Wratten Gel, Acrylic, or Glass Filters?

[neil poulsen]

Ansel Adams preferred using Wratten gel filters by Kodak. He stated in his earlier Camera book that they have very little optical affect (aside from their color influence), but that they can be a bit reflective.

I would suspect that the best filters are B&W multi-coated glass filters, as they would be the least reflective and transmit the most light. But for non-reflective situations, I'm wondering how the Wratten gel filters would compare?

And, how would Wratten gels perform compared to "B" quality filters made by Tiffen, etc?

In terms of their optical quality, acrylic filters, like those made by Lee, etc., are a mystery to me. How do they compare to either gel or glass filters?

Your insights would be appreciated. I have a ton of filters, and I'm interested in paring them down to the few that I need for black and white film.

[Mark Woods]

Hello Neil,

I've used the filters for lighting in front of the camera. I know the Great American Market filters are of optical quality. I've used others too with no problem.

[Kevin Crisp]

I used to use the acrylic ones, mounting them behind the lens. I could see no better or worse performance than high quality B+W ones mounted in the front. They are lighter and more compact. And require careful handling. People do look down on the lowly Tiffen filters but I've never had a problem with those either so long as I am not shooting into the sun.

Fred Picker had a line somewhere, newsletter or somewhere else, and if I may paraphrase: 'After you expose with a filter, take a second negative without it so you have one to print.' There is some truth to that.

[Kirk Gittings]

I used to follow the AA approach till I joined this forum. It was a long time ago but I seem to remember someone (maybe Sandy) showing some data that the best glass filters had better transmission than gelatin. Maybe someone else knows where this data is at and can share it.

[Kirk Gittings]

Fred Picker had a line somewhere, newsletter or somewhere else, and if I may paraphrase: 'After you expose with a filter, take a second negative without it so you have one to print.' There is some truth to that.

What does that mean?

[Kevin Crisp]

I took it to mean that he thought that many times he looked at his filtered negatives and concluded "oh, wish I hadn't done that."

[LabRat]

Gels are nice as they are so thin, that they don't refract as thicker glass filters, but they are fragile to dust/moisture/handling, and can blow away in the wind!!! Better in the studio...

The plastic filters are pretty good now, but require a holder that is larger and some care is still required to handle and store...

Glass filters refract more, so they need to attach to the front threads with zero error, and can be an issue with UWA lenses... But the toughest, and most compact filter...

One warning about the MC glass filters:

These filters tend to fog over more easily during exposure to high humidity from moisture, and are nearly impossible to clear the fog while out in the field, until they dry out in a dryer atmosphere...

I'm fine with glass...

Steve K

[BrianShaw]

What does that mean?

Picker was too picky. I respected the guy but found him to be a bit of a bore.

[BrianShaw]

I find any filter to work okay as long as accompanied by an effective lens hood. But maybe I'm not discriminating enough.

My preference though is for gel or glass.

[Drew Wiley]

Well, Ansel Adams also smoked and preferred steak for breakfast, and drove a gashog vehicle back when gasoline was around a dime a gallon. I use true Wratten filters in the lab sometimes, due to the huge selection of special types once available. But their are expensive, fragile, and do in fact slightly degrade image quality if you're speaking about fully modern lens usage. Ansel's lenses weren't anything like today's. Polyester filters like Lee sells affordably will consipuously degrade image quality. Cast acrylic filters won't, but again are fragile, expensive, and prone to reflections. Sandwich-style Tiffen filters are so-so. They attract condensation easily; but they do have a big selection. I personally buy only high-quality multicoated glass filters. You don't generally need very many of them
if you understand what you are doing. You will pay somewhat more for those in brass mounts, which are less likely to bind threads than aluminum mounts. But
optically, multicoated Hoya filters are superb at a reasonable price. Or even single-coated glass filters can be obtained for a relative bargain, and work just fine
if you shade your lenses. Labrat has everything backwards. Any decent glass filter produces no refraction. They're plano-parallel. And they are FAR more resistant to moisture than plain surfaces. I shoot in the mountains and along the shoreline all the time. Five out of the last six vacations I used view camera in blizzards, sleet, rain, hail, and hell at high altitude. And here at home it's foggy most of the year. Only multicoated glass will do for me outside the lab, and even there I prefer MC glass whenever a given type is available.

[Kirk Gittings]

I took it to mean that he thought that many times he looked at his filtered negatives and concluded "oh, wish I hadn't done that."

That's why I tend to under filter a touch and make up for it by burning and dodging a hair more-hard to undo when you over filter.

