Fog build-up in Canon lens

Pretender · 12th December 2005

I took my D10 with a 28-200 Canon lens to Camera Workshop to check out the reason for my not so shrp pictures. They told me the lens has no fungi but it has a fog build-up int lens and there is nothing they can do about it. I could take it to Canon but I don't have warranty for it. Any body know anything about this? Is there anyway to fix it? Thanks.

P.S. I'm not saying the Camera Workshop guys are wrong or anything, they were very helpful. I just am asking if somebody found a work-around.

Belle&Sebastain · 12th December 2005

Originally Posted by Pretender

I took my D10 with a 28-200 Canon lens to Camera Workshop to check out the reason for my not so shrp pictures. They told me the lens has no fungi but it has a fog build-up int lens and there is nothing they can do about it. I could take it to Canon but I don't have warranty for it. Any body know anything about this? Is there anyway to fix it? Thanks.

P.S. I'm not saying the Camera Workshop guys are wrong or anything, they were very helpful. I just am asking if somebody found a work-around.

once fog, its not justifable to replace the elements for your lens as you may be better off buying a new one. There is no turnaround for fog lens, you need to replace the elements.

ShaoWei · 12th December 2005

Originally Posted by Pretender

I took my D10 with a 28-200 Canon lens to Camera Workshop to check out the reason for my not so shrp pictures. They told me the lens has no fungi but it has a fog build-up int lens and there is nothing they can do about it. I could take it to Canon but I don't have warranty for it. Any body know anything about this? Is there anyway to fix it? Thanks.

P.S. I'm not saying the Camera Workshop guys are wrong or anything, they were very helpful. I just am asking if somebody found a work-around.

I think for fog, you might have to change the elements itself and that as of my knowledge can only be done at canon service center (correct me if i'm wrong). just go there and ask like how much is it, i don't think it'll be cheap so u'll have to weigh the cost of getting a brand new or a 2nd hand lens in good condition to getting the fogged elements replaced. and ps, if they do a good job its fine, but i've heard of cases whereby lens getting all sorts of other problems like off calibration etc. after servicing.

holeinone · 12th December 2005

Any idea how long a lens can typically last before it fogs? I have one 14 year old Tamron lens that has fogged but my Canon 35-135 which is bought around the same time still has nice clean glass.

With so much investment into lenses nowadays, I certainly hope they don't deteriorate so quickly. Not sure if keeping them in a dry box is sufficient to prevent this from happening.

Pretender · 13th December 2005

Thanks for the info. Canon in Bangladesh won't bother looking into it as I don't think we have a local service centre. Just came back from Singapore so I could wait for my next trip but that could be months away. So I guess I need a new lens. Anyway, thanks for the help.

benedium · 13th December 2005

Really so bad ah? Can try to keep zooming in and out in dry aircon environment and see if it helps? Lastime i go beach and got sand into lens and i zoom in and out until no more sandy sound when i zoomed. Maybe dry air can get in and wet air can get out? Try before you spend money on repair loh.

szekiat · 13th December 2005

Its probably a coating fog. U can still get decently sharp photos on a fogged lens honestly. But i suppose it being on a 28-200 class probably doesn't help. Fog lenses can be fixed to a certain extent, but at the expense of the coating cos you will need to remove the lens coatings to even it out. i've had it done for me before on an old leica lens, not very expensive, but don't expect to retain the quality of the original lens. Its just a cheap workaround if u really have no money to repair or get a new one.

Goldenstars08 · 13th December 2005

The best way is to get a new one...

Ris Goh · 13th December 2005

if the fogging is on the glass surface its pretty cleanable (as long as the glass can be access easily).

if its enclosed in a plastic tube then you'll probably need to change the whole lens group.... this will have to be done at canon though and can be pretty expensive.

you might want to check if your 10D has some back/front focus problem also....

syl · 14th December 2005

I have a 70 - 200 mm f2.8L lens which I bought from eBay in USA. I was not happy with the quality of my pics compared to ny 70 - 200mm f4L lens (a lot lighter!). I brought it in to Canon at Harbour Front about 3 weeks ago. I got a call from them after a week saying that they needed to replace 2 groups of elements because of fogging and that the cost was about $500. I reluctantly agreed and when they called me 1 week later to collect, I was very disappointed that upon checking, my lens was almost in its original state - i.e. very badly fogged up, and obvioucly had not been serviced. The counter person took one look at it and immediately agreed with me. That was about 10 days ago and I'm still waiting for a collect call from them. It annoys me as I'm leaving for S. Africa in 1 week's time and would like to finish this episode before I leave. (BTW, I'll take the f4 with me becuz of the weight together with my 400mm f5.6L & the ext

enders.)

My point is:

1) They do accept lenses from elsewhere for cleaning and servicing;

2) It pays to check whether they have actually carried out the work that they are supposed to do.

3) Although the quoted price of $500 may be high, remember for that price you are geeting back an almost a new lens, with warranty at that too.

Only my 2c. worth.

jlchong · 15th December 2005

Hi guys,

pardon my ignorance.

how does fogging comes about? and how does it look like? if one faithfully keep his lenses in the dry cabinet, will it prevent fogging?

i have previously heard of and seen fungus before but never heard of fogging.

thanks in advance.

Ris Goh · 16th December 2005

There're some reasons that lens can fog up:

1. cement (clear) use to glue certain group of lens together may break down overtime and become whitish..... common for old lens that use organic base cement (eg. canadian balsam based cement use in Leica M3 rangefinders).

2. matt black paint use to coat the inside of the lens tube to reduce reflection may not have cured thoroughly before the lens was assembled... fumes from the paint can cause fogging on the surface of the glass, this is usually cleanable if it hasn't etched into the coating.

