Which Hoya circular polarizing filter
I am interested in landscape photography. The 3 questions I have are:
2. Which Hoya circular polarizing filter should I get?
3. Is there any way to gain flexibility if I were to upgrade lenses in the future? i.e. step up ring? Not sure how this works.
Greetings Amaya. There are essentially two answers to your questions. First, why do you think you need a polarizer for landscape work? That along with UV filters are a common misconception. A polarizing filter helps lesson or eliminate glare from some subjects by reducing or eliminating reflections. To enhance colors, you should be using a filter that won't block up shadow details like a color enhancement filter, say redhancer or skylight 81B or even 81C
The second solution to gain flexibility is to get a universal filter system that accepts various lens attachment rings to fit all your lenses, whether 72 mm, larger or smaller than that. Cokin, HiTech, Lee, Sailwind, etc., make these either individually with a hood and a few starter filters, and the rings are sold separately. That way, you don't need to keep buying filters, just new ones for your set and rings are basically a one-shot deal that last forever with proper usage.
With a digital camera and photoshop, you can forget about filters and just shoot and fix although in my view, that's spending a lot of effort to fix what you can pretty much shoot correctly out of the gate.
As far as your lens is concerned, there's nothing wrong with it, but it's a little difficult to hand-hold at slower shutter speeds without inducing camera shake into the photo. My own preference is fixed focus wide angle lenses or shorter focal length zooms, say 17-50 along those lines. With the filter systems I mentioned, you might consider shooting landscapes off a tripod, a monopod, or something that will help you stabilize the camera as you shoot. Even a tree limb works fine.
Take it light ;>)
|Alan N. Marcus||
When it comes to filters: Since we mount them ahead of our lens, we want them to be flat. What I am taking about is Ďoptical flatí. When light transverses a filter, if not flat, both sides, it causes light rays to change their direction. Thus flatness is the first consideration. It is more difficult to make a flat than to make a lens. I have no doubt that all of the Hoya filters have an excellent flatness profile. You can test a filter yourself. Hold the filter parallel to the ground about 10 ~ 14 inches away at chest height. Look at the filterís surface and manipulate it as if it were a mirror. In a room with a grid ceiling, like an office with square ceiling tiles, look at the reflection of the ceiling off the filter. Flip it over so you examine both sizes. If optically flat, the reflected image of straight lines will remain straight, if not flat; the lines will appear wavy. Also, hold the filter at arms length and look through it at telephone lines. Rotate the filter. If flat the lines appear to wiggle, the filter is not flat.
A filter adds another two surfaces to the number of elements that comprise your lens. Some filters, the polarizer is not exempt, are sandwiches, two optical flats encasing a plastic or gelatin sheet. Sandwiched designs have six surfaces. Flatness of each surface is an important consideration.
Each surface is shiny (polished). Each surface reflects away some small percentage of the light. Rays reflected from the front surface are lost. As the rays penetrate refection occurs at each surface junction. Some of these reflections find their way to the focal plane and intermingle with the image forming rays. The net results is they contribute what is called flare. Flare can be devastating as it reduces contrast (snap). That is why one should never mount a filter unless one gains a positive attribute.
Use of the polarizing screen (filter) results in a loss of 2 f/stops in light energy (equable to dividing the ISO by 4). The polarizing screen darkens a blue sky thus it adds saturation causing clouds to appear with more vividness. A polarizing screen works best when the subject is side lighted. You must have the ability to rotate the filter, as you observe. The filters ordination is a major condition of its operation. A polarizing screen mitigates reflections from non-conductive surfaces. It is invaluable when photographing objects behind glass. A polarizing screen reduces haze in distant landscapes. Likely the polarizer is the most valuable filter to own followed by a graduated neutral density filter for dramatic sky darkening.
Some cameras use polarizing filters in their mechanism. These do not image but control light for exposure determination and may be involved in the focusing mechanization. A straight (linier) polarizer can interfere. Thus a circular polarizer is safer. A circular is a sandwich. The first filter is a linier polarizer. It does the job. The now altered (polarized) light is passed to the second filter, it jumbles up the polarized rays mitigating their impact on the in-camera polarizerís.
An optical surface is polished thus it acts like a mirror (ever see your reflection in the window?) To mitigate reflections that cause flare, optical surfaces are coated with a thin layer of fluoride (like teeth treated by a dentist). It is a hard transparent coating. The coating thickness is controlled to be ľ of the wave length of light. When so adjusted it mitigates reflections at that frequency. A multi-coated surface has many such coats. One for each color the optical engineer desires to mitigate. Since blue is the most energetic frequency (itís the shortest) itís the one most often mitigated. Multi-coating handles several other frequencies; it is more costly to make however multi-coating reduces flare best.
Alan Marcus (marginal technical gobbledygook)
Mark & Alan have given you great information.
I dont use my CP for most landscape photos but I always do when shooting waterfalls, rivers and other highly reflective scenes that I want to control the reflection of the water, etc. I have the B&W Kaeseman CP filter and its a bit pricey but one of the best in quality.
I use a tripod & remote shutter release so that I can get as much Depth of Field and use slower shutter speeds to get as much detail as I can. Ansel Adams used to shoot at f/94 so he could hit the shutter and go have lunch while the image was being captured. And as Alan said, you will lose 2 stops with the CP filter. There are also techniques like positioning the camera at about 3 feet to give you a more "classic" landscape look and place the horizon at 1/3 or 2/3 from the top or bottom. I spend more time trying to find an angle that doesn't have high lines in the scene or I have to clone em out with PS later - arggh..
Of your selections I would take #3 with the multicoated glass. Most of my lenses are 77mm so my CP filter works on all the lenses I use for landscape but if that wasn't the case, I would follow Marks suggestion and get a Cokin system. Good Luck, Carlton
Many thanks for such detailed clarifications and suggestions. Will have a look at the various options and go shopping.
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