[LabRat]

Well, Ansel Adams also smoked and preferred steak for breakfast, and drove a gashog vehicle back when gasoline was around a dime a gallon. I use true Wratten filters in the lab sometimes, due to the huge selection of special types once available. But their are expensive, fragile, and do in fact slightly degrade image quality if you're speaking about fully modern lens usage. Ansel's lenses weren't anything like today's. Polyester filters like Lee sells affordably will consipuously degrade image quality. Cast acrylic filters won't, but again are fragile, expensive, and prone to reflections. Sandwich-style Tiffen filters are so-so. They attract condensation easily; but they do have a big selection. I personally buy only high-quality multicoated glass filters. You don't generally need very many of them
if you understand what you are doing. You will pay somewhat more for those in brass mounts, which are less likely to bind threads than aluminum mounts. But
optically, multicoated Hoya filters are superb at a reasonable price. Or even single-coated glass filters can be obtained for a relative bargain, and work just fine
if you shade your lenses. Labrat has everything backwards. Any decent glass filter produces no refraction. They're plano-parallel. And they are FAR more resistant to moisture than plain surfaces. I shoot in the mountains and along the shoreline all the time. Five out of the last six vacations I used view camera in blizzards, sleet, rain, hail, and hell at high altitude. And here at home it's foggy most of the year. Only multicoated glass will do for me outside the lab, and even there I prefer MC glass whenever a given type is available.

Drew, let me explain...

I had been in west Florida during Hurricane Katrina, where the hurricane didn't hit, but was having record humidity and heat then... My perfectly clean MC filters when taken from the cooler indoors/car AC to the outside would suddenly dew over, and wiping them didn't help until they were returned inside for awhile... The uncoated filters could be at least wiped down and used, but not the MC's... A good test would be if you breathed on the clean filter, and how long would it take for your fog to clear... (MC's take longer...)

Yes, glass filters refract a little... Tilt/flick them off axis in your hand while looking through them, and you can see the image shift around...

And try using a thick glass filter on a UWA lens, and look at what happens toward the edges of the image on your film...

But whatever works for you...

Steve K

[Kevin Crisp]

The MC Hoya filters are nice and well priced relatively speaking.

[Mark Woods]

I used to own 160 Tiffen filters, 2/3's were 6.6"x6.6" and I used a lot of them on every scene I shot. The most number of filters I used on a shot was 9. If one is careful and understands how to meter the scene and how the filters affect the image, you won't have a problem. The key part of this statement is if one "understands how to meter the scene and how the filters affect the image."

[neil poulsen]

The one I thought I was including as "acrylic" filters, were "resin" filters.

To the question, how do resin filters compare with the others: glass (MC, SC), gels, and acrylic filters?

[Peter Gomena]

I gave up on gel filters for use in the field several years ago. (I shoot on the Oregon coast. It rains, drizzles, pours, and the wind blows a lot.) They are too fragile and expensive. I switched to a small set of Tiffen glass filters in 77mm and a few adapter rings so I could use them on my various lenses. I use them with a Lee lens shade. No complaints here. I'd buy the fancy ones if I could afford them.

[Wayne]

Glass, preferably B+W but I also have Hoya and Tiffen. All were bought used and I never paid more than $20 for one. I rarely use any filters except for color.

[MartinP]

Referring to the comment above about using filters behind the lens, inside the camera, is there any downside to this (apart from removing the lensboard a little more frequently)? It sounds 'obvious' that the inside of the camera will be the best possible sun-hood, so why doesn't everyone do this?

I noticed a film clip of Clyde Butcher placing a gel behind the lens and it made me wonder why I was fiddling around with adapter rings.

[Kirk Gittings]

Referring to the comment above about using filters behind the lens, inside the camera, is there any downside to this (apart from removing the lensboard a little more frequently)? It sounds 'obvious' that the inside of the camera will be the best possible sun-hood, so why doesn't everyone do this?

I noticed a film clip of Clyde Butcher placing a gel behind the lens and it made me wonder why I was fiddling around with adapter rings.

I did this for years on lenses where I could do this from the front. 4x5 field cameras that use Linhof boards are a bit tight from the front and I found it a PITA to do it by removing the back. I got away from it because I often times work in rapidly changing light and after making one negative will remove the filter and check or change settings etc. It was just too slow in rapidly changing light and I find a consistent routine helps me avoid mistakes. These days I am happy with a decent lens hood or using my dark slide.

