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thegrump
26-10-2015, 2:25pm
I was just informed by AM that I had dust bunnies. On cleaning and close inspection of my lens, I noticed one of the internal lenses looked like it had grazing on it. There is also a small segment on the inside of the outer lens. What does this mean.

I @ M
26-10-2015, 2:46pm
The "dust bunnies" that Am was referring to are small particles of dust or lubricant on the filter that covers the sensor in the camera .​ Any dust or marks that you see in a lens may or may not impact on image quality depending on the severity of said dust or marks. Generally marks or dust towards the front elements of a lens will never be seen in an image and it takes a fair amount of dust, fungus or scratches on the more rearward lens elements before you have issues with image quality. If you are worried about those deposits or marks in the lens, have it examined by a service company and likewise, removing dust from the sensor filter can be done by a service company or by your self when you have learned the relatively simple process involved to clean a sensor.

ameerat42
26-10-2015, 3:01pm
TG. Can you point me to this post? Definitely get your lenses looked at (cheaply, of course, like at a local photo store).
If you can, post some pictures of the offending marks on your lens. It would involve a bit of close-up work, but you could try.
Am.

thegrump
26-10-2015, 4:24pm
any clue on the lens. Here is a shot of white paper OOF f11. to see if anyone can spot anything.

121034

ameerat42
26-10-2015, 5:44pm
Nope! That's for checking your sensor. That has a few blemishes that you can see with an
"Auto Levels" adjustment, but for just about everything they shouldn't matter.

For your lens you need to photograph the surfaces. Open the aperture to maximum and put a macro
(you've started macro haven't you?) lens on and focus on the different surfaces that have the blemishes.

thegrump
26-10-2015, 8:30pm
am...Not sure if this is what you meant, but, set the camera to macro, f4.


121044

ameerat42
26-10-2015, 9:04pm
Basically, just take a photo of the surfaces of your crook lens using macro gear. Just like any close-up object.
The trick is to get the blemish to show up. You might need to have a brightish background. OK, do you have a webcam,
camera phone...? Do something like below.

Back of lens (roughly with smartphone camera).
121045

thegrump
26-10-2015, 9:25pm
Ok.. I might have to wait until daylight. Thanks

thegrump
27-10-2015, 11:04am
It looks worse than it is, with the light, and being out of focus, but still is it an optic or something more sinister.

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ameerat42
27-10-2015, 11:52am
Yep. Eventually you'll get light scattering through that as it gets worse. Does it respond to any cleaning?

I would still use it though. And which lens is it, the one you recently bought?

thegrump
27-10-2015, 12:40pm
It is the lens I just bought, 70-300. It was second hand and pretty cheap. Now I know why. I will try to get my money back. HA HA. What is it ?. Can I disassemble the lens and try and clean it ?

davidd
27-10-2015, 1:50pm
It looks like a fungus. Keep that lens away from your other ones, it can spread. :eek:

mpb
27-10-2015, 2:00pm
I would still use it though. And which lens is it, the one you recently bought?

I personally would not use it. You run the risk of the spores getting into your camera and transferred to another lens, especially if its a zoom lens.
If it looks worse than those photos, I would say its a pretty back case of fungus.

I don't suppose there is a good case of fungus on a lens, only on the BBQ with a nice piece of fillet steak.

ameerat42
27-10-2015, 2:10pm
Mark, David. This is the coating surface that's crazing, not spores from a fungus.

TG. To be sure, take it to someone reputable - got a local photographer handy? - to give it an "eyeball".

Or, take it with you to one of the meets and let some others have a good look at it.

arthurking83
27-10-2015, 2:32pm
Mark, David. This is the coating surface that's crazing, not spores from a fungus.

TG. To be sure, take it to someone reputable - got a local photographer handy? - to give it an "eyeball".

Or, take it with you to one of the meets and let some others have a good look at it.
I think that's definitely fungus. Lens isn't worth cleaning, as it's value is less than the cleaning cost.
Like David said important to keep it away from your other lenses.

Sent from my HUAWEI MT7-L09 using Tapatalk

arthurking83
27-10-2015, 2:35pm
But, this has nothing to do with the dust bunnies that Am referred too in the other post.
It's high on impossible to get anything remotely captured in an exposure from within the lens.
Maybe if you had enough extension tubes... But other than that, remote!

