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  1. #1

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    Setting up "perfect print" for colour analyser calibration

    I have recently acquired a Colourstar 3000( the 8 channel version and more questions on that later). I have a Paterson PCA61 which is much simpler to understand and because I was familiar with its method of calibration which is to use the "perfect print route" I was advised that this was probably the best way to set up the Colourstar.

    I had been given a Fuji test neg and a Fuji print from the guy I bought my Jobo from. I am pretty certain the neg and print are Fuji's own and were supplied to customers setting up analysers, doing ring arounds etc

    I think I have learned a lot from getting as close as possible to the Fuji print but a couple of things still puzzle me. I hope some of you can provide answers

    The test neg and print is that of a Japanese girl with a white cardigan in a garden, holding up a colour chart with writing above and surrounded by two colours of flowers( golden yellowand deep red) and a stone statue. In other words all the thing you need to test for colour balance.

    I have got close to the Fuji print in terms of the colour chart but the best filtration compromise leaves the golden yellow flowers not quite as golden. I can get close to the golden colour but only at the expense of making the print too warm. So I end up with correct flower colour but at the expense of an over tanned face. The red flowers are spot on.

    Somehow Fuji seem to have achieved a fairly neutral skin tone and a very golden set of flowers. Fuji's print also looks brighter. Almost as if a brightener has been added to the chemicals. I do use a stabiliser/brightener but can't match Fuji's brightness.

    In my print her white cardigan is slightly less white, her face more tanned and the three squares for the black, dark grey and mid grey are slightly more brown.

    My conclusion was that all this points to increasing Y and M slightly but when I do that with various small combinations of Y and M around the chosen filtration, it helps some things but at the expense of others.

    The Fuji print paper has no brand mark but has to be at least 10 years old as is the neg. It is also glossy whereas mine is lustre. This may account for my print looking slightly less bright.

    In summary the main difference is my print has a more tanned skin tone yet a less golden flower tone.

    Any ideas as to how I might nail this down or could it be that a combination of different Fuji paper and a lustre finish as opposed to gloss might account for the differences?

    Thanks

    pentaxuser

  2. #2

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    Did you get the manual with the analyzer?

    I'd put away the Fuji neg. I would instead either get or make a grey card negative. Colorstar would have shipped one with the unit but you can make one yourself. Take a photo of a grey card. Fill the negative with the grey card. Use this negative with the grey negative setup mode to get the analyzer programmed.

    Okay onto analzying the negative. How did you do it? Spot mode? It takes awhile to learn how get the right balance. You want the important points to get more control then the other points.

    I don't know the negative you're printing but I'd likely start by choosing:

    1) Her face [forehead]

    2) the white cardigan

    3) red flower

    4) yellow flower

    5) statue

    6) A second point of her skin tone. Bare arm? neck? Face?

    7) Her hair. I might have done this earlier to be honest

    8) One more point. Depending on the balance of the negative. If it's mostly one colour then avoid that colour.

  3. #3

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    Quote Originally Posted by Nick Zentena
    Did you get the manual with the analyzer?

    I'd put away the Fuji neg. I would instead either get or make a grey card negative. Colorstar would have shipped one with the unit but you can make one yourself. Take a photo of a grey card. Fill the negative with the grey card. Use this negative with the grey negative setup mode to get the analyzer programmed.

    Okay onto analzying the negative. How did you do it? Spot mode? It takes awhile to learn how get the right balance. You want the important points to get more control then the other points.

    I don't know the negative you're printing but I'd likely start by choosing:

    1) Her face [forehead]

    2) the white cardigan

    3) red flower

    4) yellow flower

    5) statue

    6) A second point of her skin tone. Bare arm? neck? Face?

    7) Her hair. I might have done this earlier to be honest

    8) One more point. Depending on the balance of the negative. If it's mostly one colour then avoid that colour.
    Nick. Thanks for reply. Yes I got a manual with the analyser. It refers to the 3000 which has a 100 channels and mine only has 8 but other than that presumably the manual supplied is identical. I intended to calibrate the analyser based on getting a print which was a duplicate of the original Fuji print. I didn't use the analyser initially to arrive at duplicating the original print. I assumed that until the analyser was programmed to the filtration and exposure needed to produce the "perfect print", there was no point in using it.

    I have three sets of negs with the analyser which I think must correspond to a B&W grey neg, a colour neg to produce mid grey( it's looks a bit like the colour mask you get with colour neg film) and a colour transparency neg to produce a mid grey.

