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Ken Grooms
4-Dec-2006, 22:20
Do you guys use polarizers for color landscapes in direct sun?

Also, my 35mm lenses are threaded, but my Rodenstock isn't. Do I get a non-threaded filter?

Thanks.

Andrew O'Neill
4-Dec-2006, 22:37
Really? There is no thread?

Frank Petronio
4-Dec-2006, 22:43
Which lens did you get again? Every 210mm Rodenstock Sironar I've ever seen has 67mm threads inside the rim of the front element, just like a 35mm lens.

Capocheny
4-Dec-2006, 23:23
Ken,

What Rodenstock lens do you have?

It might be useful for you to look for your lens on the Rodenstock website at:

http://www.linos.com/pages/home/shop-optik/rodenstock-foto-objektive/

Strange!

Cheers

Eric Leppanen
5-Dec-2006, 00:11
Ken,

To answer your first question: if your objective is to darken the sky, polarizers have their strongest effect at a ninety-degree angle from the sun; they have no effect looking directly at or away from the sun. So there is no point to pointing a polarizer directly at the sun unless you have an unusual situation where you want to eliminate reflections (say on a window or body of water within the composition). In fact, a polarizer pointed directly at the sun can degrade your image by exacerbating lens flare (especially if the polarizer is not multi-coated).

Robert Oliver
5-Dec-2006, 00:19
I use a polarizer in very rare situations only when using color film.

For black and white film I tend more towards colored filters (ie... red, green, yellow filters) depending on what effect I am going for.

Emrehan Zeybekoglu
5-Dec-2006, 00:31
Ken,
I agree with Eric. Polarizers are most effective when you use them with an angle. When used in the direction of the sun's rays, I find no effect at all.

Secondly, as a side point, I find myself using fewer filters in 4x5 than in 35mm. Most of the time I find the color rendition and the contrast of my lenses pleasing in LF, so with the exception of a few basic filters I've made no investment in those things for my 4x5 camera.

My best..

Ken Grooms
5-Dec-2006, 05:40
Sorry - I found the threads.:o

Perhaps I'll try it without using a polarizer, however, since that seems the conventional wisdom around here.

BTW, I meant to say sunlight, not direct sunlight. I've used polarizers before, so I'm used to angle needed for maximum effect.

Brian Ellis
5-Dec-2006, 08:20
The problem with polarizers, especially when using wide angle lenses, is the vignetting that tends to occur in broad expanses of a single tone such as the sky. So when I printed in a darkroom I seldom used them to darken the sky, my main use was to reduce reflections. But with digital printing and Photoshop it's easy to eliminate the vignetting in the print so I've used them more in the last few years than I used to.

With b&w film I prefer to use a polarizer to darken sky rather than an orange or red filter because they usually have less effect on other things in the scene, especially green foliage. As you know, a red filter often will turn green foliage almost totally black which seldom is desirable. In fact the polarizer sometimes helps improve separation in green foliage by removing reflections. Also, with a polarizer I can predict the degree of effect the filter will have. With orange or red filters and b&w film you're pretty much guessing. But either will work in the right situation, it's mostly a matter of what you're used to and comfortable with.

Jim Jones
5-Dec-2006, 08:22
Long ago most lenses weren't threaded for filters. We used slip-on filter holders. They came in a series of several sizes. Some old camera stores may have boxes of these somewhere. Your lens will likely use the larger and somewhat scarce filters and holders. Once you have the right slip-on filter holder, it can accept threaded filters via an adptor. You might also find the filters that fit the slip-on holders, although old ones won't be multicoated, and likely not even coated.

roteague
5-Dec-2006, 10:35
I use a polarizer quite frequenly - mostly a warming type.

naturephoto1
5-Dec-2006, 10:44
I use a polarizer quite frequenly - mostly a warming type.

As does Robert, I use a Polarizing filter quite frequently with my transparencies. In fact my most used filters for transparencies are Grad ND filters, Polarizing filters, or warming filters for transparencies. Like Robert, I use mostly the warming variety almost retiring my regular polarizing filters for transparencies. My latest one being the new Singh Ray Lighter Brigter Warm Polarizing filter. This filter is available in many sizes including to fit the Cokin P round filter size (which I use); additionally, this filter has less light loss than the normal filter (has more light transmission).

Rich

Rory_5244
5-Dec-2006, 10:54
Er. I'm kinda embarrassed to admit, but I use a rather cheap Cokin polarizer. So ladies and gents, I don't quite understand the huge price differences between the 'lesser' and 'better' brand polarizers. Is it all in the quality of the materials used (I presume we all use linear polarizers here)? Or will a Singh-Ray filter make my chromes look better than my Cokin?

naturephoto1
5-Dec-2006, 11:08
Hi Rory,

Singh Ray uses some very expensive glass in their filter. It is also circular (that does not appear to be mentioned on their website- but marked on the case and filter), includes both the polarizing and warming filters in one, and is 66% faster than filters of other makers (only loses 1 1/3 stop to the exposure). In general Singh Ray filters are known (particularly Grad and Gad ND) filters as being very neutral. And yes, I would not be surprised if the chromes would look better with a Singh Ray or other top grade maker of filters than those taken with the Cokin. This may become more evident as you print larger however.

Rich

Rory_5244
5-Dec-2006, 11:56
Thanks Rich. <Sigh> The good stuff is always so expensive.

naturephoto1
5-Dec-2006, 12:08
Thanks Rich. <Sigh> The good stuff is always so expensive.

