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Filters for Black and White

Discussion in 'Colour or Not' started by FoldingCamera, Aug 19, 2010.

  1. FoldingCamera

    FoldingCamera Active Member

    When I started B&W photography in the 1970's and for many years thereafter I Have from time to time compared the effects of using either yellow, orange or red filters, generally the results of these comparisons were disappointing except that red filters always made the shadows very dark (shadows being blue). Recently I have been using folding cameras without filters of any kind and find that the sky does not just go white as the popular wisdom of the 1970's and earlier suggests, this is likly to be as a result of modern films having a more extended red sensitivity?

    I have even gone to the extent of trying my Canon lenses on FTb with a UV filter only with good results, good shadow detail and enough detail in the sky. I am not in a position at the moment to do much photography but this requires more trial to make any constructive opinion possible. I wonder I anyone else has tried B&W film without filters or with only a UV and their opinion of the result?
     
  2. El_Sid

    El_Sid Well-Known Member

    Modern black and white films are mainly panchromatic and as such have a more balanced spectral response with enhanced sensitivity to red light and thereby less bias toward blue and green. The white skies in old photograhs are usually the result of using either orthochromatic film - which is not red sensitive and has a strong blue/green bias - or early panchromatic types with only a limited amount of response in the red region.

    I've used modern films without colour filtration and have gotten clear sky definition. Red/orange filters do improve the conrast but more in the respect that they give a better starting point for contrast enhancement in the darkroom.
     
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  3. taxor

    taxor Well-Known Member

    I tend to shoot with a yellow filter (Cokin) permanently attached if I'm out in the hills. I like the overall tonality it provides and , I believe, provides a spectral response similar to that of the human eye. Using this with a polariser gives a nice blue sky without the empty shadows you'd get with using a red filter. It's true though, modern panchromatic emulsions are better in this respect than their older namesakes. Have a go with Ilford SFX; this has a useful extended red sensitivity with tonality and graininess similar to ordinary emulsions when used unfiltered.
     
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  4. FoldingCamera

    FoldingCamera Active Member

    I was under the impression that Ilford SFX had been discontinued but had a look at the film list at my supplier and see that it is listed at double the cost of ilfor HP5 which is the film I have been using most of all for the last 30 years and at the same time found that the film that I have been trying out, Fuji Neopan 400, has now been discontinued. this is a major disappointment as Ilford choose to print the frame numbers on the back of 120 film so feint that they cannot be seen through the red window.

    This is very annoying to say the least, I suppose it is because not enough people buy the film to make its manufacture viable, is this because it is not a particularly good film? I have seen somewhere the suggestion that B&W film sales were increasing or is the 'credit crunch' killing of sales?
     
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  5. taxor

    taxor Well-Known Member

    Stick with HP5 then. It's been my favourite film since I was grass-high to a knee-hopper. A yellow filter works well on skies and doesn't distort the other tones in the scene (I'm sure I said that in my previous post :)). A bit of basic darkroom manipulation will pull out the detail in the sky - esp. if you print split-grade.
    As for sales of trad b&w emulsions on the increase, I'm sure it will be a very small increase. I think more important is the fact that sales aren't decreasing any more indicating a small but loyal following to the trad. camp.
     
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  6. FoldingCamera

    FoldingCamera Active Member

    There is another factor here in the use of uncoated lenses of prewar cameras, and perhaps early coated lenses, in conjunction with the increased red sensitivity of modern black and white film, in this case Ilford FP4, which I frequently use on 6x6 producing a different tonal range to a 1970's multicoated lens? yet another factor may be that all of my negatives are scanned into my computer with an Epson 4990 scanner (Flatbed), with the majority of image adjustment done before scanning.

    As a point of interest I was having a look in my copy of BJP annual for 1967 and notice that quite a few B&W glass plate negatives were still available, most neg mats were panchromatic with a fair amount of ortho still available, perhaps most surprising is that blue sensitive glass plate by Ilford was still available!
     
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  7. Dan S

    Dan S Well-Known Member

    Do filters work the same with digital cameras as they do with film? Or might it best to apply filters in the editing process?
     
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  8. Andrew Flannigan

    Andrew Flannigan Well-Known Member

    You do seem to like resuscitating very old threads. ;)

    The answer is that filters work the same no matter what sensor is behind the lens, subject to which frequencies the sensor is sensitive to. In other words: a red filter will have a different effect on the image formed by an infrared sensor than on the image formed by a sensor designed to be sensitive to visible light.
     
