Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-02-2013, 03:32 PM   #1
Veteran Member
NitroDC's Avatar

Join Date: Jun 2009
Posts: 342
MX and an infected 50mm

So I bought an MX (in very good condition) bundled with a 50mm f/1.7 with a net of fungus over one of the rear elements. I'm slightly afraid of leaving this lens on the camera as I might want to keep the MX (got it for a very good price) for film endeavors. I put it up on eBay for $30/auction but no one seems to be going for it. Wanted to put it here but don't have supporter status. Anyways, what should I do? Will anyone buy a lens with dust and fungus (even though build wise it it excellent and IQ doesnt seem to be affected)? Here are some photos from my listing.




The fungus looks bad compared to some online shots where they only form a small spot. There is literally a widespread net of it all across (and a thick spot in the bottom left corner). So I have pretty low hopes of selling this lens.
I don't know if I should keep trying to sell or just give it to goodwill or something. I don't want to keep it at all since I already have a clean version of this exact lens, and I don't want my other lenses getting "infected".

As a side question, how much is an MX usually worth in full working condition and good cosmetics?


Last edited by NitroDC; 02-02-2013 at 03:43 PM.
02-02-2013, 04:18 PM   #2
Site Supporter
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,825
QuoteOriginally posted by NitroDC Quote
I don't want my other lenses getting "infected".
This is an internet myth. It will not, actually CANNOT infect your other lenses, because it is already dead. if it was still growing you would have a white ball of fungus covering the entire lens inside and out, not a lens with some mycelium on it.

But to answer your question, yes some will buy it and clean. it I have bought several lenses and done so. The problem is that this lens is very common and sells for maybe $50 on a regular basis. Figuring several hours work to clean it, why would I spend anything on it when I can get a mint one for a few dollars more. If it was a rare or valuable lens then yes it would sell and it would be worth the time and money to clean. In this case sadly, not so.
02-02-2013, 04:19 PM   #3
Pentaxian
Na Horuk's Avatar

Join Date: Feb 2012
Location: Slovenia, probably
Photos: Gallery | Albums
Posts: 10,925
You can make sure the camera isn't infected.. and send the 50mm off to a pro for cleaning (tell the shop about the fungus ahead of time). That 50mm lens is fine, so fixing it up might be worth your while. (That M 50mm f1.7 lens goes for $50-100)
02-02-2013, 04:38 PM   #4
Veteran Member
kcobain1992's Avatar

Join Date: Dec 2010
Location: Bucharest, Romania
Photos: Gallery
Posts: 1,409
Don't be afraid - that's a reasonable amount of fungus, and it won't bother you, until you are ready to clean it. My girlfriend's MX + 50/1.7 was bought in similar condition and cleaned by a pro after half an year. Cost around $20 - not that image quality improved from the cleaning, but it stood on my mind, so I know what it's like. So wait patiently for the opportunity to clean it/have it cleaned.

02-02-2013, 04:54 PM   #5
Inactive Account




Join Date: Dec 2008
Location: North Carolina
Photos: Albums
Posts: 1,720
I'd buy it, but not for very much over the cost of shipping it.
02-02-2013, 05:29 PM   #6
Veteran Member
NitroDC's Avatar

Join Date: Jun 2009
Posts: 342
Original Poster
Is it difficult to take apart, clean, and put it back together? I've looked around but there seem to be no camera repair shops anywhere within an hour drive.
02-02-2013, 08:15 PM   #7
Site Supporter
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,663
Yes, the fungus may be dead, but the spores (which are highly resistant) are pretty much immortal. I would personally consider it to be potentially infectious and suggest putting it is a zip-lock bag until you figure out what to do with it and wash your hands afterward.

When you have the camera CLA'd, mention the fungus lens. The tech should be able to remove any fungus that may be present on the mirror, screen, pentaprism or ocular. As for servicing the lens itself, some members here have reported some success with fungus removal. I would caution that etching of the coatings and/or glass by the fungus is probable. I would also caution that removal may not be easy. I have personally purchased (and returned) lenses that had deep permanent cleaning scratches on internal elements due to fungus removal...and yes, those scratches did affect lens performance.

In regards to self-service...with appropriate tools, solvents, lubricants, and a steady hand, lens repair is not that difficult. I would check into finding another M 50/1.7. They are not uncommon and usually fairly reasonably priced.


Steve
02-02-2013, 08:43 PM   #8
Site Supporter
Site Supporter




Join Date: Jun 2009
Location: Indiana PA USA
Posts: 1,346
Jatrax
QuoteOriginally posted by jatrax Quote
This is an internet myth. It will not, actually CANNOT infect your other lenses, because it is already dead. if it was still growing you would have a white ball of fungus covering the entire lens inside and out, not a lens with some mycelium on it.
I'm curious why you say this. I work with fungi professionally - although not specifically those that grow on lenses - and know that the growth rate is tied to the nutrient availability and "hospitality" of the environment. Concluding that it's dead simply because the lens isn't a fluffy ball seems a bit of a leap.

