Filter Question

Discussion in 'Talk About Techniques' started by Ian-Barber, Mar 25, 2018.

  1. Ian-Barber

    Ian-Barber Admin Staff Member Registered User

    Joined:
    Aug 6, 2016
    Messages:
    712
    Likes Received:
    176
    Trophy Points:
    43
    Location:
    Doncaster
    Home Page:
    For those who have some experience using contrast filters in-front of the lens, can someone briefly explain the effect of using the following filters.

    Yellow (K2)
    Brightens Yellows
    Darkens ?
    Good for ?

    Hoya Orange (O)
    Brightens Orange
    Darkens ?
    Good For ?

    Cokin Green P004
    Brightens Greens
    Darkens ?
    Good For ?
     
  2. Graham Patterson

    Graham Patterson Member Registered User

    Joined:
    Aug 14, 2016
    Messages:
    65
    Likes Received:
    8
    Trophy Points:
    8
    Gender:
    Male
    Location:
    SF Bay Area, California
    Filters lighten themselves and darken colours on the opposite side of the colour wheel. How much effect this has depends a bit on exposure as well as the colour and brightness in the subject. If you spot-meter through a filter you can take that into account. Using factors, I tend to increase exposure a bit over the theoretical.

    Yellow tends to darken blues. It also darkens shadows in snow, sometimes more than one would expect if there is a lot of UV around.

    In California at the end of the summer, most of the grass is a light brown, so a yellow tends to bleach it more. Oddly, a green can actually darken it a bit.

    Orange tends to darken greens as much as blues. I think the only orange filter I have is in 40.5mm size, which shows how little I use one!

    Green can help separate different types of green. It can over darken skies, and anything reddish. It can tame the blue sensitivity of Ortho film, but you need to do some tests. It would not be a good choice with reddish light.

    Typically I carry a yellow or yellow/green, and a green. Most exposures are made without a coloured filter though. When I lived in the UK, I did find that orange can help with the Victorian red brick buildings and punch up contrast generally under overcast conditions.
     
    Ian-Barber likes this.
  3. alexmuir

    alexmuir Member Registered User

    Joined:
    Aug 14, 2016
    Messages:
    130
    Likes Received:
    19
    Trophy Points:
    18
    Gender:
    Male
    Location:
    Glasgow, Scotland.
    Yellow and orange are popular here in the UK for darkening blue skies, and creating more contrast with clouds. Orange is a stronger effect than yellow. I used orange with Ilford XP2 film and produced very dramatic skies. I tend to use yellow most of the time for outdoor photography. Yellow/green is preferred by some for landscape, instead of yellow. I’ve only really used it for portraits where it can darken the skin and reveal a bit more texture ( not ideal for everyone!!). I quite like the effect as it seems more natural.
    Alex.


    Sent from my iPhone using Tapatalk Pro
     
    Ian-Barber likes this.
  4. David M

    David M Active Member Registered User

    Joined:
    Jan 29, 2017
    Messages:
    437
    Likes Received:
    43
    Trophy Points:
    28
    Gender:
    Male
    Location:
    South London
    If you look at a colour circle (aka wheel), a filter lightens itself and darkens the diametrically opposite hue.
    The wheel's circumference might read R-M-B-C-G-Y- ... (and back to the beginning, R) so for example, yellow darkens blue and blue darkens yellow. I suspect that filters are not all pure spectral hues.
    There are several other valid ways of classifying colours, so it might be easier to think of a continuous rainbow spread around a circle, like the Apple beachball, to include intermediate colours such as orange and purple.
    [It's a curious accident of our perceptions that a rainbow strip, bent around to swallow its own tail seems to be continuous.]
    "What it's good for" is another kind of question altogether. Do we all like black skies?
     
  5. Ian-Barber

    Ian-Barber Admin Staff Member Registered User

    Joined:
    Aug 6, 2016
    Messages:
    712
    Likes Received:
    176
    Trophy Points:
    43
    Location:
    Doncaster
    Home Page:
    Thanks David, I know it can be a complicated subject and the explanation which Graham gave will give me a rough idea. My main issue is that I am red/green colour blind which can be frustrating at times. So if I use the Orange filter when photographing rocks or brickwork and there is some grass in the scene, the filter could darken the grass according to what Graham wrote.

    Take a strong rainbow for example against a dark sky. The most colours I have ever been able to see in a rainbow is 3.
     
  6. David M

    David M Active Member Registered User

    Joined:
    Jan 29, 2017
    Messages:
    437
    Likes Received:
    43
    Trophy Points:
    28
    Gender:
    Male
    Location:
    South London
    I see the difficulty. It must be inconvenient.
    Although it's no comfort, most people can only identify six colours in a rainbow. Indigo was inserted by Isaac Newton because he thought there should be seven colours. In his spare time, he had some unusual beliefs.
    The only practical suggestion I can make is search textbooks or manufacturer's literature and find a list of the effects of different filters, then use these in the field.
    I don't know if it's still true, but photographic textbooks used to have illustrations of something like a blue plate with a red tomato, a green apple and a yellow lemon with examples of the effect of different filters. As it's an easy subject to set up (and you seem to have an analytical and experimental frame of mind) it might be worth performing the experiment for yourself, but choosing objects (different green leaves, perhaps?) that you are most likely to photograph.
    I'm curious about how you see through those sludge-coloured "viewing filters".
     
    Last edited: Apr 3, 2018
  7. Ian-Barber

    Ian-Barber Admin Staff Member Registered User

    Joined:
    Aug 6, 2016
    Messages:
    712
    Likes Received:
    176
    Trophy Points:
    43
    Location:
    Doncaster
    Home Page:
    Do you mean the filters we are talking about?
     
