Konica Minolta FD-7
A spectrodensitometer measures color by scanning multiple spectral bands of light wavelengths and converting them into density or Lab values for use with printing presses or other color critical, industrial settings. These are expensive instruments ($6000 to $7000 or more), and very accurate. Considering the price, you would think they would do everything under the sun, but ironically they measure only one patch at a time. They cannot normally do scanning of multiple patches in a row in a continuous sweep. To have this "scanning" of patches, you need to get an additional, different instrument - a spectrophotometer - that will let you scan thousands of patches in a few minutes. This is what's done when measuring targets for building profiles for example.
The Konica Minolta FD-7 at first appears just another entry into the new generation of spectrodensitometers. But they keep adding features to this product that make it more and more useful in multiple ways. Besides incorporating the new industry measurement conditions and standards, the FD-7 gives you two devices in one: A press-side spectrodensitometer - and all the functions of a scanning spectrophotometer. Add to that a polarization filter to optimize the measurements of matte or canvas materials and you can do every kind of reflective measurements you would ever need, except for ambient measurements. So then they added the ability to do ambient light measurement too. And then it handles all the new ISO 13655 measurement conditions: M1, M2, M3, too.
Here's a quick look at its features:
Measurement Conditions M0, M1, M2 and M3
The FD-7 can measure according to:
- M0 (CIE Illuminant A)
- M1 (daylight)
- M2 (illumination without UV excitation (“UV-Cut”)
- M3 polarization (using the polarization filter accessory)
I have talked about these measurement conditions in other places, so I will just comment briefly here.
The reason M1 is so useful is that many papers nowadays have optical brighteners which fluoresce under normal (D50) daylight viewing conditions (that's what makes these white papers look "brighter"). Trouble is, most measurement instruments have artificial light sources that don't correspond to D50, so their measurements don't respond to colors the same way our eyes do. M1 allows you to measure these papers using the same D50 light source for which 99% of all profiles are made, and under which people are expected to be viewing. Measurements made in this way should reflect a little more accurately the way our eyes see things.
M2 is the UV-cut setting. It will cut out any effect of ultraviolet optical brighteners from the measurement.
Lightweight and Compact
Our demo unit weighs only 15 ounces, even with the target mask attached. If you're looking for a hefty hunk of machine that weighs enough to justify the money you spent for it…. well this is not the one. It's particularly light compared to existing spectrodensitometers. Besides the benefit of just being easier to carry around and use, the lighter weight really comes in handy when you use it to do strip readings for profiling targets. When you think about it, having to scan 2000 patches holding a 2 pound brick in your hand will get old pretty quickly…. which brings us to….
Strip (Scan) measurements
Rather than just measuring a patch at a time, this unit can also slide along an entire row of patches and measure the entire strip in one pass. A scanning "ruler" is included for this purpose. This is a big deal in my book. You can:
- Do your press checks with this instrument
- Do proof checks, scanning control strip bars, with this same instrument
- Measure profiling targets in scanning mode with the same instrument. (A firmware upgrade in the past few months has made this strip reading function even faster and more trouble-free.)
- Obviously, it will output spectral values and not just density & Lab.
Not only do you get the benefit of taking all your measurements with the same instrument, but note that all measurements will have the consistency from measurement-to-measurement that you get with a spectrodensitometer of this quality. In other words, it will be more accurate and more consistent than the consumer-grade, handheld spectrophotometers that are typically used to measure profiling targets. Which leads us to……
You get all this with an instrument that has a a spectrodensitometer level of accuracy. Published stats show an inter-instrument (comparing with other FD-7's) variation of just .3 dE2000, and a short term repeatability of just .05 dE2000. To put this in perspective we did a measurement study with IDEAlliance a few years ago where we found every handheld spectrophotometer in the study was at least 1.20 dE off from the reference in at least one color!
In real-life tests with our demo model we found a daily average variation of around .07 dE00 with a max of only .11.
Here at CHROMiX, we have been big fans of polarized measurements for many years and have decried the loss of instruments in the market that could provide this useful option. Several types of media can benefit when profiles can be built using polarized measurements of their profiling targets. The spectral highlights that bounce in several directions off the surface of glossy canvas, for example, cause havoc when trying to get a true reading of the color. Polarization cuts down on this scattering of light and can draw more shadow detail from profiles made in this way. There are very few scanning instruments made today that even offer a field-switchable polarization filter. Barbieri offers one with their table-based spectrophotometers. The FD-7 is the only other one I know of.
No external software is required to use the FD-7 to read single colors. Single measurements are shown on the the built-in display. KonicaMinolta offers free software called FD-S1w which acts like "Key Wizard" to upload measurements directly into the Excel spreadsheet program. This is only available for Windows.
"Catch" software is available from basICColor, which fully supports the FD-7 as well as many other industry spectros. This is available for Windows or Mac. At less than $300, this software does the job of driving the instrument to measure & scan targets and spot colors. Catch will save out the measurements in many of the more popular output formats (such as tab-delimited CGATS .txt or .csv files.) where they can be brought into the profiling engine of your choice to build a profile, or into an analysis program like ColorThink. For getting the easiest whole-line scanning experience like a spectrophotometer, the Catch software is essential.
Ambient light reading
This instrument comes with an ambient light diffusion head, and it can be used to take spectral measurements of any light source. Then that light source can be used when calculating data, producing profiles, analyze viewing conditions.
While KonicaMinolta is obviously a Japanese brand, they have facilities in the US, so that routine maintenance, recalibration, re-certifications can be done in this country and will not have to be shipped overseas.
There are many other features that will be useful to those needing a spectrodens for press readings:
- A Target Match function displays the color difference of an ink from the target color and the density adjustment needed to bring the ink closer to the target color, allowing for better quality control of spot and process colors.
- A gray balance feature allows for grays to be evaluated using the G7® specification method.
- It can do pass/fail judgments against user-defined targets and industry designated targets such as ISO 12647.
- It can be used untethered to take spot readings.
- The backing conversion feature allows the instrument to compensating for backing differences. We had a need for this recently. We needed to create a profile for newsprint where our customer printed on the backside of the thin newsprint, allowing the back colors to be visible through to the target side. When we lay the target down against a "black" backing, our measurements get less of that bleed through from the other side. That's good, as the readings are less influenced by the color on the back. But measurements made using a black backing tend to be darker compared to white backing, and the profile can end up looking "darker." So this conversion function can be used to make the black backing readings "brighter".
If you are in the market for a new spectrodensitometer, one that will handle the new 'Measurement Conditions', you already know how expensive these are. The Konica Minolta FD-7 is not cheap. But a great benefit of the FD-7 is that you can get two measurements devices in one, in such a way that the advantages of both are retained in the one instrument: speed, convenience and accuracy.
- "Scanning with an FD-7"