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View Full Version : Coating a Cooke Portrait Lens, is there any benefit?



Colin D
9-Feb-2016, 18:36
I'm wondering if there is any benefit in coating my Servies VI Cooke Portrait lens to do colour photography. I've received a cost from Cooke which is prohibitive in itself but still the notion of coating it has raised the issue of whether it would be beneficial or not beneficial. That is, is there something about the lens taking ability or design that makes it a nonsense to coat just to be able to shoot colour as well. For instance might it diminish the quality or appearance of b&w images if you coat the lens. Or is soft focus photography in colour unusual, difficult for a particular reason which makes it unrealistic to consider doing.

Mark Sawyer
9-Feb-2016, 19:40
Coating the lens will reduce lens flare, increase the contrast a bit, and keep the shadows a little cleaner, whether b/w or color. That's about it. Whether that's important to you depends mostly on you.

Jason Greenberg Motamedi
9-Feb-2016, 20:05
I have a 1870s Dallmeyer Petzval that I had coated 10 years ago when AraxFoto in the Ukraine was doing it very cheaply. The balsam had completely failed, so it had little value, and sending it to AraxFoto was a fun experiment. The lens can back multicoated and recemented. I can't tell you the unique differences to this lens, as it wasn't usable before, but in comparison to a similar lens (same size, same era, same model), it is noticeably more contrasty and flare resistant. The contrast does remove some of the typical "period" look, but that is about it. I would think that coating might remove some of the typical "Cooke" look which seems to be about gray scale.

Peter De Smidt
9-Feb-2016, 20:05
Mark's right. Personally, I wouldn't worry about it. One of the reasons to shoot old lenses is that they produce a different look than current ones.

Colin D
10-Feb-2016, 01:01
Thanks guys for your thoughts. Which leads me to the next question, if the lens is coated just how much of that antique/period look will it lose in the b&w images which is where I gather the change is most noticeable. It's probably a subjective question but what is the feeling. Does it all of a sudden produce images that look nothing like they once did, or are we talking narrow margins of difference with a similar but not the same result.

LabRat
10-Feb-2016, 04:08
If the lens surfaces have a slight tarnish/oxidation (bloom) that you can see, that is already a form of lens coating...

If the surfaces have a whitish haze, that cuts contrast a lot, but can often be cleaned in a ultrasonic cleaner to clear again...

Steve K

Colin D
10-Feb-2016, 04:37
If the lens surfaces have a slight tarnish/oxidation (bloom) that you can see, that is already a form of lens coating...

If the surfaces have a whitish haze, that cuts contrast a lot, but can often be cleaned in a ultrasonic cleaner to clear again...

Steve K

When it arrived I had the lens cleaned professionally because the glass was a mess, I'm assuming that it should have little of what you describe.

Michael E
10-Feb-2016, 09:18
I'm wondering if there is any benefit in coating my Servies VI Cooke Portrait lens to do colour photography. I've received a cost from Cooke which is prohibitive in itself

Have you shot a box of color film with the lens? If so, do you miss a coating? Are the images inferior? If the images are OK, you can save yourself the investment. What do you need to achieve? You sound like you don't know what you can expect from coating.

How do do process your images? If you scan your negatives and continue in Photoshop, you can fix a lot of issues of an uncoated lens in post production. You can add contrast and saturation, but you can't (easily) fix lens flare.

Colin D
10-Feb-2016, 13:57
Have you shot a box of color film with the lens? If so, do you miss a coating? Are the images inferior? If the images are OK, you can save yourself the investment. What do you need to achieve? You sound like you don't know what you can expect from coating.

How do do process your images? If you scan your negatives and continue in Photoshop, you can fix a lot of issues of an uncoated lens in post production. You can add contrast and saturation, but you can't (easily) fix lens flare.

You're right, I haven't shot with it in colour but have been meaning to do so just to see. From what I've read previously though I thought uncoated lenses did something weird to colours, but then again I've never tried it to see for myself.

Mark Sawyer
10-Feb-2016, 16:40
The coatings are only to reduce reflections from lens surfaces, especially the internal air-glass surfaces.

Jim Noel
10-Feb-2016, 16:42
You're right, I haven't shot with it in colour but have been meaning to do so just to see. From what I've read previously though I thought uncoated lenses did something weird to colours, but then again I've never tried it to see for myself.

Uncoated lenses don't do anything "weird" to the colors. A little less contrast and a little more flare makes a better looking image in my view.

ic-racer
10-Feb-2016, 18:35
Perhaps you are mistaking coating and chromatic aberration. A coated lens has less flare and a 'color' lens has less chromatic aberration.

Vaughn
10-Feb-2016, 18:43
Perhaps just keeping a good lens hood on the lens might satisfy the desire to coat it.

Jim Graves
10-Feb-2016, 18:50
I'm curious ... where do get a lens professionally cleaned ... is this a normal service of most camera repair shops?

Colin D
10-Feb-2016, 19:07
Ok I found a discussion on this topic on the site from 2004 that seemed to confirm what is being said here, no need to coat the lens unless more contrast or less flare is needed. That satisfies my query, all that is needed now is to get some samples happening.

Thanks

goamules
10-Feb-2016, 19:30
If coatings caused weird things to color film, it would have been a problem for 35mm cameras, which had coated lenses since the 1950s. All lenses were coated post WWII, and there weren't "black and white" and "color" lenses.

richardman
10-Feb-2016, 21:43
I have taken plenty color photos with my old Cooke 7 1/2". It's less contrasty for sure, but works well. Just use it to take photos, don't worry about it. Light has not changed in 100 years :-)

Paddy McKay
10-Feb-2016, 23:48
I also had a lens recoated at Arax years ago: a 270mm G-Claron, but for some reason never ended up shooting with it. See my thread on this forum for more info. It clearly has more contrast now, compared to just a single coating. As many others have pointed out before, for B&W, some people prefer single and/or uncoated lenses for their inherently lower contrast. It helps the shadows to remain a bit more open, and printable. It really all comes down to a personal preference for how one wants to render the image. For colour work, I really love contrasty modern lenses, especially the exquisite Zeiss glass for my Nikon.

Pete Oakley
11-Feb-2016, 03:39
146408Don't know if this is of any use in this thread but I took this with an old uncoated meniscus lens removed from a clapped out Kodak Box Brownie (1920's) and mounted into a Copal Press shutter. This is from a 6x9 roll film back but the lens does cover 4x5.
Pete.

Peter De Smidt
11-Feb-2016, 07:59
The more glass/air surfaces the lens has, the more coating those surfaces will make a difference.

Colin D
11-Feb-2016, 20:13
146408Don't know if this is of any use in this thread but I took this with an old uncoated meniscus lens removed from a clapped out Kodak Box Brownie (1920's) and mounted into a Copal Press shutter. This is from a 6x9 roll film back but the lens does cover 4x5.
Pete.

Thanks Pete, that's a nice sample and gives me some confidence.