: Sat May 27, 2017 9:16 am    Post subject: Reply with quote
Pancolart wrote:
See prisms for instance. The formation starts inside without any contact to air thus spores are excluded. My guess is material degradation (structural change) influenced by temperature and possibly light.


It would be interesting to hear from a chemist on the possible cause. Does it affect image quality on the image or it visible in the viewfinder in the case of the prism? I've never even known of this before. I believe Pentaprisms only use a coating of aluminium oxide, and silver for the mirroring? Lens coatings and even their elemental composition is much more complex, and of course doublets include organic cements.


PostPosted: Sat May 27, 2017 2:50 pm    Post subject: Reply with quote
Hrm . . . I wonder if this is what's happened to my F2's DE-1 prism finder. I noticed a few years ago that there was a blurry dark spot toward the top of the viewing area when looking through the finder. I assumed impact damage, since my finder had picked up a very slight bump on the top. Well, just the other day, I dismantled my DE-1 and I was surprised to find that the outer surface of that coating on the prism was without any visible damage at all. Yet, when peering into the prism, I can see this tiny gray spot. So, now I'm wondering if my DE-1 may have this problem. Does this seem plausible?


PostPosted: Wed May 31, 2017 10:43 am    Post subject: Reply with quote
cooltouch wrote:
Hrm . . . I wonder if this is what's happened to my F2's DE-1 prism finder. I noticed a few years ago that there was a blurry dark spot toward the top of the viewing area when looking through the finder. I assumed impact damage, since my finder had picked up a very slight bump on the top. Well, just the other day, I dismantled my DE-1 and I was surprised to find that the outer surface of that coating on the prism was without any visible damage at all. Yet, when peering into the prism, I can see this tiny gray spot. So, now I'm wondering if my DE-1 may have this problem. Does this seem plausible?

It certainly does. I've seen so many. And some really look so alive i've made daring speculation: this is the missing link to origins of life Smile.
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