info on protect versus uv filters

[qaz]

hi

im trying to find info on protect versus uv filters. i think i know most of the tech stuff after much research, but i cant determine if multi coated protect filters can cause the same problems as some multi coated uv filters. or is the manufacturer of protect filters so straightforward that these problems are not an issue.

at the moment it would seem that for a digital camera i might get better value for money in lens protection by buying a purpose made protect filter, but some advice would be much appreciated

thanks

[Manfred M]

I feel that you are overthinking this.

If you want to use a filter to protect your front lens element; both the "protect" and the UV will be perfectly adequate. Multi-coating (and there are different kinds here; the most important one are the ones that reduce reflections). Protect lenses are clear class and UV ones have a slight yellow tinge (just like the one built over your camera's sensor); optically it makes no difference to the final image quality.

I find that in general, manufacturers are charging a premium for protect filters, so I have tended to go for UV ones. That being said; I have four lenses that have no filters; all were designed without filter threads in front of the front lens element), so I don't use one on any of them.

[DanK]

qaz--welcome to to the forum. Please add your real name and location to your profile. We use real names here, and your location (as you will see) sometimes is important for giving you answers.

I agree with Manfred: UV vs. protective doesn't really matter, but the quality of the filter and coating matters a lot.

I've ended up with the opposite decision: I like Marumi filters (I buy their higher-level 'super') filters, and their protective filters cost less than comparably high quality UV filters. They are harder to find than some other brands, but I buy mine here: http://www.2filter.com/marumi/marumiuvfilters.html. You can check out the review of their CPLs on lenstip.com: right up with the best of the B+W. I don't know if you are in the US; if not, you would have to find what is available to you locally.

[qaz]

yes i take ur point[s] . have studied lenstips reviews, unfortunately im having trouble telling the different features of the different hoya grades [not types] of filters, say, uv filters for instance, there are at least 3 grades.

even the hoya site does not list the "super" for some reason, though i can buy one.

another thing is that annoyingly i cant find anywhere on the web the difference between a purpose made protect and a uv filter [except the obvious of coarse, filtering out UV frequencies], seems this is not thing people need to know cause in some ways its a grey, overlapping area

anyone got ideas?
thanks mark [uk]

[DanK]

another thing is that annoyingly i cant find anywhere on the web the difference between a purpose made protect and a uv filter [except the obvious of coarse]

The UV filters filter out UV frequencies, which is sometimes important for film but is not important for digital. So you can ignore that in choosing filters. In the case of digital, both are used simply to protect the lens, and the issues are identical: you need good multicoating and good glass.

[lukaswerth]

Here is a personal statement:

If I take pictures in back light situations, any filter enhances the danger of ghost images (though with multicoated filters this danger minimized). I therefore try to take proper care of my glass, cover it whenever not in use, and once in a while carefully blow the dust away before, if necessary, gently cleaning the front glass with a moist tissue for glasses. I do this only very occasionally, when there is really some dust on the lens - a lot of dust somewhat reduces the contrast, even though it had to be quite a lot before I am able to notice this in practice - and sometimes it is not even a bad thing to have just that little bit less contrast.

In any case, I think my lenses are in this way more likely to perform as they were designed to.

Lukas

[Manfred M]

Mark - I don't know the Hoya line that well (I have one Hoya filter), but I believe I have covered this off in my initial response:

1. Higher grade will generallybe related to the quality of the coatings; one other difference you might find is that if you are shooting with a wide-angle lens, you might want to consider getting a "slim line" filter; which reduces the risk of vignetting at wider angles and you might be paying extra for that.

2. We've already told you the difference between a plain filter and UV; what part of that did you not understand?

3. If you are looking on eBay to buy filters, there are cheap counterfeits out there. I would assume that if the Hoya site does not list it, it is a fake and I would not buy it.

[William W]

im trying to find info on protect versus uv filters. . .
i think i know most of the tech stuff after much research, but i cant determine if multi coated protect filters can cause the same problems as some multi coated uv filters. or is the manufacturer of protect filters so straightforward that these problems are not an issue. . .

You will have the same issues with a Protect Filter as a UV Filter, all other aspects of the Filter’s quality and coatings being the same. I remove the UV Filters that I use for ‘lens protection’, when I am in a shooting situation that requires their removal.

*

im having trouble telling the different features of the different hoya grades [not types] of filters, say, uv filters for instance, there are at least 3 grades. . . even the hoya site does not list the "super" for some reason, though i can buy one.

Hoya do make a filter labelled “SUPER”. It is the SMC Series (Super Multi Coated), the rim will have ‘SMC SUPER’ printed on it. The SMC is their ‘General Filter Series’; and I think that there is only UV and not a Protector Filter in this series. It would be strange if this is series of filters were not listed on the Hoya website.

‘PRO 1’ is a more expensive series and in this series you can get both UV and PROTECT Filters.

‘HD’ is the next and the most expensive series of filters from HOYA and you can also get UV and PROTECT in this series. One aspect of these filters is the very strong hardened glass which is used.

*

another thing is that annoyingly i cant find anywhere on the web the difference between a purpose made protect and a uv filter

The difference between UV and Protect is simply that (good quality) Protect Filters are have (almost) ZERO attenuation of ANY PART OF the spectrum – whereas (good quality) UV filters attenuate the UV portion of the spectrum.

Most Film Emulsions are sensitive to the UV spectrum but Digital Sensors are not so sensitive (practically insensitive) to UV.

I carry a UV Filter on the end all my lenses as ‘protection’. I use mainly PRO 1 UV Filters and some HD series on the lenses that are used on my digital cameras. I don’t believe that a ‘Protect Filter’ will benefit me any more than a UV Filter when using a Digital System. I have mostly PRO 1Series UV Filters, because I bought them before the HD Series was introduced, but now I buy HD Series Filters.

