Using compact flourescent lamps for lighting

Discussion in '35mm Cameras' started by Peter Chant, Nov 18, 2004.

  1. Peter Chant

    Peter Chant Guest

    I've noticed a picture of some studio lighting using compact flourescent
    lamps. I've seen US websites selling lamps stating they are ideal for
    digital photography. I'vealso seen 6500K daylight balanced lamps
    advertised in the UK, but no comment on photography.

    Are any of these any use with film?

    Pete
     
    Peter Chant, Nov 18, 2004
    #1
    1. Advertisements

  2. Peter Chant

    Bill Tuthill Guest

    Yes. The daylight-balanced CF bulbs work well with regular print film
    and even with slide film. Perhaps they don't work quite as well as
    the expensive photography-ready continuous-spectrum fluorescent bulbs,
    but they certainly are a lot cheaper!

    The "soft white" CF bulbs appear somewhat yellow, as you would expect,
    but not ugly green like old-style long-bulb fluorescents.
     
    Bill Tuthill, Nov 19, 2004
    #2
    1. Advertisements

  3. For the most part all fluorescent lamps are problems for really good
    color. Not just for film or digital, but also for your own eyes. That is
    why most meat displays in markets don't use them. However they are getting
    better and the best ones are not too bad. Film and digital will react
    somewhat different, but not necessary better or worse.

    I suggest you give the ones of your choice a try and see if it works for
    what you want.
     
    Joseph Meehan, Nov 19, 2004
    #3
  4. Peter Chant

    Alan Browne Guest


    It is becoming a serious lighting option for small _digital_ studios. Much
    easier to work with than strobes, can be ganged up cheaply (I saw one product
    with 9 flourescents in a gang behind a softbox...). As they are somewhat cooler
    than incandescent you don't get nearly as much heat. The color temp is well up
    into the fabled daylight range ...but even if not, most digital cameras have a
    color temp setting.

    Another lighting option is bright LED's which come in at over 5500K and are also
    ganged up... probably great for a variety of situations ... (no idea on cost,
    etc.) http://www.led-shop24.de/assets/own/5mm_white.pdf and can be ganged up
    into standard socket fixtures. (Can't find the link right now).

    The big caveat with all the above is that even with a lot of lighting you'll be
    working with fairly slow shutter speeds which might not meet some needs.

    Cheers,
    Alan.



    --
    -- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
    -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
    -- [SI gallery]: http://www.pbase.com/shootin
    -- [SI rulz]: http://www.aliasimages.com/si/rulz.html
    -- e-meil: there's no such thing as a FreeLunch.
     
    Alan Browne, Nov 19, 2004
    #4
  5. Peter Chant

    Bandicoot Guest

    [SNIP]

    Yes but...

    They aren't a continuous spectrum source (even Kino-Flo aren't), unlike
    Tungsten, flash, or, of course, daylight. Thus they don't, in the true
    sense, even have a colour temperature: rather they produce an 'overall
    effect' that is equivalent to a given colour temperature by having a series
    of emission lines that mix to produce a good approximation of 'daylight
    white'. This would be fine, except that both colour film and digital
    sensors don't have a continuous response either: they have dye layers, or
    sensor sites, sensitive to different 'colours' and the mixing gives us the
    end result - this means that you can get interaction between the spikes in
    the emission of the lamps and the colour sensitivities of the film/sensor.

    Overall, this means that good fluorescent sources can be used effectively
    for photography, if you can cope with the relatively low power, but that
    they will give slightly different results on every different film (or
    sensor) and will sometimes do strange things to particular materials
    (coloured fabrics that produce their colour by mixing a number of different
    shades - such as some silks - are the famous example of such problems.)

    Lots of photographers use flourescents for their particular qualities, but
    you need to test the results against your particular film - and be prepared
    for occasional surprises.



    Peter
     
    Bandicoot, Nov 19, 2004
    #5
  6. Peter Chant

    Gardner Guest

    What's the variation of brightness in a CF over an AC cycle? Probably
    2 stops at least. 100/120 hertz. With shutter speeds less than 1/60th
    you stand a good chance of hitting a dark spot, or a bright spot in the
    light's output and your exposure being off noticably.

    Frankly, I think they're a bad idea. Go with incandecent or LED.

    ============================================================
    Gardner Buchanan <>
    Ottawa, ON FreeBSD: Where you want to go. Today.
     
    Gardner, Nov 19, 2004
    #6
  7. I recommend the ones labeled, "warm white".......
     
    William Graham, Nov 19, 2004
    #7
  8. Peter Chant

    Owamanga Guest

    Good point.

    LED? Are these commercially available - bright enough to do this?

    ....beware, most LED driver circuits pulse the power to the LEDs, (so
    it can run brighter than spec, but not burn out, and to save power) so
    it would have to be built specifically for this job, otherwise you'd
    get the same problem.

    I actually bought a 100 white LEDs on ebay (really cheap) last year
    and never considered making a soft-box. It would be lightweight (could
    even make it out of styrofoam board, just punch the LEDs right through
    it), fairly thin and run cool too.

    How to measure the color temp of this box though? I guess a digital
    camera in it's 'set white level' mode would tell me.

    I've also got about 80 UV LEDs. Never been sure what to do with these.

    I might as well mount them all in the same box, with some reds, greens
    and blues so I can modify the color output for special effects. Couple
    of variable pots, and bingo!
     
    Owamanga, Nov 19, 2004
    #8
  9. Even your eyes don't :)
    Very good and complete response.
     
    Joseph Meehan, Nov 19, 2004
    #9
  10. Peter Chant

    Alan Browne Guest

    Yes, however,

    I was referring mainly to their (flourescent or LED) use with digital cameras
    which are a lot easier to setup for various kinds of lighting, and of course can
    be verified on the spot. For film, most studio work, esp. color critical,
    strobe is clearly preferred.