3. external source of fume.... certain plastic or synthetic rubber material that has not been cured thoroughly can also give off fumes that cause fogging after prolong exposure.

12th December 2005	#1
Pretender New Member Join Date: Dec 2005 Posts: 8	Fog build-up in Canon lens I took my D10 with a 28-200 Canon lens to Camera Workshop to check out the reason for my not so shrp pictures. They told me the lens has no fungi but it has a fog build-up int lens and there is nothing they can do about it. I could take it to Canon but I don't have warranty for it. Any body know anything about this? Is there anyway to fix it? Thanks. P.S. I'm not saying the Camera Workshop guys are wrong or anything, they were very helpful. I just am asking if somebody found a work-around. Last edited by Pretender; 12th December 2005 at 10:40 PM.

12th December 2005	#4
holeinone Member Join Date: Jan 2004 Location: Tampines Posts: 1,316	Re: Fog build-up in Canon lens Any idea how long a lens can typically last before it fogs? I have one 14 year old Tamron lens that has fogged but my Canon 35-135 which is bought around the same time still has nice clean glass. With so much investment into lenses nowadays, I certainly hope they don't deteriorate so quickly. Not sure if keeping them in a dry box is sufficient to prevent this from happening. __________________ There is no life without fast cars....

13th December 2005	#5
Pretender New Member Join Date: Dec 2005 Posts: 8	Re: Fog build-up in Canon lens Thanks for the info. Canon in Bangladesh won't bother looking into it as I don't think we have a local service centre. Just came back from Singapore so I could wait for my next trip but that could be months away. So I guess I need a new lens. Anyway, thanks for the help.

13th December 2005	#6
benedium Member Join Date: Jun 2004 Location: Upp Thomson Posts: 1,188	Re: Fog build-up in Canon lens Really so bad ah? Can try to keep zooming in and out in dry aircon environment and see if it helps? Lastime i go beach and got sand into lens and i zoom in and out until no more sandy sound when i zoomed. Maybe dry air can get in and wet air can get out? Try before you spend money on repair loh.

13th December 2005	#7
szekiat Senior Member Join Date: Jan 2002 Location: London Posts: 2,378	Re: Fog build-up in Canon lens Its probably a coating fog. U can still get decently sharp photos on a fogged lens honestly. But i suppose it being on a 28-200 class probably doesn't help. Fog lenses can be fixed to a certain extent, but at the expense of the coating cos you will need to remove the lens coatings to even it out. i've had it done for me before on an old leica lens, not very expensive, but don't expect to retain the quality of the original lens. Its just a cheap workaround if u really have no money to repair or get a new one.

13th December 2005	#8
Goldenstars08 Member Join Date: Nov 2004 Location: Singapore Posts: 1,139	Re: Fog build-up in Canon lens The best way is to get a new one... __________________ Photography first, Food always.

13th December 2005	#9
Ris Goh Member Join Date: Jul 2004 Posts: 750	Re: Fog build-up in Canon lens if the fogging is on the glass surface its pretty cleanable (as long as the glass can be access easily). if its enclosed in a plastic tube then you'll probably need to change the whole lens group.... this will have to be done at canon though and can be pretty expensive. you might want to check if your 10D has some back/front focus problem also....

14th December 2005	#10
syl Member Join Date: Nov 2005 Location: Singapore Posts: 832	Re: Fog build-up in Canon lens I have a 70 - 200 mm f2.8L lens which I bought from eBay in USA. I was not happy with the quality of my pics compared to ny 70 - 200mm f4L lens (a lot lighter!). I brought it in to Canon at Harbour Front about 3 weeks ago. I got a call from them after a week saying that they needed to replace 2 groups of elements because of fogging and that the cost was about $500. I reluctantly agreed and when they called me 1 week later to collect, I was very disappointed that upon checking, my lens was almost in its original state - i.e. very badly fogged up, and obvioucly had not been serviced. The counter person took one look at it and immediately agreed with me. That was about 10 days ago and I'm still waiting for a collect call from them. It annoys me as I'm leaving for S. Africa in 1 week's time and would like to finish this episode before I leave. (BTW, I'll take the f4 with me becuz of the weight together with my 400mm f5.6L & the ext enders.) My point is: 1) They do accept lenses from elsewhere for cleaning and servicing; 2) It pays to check whether they have actually carried out the work that they are supposed to do. 3) Although the quoted price of $500 may be high, remember for that price you are geeting back an almost a new lens, with warranty at that too. Only my 2c. worth.

15th December 2005	#11
jlchong Member Join Date: Aug 2004 Location: Redhill Posts: 435	Re: Fog build-up in Canon lens Hi guys, pardon my ignorance. how does fogging comes about? and how does it look like? if one faithfully keep his lenses in the dry cabinet, will it prevent fogging? i have previously heard of and seen fungus before but never heard of fogging. thanks in advance.

16th December 2005	#12
Ris Goh Member Join Date: Jul 2004 Posts: 750	Re: Fog build-up in Canon lens There're some reasons that lens can fog up: 1. cement (clear) use to glue certain group of lens together may break down overtime and become whitish..... common for old lens that use organic base cement (eg. canadian balsam based cement use in Leica M3 rangefinders). 2. matt black paint use to coat the inside of the lens tube to reduce reflection may not have cured thoroughly before the lens was assembled... fumes from the paint can cause fogging on the surface of the glass, this is usually cleanable if it hasn't etched into the coating. 3. external source of fume.... certain plastic or synthetic rubber material that has not been cured thoroughly can also give off fumes that cause fogging after prolong exposure.