  8. Stephen Batey

    Stephen Batey Well-Known Member Registered User

    Joined:
    Aug 6, 2016
    Messages:
    309
    Likes Received:
    57
    Trophy Points:
    60
    Gender:
    Male
    Occupation:
    None (retired)
    Location:
    Sussex - but originally from Wakefield.
    I'll just add that orange can bring out the grain in woodwork.

    Green works well at lightening and differentiating foliage. I carry a light and dark green (plus yellows, red, orange) as a standard set.
     
    Last edited: Mar 26, 2018
  9. David M

    David M Active Member Registered User

    Joined:
    Jan 29, 2017
    Messages:
    437
    Likes Received:
    43
    Trophy Points:
    28
    Gender:
    Male
    Location:
    South London
    Ian, not filters we are talking about.
    I'm afraid I've gone a little off-topic. These are filters that are supposed to give the eye an approximation of what a real-world scene would look like in monochrome. Fred Picker used to sell them but Zone VI is no longer trading. I wondered if they would help or hinder you.
    Here's a reference:
    http://www.jbhphoto.com/blog/2010/11/09/the-bw-viewing-filter/
     
  10. Ian-Barber

    Ian-Barber Admin Staff Member Registered User

    Joined:
    Aug 6, 2016
    Messages:
    712
    Likes Received:
    176
    Trophy Points:
    43
    Location:
    Doncaster
    Home Page:
    Ah. I have never really seen one but I understand AA used a Written #90 one which I am always trawling ebay for.
     
  11. David M

    David M Active Member Registered User

    Joined:
    Jan 29, 2017
    Messages:
    437
    Likes Received:
    43
    Trophy Points:
    28
    Gender:
    Male
    Location:
    South London
    Yes, it was a Written 90. Mr Picker mounted it in a circular frame with glass covers and a neck strap.
    I did try one, but didn't find it much use to me. Perhaps I am not very picky about tonal rendering. As I recall, the effect was rather like looking at a badly-made sepia print.
    I did have a naked filter but lent it to someone on a workshop and didn't miss it afterwards.
    There is one on eBay UK at the moment for £133.99 (!) from a company called SpeedySavings (!!) That's very nearly two hundred sheets of Fomapan. (150 sheets plus a nice lunch or a tank of petrol) The number on the packet on eBay UK seems to be 96 and not 90.
    There's a mounted Zone VI one on eBay.com for $72 together with a typewritten sheet describing Mr Picker's visit to an AA workshop, some of which is legible on screen.
    We might care to recall that AA made Moonrise without one. My guess it that AA used it as a training aid for B+W novices on his workshops. In The Making of Forty Photographs, I don't think he mentions that he used one himself. He does say: "Visualisation ... With practice, the photographer can anticipate ... intuitively..."
    I think this filter is a red herring in the original discussion and perhaps I shouldn't have mentioned it. My curiosity carried me away. The filter can have no effect on the photograph itself.

    [Does a red herring make blue sea look darker?]
     
  12. David M

    David M Active Member Registered User

    Joined:
    Jan 29, 2017
    Messages:
    437
    Likes Received:
    43
    Trophy Points:
    28
    Gender:
    Male
    Location:
    South London
    I said that the viewing filter was a red herring, and so it is. I was intending to say no more.
    However, if anyone wants to try it, Stearman Press, who make the SP-445 developing tank, offer one. It's not specifically a Wratten 90 but Mr Stearman claims that his version is slightly better and it's certainly very much cheaper.
    Morco now sell the tank so they might sell the filter. I don't know.

    Here is a reference to Stearman Press:
    http://www.stearmanpress.com/zoneview.html
     
  13. mpirie

    mpirie Member Registered User

    Joined:
    May 4, 2017
    Messages:
    118
    Likes Received:
    4
    Trophy Points:
    18
    Gender:
    Male
    Location:
    Highlands of Scotland
    I have a Wratten #90 viewing filter in a Zone VI holder which I use when i remember :) I also have a 75mm Wratten #90 in a card mount which is easier to use since it's bigger.

    I believe AA used it as a training aid to allow novices to see the relation between the different colours and how they will translate to tones in the B&W shot.

    All it does it remove the colours for a short while. If you look through it for too long, your brain starts to fill the colours back in, so the effect is lost.

    Mike
     
  14. Graham Patterson

    Graham Patterson Member Registered User

    Joined:
    Aug 14, 2016
    Messages:
    65
    Likes Received:
    8
    Trophy Points:
    8
    Gender:
    Male
    Location:
    SF Bay Area, California
    Ian, I sympathize about colour blindness. I can separate red and green, but I do have trouble with purple/violet. I had to do a direct comparison of bottle of chart recorder ink (years ago...) otherwise I risked getting the wrong one!

    Actually, viewing through a green (or red) filter ought to alter the brightness as long as you are not actually blind to the colour of the filter. I usually flip a filter in front and away from my eye to get a feel for the changes. It is the relative brightness change that you use to pick the colour. Of course, bricks come in colours other than red, too!


    Graham
     
  15. David M

    David M Active Member Registered User

    Joined:
    Jan 29, 2017
    Messages:
    437
    Likes Received:
    43
    Trophy Points:
    28
    Gender:
    Male
    Location:
    South London
    Graham has identified an important factor. The eye adjusts remarkably quickly (to spot the sabre-toothed tiger inside the cave, I presume) so a glance is needed, rather than a gaze.
     

Share This Page