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  1. #11

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    IIRC the older spot covers were 4mm. The newer ones 6mm. The 4mm lets less light in. This is a problem with bigger printers or dense negatives. I guess it might have been better with smaller prints. I don't change anything when I change sizes.

    http://www3.sympatico.ca/nick_zenten...3000/0011.jpeg

    Look at the diagram. The round top thing is clear. The second round piece [the one closest to the probe] is frosted.

    O don't use the under lenses diffuser. It's for intergrated mode.

    It may be the Fuji print isn't perfect.

  2. #12

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    Quote Originally Posted by pentaxuser
    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
    I'd either get a grey card and shoot it, or get a new target neg/print, a 10 year old target is not something I'd want to calibrate to.

  3. #13
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    Pentaxuser

    As others suggest the old negative and print that you have may be misleading.
    As other suggest try making a new negative with the film stock you most commonly use, Include a large *new*grey card a pleasing flesh tone and most importantly a area of nuetral gray that in a perfect setup would be lit from light to dark.
    The grey card will help you set up the analyser for nuetral grey if it has a probe to read this area., The flesh tone will be good for a basic flesh reading when setting up for images with people. In the old days we would set the probe just under the mouth and to the side to get a density reading for flesh* an area that is not in shadow or highlight.
    The graduated background is useful for seeing quickly any colour inbalances as the colour will show itself in a graduation better than a flat field of grey like a greycard.
    Having a lot of vibrant colours in the scene will only confuse the issue as different papers have *basically falloff* and will record some colours differently and this is what is happening to you with the fuji test negative.
    Remember that in colour printing the complimentary colour theroy, and if you are trying to colour correct lets say add more blue, you are basically making the yellows *suffer* or be less pronounced.

    For our balancing our product here we use a 21 step grey card and basically when each step is nuetral and equal density from each other we are ready to print. We do not look at the colour patches at all which seems to be odd .
    The Kodak Shirleys are the same and I remember balancing to nuetral the analysers for a under neg, normal neg, over neg, this created a balanced slope for different types of exposed negatives.

    I don't know if the above ramble is of any help, but try to start very simple and nuetral , when sorting out a analyser. As time goes on you will find out how to probe different scenes properly . If you find you are always light in your balances or off colour in one direction, you can easily adjust the analyser.

  4. #14

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    The grey card method is fairly straight forward with this analyzer. A little repetive but simple enough.

    1) Stick a film with a full grey card image into the enlarger [Colour negative, B&W Negative or colour slide just use the one that matches what you need to program]

    2) Project the image on the baseboard with the lens wide open.

    3) Analyze the projected image. Adjust the filters to null out the lights. Then adjust the F/stop so you get 5 seconds on the timer.

    4) Expose and process a strip about 1" wide. Make sure half is unexposed.

    5) Dry it. Hair dryer helps alot.

    6) If it's too wide to fit the probe opening cut it to size. Place the unexposed part under the probe after you've removed the negative from the enlarger and opened the lens up. Zero the analyzer with white part in the probe. Then measure the exposed part.

    7) Write down the readings. IIRC you're looking for 0.55 on the channels. If it's off that by more then say 0.02 then hit the reprogram button. That will adjust the analzyer.

    8) Go back to #1 repeat until the values are 0.55 or fairly close to that. If you don't start too far off it won't take many test strips to get things right. Maybe 3? Something like that.

  5. #15

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    Thanks for the additional replies. I will have a go at the grey neg method of calibration. I had begun to come around to this way of thinking but your replies have just reinforced that.

    There is another issue that I need to raise which I hope you will say will go away once I calibrate properly on a grey neg.

    Having calibrated on the Fuji neg and "perfect print", the process I followed from the manual seemed to do exactly as the manual said it would. Once calibrated I then used the Fuji neg as if it were a new neg just as a test that I had done things correctly. The analyser on the analyse sequence reproduced the filtration and time for the perfect print as I would have expected. So far so good.

    When I then moved to my own processed negs, most of them, on pressing the analyse button, seemed to light up the cyan part of the star. To null the star then required me to dial in some C so I ended up with Y, M and C which as I understand it shouldn't happen. So I have neutral density dialled in which increases exposure.