Hi Rory,

Shooting 8 X 10 chromes is expensive too. :eek: ;)

Robert and I shoot preloaded Quikloads (or Readyloads) for our 4 X 5 for transporting lighter weight. I comes with the territory. :(

But, if you get the Singh Ray in the Cokin P size it fits into the slot of the Cokin P Holder for Polarizers and can use the same filter on lenses with filter sizes (with the proper adapters or several) of 40.5 to 82mm. Also, if you purchase the Singh Ray filter, you will only lose 1 1/3 stop which allows easier focusing on the GG and higher shutter speeds for the same aperture. :D

Rich

Greg Miller
5-Dec-2006, 12:46
A polarizer is useful in sun or on overcast days (or anytime foliage is wet) for reducing glare on foliage. So anytime my scene includes foliage I will consider using a polarizer. Before putting the filter on the lens I will look through the filter and rotate it to get a feel for what, if any, effect it will have and where the best point is. Then I'll screw the filter onto the lens and orient the filter to the same position. It helps to have a filter, like a B&W, that has markings on the filter rim to help ensure the poliarizer is oriented the way I want.

Don't forget to adjust your exposure to compensate for the loss of light reaching your film.

Bob Salomon
6-Dec-2006, 07:10
"The problem with polarizers, especially when using wide angle lenses, is the vignetting that tends to occur in broad expanses of a single tone such as the sky."

Brian, that isn't vignetting. When photographing large expanses of sky with a polarizer you will get dark bands frequently as some parts of the sky are naturally polarized and others are not. Those that are appear darker.

Rory, Polarizers vary in price because of several factors:

1: quality of the polarizing foil used. There are several grades that can be used for camera optics. The cheaper filters use polarizing materials that are not as color neutral, that are not as thin, not as flat, etc.
2: quality of the glass. From very high quality glass that is ground and polished to less flat float glass. The flatter the glass the less likely a filter will effect the sharpness.
3: type of construction. Most polarizers consist of 2 pieces of glass laminated to a polarizing foil (linear types, or two pieces laminated to a polarizing foil and a quarter wave plate - circular types). Kaesmann type polarizers are especially high quality foils in very high quality glass. The foils is stretched flat and held under tension in the glass which is then edge sealed to make it fungus and moisture proof.
4: quality of the mount. Cheapest versions use aluminum or plastic mounts which can bind or cross thread easily on a lens. Best types use solid brass mounts. The very best ones have calibrated mounts to let you preview the effect of the filter at your eye and transfer that position to the filter when it is on the lens.
5: coatings, multicoated with dust and moisture repelling top coat on both sides of the filter. multi coated without dust and moisture repelling coaating, multicoated one side only, not multi coated. Light transmission of the coatings. The very best multicoatings pass over 99.9% of the light to the image plane. The very worst pass less. That means that the very best have better contrast and color with no hazing due to reflections from light that was reflected off the front or rear of the filter.
6: hard coatings that are easy to clean - like those on a lens or soft coatings that are very difficult to clean and look like a smear on the lens.

You get what you pay for.

Daniel Geiger
6-Dec-2006, 08:59
I regularly use pols for chromes: Darken sky, make clouds pop, get better foilage even in dry condition. I think, pols work on foilage in dry condition because of the wax cuticula on the leaves. It is particularly noticeable on xeromorphic plants such as chaparral oaks.

Circ vs. linear polarizer only matter if you have half reflective mirrors or some sensitive AF mechanism. For LF it does not matter. If you shoot several formats including 35/MF, then a circ pol can also used on those systems, and will not interfere with your LF work (my approach).

Rory_5244
6-Dec-2006, 09:16
Thanks a lot for that sobering thesis, Bob. Looks like I may be hunting for a better polarizer soon. :(

naturephoto1
6-Dec-2006, 09:50
Thanks a lot for that sobering thesis, Bob. Looks like I may be hunting for a better polarizer soon. :(

Hi Rory,

As some of us have mentioned, if you use other formats that require a circular Polarizing Filter, consider getting one. Use generally the largest size filter that fits your lenses (or most) and then get step up rings (avoid step down rings) to fit the larger filter on the smaller thread sizes of the lenses. You had mentioned the Cokin P size filters. If that is what you are using the Filter Holder accepts filter sizes up to 82mm. If you consider getting a Warm Polarizing Filter for your chromes, you may wish to consider the Singh-Ray Lighter Brighter Warm Polarizing Filter in the Cokin P Size. As I mentioned this fits the Cokin P slot for Polarizing filters, is neutral but warm (includes warming filter), is very high quality, only loses 1 1/3 stop of light, and is a circular type.

Here is a link to the Singh-Ray:

http://www.singh-ray.com/polarizers.html

Good luck with the search.

Rich

Rory_5244
6-Dec-2006, 10:34
Thanks Rich! You're a treasure. I'll be getting the polarizer in the Cokin P mount. Thanks again.

roteague
6-Dec-2006, 10:51
You get what you pay for.

Thanks Bob, great review here. I personally use B&W filters, I've often thought about the Kaesmann filters, wondering if they really were worth the extra costs.

brian reed
6-Dec-2006, 16:26
If its one filter I would recommend, it would be a polarizer. I use a circular b&w warming filter mostly, because I use it with my 35mm and use step up rings for my LF lenses. I use it not only for darkening the sky but for removing reflections on foliage and any glare on some wet rocks perhaps

BR

www.brianreedphotography.com

Jim Ewins
6-Dec-2006, 16:30
Lee makes a holder for gelatins and cokin filters it is held on with rubber bands.