Sent from my HUAWEI MT7-L09 using Tapatalk

thegrump
27-10-2015, 3:29pm
I could take it to TEDS they are local and handy.:lol::lol::lol::lol:

Cage
27-10-2015, 4:27pm
That is very definitely fungus !

I bought some used lens years ago from Queensland, the home of lens fungus.

A couple were quite good lens so I tried the UV treatment. You pick a nice sunny day with a high Slip, Slop, Slap reading, and put the lens in the sun so that direct sunlight gets onto the glass for an hour or so. It wont remove the fungus but it sure kills it and stops it getting any bigger. This wont kill spores hiding in the lens barrel away from the lens glass.

It is almost impossible to remove as some fungus actually eats into the lens coating.

Definitely isolate the lens from your other gear, and if you do use it, be aware, as Mark said above, that the spores could get into your camera and spread to your other lens.

Personally, I'd recycle it, and write the loss off as part of the learning curve.

Be very, very wary of buying any camera lens from Qld, NT and the northern half of WA.

ameerat42
27-10-2015, 6:52pm
TG. I could well be wrong. Be cautious with it. Get it checked.
Am.

arthurking83
27-10-2015, 6:59pm
....

Personally, I'd recycle it, and write the loss off as part of the learning curve ......

This is the best post in this thread so far .. but with a bit of explanation as to why.

One thing I've learned over the years, is that it never hurts to know more about something that to know less about that something.

Take lenses for example, I'm assuming that TG doesnt' know much about the inner workings of a lens(as most folks don't), nor how to pull one apart(but not so much to "tiny bits" :D) .. and this situations now presents itself as a great opportunity to learn.
The lens is basically junk now .. as already said(and it can't be stressed too highly here) .. do your best to keep it away from the other gear whilst stored.
During the day tho, there isn't all that much of a chance for the fungi spores to really move about too much(but it's possible). So you could still use the lens on the odd occasion, but try to keep it on the camera for a short a time as you can(ie. don't pack the camera away with this lens attached!!!!)

So the learning process Cage mentioned could be .. pull it apart, try to clean it yerself try to get it back together again and see what happens.
Personally I wouldn't sell it(a personal philosophy) .. so it's really a paperweight now .. but a teaching aide type of paperweight, I guess!

Note that IF(big IFF here) you do try to disassemble the lens, that the screws on the rear mount are NOT philips head screws no matter how identical they look.
The actual head type is called JIS(Japanese Indsutrial Standard or soemthing) .. is a particular Japanese design.
Philips screws appear to slot in nicely, but this is only an illusion. There's a 101% likelyhood that if you use a well fitting philips driver it will slightly damage the head on the screw.
Those drivers can be had on ebay and suchlike .. but pretty much impossible to get at any local shops here in Aus(that I've tried) .. and I've tried some fairly specialised screw/tool shops they hadn't even heard of JIS! :rolleyes:

Anyhow .. if this were mine(ie. I was in your situation!) .. the lens has finally revealed it's usefulness and the fun has just only begun! :th3:

ameerat42
27-10-2015, 7:16pm
OK. Now I am just doubtful.
Here is a page of "published" lens fungus images:
https://www.google.com.au/search?q=lens+fungus&tbm=isch&tbo=u&source=univ&sa=X&ved=0CBwQsARqFQoTCMjAkruZ4sgCFYKppgodbIEPUg&biw=1920&bih=916

and here is a page of "published" lens crazing images:
https://www.google.com.au/search?q=lens+crazing&tbm=isch&tbo=u&source=univ&sa=X&ved=0CCQQsARqFQoTCPWOq8GZ4sgCFQSfpgodHR8BrA&biw=1920&bih=916

"published" because we cannot be certain of Internet content.

TG. Have a good look at it all and TELL US what you think you've got there. - It could be both.
I just can't tell from your single image.

thegrump
27-10-2015, 8:00pm
arthur...Exactly what I was thinking. It is junk so i might as well have a play with it. I have a set of about 100 different driver heads, so most likely I will find one to fit. Will leave it for awhile, so I can get it checked by some one who knows. I heard about fungus a little while back, and thought that, that is what it might be. Thanks all.