WW

[GrahamS]

There are a number of things to bear in mind when considering the difference in quality of various types and brands of filters, that are sometimes taken for granted. These are:

The filter ring - some are made from soft aluminum which tends to distort and bind easily, some from good quality brass, which retains it's shape better and has better thermal stability and some from stainless steel, which is the most expensive and has good resistance to distortion and thread damage. The aluminum type can be painted or anodized black, the brass can be painted or plated and the stainless steel is usually polished or bead blasted to a satin finish.

The coating - some filters are not coated at all, some are coated with a simple anti-reflective coating on one surface, some have a multi-layer anti-reflective coating on one surface and some have multiple coatings on both surfaces. Some incorporate the primary filter material within the glass itself, some apply it as a coating. The quality, technology and efficacy of the coatings can vary greatly.

The type of glass - some are made with what I am sure is window glass, some from optical glass and some from tempered schott glass and some from super thin optical glass as used for the manufacture of lens elements.

All of these factors have a bearing on the final cost of the filter. There are also counterfeit branded filters out there. Tiffen were one brand to suffer from counterfeits ruining their reputation, and counterfeit Hoya filters are also around. I don't buy my filters on e-Bay. I only purchase over the counter from a reputable dealer whose suppliers are reliable.

It pays to buy the best that you can afford. A cheap filter won't do your expensive lenses any favours.

[Manfred M]

The filter ring - some are made from soft aluminum which tends to distort and bind easily, some from good quality brass, which retains it's shape better and has better thermal stability and some from stainless steel, which is the most expensive and has good resistance to distortion and thread damage. The aluminum type can be painted or anodized black, the brass can be painted or plated and the stainless steel is usually polished or bead blasted to a satin finish. .

The problem is not actually the aluminum, but rather aluminum oxide. Aluminum is a very reactive metal and the oxide forms quite quickly upon exposure to the oxygen in the air, and tends to bit a bit rough and uneven. Aluminum oxide is a very hard material and is used as an industrial abrasive, for instance grinding wheels. The paint on the aluminum ring will act as a bit of a buffer between the filter and the lens mount, but as the paint wears, you will actually be scraping an abrasive against the filter mount threads of your lens. No wonder it binds.

That being said, aluminum is soft, light weight and relatively inexpensive, which is why it has replaced traditional brass in optical components, including lenses. Brass is a somewhat self-lubricating, malleable and corrosion resistance material as well. It is used in higher end filters from high end filter manufacturers, for instance B+W and Heliopan.

Stainless steel (more properly know as corrosion resistant steel), is a relatively hard and difficult to machine. Using it really is a marketing gimmick, in my opinion and have never seen a filter made of this material. Including a highly reflective metal in an optical element defies logic…

The coating - some filters are not coated at all, some are coated with a simple anti-reflective coating on one surface, some have a multi-layer anti-reflective coating on one surface and some have multiple coatings on both surfaces. Some incorporate the primary filter material within the glass itself, some apply it as a coating. The quality, technology and efficacy of the coatings can vary greatly.

Anti-reflective coatings are applied using a vacuum deposition process, where the anti-reflective material (usually a metal) is evaporated in a vacuum chamber and allowed to condense on the glass surfaces. These tend to be quite tough. Multiple applications provide improved anti-reflective coatings. More modern techniques apply nano particles in the production process and there are some processes that are under development (I’ve seen papers from both Canon and Nikon) where patterns are etched into the glass elements. I’m not sure if these are used in production yet, and if so, they are more likely to be used on lens elements than filter blanks.

Filters themselves come in two main production methods; mass dying where the colourant is mixed in with the glass material and is cast with the material evenly distributed throughout the material. This is a more expensive process used in higher end filters. Lower end filters (I believe Tiffen does this on all their lines) a thin sheet of coloured resin is sandwiched between two glass surfaces. This is much cheaper to produce, but introduces four additional optical surfaces where reflections can occur. All polarizers are produced this way and all grads also are used dyed resins.

The type of glass - some are made with what I am sure is window glass, some from optical glass and some from tempered schott glass and some from super thin optical glass as used for the manufacture of lens elements.

Schott is a glass maker that is owned by the Carl Zeiss company. Hoya, who are the world’s largest producer of optical glass are unlikely to use anything other than their own product in their filters.

Common “window” glass is unsuitable for optical use as it has a natural green tinge. I'm sure that this will be found in a lot of cheap knock off filters.

[qaz]

getting no notification of new posts.

anyway i should thank people for all [most] of the input, especially the very interesting/useful highly technical posts. have chatted with the uk importers to clarify a few more things and decided on the hoya pro 1 d super hmc uv filter . gawd they get expensive as the get wider [yes i know its harder to make glass flat]
mark

[William W]

getting no notification of new posts.

If one subscribes to a thread at CiC an alert is sent if there is a response to that thread and then no more are sent until you visit.

Also you will only receive the text of the original reply and not any additional edits as in this post.

WW

[shreds]

gawd they get expensive as the get wider [yes i know its harder to make glass flat]

mark

Like most things in photography, quality costs!

Having said that, quality components usually do their job very well and outlast the cheaper inferior ones. Look at the cost of Colin's recommended Singh Ray filters!

[Brev00]

My advice is always to buy a nice filter wallet that will hold your largest filter and a few more filters and filter-related items (step-down rings, for instance). Even if one keeps a filter on one's lens all the time, there are going to be times one changes to a polarizer or some other type of filter. Plus, it is possible you will start to remove your filter in certain situations (i.e, scenes with bright, artificial lighting). You will want a safe place to put that nice filter. Then, you might find yourself rarely putting it back on (crowd scenes, beach trips, etc.) so you will know where it is when you need it.