Lens separation - how does it affect images?

[Niels - NHSN]

I thought others here might find the results below interesting. And I would be interested in hearing your experiences with the effects of lens separations, should you have any such first hand.

I had an opportunity to borrow a Rolleiflex 3.5 E2 with a Carl Zeiss Planar lens suffering from servere separation in the front group - probably covering 50% of the inner surface area.
I was curious to see how or if it would affect the results, primarily sparked by some individuals who claimed the camera only had value as a parts source.

I informally ran a roll of Kodak Gold 200 through the camera. Deliberately trying to challenge the lens for potential flare faults - including dominant bright areas of light as well as shots wide open to make sure the edges of the lens where in play.

A click on the image will take you to a larger version on Flickr.

Scans are all as they came to me from the lab - no additional processing on my end.

The Camera:

 

The separation can be difficult to see but appear to be covering about 50% running along the edges:

 

Example photos

1/15 f3.5 Table top tripod, Kodak Gold 200:

 

1/250 f8 Handheld, Kodak Gold 200:

 

1/500 f8 Handheld, Kodak Gold 200:

 

1/250 f/3.5 Handheld, Kodak Gold 200:

 

1/250 f5.6 Handheld, Kodak Gold 200:

 

1/125 f8 Handheld, Kodak Gold 200

 

To my eyes, this is a very useable camera.

Edited October 25, 2023 by Niels - NHSN

[arthur_mcculloch2]

Thanks for posting these images, Niels.  I'd agree with you.  Where I'd expected something obvious to show up, it didn't.  I'd be interested in hearing other thoughts and experiences. Regards, Arthur.

[John Seaman]

3 hours ago, Niels - NHSN said:

To my eyes, this is a very useable camera.

Yes Niels. Your results don't suggest ant detriment to image quality. It's a shame any kind of lens defect often results in the collapse of the camera's monetary value. On the other hand it may be possible to acquire a perfectly usable camera at reduces price. Thanks for posting.

[James Bryant]

Interesting. I expected it to show obvious image loss of quality.

 

[dan_fromm2]

That's all well and good, but the effect depends on the separation and the lens.

The OP's lens shows classic rings of fire.

Item, my 58/5.6 Grandagon, whose separations manifest as silver spots near the center of the lens and rings of fire at the periphery.  No effect.  The lens is very usable.

Item, my 25-15 wide angle attachment for a 25/1.4 Cine Ektar, whose separations show as strong broad Newton's rings.  In footage shot with it, the rings are clearly visible.  The attachment is unusable.  I have another 25-15 with no separations.  Footage shot with it doesn't have visible rings.

When in doubt, test.

Edited October 25, 2023 by dan_fromm2

[bruce_z._li2]

Hi Niels,

Thanks for sharing the results. Yes your Planar is very usable, and the separation's impact is very minor if any.

I had two related experience:

1) Voigtlander Septon 50/2 (for Bessamatic/Ultramatic), wide ring around the edge, about 50% of surface area. If the sun is behind me or to the side of me, there is little discernible effect. But if I shoot straight into the sun, there is some veiling flare. I don't know if it was the separation or the lens design itself, since I don't have a good copy of Septon to compare.

2) Zeiss Sonnar 85/2 for Contarex, narrow ring around edge, about 25% of surface area. I cannot see much effects on the image quality, backlit or frontlit. And I use that lens wide open a lot.

Edited October 25, 2023 by bruce_z._li2

[stephen_mcateer]

These photographs look fine to me Niels. I don't see any problem, though I would have expected something to show up. (I'm off to check the price of Gold 200 — it has to be cheaper than Portra 400, which is what I've been using lately / £14 per roll.)

[Niels - NHSN]

9 hours ago, stephen_mcateer said:

(I'm off to check the price of Gold 200 — it has to be cheaper than Portra 400, which is what I've been using lately / £14 per roll.)

Where I live Gold 200 is about 25-30% cheaper than Portra 160. Haven’t checked Portra 400.

[stephen_mcateer]

10 hours ago, Niels - NHSN said:

Where I live Gold 200 is about 25-30% cheaper than Portra 160. Haven’t checked Portra 400.

Yes — I'm in the UK and it looks like Gold is ~£50 for 5 rolls of 120, versus ~£80 for Portra 400. (I'm thinking I might try a roll of Portra 160 and see how I get on with it. The slower shutter speeds it would require is what put me off up till now.)