Cage
27-10-2015, 8:18pm
@ AM

If you have a close look at those links you posted the 'crazing' shots have more symmetry to them, whereas the 'fungus' shots look more like somewhat random spider webs.

I can speak with some authority here as I have some personal experience with the dreaded lens fungus.

ameerat42
27-10-2015, 8:22pm
Yep. I agree, Kev. I just can't make much out from the image TG posted - not a criticism, but I just can't decide on it.
Just my 2c, but I will not insist on it.

Cage
27-10-2015, 8:25pm
arthur...Exactly what I was thinking. It is junk so i might as well have a play with it. I have a set of about 100 different driver heads, so most likely I will find one to fit. Will leave it for awhile, so I can get it checked by some one who knows. I heard about fungus a little while back, and thought that, that is what it might be. Thanks all.

Grump, other than finding out about how lens disassemble, and don't go back together as expected, this will almost certainly prove to be a fruitless exercise.

Bin it Mate, and move on.

And when you are looking at a replacement, don't be afraid to throw the link up here, as there are plenty of folk who will give you their two bobs worth, based on personal experience.

arthurking83
27-10-2015, 8:44pm
An old thread about lens fungus here: (http://www.ausphotography.net.au/forum/showthread.php?137221-need-assistance&highlight=lens+fungus)

These are the images I posted of the lens in that thread that had fungus in it.
First one is of the fungus in the lens:
http://www.ausphotography.net.au/forum/attachment.php?attachmentid=114397

Took me about 5-10mins to take the rear mount and the rear most lens off and clean the fungus off the affected lens:
http://www.ausphotography.net.au/forum/attachment.php?attachmentid=114396

Note tho that this was a much more simple(design) M42 lens, and a bit less complicated than a typical modern Nikon lens.
I actually took the lens apart to modify it to focus to infinity, more so that the check for fungus .. but the two jobs went hand in hand.
While there was a small amount of residual fungus in the lens as you can see some spotting in the second image, all it'd have taken is another 5 or so mins of cleaning to remove close to 99.9% of it.
All I used to clean it was a cotton bud, and some Eclipse fluid(which is just pure alcohol of some type) which is normally used for cleaning dust off a sensor.

I think I still have the lens, but it's in some unknown location(I may have chucked it too tho, can't remember).
But for the sake of surety, I just got another cheapie $20 lens off ebay to replace it.

.. just checked the most likely place I'd have stored it .. and it's not there .. so I reckon I chucked it.

taztek
27-10-2015, 9:16pm
Take that lens and seal it in a clip lock bag immediately.
DO NOT put it any where near the rest of your gear.
I lost a whole kit due to fungus.
Even L series lenses copped it.
Canon said it wasn't worth 'repairing' as the fungus 'eats into the coatings on the elements'.
I like the idea of putting it out in the midday sun to kill off the living fungus. (but there's still the spores that spread everywhere)
And I like the idea of pulling it apart, BUT not inside the house.
While its in the house its in the clip lock!!

thegrump
27-10-2015, 10:48pm
I hope I'm not too late. I swap the lenses from case to case depending on which I am using at the time. So there could be a lot of cross contamination.

arthurking83
28-10-2015, 6:32am
The advice I received when I found my lens with fungus is not to panic as much as some internet sources make out you should.
The spores don't propagate as quickly as some would have you think they do .. especially in colder climates(like Greensborough can be! ;))

But like I said before, it's 'storing them' that the issue.
When we refer to storage, we usually refer to the storage in some darkened location(bag, box, cupboard, drawer etc).
It's (apparently) in this dark(and more moist conditions) that fungus like to propagate ... which make sense when you think about it .. mushrooms, mould and the comment Cage mentioned re the sunlight/UV treatment trick.

While we do get the occasional dark and moist(humid) days down here .. they're too far apart for it to be a proper issue(although this weekend is apparently going to be a bit tropo!)


I hope I'm not too late. I swap the lenses from case to case depending on which I am using at the time. So there could be a lot of cross contamination.

And I'm pretty confident in my belief that you'll be fine.
If I start to spot any fungus on any of my other lenses that were stored with my fungus affected lens, I'll let you know ... this way you'll have a 2 year head start!