In praise of a polarizer

A while back when considering replacing my lost polarizer, I asked opinions on getting a "warm" one (one that gave a warm tone to the image), and took the advice given that the digital image could easily be "warmed up" if needed when editing on the computer back home.

But as far as increasing saturation, I still feel that a regular polarizer can't be replaced by post-hike editing with photoshop.

I did a little experiment while hiking last week that shows that:


Image without polarizer.


Image with polarizer.

The polarizer knocks out the reflections, which is why it makes skies bluer and leaves greener -- more like we remember the shot. There's no way that just kicking up the saturation while editing later in photoshop can remove a reflection without some serious manipulation.

For ferns, for example, the waxy, shiny surface causes white highlights that are impossible to "green up" in editing, and the stream's reflection of trees and sky, removed with a polarizer, can't really be "removed" later without serious, time-consuming editing.

That 3-oz. filter, I believe, is still one of the most important photo accessories on a hike.

I bought my replacement polarizer on this trip at a one-off, non-chain camera store in Santa Rosa -- one of a vanishing breed.. The owner pulled a box of used filters from under the counter and I searched until a found a scratch-free, brand name one that fit both my lenses (58mm). Cost was a shocking $5. A brand-name new one that size was $65 at that store.

New polarizers, off-brand but almost as good, can be had on-line for $15 or less:

http://www.ciao.com/Quantaray_filter_polarizer_58_mm__10097894

Downside of a polarizer is that it cuts down the light entering the lens, and may require the photographer/hiker to use some form of stabilization when in a dimly lit forest. I used a nearby tree to keep the camera still (and an IS <image stabilization> lens), rather than lugging around a decent-weight tripod.

And finally, that filter -- any filter -- can save your lens in a fall. Years ago, I fell on a hike with camera in hand and the camera took a hard hit on a rock. The filter glass shattered and the outer lip of the polarizer ring was dented. Carefully removing it, I found the lens undamaged.

Three ounces? Does it have a lead mount? <img src="/forums/images/graemlins/tongue.gif" alt="" />

I find pola filters basically a requirement, especially with wide angle lenses. Your water demonstration is a good one; they also cut airborne haze, making for bluer skies and highlighting clouds. They can also enhance colors of certain subjects, such as flowers, by cutting scattered surface reflections.

A caution: Any camera that uses beam splitting for metering or autofocus (most modern digital cameras) needs a "circular" polarizer to work correctly. The less expensive linear polarizer will interfere with these functions in certain situations. Circular polarizers can get expensive, especially when you get into the multi-coated variety, so the suggestion about shopping around is an excellent one. I've gotten a couple used and significant discounts.

Ah the polarizer. Never leave home without one. Wait till you shoot mountains with it, you're skies are going to flip.

Gregp:

Loved those pix on your site.

Nice demonstration, Kevon. Funny....I have a closet full of film camera gear and never left home without polarizer, UV, and star filters. When our house shifted over to digital, I guess I forgot the benefit of filtering light before it made it to the detector plane. None of my old filters fit my newer cameras.

Doesn't that just tick you off? I have bunches of system-wide filters from film gear, almost none of which fit any of my digital stuff (except 67mm). That's a lot of money! I also note that the makers seem to be making less of an effort to have just one or two filter sizes fit most of their lenses. e.g., My Oly digital slr lenses so far take 52, 58, 67 and 72mm.

The now nearly universal requirement for circular polarizers on newer cameras is brutal too. Coated CP filters are at least four times the cost of linears.

Oh well, photography is a better way of ridding oneself of extra cash than Indian casinos, and requires less driving. :-)

I was fortunate when I switched from film to a DSLR in '02. I owned a considerable investment in Nikon glass, so it was a given that I was going to a body with a Nikon mount. I chose the Fuji S2 Pro, which is built in a Nikon body, because it was the only DSLR that could shoot TTL with Underwater strobes. I use all of my old lenses. Some of my older AIS lenses only work in manual exposure but all my later lenses were fully compatible. Even my 12-24Dx lens uses the same 77mm filters as my 28-70 f/2.8 and my 80-200 f/2.8.

I don't use a polarizer for my underwater but I never leave home without it for above water.

Paul & Rick:

One possible solution is using step-up rings if they're larger-diameter original filters (than the filter-thread on your new lens.) Example: say you have a 58mm filter and now you have a 55mm filter thread on the front of your new lens. A simple metal ring, 55mm on the lens side and 58mm on the filter side, does the trick.

Step-down filters sure won't work if on wide-angle lenses because they'll cause "vignetting" (dark edges), but might work if not too radical a size difference on telephoto lenses.

But of course it never seems to work out that way. My observation is that the diameter of the thread mount of newer lenses is getting larger and larger -- or at least for the new lenses I want. (From absorbing your camera knowledge in past posts, Rick, I'm sure you already know about step-up/down rings -- but others may not be aware that there might be a cheap fix.)

A Tiffen 55-58mm (lens-to-filter) step-up ring is $9.95 at B&H Photo online.

A Tiffen 58mm circular polarizer is $20 at B&H for the basic, $66 for the wide-angle polarizer (no front thread on the filter makes it flatter and less chance to vignette), and $80 for the multi-coated one.

So step-up rings not only save money by having to buy fewer filters, but by buying the filter for the widest thread-mount lens, you save weight by not lugging around duplicate filters.

(Rick, can you explain a little more about these expensive multi-coated polarizers? A regular circular polarizer (a non-linear polarizer) won't do? I'm not getting it.)

Hi Kevin,

Good points on step-up rings, they can help trim the filter budget for sure. They're also a good scheme for getting a filter on certain very wide angle lenses w/o vignetting in the corners. My only caveat is they're hard to couple with lens hoods.

I may have misled with the my note on multicoated CP filters. Plain, uncoated CP filters pose no technical problems to autofocus or metering as far as I know. I think I spend too much time on photo lists where folks won't tolerate anything less :-)

That said, if you want a scare, price a couple of Kasemann coated CPs. (For the record I own zero of them, but would like a 72mm someday if I can find a co-signer.)

A B&W Kaesemann multi-coated circular polarizer in the 72-77mm size is about $215. Ouch!!!

I usually mail order such things from Adorama or Focus. There really aren't any good photo shops in Dallas anymore. All my astronomy oculars are mail ordered and filters are usually cheap except for solar or hydrogen alpha.
The sad thing is, I have film cameras ranging from a Mamiya Super Press 23 (2.25x3.25), RB's, Canon F's and A's, two darkroom setups, all pretty much worthless now days. Digital backs can be had for those old cameras but they cost as much as a new SLR. All the lens sizes are different.
My daughter gets instant gratification...and some amazingly good shots...with her 8mp point and shoot digital, which took the wind right out of my photography sails. I bring her if I want first rate photos, now.