[Drew Wiley]

Putting filters behind a lens is always a bad idea unless the lens was specially engineered for this application. It will degrade the sharpness of your image. I have
no idea why Clyde Butcher would do this except for the fact he well might have been using a monster-sized lens, and simply didn't have a filter big enough for the front element. Otherwise, some utterly ridiculous statements have popped up since I last posted. The more air/glass interfaces you interpose between the world and your film, the more risk of image degredation. That applies to attached filters as well. And what LabRat perceived as refraction on his multicoated filters was more likely the interaction between the respective layers of coatings. Otherwise, coatings create a smoother surface with less affinity for moisture than uncoated, though I strongly prefer hard coating to soft. Think cloud seeding. Dirt particulates or flaws on the surface, even when too small to see, attract
droplet formation as well as vapor contaminants.

[Kirk Gittings]

I first heard about this from Fred Picker in his newsletter I believe. It worked just fine but was a PITA as I said above.

[MartinP]

Thanks for the speedy responses! I think making myself a super-effective lens-hood will be the way to go, unless it is both sunny and windy - which is certainly possible here, together with hail and rain, sighhhhh.

Edit: Here (https://www.youtube.com/watch?v=PM19W5m5dQg) is the clip that sparked off the idea, at about two minutes Mr.Butcher mentions filters. My 4x5" camera is a baseboard design, made from foamboard and spruce strips, currently being fiddled with to make a sprung-back instead of using rubber-bands. It should be possible to add to the front box section to make a significant lens-hood and filter-holder (or find the right thread-adapter).

[Drew Wiley]

I sure hope you didn't believe everything Fred Picker said, Kirk. For one thing, every single lens maker and reputable filter manufacturer discourages rear filters for valid optical reasons. Second, do a side by side test, front versus rear filter application, then check the results with a loupe or serious enlargement. It becomes pretty apparent why. A few huge telephotos as well as process lenses were designed for internal filter insertion, near the nodal point. Otherwise, it's always in front.

[Jerry Bodine]

Apparently Sinar has no problem with using filters behind the lens. They offer a filter holder #547.41 that is attached to their Behind-The-Lens shutter and holds up to three 100mm (4") filters - presumably gels.

[IanG]

I think it's something you have to try for yourself. I've used Glass filters, gels, acrylic filters etc, over the years and been critically happy with them all. The tests I've seen references to are how effective different UV filters are which quite frankly is gear porn.

Given a choice logic is a good glass filter is the best but with various LF lenses with various filter threads that's not very practical, I;ve used Cokin & laterLee filters for years, I think since Cokin were first available in the UK about 40 years ago. I've never had an issue even with 35mm where nany problem would be far more apparent, I've also never heard of a single image quality issue. I have heard of slight colour shifts with ND filters but then I've seen the same posted here for high end glass ND Center filters.

The reality is if you look at some of the people using Cokin & Lee acrylic/resin filters they are known for the exceptionally high quality of their LF (now mostly likely digital) colour images.

As Dan Fromm says about lenses, ask it yourself, try it, see what it does and the same goes for filters.

Ian

[Drew Wiley]

Of course, everyone has a right to learn the hard way. It's just time and money.

[Kirk Gittings]

I sure hope you didn't believe everything Fred Picker said, Kirk.
What a laugh. If I did I'd still be doing it! Of course I don't believe everything anyone says. If I used to, listening to you would certainly have cured me of that pretty quick!

Here is what QT says:

"Attaching filters at the rear of the lens

With LF, you have the option to attach filters at the rear of the lens. This works for color correction filters which don't need to be adjusted. The advantage is that a filter inside the camera is less likely to get dust, dirt, smudges, fingerprints, and will cause less flare.
There are two precautions to take:

You have to be super careful to keep your filter clean. Any dust, dirt, smudges, fingerprints, as well as defects, will have more of a detrimental effect on the quality of the image as the light passing through the imperfections has already passed through the lens.
A filter mounted behind the lens creates a focus shift equal to 1/3rd the thickness of the filter so all focusing must be done with the filter in place, except for gels, whose thickness is neglectible."

[eli]

Kodak made small, thin metal frames for the Wratten filters and I simply leave them on the filters, kept in their envelopes, which makes them easier to handle and less likely to blow away.
If you like, you can also cut these filters to size for using with series filter holders, push on and threaded.
You also might consider giving the Series glass filters a try as well. There were a lot of good makers of the filters and I don't see a lot of folks using them, meaning you likely won't have to spend a bundle on them, when you find them.

[IanG]

Of course, everyone has a right to learn the hard way. It's just time and money.

What planet are you on ? There's nothing hard to learn, you need a reality check.

In practice we sometimes have to use gel filters, in theory these should be the worst option compared to resin/acrylic and then glass, but they don't affect image quality used carefully in fact they are usually used to improve it.

In 50+ years of shooting film I've never had an image degraded or losing any quality because a filter of any type gel, acrylic/resin or glass has been used.

Ian