    I printed with all 3 colours dialled in and the prints looked reasonable colour balance-wise or not so far out as to have a noticelable cast. As an experiment I then noted the amount of C and attempted to subtract equally from Y and M. So I had say 42Y, 62M and 20C. I then nulled the C dial and attempted to null the Y and M. To null the M I had to reduce the M dial to 42M as I would have expected. However to null the Y I only had to reduce the Y dial to 30 NOT 12 as I would have expected. This print at 30Y, 42M and OC was appreciably warmer than the 42Y 62M and 20C again as I should have expected. I suppose I really needed to dial in 12Y, 42M and OC and just ignore what was happening on the LEDs to see if this would have replicated the original colour balance but I imagine it would. I didn't try this as I had run out of both time and patience and I am going through a lot of paper without getting anywhere.

    Maybe I could get to the bottom of what is happening here eventually but I am so unfamiliar with the colourstar.

    Any suggestions as to what is happening? Why should I be able to replicate the Fuji balance when I treat it as if it was a new neg and in so doing the C LEDs don't light up but in changing to other negs the C LEDs do light up and I end up dialling in C to null the star.

    I wondered about the effect of my DUKA sodium light being on. I hope I can dismiss this as a cause. It wasn't a problem with my Paterson analyser and I would have thought that even if it does affect the exposure reading then provided the best exposure was arrived at with it on and that is calibrated in then other exposures should be OK. My prints seem OK exposure wise.

    If having it on affects the analyse function in terms of colours then I would have to print in total darkness but I think I'd go back to the Paterson rather than struggle in the darkness. The DUKA is not a light that you can turn on and off, given the time it takes to get to its correct operating wavelength. There is a dial on the lamp you can turn to zero. This moves a metal cover with slits round the lamp to cut out the light as opposed to turning it off but even at zero some light escapes.

    I am getting a little downhearted. You guys are doing your best with me but it's a little like learning to operate on your own appendix by exchanging e-mails with a doctor as opposed to watching him doing it on several people and then having a go.

    Thanks for your patience

    pentaxuser

  6. #16

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    Quote Originally Posted by pentaxuser

    When I then moved to my own processed negs, most of them, on pressing the analyse button, seemed to light up the cyan part of the star. To null the star then required me to dial in some C so I ended up with Y, M and C which as I understand it shouldn't happen. So I have neutral density dialled in which increases exposure.


    Any suggestions as to what is happening? Why should I be able to replicate the Fuji balance when I treat it as if it was a new neg and in so doing the C LEDs don't light up but in changing to other negs the C LEDs do light up and I end up dialling in C to null the star.

    I wondered about the effect of my DUKA sodium light being on. I hope I can dismiss this as a cause. It wasn't a problem with my Paterson analyser and I would have thought that even if it does affect the exposure reading then provided the best exposure was arrived at with it on and that is calibrated in then other exposures should be OK. My prints seem OK exposure wise.

    You can check if the light is causing issues by first analyzing with it on. Then trying with it off. If it's not a problem you'll get the same results.

    Do the at least one grey strip test and see what the box tells you. Come back and tell us how far you are from the targets. My guess is you aren't on target but close.

    Are you keeping the lens wide open when you analzye? Max amount of light? I only see the C lights when I stop down the lens. Not an issue then. Get the filters right then stop down and get the time right.

  7. #17

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    Thanks Nick. If I have understood you correctly when I insert a new neg I press analyze on full aperture i.e. f2.8. with my 50mm lens. So colour balance is done on full aperture then I stop the lens down to get a "proper" exposure which I think the manual suggest should not be less than 3 secs and ideally not more than 10 secs.

    Presumably I get to a reasonable exposure before the light level via stopping down drops to a level at which the Cyan LEDs come on or if they come on then it doesn't matter as the dials have been already set and do not require altering and I should just ignore the C LEDs.

    I hadn't realised that analyze should be done at full aperture. Either the manual doesn't make that very clear or more likely I am overwhelmed by it's depth.

    pentaxuser

  8. #18

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    Might not be mentioned in the manual. It might be buried in the section on low light use.

    You've got it easy. When I got my unit the probe was busted. The analyzer would do the exact opposite of what it should do. That was fun

    3 to 10 seconds should be a safe number. I use more then 10 when need be with Kodak paper without any problems.