    Cheers,
    Alan


    --
    -- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
    -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
    -- [SI gallery]: http://www.pbase.com/shootin
    -- [SI rulz]: http://www.aliasimages.com/si/rulz.html
    -- e-meil: there's no such thing as a FreeLunch.
     
    Alan Browne, Nov 19, 2004
    #10
  11. Peter Chant

    Alan Browne Guest

    The slower shutter speed the better, yes. With flourescent and a decent DOF you
    will be shooting pretty slow in most cases. Personally I prefer strobe, but the
    fact that CF ganged lights are out there and aimed at the studio digital shooter
    is hardly ignorable nor necessarilly a bad idea.

    --
    -- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
    -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
    -- [SI gallery]: http://www.pbase.com/shootin
    -- [SI rulz]: http://www.aliasimages.com/si/rulz.html
    -- e-meil: there's no such thing as a FreeLunch.
     
    Alan Browne, Nov 19, 2004
    #11
  12. Peter Chant

    Alan Browne Guest

    ESD possibility?
    If you look at the link I provided, you will see the color temp specification.
    LED brighness is typically controlled with a pulse train and changing the pulse
    width (duty cycle if you will) to change brightness.


    --
    -- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
    -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
    -- [SI gallery]: http://www.pbase.com/shootin
    -- [SI rulz]: http://www.aliasimages.com/si/rulz.html
    -- e-meil: there's no such thing as a FreeLunch.
     
    Alan Browne, Nov 19, 2004
    #12
  13. Peter Chant

    Bill Tuthill Guest

    Aren't these too blue? The white LEDs in my flashlight and headlamp
    seem extremely blue. Maybe they are mixed with a few yellow and red LEDs?
     
    Bill Tuthill, Nov 19, 2004
    #13
  14. Peter Chant

    Bruce Murphy Guest

    'white' LEDs are blue LEDs with a fluorescent material.

    B>
     
    Bruce Murphy, Nov 19, 2004
    #14
  15. Peter Chant

    Alan Browne Guest

    They do have a strong component at 6500 - 10,000K which is something like
    northern exposure / open shade. But this is also combined with warmer light at
    the same time from the same LED's (If I'm interpretting the spec sheet right).
    Again, as these products are best suited for digital they can be adjusted in
    most cameras and verified ... or throw on an 81A/B to get there.

    Cheers,
    Alan



    --
    -- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
    -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
    -- [SI gallery]: http://www.pbase.com/shootin
    -- [SI rulz]: http://www.aliasimages.com/si/rulz.html
    -- e-meil: there's no such thing as a FreeLunch.
     
    Alan Browne, Nov 19, 2004
    #15
  16. Peter Chant

    Alan Browne Guest

    Another way to interpret the spec sheet, is that the LED's are available in
    "bins" A .. D with progressively higher color temp. I can't find the part
    number format, so it's a bit unclear...




    --
    -- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
    -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
    -- [SI gallery]: http://www.pbase.com/shootin
    -- [SI rulz]: http://www.aliasimages.com/si/rulz.html
    -- e-meil: there's no such thing as a FreeLunch.
     
    Alan Browne, Nov 19, 2004
    #16
  17. Peter Chant

    Owamanga Guest

    I see no link...

    ?
    Indeed, but we don't want that them to flash because it'll limit the
    choice of shutter speed. (Try taking a 100th/sec photo of an clock
    which uses 7-segment LED display)

    Of course, if I flash em fast enough it won't matter. I can do this
    with a 555-timer and a pot. One 555 can run 20 LED's. So 5 banks for
    the white and a bank each for red, green, blue and UV.

    Not sure about UV's behind a white diffuser, probably wouldn't work
    that well.
     
    Owamanga, Nov 19, 2004
    #17
  18. Peter Chant

    Owamanga Guest

    Sorry Alan, I missed your post the first time.

    To give you an idea on price, a pack of 60 super-bright whites can be
    "Buy Now'd" on Ebay for $0.10 + $15 shipping.

    ...or another one was 50 of em for $0.50 + $10 shipping.
     
    Owamanga, Nov 19, 2004
    #18
  19. Peter Chant

    Owamanga Guest

    Actually, the latest types are based on a UV led, not blue.
     
    Owamanga, Nov 19, 2004
    #19
  20. Peter Chant

    Bandicoot Guest

    Yes, digital makes it easier, and the on-the-spot verification (insofar as
    the little LCD screen tells you anything!) is a help.

    However, while a digital can adjust how it blends the signals from its three
    colour channels to address more or less any colour temperature, it still
    can't completely deal with a 'spiky' source. An extreme example would be a
    mercury vapour discharge lamp: whatever you do you won't get perfect colour
    balance with that, because it isn't a black-body (continuous spectrum)
    source, but has very specific, narrow, emission lines.

    Photographic fluorescents (and LEDs) have much smoother emissions than
    mercury or sodium vapour lamps, with many more, and less pronounced, peaks
    and troughs so the overall effect comes closer to a continuous spectrum
    source. This means you can come closer to correcting them in camera, with
    digital, and can _usually_ get full correction (if you relly need it) if
    you work hard after that in PS. And, as I said, for many subjects the
    results will look absolutely fine right from the start anyway.

    But both film and digital 'see' in terms of mixing three (or, for some
    films, more than three) colours, and so both _can_ have trouble with
    fluorescent sources and for exactly the same reasons. It's just that with
    digital you can adjust how those colours are mixed, so having the effect (in
    this respect anyway) of giving you a whole range of films to choose from.


    Peter
     
    Bandicoot, Nov 19, 2004
    #20
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.