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SHOP WINDOW -- AUGUST
FILTER FACTS
INTRO
A good quality filter need cost no more
than ten pounds yet it could easily
save you several hundred pounds in repair bills, and it might even improve the
look of your video movies. If you've got a camcorder fit a filter, if you know
what's good for you...
COPY
Filters are amongst the most underestimated
and under-used camcorder accessories. They're the first line of defence for the
camcorder's lens, against dirt, dust and scratches; the cost of a replacement lens assembly and labour
charges can easily run into hundreds of pounds! Filters can do more to change
the quality and appearance of a video movie than almost any other gadget, some
of them can create the kind of special effects that would otherwise be
impossible this side of a fifty-thousand pound computer system.
There are few, if any, technical differences
between the filters originally developed for still cameras, and those now aimed
at the camcorder market, which means -- in theory -- there are several hundred different types available. In practice
only a handful are used in video movie-making, though there's nothing to stop
anyone experimenting with the more exotic ones. There are a number of
mechanical considerations to take into account. The first and most important
one is the diameter of the screw thread on your front of the camcorder's lens
barrel. The seven most common sizes are: 27, 37, 43, 46, 49, 52 and 55mm. 27.
43 and 55mm sizes are less widely used these days, though 27mm is apparently
making a comeback, thanks to Canon's UC series of palmcorders. However, the bottom line is that there are filters
and adaptor rings to fit just about every camcorder ever made.
Older camcorders, with front-focusing lenses,
where the whole lens barrel rotates, may have difficulties with some types of
photographic filter, where the effect
change as the filter turns. Some types of filter can can interfere with the
working of TTL (through the lens) autofocus, white balance, and even exposure
systems though on camcorders with
manual overrides it needn't be a problem.
The three most popular filters for camcorders
are ND (neutral density), Skylight and UV (ultra-violet), they're also the most
useful as they can be left on all the time, to protect the lens. Neutral
density or grey filters are used to reduce the amount of light entering the
lens, to control exposure, and decrease depth of field. These filters are rated by their light
blocking factor, i.e. x2, x4 and x6.
Skylight filters are used to reduce haze and the amount of blue in the
picture. This improves colour balance on brightly-lit outdoor scenes, and gives
the picture a slightly warmer feel; the two strengths reccommended for
camcorder use are 1A and 1B. Ultra violet filters also reduce haze but they
have no significant effect on colour rendition.
Other types of filter worth investigating
are: polarising and special effects filters. Polarising filters are useful
because they can help to eliminate annoying reflections from shiny surfaces
(water, windows etc); it's best to use circular-polarising filters on
camcorders, especially those with rotating front-focus lenses. Of the multitude
of special effects filters the most interesting ones are the classic
cross-screen, which pinpoints spots of light with multi-pointed stars;
diffraction filters, like cross-screen filters but the starbursts are in vivid
colour; multiple-image filters, which create a kaleidoscope effect of repeated
images; and diffuser or soft-focus filters which make all or part of the picture
look misty or fuzzy.
The quality of filters varies somewhat but
it's clear from the prices that you get what you pay for. There's not a lot of point in paying over
the odds for ordinary camcorder filters, the UV, ND and Skylight filters we've
seen are generally well made and adequate for normal machines; owners of
high-band equipment may feels it's worth spending a little extra, though.
Several accessory companies market camcorder filter sets, though according to
some dealers we've spoken to they're not very popular and there are fewer of
them of late; it seems video movie-makers prefer to make their own
selection.
We simply haven't the space to list every
size and type of filter on the market, so here's a brief summary of what's
available, together with representitive prices from a broad selection of the
major accessory companies marketing filters suitable for camcorders:
AICO
High quality
optical glass filters from Japan. Aico cover all of the popular sizes, with the
exception of 43mm, though they do include the very rarely used 58mm size in
their camcorder range. They have UV, skylight, circular polariser, ND (x4) plus 4 and 6-point cross-screen filters in all sizes; 8-point cross screen,
and 3, 5 and 6-face multi-image filters are not available with 27mm threads.
Prices for UV and ND filters start at £5.00, rising to £30 for the more
elaborate effects filters.
AICO
INTERNATIONAL Aico House, Faraday Rd,
London Road Ind Est,
Newbury, Berks
RG13 2AD. Telephone (0635) 49797
CZ SCIENTIFIC INSTRUMENTS
CZ market a wide range of quality Japanese
glass filters both under their own name, and the Regent brand. They have ND and skylight filters to fit most
camcorders (no 43mm ND). Polariser , UV
and effects filters less than 46mm are very thin on the ground, so there's
little to interest palmcorder owners. Prices are generally quite reasonable,
with a 43mm skylight filter costing as little as £3.86, a Regent 46mm circular polariser
sells for just over £15.
