fredmiranda.com
Login
This topic is in the 2011 archive. You can read it and like its posts here. It is read only.

Archive 2011What's this on my lens?

  
 
fotographiq
Offline

p.1 #1What's this on my lens?
What is this "glass hair" looking stuff on the inside of my lens? I purchased it this way, and it does not affect image quality, but I'm not sure what to make of it... any ideas?



Image taken with the lens (quality seems to be degraded by my image uploader host...):

Aug 24, 2011 at 12:48 PM
Vivek
Offline
Details
p.1 #2What's this on my lens?
Some fibers from cleaning perhaps; did you store it with your sweater ;-). The lenses are not sealed and you will see dust etc. get in there. You should be able to have it cleaned by Canon...
Aug 24, 2011 at 12:51 PM
fotographiq
Offline
Details
p.1 #3What's this on my lens?
@ sweater... no, no. I purchased it used, so perhaps the previous owner was a fan or Mr. Rogers, or Bill Cosby?
Aug 24, 2011 at 12:54 PM
wickerprints
Offline
Details
p.1 #4What's this on my lens?
Fungal hyphae.
Aug 24, 2011 at 12:59 PM
fotographiq
Offline
Details
p.1 #5What's this on my lens?
wickerprints wrote:
Fungal hyphae.


Are you positive, or hypothesizing?
Aug 24, 2011 at 01:01 PM
langdoy
Offline
Details
p.1 #6What's this on my lens?
What lens is that? I would return it to the seller if they didn't tell you prior to sale about it or get CPS gold and send it in for a cleaning.
Aug 24, 2011 at 01:17 PM
omarlyn
Offline
Details
p.1 #7What's this on my lens?
It's hard to say for sure but whenever you look at a lens element obliquely like that, you can get a reflection from the outside edge of the element(s) that appear to be on the surface of the glass. If there are any particles or fibers on the edges, that could be what you're seeing (as a reflection).

HTH,
Omar
Aug 24, 2011 at 01:18 PM
wickerprints
Offline
Details
p.1 #8What's this on my lens?
wickerprints wrote:
Fungal hyphae.

fotographiq wrote:
Are you positive, or hypothesizing?

How can I be certain when all I have in front of me is a blurry image? One needs to inspect it under high magnification to be certain; but I suspect it is fungus. "Fibers" don't just appear en masse in a lens like that.
Aug 24, 2011 at 01:34 PM
squareeyez
Offline
Details
p.1 #9What's this on my lens?
Hard to say without seeing it firsthand. Do you have a magnifying glass to get a better look at it? The first thing that comes to mind is fungus. I've seen it grow around fibrous matter like hairs before. Just a guess, though. If it doesn't affect IQ then... but it may just get worse over time. I also recall someone reporting mites in their lens before.
Aug 24, 2011 at 01:34 PM
runamuck
Offline
Details
p.1 #10What's this on my lens?
Put the lensin the sun for a while with the aperture wide open and pointing at the sun. Sunlight will kill the little buggers if it is fungus.
Aug 24, 2011 at 01:47 PM
canon pants
Offline
Details
p.1 #11What's this on my lens?
looks like fungus.
Aug 24, 2011 at 01:54 PM
fotographiq
Offline
Details
p.1 #12What's this on my lens?
Thanks guys. Lens is in sunlight now, just in case.

So... if it is indeed fungus, and it is not affecting image quality, AND I keep the lens in a dry, cool place... should I worry?
Aug 24, 2011 at 03:59 PM
RobertLynn
Offline
Details
p.1 #13What's this on my lens?
fotographiq wrote:
Thanks guys. Lens is in sunlight now, just in case.

So... if it is indeed fungus, and it is not affecting image quality, AND I keep the lens in a dry, cool place... should I worry?


Yes.

It'll probably get worse, waste the lens, and spread to you.

Okay, far fetched, but just my luck.

Contact the seller. Get a refund. Lens is junk in my eyes.
Aug 24, 2011 at 04:08 PM
fotographiq
Offline
Details
p.1 #14What's this on my lens?
The seller was KEH, and it was rated as UGLY. I think, even with the potential fungus, that it's a bargain. The photos I've taken with it don't lie. How much worse can it get, the fungus? I've done some reading and if kept in a cool place, and exposed to sun, it will be OK unless it's already too far gone (which is clearly is not in this case, would you say?)
Aug 24, 2011 at 04:42 PM
stebesplace
Offline
Details
p.1 #15What's this on my lens?
I wasn't aware KEH sold lenses with fungus on board...

However, I am now...

"Ugly" Very rough looking. Multiple impressions in metal, excessive finish loss and brassing. Glass will have marks, fungus and/or haze which will affect picture quality.

From the horses mouth: http://www.keh.com/PopupGrade.aspx
Aug 24, 2011 at 11:49 PM
fotographiq
Offline
Details
p.1 #16What's this on my lens?
Well, after a lot of reading it appears that there is no evidence that this can spread from lens to lens, so I will be keeping the lens. I live in a place of low humidity and not much heat, so chances are the fungus will not spread. I will take it to a local camera shop for confirmation of the Internet Diagnosis as well as to see if they will clean it.

For those curious, this is a first issue Sigma 70-200 2.8. As I have mentioned, the photos coming from it are absolutely stellar.
Aug 25, 2011 at 12:25 AM
Ben Horne
Offline
Details
p.1 #17What's this on my lens?
The lines seem rather angular, and reflecting specular light -- I wonder if the coating on the lens is "cracking." ...perhaps from past abuse such as extreme temperatures.

Fungus often has a nuclear center with arms that radiate outward. They are often more curvy than angular.

Aug 25, 2011 at 12:30 AM
squareeyez
Offline
Details
p.1 #18What's this on my lens?
Ben Horne wrote:
The lines seem rather angular, and reflecting specular light -- I wonder if the coating on the lens is "cracking." ...perhaps from past abuse such as extreme temperatures.

Fungus often has a nuclear center with arms that radiate outward. They are often more curvy than angular.



True - unless the fungus has taken opportunity of moisture and biologics relating from hairs. Have to admit, though, it would seem odd to have that much hair inside the lens. Sure would love to have a peek with a loupe
Aug 25, 2011 at 11:40 AM
kakomu
Offline
Details
p.1 #19What's this on my lens?
Ben Horne wrote:
The lines seem rather angular, and reflecting specular light -- I wonder if the coating on the lens is "cracking." ...perhaps from past abuse such as extreme temperatures.

Fungus often has a nuclear center with arms that radiate outward. They are often more curvy than angular.



To be honest, my first thought were cracks in the glass. Though, it depends on how large the glass is.

I don't think it's fungus because:
A) the pictures of fungus I've seen show the fibers far more tightly wound and very interconnected, like the blood vessels in an eye.
B) The actual strands that we see have light playing off of them (not sure if it's a reflection, refraction, etc) whereas the funguses I've seen are typically not particularly reflective or refractive.

I think the cracks you see are why it's rated "ugly" and may have been due to the lens taking a fall. I did drop a lens once and a tiny little crack formed near where the lens impacted that similar to the structure you see.
Aug 25, 2011 at 11:44 AM
FM ForumsCanon ForumJoin Upload & Sell
  
 

You are not logged inLog inRegister