If you want to calibrate a film scanner, you need a reference transparency. The best are reputedly the Hutch colour targets , but they are very expensive and in our experience don't justify their cost. Instead, you can use the industry standard IT8 calibration target. This will give you 98 percent of the results of using a Hutch colour target for about 20 percent of the cost. LaserSoft Imaging also manufactures IT8. SilverFast Blog. Version Feed.
All rights reserved. LaserSoft Imaging now provides color calibration targets according to the previous IT8 standard as well as according to the new design All around the world, companies trust the unflinching quality of LaserSoft Imaging Targets. Part 1 Targets use intelligent algorithms and important measurement points to calculate a calibration profile, while Part 2 profiles contain significantly more measurement points and Part 2 Targets possess additional measurement fields for dark and pastel color tones.
The profiles according to Part 2 thus enable an overall increased accuracy. Middle format transmissive targets IT8. Reflective targets IT8. Worth mentioning is the fact that the IT8 reference files have a standardized composition so that all targets with their reference files can be combined with every calibration software.
When using the scan software for profiling it will deactivate any adjusted image corrections like the brightness or the colors automatically. However when using an extra software for calibration you have to pay attention to do this manually. So put all controls back to their standard settings or you will receive a faulty profile! When the profile is generated it can be assigned to any image file which was scanned with this used scanner and you do not have to worry about additional lossy image quality.
For users who have flat bed scanners with a transparency unit is important that the created profile only is effective for the same type of sample which the profile was created with. A profile created with a transparency target slide applies only for slides and a profile created with a reflective target only applies for reflective scans.
SilverFast Ai automatically uses the appropriate profile because the software knows with the help of the made adjustments which type of sample is being scanned. If there is only one reflective profile then transparency originals will be output non-profiled and vice versa. Are there appropriate profiles for both types of samples than the software assigns the correct one automatically to the image file.
There are IT8 calibration targets for reflective and transparent originals on different film types and paper grades. This makes sense because the film- or paper type affects the color faults of the scanner differently. In the ideal case you use a target which has been made on the same material like the pictures you want to scan. However this is not possible in most cases since there is no IT8 target for each film type or paper grade.
In practice it is the best way to choose a profile created on a material base of the same manufacturer like the material you want to scan. When scanning pictures of a Fuji film you use a profile which was created with a Fuji transparent target, when scanning a Kodak film you use a Kodak target, etc. The last percentage points can only be achieved with a professional scanner and the use of a target type fitting the film material that is about to be scanned.
At our online shop in the product category IT-8 targets you will find plenty of IT8 targets with different dimensions and different film types. For example there are transparent targets for 35 mm film 25 x 36 mm or medium format 6 x 7 cm. But even a calibration with only one target whose profile is being used for all scans of different film types and paper grades comes with a remarkable improvement of color display. Further information for a target selection of different film- and paper types can be found on our SilverFast website.
Because a light source of a scanner suffers from variability which is affected by ambient temperature and light duration it is necessary for consistent good scans that the profiling is repeated regularly. The best possible result can be achieved if the scanner is calibrated every time before the actual scanning takes place. Usually this is not necessary. A calibration once a month is adequate in practice.
Only for professional devices, for example for painting reproduction, where achieving reliable colors is most important the daily calibration is required. Additionally it is recommended to calibrate a scanner if he was not used a while ago. In any case you should not think that a scanner only needs to be calibrated once after buying. The created profile can result can lead to damaging results after a while if it does not fit the actual state of the scanner anymore.
Professional users calibrated their scanner on a daily basis. For home users it is adequate when calibrating the device once a month. Since a scanner calibration only takes a few minutes you should make a fresh calibration once in a while for getting images with correct color fidelity. Like every analogue photo material IT8 targets suffer from image degradation as well. The aging process causes color shifting which enhances through the years. This can lead to unusable images. People who have thirty-year-old slides at home know how this is meant.
The aging related quality loss can be slowed down with the right storage of the materials: The best way to do so is in a cold, dry and dark place. This applies for reflective as well as transparent originals.
Unfortunately the aging process is not completely stoppable. Generally the date of manufacture is printed on the IT8 targets. For best calibration it should not be older than 20 years. But even then it can still be used for calibration if it was stored like described above. But beware: Even if the target does not show signs of color alteration it can be possible that the colors are not good enough any more to ensure a good calibration with the result of creating a faulty profile.
The IT8 standard does not allow for calibration of negatives. Due to the various orange masks of negatives with the resulting higher contrast it makes no sense to calibrate a scanner for negative material.
The IT8 calibration only works for positives. While getting obvious quality improvements from scanning positives with the help of IT-8 color calibrations, for negatives there is a special feature in the professional scan software SilverFast Ai Studio which leads to a considerable raise in image quality for negatives - the adjustments within the NegaFix dialogue.
With this SilverFast offers the possibility to adjust the film type of negative material so that certain color adjustments are made automatically depending on the chosen film type for image improvement. The benefit of image quality when scanning negative material is notable if you have chosen the correct film type. But this process has not to be mistaken with a scanner calibration since here the color faults of the device are not adjusted but simply the film characteristics are considered and used for image optimization!
The calibration does not make a good scanner out of a bad one. Lack of dynamic range, sharpness and resolution can not be adjusted by a color profile. If the color display if the scanner is originally bad a calibration does not necessarily lead to the desired result.
If the colors of the scan differ very strongly from reality the profile itself can not adjust those shortcomings without creating color disruptions because a certain amount of colors drop out due to the due to the intense color changing.
This is related however exclusively to the cheapest flat bed scanners which are available nowadays for a double-digit sum. The image quality of high class flat bed scanners and of course film scanners can be improved remarkably.
We already mentioned that a scanner calibration with an IT-8 target for negatives has no effect. The IT-8 calibration only brings quality improvement for positive scans of either transparent or reflective originals. How you set your display parameters should best reflect what works best for you when you are softproofing for printing. Mark: Thanks for the clarification. I intend to scan some of my POP contact-prints so I can share them on the web.
For that I wanted to come as close as possible to reproduce the tone of the real print when displayed on the monitor. I noticed that the if I let the scanner software Vuescan apply the profile generated from the it8 target, the resulting scan was more deviated strong green cast from the actual print than the "uncorrected" default scan.
Hence the question as to the source of this discrepancy. To start with, if you are sharing stuff on the web, colour management is what we call a "crap-shoot", because everyone who looks at them will likely be doing so with different monitors set in different ways. Ever gone into a TV store where they have a pack of TVs all displaying the same channel and every picture looks different? OK you understand. So beyond what you post, you do lose control over what people actually see.
From what you are saying about your Vuescan experience, it looks as if the profile you are using is no good. Perhaps generate a new one. I don't know what profiling devices and software you are using so can't advise. Tell us a bit about your profiling approach, equipment, software, settings, etc. Quote from: Mark D Segal on May 12, , pm. The target should be good. From what you say here, looks to me like either a Vuescan problem generating the profile, or an issue with the scanner hardware.
By the way, looking at those two images of the target you posted, neither of them are correct.
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