The perils of living in the tropics

[RBruceCR]

Chaps:

I discovered fungi (or balsam separation) on the inside rear element of my Sekor 90/3.5. I took it to a local shop and they cleaned it, very efficiently and swiftly, but the trace of the fungi is still visible, not as before when it was cloudy.

I contacted Tony Sansone to find if he had a rear element that I could buy to replace mine. He helped me identify and fix a light leak that plagued this camera for the last 30 years.

The question that I have (for the sake of conversation) is if it really matters to have a perfect rear element or to get another used 90/3.5 on eBay at $159 or even another focal length such as a 100/3.5 (went for $99 in Japan) despite the fact that the viewfinder is calibrated for the 90/3.5, will it really matter? I guess I'll have to wait for Tony's quotation.

The pictures come with good contrast scanned right off the film as the lens was. Now it's less cloudy but you can still see the trace of the damage. I don't know if the damage will show on a print enlargement or not. Perhaps you can chip in!

Regards,

 

[hamradio]

I have to imagine the difference in framing with the 100 to be fairly small...does the Standard 23 have framelines in the VF?

 

[Pablito]

There is no way to avoid fungus in the tropics. You can use a dry box, but obviously the lenses are not going to be in there all the time. Also, fungus likes the dark. Bright light helps prevent fungus.

In my experience, a lens infected with a moderate amount of fungus can still produce sharp and contrasty images, but each case is unique....

 

[RBruceCR]

I have to imagine the difference in framing with the 100 to be fairly small...does the Standard 23 have framelines in the VF?

No, it doesn't! The Standard 23 has viewfinder masks!

I'm trying to find the different angles of view of the lenses. Perhaps it was a manual at Butkus!

Regards,

Robert

 

[RBruceCR]

There is no way to avoid fungus in the tropics. You can use a dry box, but obviously the lenses are not going to be in there all the time. Also, fungus likes the dark. Bright light helps prevent fungus.

In my experience, a lens infected with a moderate amount of fungus can still produce sharp and contrasty images, but each case is unique....

Indeed! The camera was left in its bag, more of a suitcase, for over 30 years.

 

[jarski]

learned the curse of fungus, after moving to Thailand. my lenses were cheap Takumars though, and fungus didn't have enough time to penetrate inside before noticed and cleaned it. forgetting lens in a bag where air does not circulate is guaranteed way of getting fungus on it. decent AC helps. dry box is a must for expensive glass.

 

[RBruceCR]

learned the curse of fungus by the hard way, after moving to Thailand. my lenses were cheap Takumars though, and fungus didn't have enough time to penetrate inside the lens before I discovered and cleaned it. forgetting lens inside a bag where air does not circulate at all is guaranteed way of getting fungus on it. decent AC helps. dry box is a must for expensive glass.

The "silcagel" bags don't seem to do much!

 

[Scrambler]

Chaps:

I discovered fungi (or balsam separation) on the inside rear element of my Sekor 90/3.5. I took it to a local shop and they cleaned it, very efficiently and swiftly, but the trace of the fungi is still visible, not as before when it was cloudy.

I contacted Tony Sansone to find if he had a rear element that I could buy to replace mine. He helped me identify and fix a light leak that plagued this camera for the last 30 years.

The question that I have (for the sake of conversation) is if it really matters to have a perfect rear element or to get another used 90/3.5 on eBay at $159 or even another focal length such as a 100/3.5 (went for $99 in Japan) despite the fact that the viewfinder is calibrated for the 90/3.5, will it really matter? I guess I'll have to wait for Tony's quotation.

The pictures come with good contrast scanned right off the film as the lens was. Now it's less cloudy but you can still see the trace of the damage. I don't know if the damage will show on a print enlargement or not. Perhaps you can chip in!

Regards,

It takes a lot of damage to make a clear difference to the negative, let alone the print. The main issue is with flare, or light scattering.

We tend to imagine that light travels in an orderly fashion through the lens onto the film, point-to-point. In fact light from the entire image strikes every point of the front element and is refracted differently though the lens. For lenses with a long distance between rear element and the film plane there is little obvious impact from even rear element damage in terms of issues at a particular location on the negative. What there is, though, is scattering of light all over the film plane. Coating damage on the rear element may make internal reflections more likely as well, further adding to flare.

The main thing I would recommend is getting good humidity control for the lenses in storage, and occasional UV exposure to inhibit growth of further organisms. A day's full sunlight exposure will disinfect a 2L/ 1 quart PET bottle of water and it's pretty good for killing lens fungus as well.