    Presumably if I calibrate on the grey neg set up mode I should then get the Fuji neg to produce a print which matches the original Fuji print or if not then at least it will be a properly balanced print.

    As I said, my print on which I have calibrated the analyser is very close to the Fuji print except for the slight differences in the skin tones( mine is warmer) and flower colour( mine is not as golden)and the black to mid grey squares are very slightly brown. There seems to be just a hint of browness in her hair whereas the original is black. If I get the flowers golden then the whole print is warmer and the girl's skin tones are distinctly warmer than the Fuji original print. I couldn't reconcile what appears to opposites in terms of effect.

    To quote filtration and exposure values, I have calibrated on 38Y and 32M at 2.9 secs. 40Y and 32M at 3.3 secs matches the golden flowers but makes the skin tones even warmer, presumably a function of extra exposure. 40Y and 32M at 2.8 secs comes closer on skin tones but the white square starts to look slightly blue.

    Your reply has caused me to look again at my test prints and overall 44Y and 36M at 2.6 secs comes very close on the white to mid grey and black to dark grey squares and the white cardigan. It is lighter on skin tone and hair and the other coloured squares.

    If I were to increase exposure slightly this would increase colour saturation and might get the skin tone, hair and flowers spot on but what would happen to the white square and white cardigan?

    It's worth a shot, I think. Glad you made me look again at the prints.

    On a couple of other points.

    1. Your comment on taking readings from several points. Is this the process of averaging readings which I read about?
    2. I have the diffuser which fits under the lens and two kinds of diffuser other than the clear spot cover. One is a translucent cover and the other is the same cover but with an inverted white plastic dome underneath which has a hole in the middle about half an inch wide so the light from the enlarger is blocked once it passes through the translucent top except for this half inch hole. One is presumably for a semi-integrated process. This plus the diffuser under the lens is presumably for full integration. So what the inverted plastic dome cover for?
    3. In using the fully integrated process the manual says place the probe directly under the lens. As there is no point of reference as everything is diffused, is it sufficient to simply aim for the middle of the light rectangle i.e. placing the probe in the middle of the 5x7 rectangle if its a 5x7 print that's being projected.

    4. Finally is there a website or other source of information that helps. The manual is OK but seems to make unwarranted assumptions about the user's knowledge as most user manuals do.

    Sorry if this seems to be very basic but the way the 3000 works is quite different to the Paterson which is what I am used to.

    I had identified you and Ed as colourstar users on the site and frankly unless I had known of knowledgeable users, I doubt if I'd have bothered to get one. There's nothing worse than having a complicated tool that you can't use.

    Thanks

    pentaxuser

  4. #4
    hka
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    For an good practical explanation for using and calibrating the Colorstar 3000 look at the article of Frances Schultz, editor for Darkroom User Magazine. BTW the 3000 with 100 channels works the same as the 8 channel model. The only difference is that you can use the other channels for more different calibrations. I can tell you that this analyser is the best and easyist gear I ever bought for my darkroom.
    The link to this article is: http://www.xs4all.nl/~colors/info/articles.html
    After reading all your questions will be answerd.
    harry

    Release, the best you can do...

  5. #5
    Ed Sukach's Avatar
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    Nick
    Quote Originally Posted by pentaxuser
    ... Yes I got a manual with the analyser. It refers to the 3000 which has a 100 channels and mine only has 8 but other than that presumably the manual supplied is identical...
    I have three sets of negs with the analyser which I think must correspond to a B&W grey neg, a colour neg to produce mid grey( it's looks a bit like the colour mask you get with colour neg film) and a colour transparency neg to produce a mid grey.
    Presumably if I calibrate on the grey neg set up mode I should then get the Fuji neg to produce a print which matches the original Fuji print or if not then at least it will be a properly balanced print.
    Uh .. no, not necessarily ... the grey Color Negative sample furnished by JOBO / ColorStar/ Lici may not have anything like the base filtration of a "ten-year-old Fuji negative". One uses those samples to set the ColorStar to produce a "neutral gray test strip" ...

    Unfortunately I am **BURIED** with work at the moment... I am committed to providing prints for a models' portfolio, among *dozens* of other obligations .. and I can't take time for an extensive reply. I WILL - promise!! - when the pressure eases.

    I have both the manual for the "old" 8 channel ColorStar and the one for the 100 channel. When I get chance, I'll compare them.

    Right now my rump is directly over the swamp - filled with alligators - and rising rapidly!!
    Carpe erratum!!

    Ed Sukach, FFP.