Likewise, as stevebrot (correctly) says, the fungal spores exist long after the mycellia has become inactive. And at least for the species I use, sporulation is more likely when the fungi grows on a "lean" media - which, likely, lens' glues are. I agree that the likelihood of one lens infecting another is small, I don't agree that "This is an internet myth." I have too much trouble with Neurospora contaminations in our Trichoderma cultures. I don't have proof, but I believe the Neurospora comes from ten-year old spores from a now-retired colleague's work with that species.

I'm not trying to cause a war - I'm just curious why you made the conclusions you stated.

Thanks.

02-02-2013, 09:15 PM   #9
Veteran Member
NitroDC's Avatar

Join Date: Jun 2009
Posts: 342
Original Poster
Thanks for all the advice. I do already have an M 50/1.7. This one just came bundled with the MX. I just don't know what to do with it.

So the camera itself can be a "carrier" of the fungus then? I checked the inside with a flashlight and it seems pretty clean. Some dust but nothing that looks like fungus. I keep a few silica bags in my camera bag, will that help prevent any growth in the rest of my lenses? It needs moisture to grow, right?
02-02-2013, 09:42 PM   #10
Site Supporter
Site Supporter




Join Date: Jun 2009
Location: Indiana PA USA
Posts: 1,346
QuoteOriginally posted by NitroDC Quote
Thanks for all the advice. I do already have an M 50/1.7. This one just came bundled with the MX. I just don't know what to do with it.

So the camera itself can be a "carrier" of the fungus then? I checked the inside with a flashlight and it seems pretty clean. Some dust but nothing that looks like fungus. I keep a few silica bags in my camera bag, will that help prevent any growth in the rest of my lenses? It needs moisture to grow, right?
Yes, fungus needs moisture to grow. Make certain your silica is dry by periodically drying the packet itself - some types can be placed in a 250 F oven overnight to dry the silica. Be careful, though, because not all silica packets are safe to dry - it depends on the packaging. Silica is stable to its melting point. (Over, actually.)

The "seed" of a fungus is a spore - a dust-sized little packet of life-to-be. Spores are tough - you can kill the fungus with boiling water (100 C) but it takes an autoclave - wet heat at 121 C - to kill the spores. Or 70% alcohol (don't use 91% or 100%, because that can actually dehydrate and preserve the spores, at least for certain bacteria - not sure about fungal spores).

So, yes, your MX COULD potentially now have fungal spores which could contaminate another lens. But probably not. It would require movement of the spores from the contaminated lens into the camera - and I don't know any details of lens design, so I can't comment on how easy it might be to have air movement from the inside of the contaminated lens into the camera body by focusing, zooming, or even just mounting a lens. And then you'd have to have movement of the spores from the comtaminated, "carrier" camera back into a new lens. It's not impossible - just improbable.

Fungal spores are common in the environment, so as was mentioned in another thread on fungus (there's several on the forum), if you keep lenses stored in a clean and dry place, it's probably as likely to get random environmental spores as spores from another lens. Personally, I think that's probably true. But a fungus growing on a lens certainly gives off spores capable of growing on a lens, while a random environmental spore may or may not.

FWIW
02-03-2013, 12:05 AM - 1 Like   #11
Site Supporter
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,825
QuoteOriginally posted by jford Quote
I'm curious why you say this. I work with fungi professionally - although not specifically those that grow on lenses - and know that the growth rate is tied to the nutrient availability and "hospitality" of the environment. Concluding that it's dead simply because the lens isn't a fluffy ball seems a bit of a leap. Likewise, as stevebrot (correctly) says, the fungal spores exist long after the mycellia has become inactive. And at least for the species I use, sporulation is more likely when the fungi grows on a "lean" media - which, likely, lens' glues are. I agree that the likelihood of one lens infecting another is small, I don't agree that "This is an internet myth." I have too much trouble with Neurospora contaminations in our Trichoderma cultures. I don't have proof, but I believe the Neurospora comes from ten-year old spores from a now-retired colleague's work with that species. I'm not trying to cause a war - I'm just curious why you made the conclusions you stated. Thanks.
My background is also in biology, and my answer was perhaps less than precise. It is just that this myth of lenses infecting others seems to come up again and again and it is untrue. Layman seem to think the mycellium will grow out of the lens across their camera bag and into another lens. My reference to a fluffy ball, while an attempt to be humorous, was simply trying to point out that fungus does not stop growing until it runs out of something it needs to grow. So if it was 'live' then it would still be growing. The spores are indeed another story.

As both you and Steve pointed out spores last a very long time. In addition they are present in most environments. So it is safe to say that spores of one type or another are already in the lenses and other equipment we have. As you correctly stated the growth is almost exclusively governed by the presence of water and nutrients. In lenses, the regulating condition is almost always water as it is used up before potential nutrients are. In my experience with camera lenses the fungus continues to grow as long as water and nutrients are present and then it stops. The mycellium then dies although of course spores are still going to be present.

