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  1. #1

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    Changes in enlarger filteration depending on size of enlargement!

    Good morning guys, welcome to my first thread on the forum. I primarily work with colour using Ilford 2000 paper and what ever RA4 chemicals I can get my hands on. Currently I am using the SpeediBrew RA4 kit which although cheap is exhausted quickly. As a lot of my images are from a Holga, I usually work on a small print 6" until I get the right colour and dmax from the print. What I have noticed though is when I come to do an enlargement I need to increase the yellow filtering. I cant understand how the colour filtering should change depending on the size of the enlargement. I am keeping the light hiting the paper the same and I am keeping the exposure time the same. Chemicals are pretty fresh temperature is at 35c for 45 seconds before 10 seconds fix then 45 seconds BLIX. Exposure time is 5.5 seconds, I am using a Meopta Magnifax enlarger and putting the paper through a Nova processor. Oh and the lens is a Schneider Componon. Anyone else experience this?

  2. #2
    Marco Gilardetti's Avatar
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    Forget it. I didn't read your MSG well before answering. Of course you didn't change paper batch, did you?
    Last edited by Marco Gilardetti; 01-31-2006 at 04:50 AM. Click to view previous post history.
    I know a chap who does excellent portraits. The chap is a camera.
    (Tristan Tzara, 1922)

  3. #3
    Mick Fagan's Avatar
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    There is one change that you are doing, you are changing the aperture on the lens to keep the exposure constant.

    I can, at this stage, only assume that the colour of the light changes, as the lens is opened up.

    I myself don't use this method, as when I do a big enough enlargement, I run out of aperture on the lens.

    There is a lot of talk about colour change when you change the time the lamp is on. I haven't really experienced much of a colour change when changing times as I roll the enlarger up.

    I have at times, gone about 2½ stops more light required and haven't noticed a change. Which doesn't mean to say the colour hasn't changed, just that for all intents and purposes, I cannot notice any colour shift.

    Yellow is the weakest filter change, so I assume that you must be changing the filtration a fair bit to keep the colour consistent.

    You are using the same paper out of the same box, or are you using a different box of paper for the enlargements?

    Mick.

  4. #4

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    Hmm, some interesting points, The aperture is usually 1-1.5 stops greater, as the Magnifax has a ND filter of a range of 2 stops I usually try and use that so I wouldn't expect too much change in aperture. The enlarger is pretty bright so I am at f8 for 5.5 seconds on a 10" enlargement.
    Change in colour depending on length the head is on is a strong possibility; The reason why I think this is I have a Philips colour analyser, when programming it you need to leave the lamp on for 5 seconds for the yellow and magenta to settle down, the yellow taking the longest, around five seconds and it oscillates. Changes to the filtering is 2 for magenta and 8 for yellow, the filters max out at 200. So I will have C36 M40 Y8 for a 10" and C36 M38 Y0 for a 5" print. A solution I guess would be longer exposures, or just stick to a fixed height and test strips. The changes are not a great amount, you get far more from the lighting you use to view the images under, it just getting the filtration to hit the sweet spot with this paper which is tight.
    Meopta Enlargers are very utilitarian and I have considered replacing it but TBH its solid and apart from a large format enlarger its the only one I know that will do an oversized 6x9 neg.

  5. #5

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    I doubt changing the lens aperture is an issue.

    "C36 M40 Y8 for a 10" and C36 M38 Y0 for a 5" print"

    Is that right? No yellow but Cyan? Also those changes aren't very much. How are you deciding what the right values are?

    Assuming you're using the analyzer one possible issue might be how sensitive the probe is.

  6. #6
    Ed Sukach's Avatar
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    Using that much cyan filtration Is strange. Usually, if the negative is exposed with the proper film (Daylight balanced in daylight) or proper filtration, only magenta and yellow will be necessary.

    What film are you using, and what was the lighting for exposure?

    I've used a lot of Ilfocolor ... I LOVE the stuff. Unfortunately it is nearly impossible to obtain any over here, now.
    Carpe erratum!!

    Ed Sukach, FFP.

  7. #7

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    Quote Originally Posted by Ed Sukach
    I've used a lot of Ilfocolor ... I LOVE the stuff. Unfortunately it is nearly impossible to obtain any over here, now.
    Adorama lists it on their Web site. At the moment, some sizes are flagged as being out of stock, but others aren't.

  8. #8

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    IIRC you can remove Cyan and add extra Magenta and Yellow. I don't know if it'll make a difference but at least the filter numbers will look more normal.

  9. #9
    lee
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    So I will have C36 M40 Y8

    doesnt this create some neutral density? that would cause extra exposure also, no?

    lee\c

  10. #10

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    1. Are you using distilled water?
    2. Is development time enough? Try to increase it slightly.
    3. Are you using enough chemicals? This could be a problem. You may have enough chemicals to cover the print, but not enough to keep consistency.
    4. Are you using pre-wet? If you do pre-wet and use distilled water for the developer and tap water for pre-wet then make sure to draingpre-wet water well.

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