CZ SCIENTIFIC INSTRUMENTS PO Box 43, 1 Elstree Way, Borehamwood
Herts WD6 1NH. Telephone 081-953 9456
HAMA
Many of Hama's extensive range of filters
feature 'high-transmission multicoating' or HTMC, which involves four separate
coatings on each side of the glass, to improve image sharpness, contrast and
saturation, as a result they're a wee bit more expensive but that could be
money well spent, especially if you're using high-band equipment. As an example
a 46mm ND filter costs around £9.39, the same size polariser is £18.99.
Incidentally, Hama's filter catalogue is well worth having as it contains
plenty of useful advice, hints and tips.
HAMA Unit 4 Cherrywood, Chineham
Business Park, Basingstoke, Hants RG24
OWF Telephone (0256) 708110.
INTROPHOTO
Introphoto market the well-known Hoya brand
of filters and like Hama many of their products have multiple coatings, to
reduce flare, ghosting and improve colour balance. Their skylight, ND and UV
filters cover all of the most common thread sizes, but their special effects
filters mostly start at 46mm and above. Prices are very reasonable,
consideriong the higher than average
quality. Their 46mm skylight is priced
at £7.17, a ND filter (same size ) sells for £9.87 and a circular polariser
costs £19.62. Another well-produced catalogue, full of useful information
INTROPHOTO Priors Way,
Maidenhead, Berks SL6 2HR.
Telephone (0628) 74411.
JESSOPS
As usual Jessops have all the popular sizes
and types covered, though they've nothing to speak of with a 43mm thread, and
no 27mm ND or UV filters, though there is a skylight 1A and circular polariser.
Prices are very competitive with a 46mm UV filter costing just £3.49, and a
circular polariser for under £10 .
JESSOPS Jessops House, Scudamore Road, Leicester LE3 1TZ
Telephone (0533) 320033
JOHNSONS
Cokin are one of the best known manufacturers
of photographic filters, and now they're making a name for themselves in the
video field. In addition to their very extensive range of individual filters
with 37 and 46mm threads, Cokin have put together a number of kits,
specifically for video applications.
There's two types, the first based on their A-type holder, (originally designed for SLR cameras) there's
twelve kits in total, each containing four filters, geared towards a specific
task or subject. They include portraits, still life, wildlife, architecture,
mountains and snow, and fashion. The
second type comprises threaded filters. Cokin filters can be pricey, but not as
expensive as you might think; for example a 37mm UV filter costs £7. 99, a
camcorder kit containing 46mm UV, ND and polariser filter is actually quite
good value at £27.99.
JOHNSONS PHOTOPIA Johnsons of
Hendon Ltd, Hempstalls Lane, Newcastle,
Staffordshire ST5 OSW. Telephone (0782) 717100
SRB
An unassuming range of filters and kits,
covering most popular thread sizes, though the 43mm selection is a little
sparse. Variable quality but good value, including a kit containing a skylight,
ND, soft spot, starburst and colourburst filters for £16.50. Other examples are
a 46mm ND filter for £3.65, and a circular polariser for £11.30.
SRB FILM SERVICE, 286 Leagrave Road, Luton, Beds LU3 1RB
Telephone (0582) 572471
VANGUARD
Vanguard have UV, skylight and filter kits
for 37, 46, 49 and 52mm thread fittings.
The kits contain UV, polariser and diffuser
filters, plus a 37mm step ring. Prices are
low with their 46mm skylight filter priced at around £3.50, and the three filter
kit (46mm) selling for just under £20.
GUARDFORCE Unit 13 Thame business
Centre, Wenman Road, Thame,
Oxon OX9 3XA. Telephone (0844) 213667
VIVANCO
Vivanco have put together a useful, rather
than extensive range of camcorder filters, concentrating on the most popular
types and sizes, including the elusive 43mm fitting. The range also
features high-performance multi-coated
types, which are aimed primarily at high-band users. Prices are a tad above
average but they're of the highest quality, and very well packaged. A 46mm UV
or skylight starts at £9.99, rising to
£13.99 for the multi-coated versions; a circular polariser will set you back
£27.99, the same sized multi-coated variant is £41.99.
VIVANCO Unit C, ATA House, Boundary
Way, Hemel Hempstead HP2 7SS
Telephone (0442) 231616
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R.Maybury 1993 2505
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