New spores, formed by the fungus growing in the lens, are rare, in fact I have never seen fruiting bodies present in any lens infected with fungus because usually the fungus uses up the available moisture quite quickly and dies before it reaches a fruiting stage. I am not saying this is not possible, only that I have not observed or seen pictures of such an event.

My primary point is that all lenses are already, probably, infected by fungal spores and only keeping your gear dry will prevent it from growing. The new WR lenses may be sealed better and may have less of an opportunity to become infected with spores but even they I suspect will have spores present if tested. My DA*16-50 pumps air in and out with each actuation of the zoom thus moving air and the dust & spores it contains into the lens.

Like all myths there is a grain of truth here but saying that having a fungus infected lens in close proximity to another lens will increase the possibility that it will be infected is just not true. There is a high probability that the other lens is already infected, but as long as it stays dry, you will never see any fungal growth.

I think the reason this is one of my hot buttons is that keeping your gear dry is the only thing needed to prevent fungus growth, and allowing people to think that keeping infected lenses away from their gear will keep it from being infected is just giving them a false sense of security. If they get water in their gear there is a high probability that fungus will grow, whether it has been near an 'infected' lens or not. I have bought a number of old camera kits at estate sales and often there will be a lens with fungus growth. Some of these kits have been stored away for 10 or more years with a number of lenses all packed together in the same bag, but only one has fungus. If close proximity to an infected lens had any relationship to a lens getting fungus surely these lenses would all have fungus?

Sorry for the long post, I hope that explains my thoughts. And I will try to be more precise in the future instead of dashing off a careless reply.
02-03-2013, 04:02 AM   #12
Veteran Member
kcobain1992's Avatar

Join Date: Dec 2010
Location: Bucharest, Romania
Photos: Gallery
Posts: 1,409
I think Jatrax is right. Fungus spores are everywhere in the air, you should not obsess about them.

QuoteOriginally posted by NitroDC Quote
So the camera itself can be a "carrier" of the fungus then? I checked the inside with a flashlight and it seems pretty clean. Some dust but nothing that looks like fungus. I keep a few silica bags in my camera bag, will that help prevent any growth in the rest of my lenses? It needs moisture to grow, right?
No, that is not correct. Fungus will grow on anything that is organic. Especially dust. That's how it grew on the inside of the lens in the first place.

Last edited by kcobain1992; 02-03-2013 at 04:08 AM.
02-03-2013, 08:08 AM   #13
Veteran Member
womble's Avatar

Join Date: Apr 2010
Location: Hertfordshire
Photos: Gallery
Posts: 1,326
If you don't need it and do not want to pay for it to be cleaned, put the lens on ebay with a 99c starting price. I've often observed that auctions with a relatively high starting price compared to value do not do well, whereas 99c starting price auctions often do quite well. You'll probably still get something for it, but possibly not the $30 you were hoping for.

Otherwise, get it cleaned and use it.

The MX will be fine if you keep it dry, and not just because of the fungus but just because cameras and moisture are generally a bad combination.

K.
02-03-2013, 02:20 PM - 1 Like   #14
Site Supporter
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,663
QuoteOriginally posted by jford Quote
But a fungus growing on a lens certainly gives off spores capable of growing on a lens, while a random environmental spore may or may not.
My background is also in biology/botany and while not a mycologist, I have a terrific respect for the longevity and infectivity of fungal spores. I also have terrific respect for specialized organisms that occupy unusual and/or highly unfriendly niches. As such, I prefer to keep such known and proven infectious agents away from my uninfected lenses.


Steve
02-03-2013, 03:57 PM   #15
Site Supporter
Site Supporter




Join Date: Jan 2010
Location: Michigan
Photos: Gallery
Posts: 2,200
So how long does it take for a wet lens to become damaged by fungus?
I was in Thailand recently and took the Rikenon out of the cool hotel room 5:00 am for some shots whereupon it and the camera drastically fogged up.
I suppose this happens at each leaving of an aircon environment. Is the fungus growth cumulative or does it need some time to get started each time?
: thanks for the info so far
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
50mm, condition, fungus, lens, mx, spot
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Do I need an MX? Vendee Pentax Film SLR Discussion 36 01-15-2013 09:58 PM
Need some help with an MX! Jonathan Mac Troubleshooting and Beginner Help 5 03-15-2012 02:20 PM
Wanted - Acquired: Pentax MX, SMC-M 50mm/1.7 and SMC 28mm/2.8 timbo10ca Sold Items 2 11-18-2009 02:42 PM
Pondering on an MX and Film Development PollitowuzHere Pentax Film SLR Discussion 19 12-05-2008 12:04 PM



All times are GMT -7. The time now is 06:16 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top