  6. #6

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    Personally I've come to the conclusion the analyzer doesn't care about the film. Awhile back I got a head for my old Beseler. I installed the head and move the analyzer over. I couldn't wait to calibrate the new head with the analyzer so I just made a print. It came out fine. Made some more and they're all fine.

  7. #7

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    Quote Originally Posted by pentaxuser

    I intended to calibrate the analyser based on getting a print which was a duplicate of the original Fuji print. I didn't use the analyser initially to arrive at duplicating the original print. I assumed that until the analyser was programmed to the filtration and exposure needed to produce the "perfect print", there was no point in using it.

    I have three sets of negs with the analyser which I think must correspond to a B&W grey neg, a colour neg to produce mid grey( it's looks a bit like the colour mask you get with colour neg film) and a colour transparency neg to produce a mid grey.

    Presumably if I calibrate on the grey neg set up mode I should then get the Fuji neg to produce a print which matches the original Fuji print or if not then at least it will be a properly balanced print.

    As I said, my print on which I have calibrated the analyser is very close to the Fuji print except for the slight differences in the skin tones( mine is warmer) and flower colour( mine is not as golden)and the black to mid grey squares are very slightly brown. There seems to be just a hint of browness in her hair whereas the original is black. If I get the flowers golden then the whole print is warmer and the girl's skin tones are distinctly warmer than the Fuji original print. I couldn't reconcile what appears to opposites in terms of effect.


    1. Your comment on taking readings from several points. Is this the process of averaging readings which I read about?
    2. I have the diffuser which fits under the lens and two kinds of diffuser other than the clear spot cover. One is a translucent cover and the other is the same cover but with an inverted white plastic dome underneath which has a hole in the middle about half an inch wide so the light from the enlarger is blocked once it passes through the translucent top except for this half inch hole. One is presumably for a semi-integrated process. This plus the diffuser under the lens is presumably for full integration. So what the inverted plastic dome cover for?
    3. In using the fully integrated process the manual says place the probe directly under the lens. As there is no point of reference as everything is diffused, is it sufficient to simply aim for the middle of the light rectangle i.e. placing the probe in the middle of the 5x7 rectangle if its a 5x7 print that's being projected.

    4. Finally is there a website or other source of information that helps. The manual is OK but seems to make unwarranted assumptions about the user's knowledge as most user manuals do.

    Sorry if this seems to be very basic but the way the 3000 works is quite different to the Paterson which is what I am used to.

    I had identified you and Ed as colourstar users on the site and frankly unless I had known of knowledgeable users, I doubt if I'd have bothered to get one. There's nothing worse than having a complicated tool that you can't use.

    Thanks

    pentaxuser

    http://www3.sympatico.ca/nick_zenten...rstar3000.html

    That's the manual for the 8 channel. I've seen at least two different types of 8 channel but they only differ in how they plug in. Once you've got it turned on they act the same.

    I never liked the perfect print method to calibrate. It's too subjective. What happens when you make your grey strip? How close to the target are you?

    1) Yup it lets you make choices. It also lets you avoid problems caused by too much of one thing.

    2) I'm having trouble visualizing what you mean. I don't use the under lens diffuser. Are you talking about the probe covers?

    3) I don't do the intergrated. If you're in a rush it might be okay but using the other method isn't much slower. It lets you choose what's important and not over do what is most common in the image.

    Once you get it calibrated it's actually pretty simple to use. It takes a bit of time to learn which points to choose with the spot probe but not that long.

  8. #8

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    Quote Originally Posted by hka
    For an good practical explanation for using and calibrating the Colorstar 3000 look at the article of Frances Schultz, editor for Darkroom User Magazine. BTW the 3000 with 100 channels works the same as the 8 channel model. The only difference is that you can use the other channels for more different calibrations. I can tell you that this analyser is the best and easyist gear I ever bought for my darkroom.
    The link to this article is: http://www.xs4all.nl/~colors/info/articles.html
    After reading all your questions will be answerd.
    Thanks Harry. Perhaps I should have mentioned that I also got a copy of the Frances Schultz aricle with the analyser. It looks quite good but of course describes the grey neg mode of calibration and only passing reference to calibration from a known neg and perfect print, as indeed that's all Frances could do in terms of this method.

    I am coming round to the conclusion that this grey neg method of calibration might have been better. What seems a quicker and easier method using the Fuji neg and print has turned out to be lengthy and frustrating. Primarily because try as I might I cannot replicate the Fuji print but don't understand why I can't.

    pentaxuser

  9. #9

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    Quote Originally Posted by Nick Zentena
    http://www3.sympatico.ca/nick_zenten...rstar3000.html

    That's the manual for the 8 channel. I've seen at least two different types of 8 channel but they only differ in how they plug in. Once you've got it turned on they act the same.