  9. Dan S

    Dan S Well-Known Member

    Oh dear, yes I've been reading some of the old threads and didn't want to start a fresh one unnecessarily, i'm not sure of full forum etiquette as yet. But thank you for taking the time to reply. I do like the idea of using filters but I'm also wondering if I might just as well do it in the editing phase and save my time and trouble experimenting?
     
  10. PeteRob

    PeteRob Well-Known Member

    There is no etiquette issue. The main thing that happens when an old thread is resurrected with a new question at the end is that people revert to answer the original query - and often this is only tangential to the new question. Then it all gets confusing. So it is usually easier for all to ask questions afresh.

    The other thing that happens with old threads is that someone answers it not realising that the likelihood of whoever asked the question being still involved is slim to say the least.
     
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  11. Dan S

    Dan S Well-Known Member

    That makes perfect sense
     
  12. El_Sid

    El_Sid Well-Known Member

    Essentially no. I have tried using coloured filters, particularly red and green, and other than minor changes to the overall contrast the end results are nothing like as effective as applying the filters digitally in post processing. Digital sensors don't respond in the same way as B&W film - the result of using a strong colour filter is a strong colour cast to the image rather than an improvement in contrast.
     
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  13. steveandthedogs

    steveandthedogs Well-Known Member

    IR filters work on digital cameras!

    Fuji and Pentax anyway.

    S
     
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  14. El_Sid

    El_Sid Well-Known Member

    Indeed they do... Depending on the type they cut out everything but the IR and the lower red end of the spectrum. The typical IR filter is the 720nm (R72) which is opaque to any light below 680nm so only IR and a very small amount of red is recorded. Effectively the camera becomes a monochrome instrument and simply records the intensity of IR light reflected from the subjects(s) to create the image. The picture ends up with a red cast because the camera's WB and software is not designerd to cope with IR and attempt to create colour which isn't there. If a custom white balance is used the resultant image is almost colourless. Other types of filter use different ranges and give slightly different effects.

    Most modern cameras incorporate much stronger IR cut filters in the sensor assembly than old ones. My old Nikon D50 averages around 1-2 seconds at ISO400 while the D7000 is more like 15....

    I've tried using a standard red filter with a custom white balance but that still doesn't produce a decent mono result either...
     
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  15. James Kirk

    James Kirk Member

    Hello, my question refers to the method where by respective RGB colour filters can be used on grayscale cameras to individually record grayscale 'colour filtered' images from life so they can be combined in post production to provide a full colour image. (Forgive the lengthy intro, it's for the benefit of clarity).

    Bearing the above, I wonder if there is a way within a 'grayscale image' (such as a b/w photograph) to apply a (grayscale only) filter to replicate the same effect as using a 'red' filter over a monochrome camera recording from life (colours) - whether it be in post production or otherwise? And would like to know the equivalent for green and blue filters too!
     
  16. PeteRob

    PeteRob Well-Known Member

    hi James, it is generally best to start a new question

    That’s basically how a digital camera works. The camera records brightness and a RGB filter array is used to provide pixel specific colour brightness information. Interpolation is then used to fill in the “missing colours” i.e provide G and B information for a R pixel.

    No you can’t. You need to have the 3 images as in your case 1. Mono images can be artificially coloured but that involves artistic judgement as to what the colours “should” have been.
     
  17. SXH

    SXH Well-Known Member

    The Leica Monochrom uses a non-colour-filtered, ie luminance only, B&W sensor. For that, I suspect the use of old style B&W filters would have the expected effect.

    People are always converting sensors to IR by removing the IR filter, dunno if it's possible to remove the Bayer filter...
     
  18. James Kirk

    James Kirk Member

    Thanks PeteRob. Yeah, I'm a newbie here so I posted in the wrong section. Apologies.
     
  19. James Kirk

    James Kirk Member

    Thank you SXH, I'll have to look in to that camera and understand that process better.
     
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  20. SXH

    SXH Well-Known Member

    Be warned - they are not cheap. And the lenses aren't either.

    My second comment was a bit silly - the Bayer filter is an integral part of the sensor, not removable - the Leica uses a custom designed one. Probably special firmware too.
     

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