Kevin Crisp
30-May-2024, 07:58
A recent lesson in not giving up on post-balsam lenses that have some.
I bought a Rolleiflex with the 3.5 planar. My repair guy after the CLA told me it had separation and it was going to affect the negatives. I shot some film with it and he was sure right, the highlights were fuzzed up, and not in a way I thought would be useful in the future.
Looking through the lens it seemed to me that the main problem was "cleaning marks" (aka scouring) of the front element. It was bad, and there was a permanent finger print in the middle. And with the front element unscrewed from the camera I could clearly see the separation in the rear element. At certain angles, an amoeba-like area that covered at least 40% of the rear element could be seen. At one point the affected area extends into the middle of the rear element. Looking straight on it was hard to notice, but obvious with a light at certain angles. It looked like the rear element had a pattern of clear liquid on it. I figured I could DIY recement the rear element eventually, so I removed the scoured front element and had it polished and recoated.
I got the repaired front element back (looking better than new, at a cost almost equal to the purchase price of the camera...) and reassembled the lens. I have a couple rolls of Fomapan 100 I haven't tried so I shot two rolls with it yesterday. One in low contrast on an overcast morning and one in bright sun. The negatives are just stunningly sharp and contrasty. I couldn't get the lens to misbehave in any way. Even wide open at f:3.5 they look terrific.
So don't give up on a modern lens with some separation. Buying one with the problem might still be a pig in a poke, but if one of yours suffers from it, give it a fair try and don't assume it needs to be perfect.
None of this applies to balsam-cemented lenses. They tend to fail most often on the edges and at typical LF apertures they may still be fine. But they don't separate graciously like the modern UV-cure cemented lenses can. The balsam gets yellow/brown and crusty, like dried up maple syrup.
Fomapan 100 seems like a nice film.
I bought a Rolleiflex with the 3.5 planar. My repair guy after the CLA told me it had separation and it was going to affect the negatives. I shot some film with it and he was sure right, the highlights were fuzzed up, and not in a way I thought would be useful in the future.
Looking through the lens it seemed to me that the main problem was "cleaning marks" (aka scouring) of the front element. It was bad, and there was a permanent finger print in the middle. And with the front element unscrewed from the camera I could clearly see the separation in the rear element. At certain angles, an amoeba-like area that covered at least 40% of the rear element could be seen. At one point the affected area extends into the middle of the rear element. Looking straight on it was hard to notice, but obvious with a light at certain angles. It looked like the rear element had a pattern of clear liquid on it. I figured I could DIY recement the rear element eventually, so I removed the scoured front element and had it polished and recoated.
I got the repaired front element back (looking better than new, at a cost almost equal to the purchase price of the camera...) and reassembled the lens. I have a couple rolls of Fomapan 100 I haven't tried so I shot two rolls with it yesterday. One in low contrast on an overcast morning and one in bright sun. The negatives are just stunningly sharp and contrasty. I couldn't get the lens to misbehave in any way. Even wide open at f:3.5 they look terrific.
So don't give up on a modern lens with some separation. Buying one with the problem might still be a pig in a poke, but if one of yours suffers from it, give it a fair try and don't assume it needs to be perfect.
None of this applies to balsam-cemented lenses. They tend to fail most often on the edges and at typical LF apertures they may still be fine. But they don't separate graciously like the modern UV-cure cemented lenses can. The balsam gets yellow/brown and crusty, like dried up maple syrup.
Fomapan 100 seems like a nice film.