    I never liked the perfect print method to calibrate. It's too subjective. What happens when you make your grey strip? How close to the target are you?

    1) Yup it lets you make choices. It also lets you avoid problems caused by too much of one thing.

    2) I'm having trouble visualizing what you mean. I don't use the under lens diffuser. Are you talking about the probe covers?

    3) I don't do the intergrated. If you're in a rush it might be okay but using the other method isn't much slower. It lets you choose what's important and not over do what is most common in the image.

    Once you get it calibrated it's actually pretty simple to use. It takes a bit of time to learn which points to choose with the spot probe but not that long.
    Thanks Nick. My spot probe cover is just as is shown in the manual i.e. clear plastic with a hole and underneath on the bottom of the plastic, again as in the manual is a slightly diffused piece of plastic. This seems to be in exact accord with the manual. The manual also shows an intermediate piece of plastic which fits on top of this bottom piece of diffused plastic. This has a 4mm hole and is called the 4mm spot disc. It is used for small prints(unspecified).

    I don't have this 4mm spot disc. 2 questions. 1. Is this spot disc clear plastic? 2. What is small prints? I am presuming that anything at 5x7/8 is small. I often do 5x8(I get two prints per 8x10 that way). Will I need this spot disc or could I get away with the normal spot disc? If it's clear plastic then no problem as I could probably shape it myself or get a friend who has access to an accurate machine for plastic cutting. If it is a diffused material then does it matter that its the exact diffusion coefficient of the original accessory. If it has to be an exact specification then do you know of a source. Shipping from N America might not be a high cost as it is very small and light in weight.

    Yes I am talking about the probe covers. One has a white translucent cover which is smooth on top and rough underneath( covered with small inverted pyramids). The other is the same except that if you turn it upside down so the smooth white translucent surface is on the table's surface then the underneath from the bottom of the cover is covered in normal white plastic and is shaped like a dome( like the kind covering indoor arenas) but the dome roof has a hole in the middle which is about half an inch across. So using it as probe cover would seem to only allow light to penetrate vertically to the actual probe with a few degrees beyond vertical but not allow light from the enlarger to enter the whole cover.

    The manual talks of a probe diffuser for selective integral measuring. It doesn't show the underside but I suspect it is the probe cover without the inverted plastic dome with a hole in the top of the dome. So it's a mystery. The manual doesn't seem to cover it in the accessory section.

    Finally separate to all this is a sheet of diffuser material which is 7x7cm and can be cut to fit under the lens like the red filter for B&W paper. I haven't used this but have used instead the Paterson diffuser material which seems to be a little more dense. If it is marginally more dense then is this likely to alter anything except may the amount of light getting to the easel?

    Mind you I have just discovered a mistake which is that full intergral reading is taken using the spot probe not the probe diffuser for selective integral measuring. I had noticed that I needed to increase the aperture opening as my LEDs, usually in yellow, often blinked indicating lack of light. No wonder as I had two diffusers under the lens.

    Finally I did change the filtration for the "perfect print" as I said last night. It's now almost spot on in terms of everything except that the print isn't as "bright" for want of a better word.

    I can only conclude that my paper is different OR the fuji neg( it has to be at least 10 yrs old) has deteriorated and producing a copy of the original print from this neg is now impossible.

    Thanks for all your help so far. I have a feeling that I will need to seek more help in the days/weeks to come.

    pentaxuser

  10. #10

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    Quote Originally Posted by Ed Sukach
    Nick

    Uh .. no, not necessarily ... the grey Color Negative sample furnished by JOBO / ColorStar/ Lici may not have anything like the base filtration of a "ten-year-old Fuji negative". One uses those samples to set the ColorStar to produce a "neutral gray test strip" ...

    Unfortunately I am **BURIED** with work at the moment... I am committed to providing prints for a models' portfolio, among *dozens* of other obligations .. and I can't take time for an extensive reply. I WILL - promise!! - when the pressure eases.

    I have both the manual for the "old" 8 channel ColorStar and the one for the 100 channel. When I get chance, I'll compare them.

    Right now my rump is directly over the swamp - filled with alligators - and rising rapidly!!
    Thanks ED. Don't worry about not being able to reply as extensively as you'd like. What you've said helps already. Between you and Nick( and anyone else who is a colourstar user) I should eventually become competent

    I look forward to more correspondence in the future.

    pentaxuser

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