 

[KevinVH]

Ok so since I'm living in Ecuador, and keeping my lenses in a Pelicase in the attic, This topic has got me worried.

Since they broke in a previous apartment here in Ecuador, I keep my D800 with all the lenses in a black Pelicase in a secret 3rd floor in my new house. The 3th floor is nothing more then a space between the ceiling of the 2nd floor, and the roof. The roof isn't isolated, so on a sunny day, temperatures can rise up to 40 degrees centigrade. I do have some silicone bags in the case, and I imagine the case itself is pretty temperature resistant, but should I be worrying about my gear?

 

[RBruceCR]

It takes a lot of damage to make a clear difference to the negative, let alone the print. The main issue is with flare, or light scattering.

We tend to imagine that light travels in an orderly fashion through the lens onto the film, point-to-point. In fact light from the entire image strikes every point of the front element and is refracted differently though the lens. For lenses with a long distance between rear element and the film plane there is little obvious impact from even rear element damage in terms of issues at a particular location on the negative. What there is, though, is scattering of light all over the film plane. Coating damage on the rear element may make internal reflections more likely as well, further adding to flare.

The main thing I would recommend is getting good humidity control for the lenses in storage, and occasional UV exposure to inhibit growth of further organisms. A day's full sunlight exposure will disinfect a 2L/ 1 quart PET bottle of water and it's pretty good for killing lens fungus as well.

Thanks for the well grounded explanation. I will run a few frames to decide if it's better to find a new to me lens or to have this one fixed.

 

[RBruceCR]

Ok so since I'm living in Ecuador, and keeping my lenses in a Pelicase in the attic, This topic has got me worried.

Since they broke in a previous apartment here in Ecuador, I keep my D800 with all the lenses in a black Pelicase in a secret 3rd floor in my new house. The 3th floor is nothing more then a space between the ceiling of the 2nd floor, and the roof. The roof isn't isolated, so on a sunny day, temperatures can rise up to 40 degrees centigrade. I do have some silicone bags in the case, and I imagine the case itself is pretty temperature resistant, but should I be worrying about my gear?

I'm not sure high temperatures are good for the balsam cementing together your lenses, and high temperature could me as well high humidity, however, Ecuador depending where do you live might be different except for the port city of Guayaquil.

 

[Eugen Mezei]

This being a D800 I guess it has modern lenses, so no (canada)balsam in there.
Are modern glue prone to temperature or once they are hardened they will not be affected?

 

[KevinVH]

I'm up in the mountains in Cuenca, but since the 3rd floor is completely sealed temperatures rise up there. I guestimate up to 104F, maybe a little hotter, but there is no direct sunlight on the black pelicase. I'll take it out tomorrow at midday to see if the case inside gets hot. The lenses are all modern lenses, 24-70 and 14-24

 

[Johann Espiritu]

I live in the Philippines, and keep my lenses in a dry box. So far, no problems.

 

[f16sunshine]

Heat is not so good either. Semi-Solid Lubricants will become too liquid and "melt" into places they do not belong.
Other problems can occur as well. A dry box is a better alternative rather than storing in high heat.

 

[xdayv]

I use a drybox, it's been effective. Silica gels for the photo bags also help. But drybox is the primary storage.

 

[charjohncarter]

I lived in Panama' and had full central air conditioning in my home. I bought a Konica C35 when I was there (new). It stopped working after I returned to the USA, I so I opened it. It was completely filled with white mold. So much for air conditioning helping as I thought.

 

[Johann Espiritu]

So much for air conditioning helping as I thought.

A/C + humidity just makes the air more damp, so I think it actually makes it worse.

An occasional "sunning" by the window helps a lot in keeping fungus away too. Dark + damp = molds!

 

[RBruceCR]

We still run a yellow light computer to plate machine in our shop in a former dark room, with A/C and dehumidifier, so it's true John, A/C is only good for the electricity utility in Costa Rica, and a matter of life and death in Panamá City!

So I believe that I will shoot some test pictures before committing to another lens and keep the lens hood always on!

 

[Pablito]

Ok so since I'm living in Ecuador, and keeping my lenses in a Pelicase in the attic, This topic has got me worried.

Since they broke in a previous apartment here in Ecuador, I keep my D800 with all the lenses in a black Pelicase in a secret 3rd floor in my new house. The 3th floor is nothing more then a space between the ceiling of the 2nd floor, and the roof. The roof isn't isolated, so on a sunny day, temperatures can rise up to 40 degrees centigrade. I do have some silicone bags in the case, and I imagine the case itself is pretty temperature resistant, but should I be worrying about my gear?

Heat is very destructive to photo equipment... this is a very bad idea...