  9. #19

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    Nick, Ed and Bob. I think this is primarily addressed to you as you seem to be the ones with colourstar 3000 knowledge. Ed I hope your new machine is now fully operational

    I have now tried the grey neg calibration as recommended by Nick, following the instructions in the F Schultz article. I tried to see if my DUKA affected the analyser and at a light setting of 10 it affected the exposure by 0.1 sec which is nothing but the M setting by about 6 which on a Durst head is appreciable. However at a setting of 5 which is just about enough to see, things were unaffected. So do you guys use a DUKA and if so how do you guys cope?

    I set the analyser as per F Schultz's starting values of 600Y 550M and D520. Like hers my first test was a dark blue grey. After 6 tests I managed to get to logD 0.55; logY 0.56; logM 0.55 and logC 0.56.

    The print still didn't look very grey in daylight but did under the enlarger's white light. I have had to assume that my negs are the correct negs to produce a correct grey print but as there are three packs of negs with the analyser for B&W, colour neg and colour pos then it seems likely they are the correct negs for the test.

    Anyway folowing the grey neg test print calibration, I thought I'd try a neg I had recently developed and the print looked far better than the one produced from the same neg but based on my Japanese girl in garden test neg on which I had previously tried to calibrate and have previously talked about.

    My neg was a coastal scene with cliffs, people in the foreground and a large area of sea and a little sky. I think I had used a polariser. The sea and sky were very blue as I would have expected and looked great but overall the print was a little overexposed and some clothes which were blue looked a very dark blue which I assumed to be the result of overexposure.

    I wondered if I could correct the problem if I continued to test print until I had all the readings at 0.55. Big mistake. The next test print's readings were all under 0.55 by 0.02 .

    Anyway I continued to do grey neg test prints all evening but have ended up farther away from 0.55. By the 10th test print I was at 0.60.

    At these log readings of 0.60 the YMC I have dialled on the dichroic head has only changed from 69Y and 54M( getting me very close to 0.55) to 69Y and 53M which seems strange.

    The two proper prints I have done are too blue and too dark.

    I notice that if I colour analyse at full aperture with filters in the way and then attempt to get to 5 secs by stopping down as the manual advises then one green LED
    and a red LED usually light up. I can then remove both by dialling in some C and M and I then attempt to remove all LED lights by reducing the Y and M by the amount of the C dialled in, then removing the C. This usually gets me close to( but not the same as) my original Y and M at full aperture.

    Can you confirm once again that in fact I should analyse at full aperture ensuring all LEDs are extinguished and then just ignore any yellow red or green LEDs that light up on stopping down.

    I have the colourstar density strip which is simply a piece of paper and is presumably meant to be used to compare the grey of the test print with the various grey log densities. When I compare this strip to my grey neg test prints, they don't look as grey although the density as far as I can tell looks similar.

    My Y M and D values ended up as 605, 566 and 497 on the test prints which came closest to logD,Y,M and C of 0.55

    I suppose I could decrease the D and Y channel values until I got a lower exposure and decreased the blue in the print but that's back to the guessing game approach which I had thought the grey test neg print would avoid.

    Should I simply stick with the calibration I have got and try to programme a channel for semi integrated analysis. If so it isn't clear to me how I determine a neutral section or which points I measure on the neg of the coast, cliffs and people to get a better v balance. Would this lower the exposure reading which is what I need as well.

    I really don't know how to proceed from here. There are so many variables involved.

    Any advice will be gratefully received. I suspect I may need to be talked through this. The colourstar should only be sold witth a course of instruction. It still puzzles me

    Thanks

    pentaxuser

  10. #20

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    You can make your own grey negative if you're worried that the ones you have are faded or whatever. Just prop up a grey card in daylight and fill the viewfinder with the image. Then process.

    Any chance your paper is off? The grey strips should look grey under daylight. How white is the unexposed section?


    Yup analyze full aperture then ignore the leds when you stop down. The Jobo website used to have an article on doing large prints that mentioned the method. I don't know if it's on the Omega website now.

    The Y etc numbers change with the probes. Different probes will calibrate differently. That's why on the bottom they have handwritten numbers to start with. If you have a notebook keep track of the numbers when you reprogram. It helps keep track of the chemicals.

    How did you analyze the prints you made? Spot mode? If so what spots did you choose? It does take a little learning to get a good feel for picking the spot points. If you did use spot mode then try picking some different spots and see how that affects the filter pack and exposure. Don't even need to make the prints. Just see how different choices change the filters and time. You said the print is overexposed so I'm thinking you picked too many spots that are dark coloured.

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