Debugging Profiled Inkjet Printing Issues.

Printing should just work, but often it doesn't, and you have doubts about the colors. I'm going to show you a quick way to figure out whether you have a hardware problem, or whether software issues are corrupting your profiled printing workflow. The key step is to get some original vendor paper and make a print with the vendor workflow aka. "Printer Manages Colors". This print then acts as a reference baseline for debugging, and finding issues becomes a matter of comparison, not absolute judgement.

The debugging process I detail below leads you through three steps. First you get some of the printer manufacturer's paper, and make a print with vendor settings. Then you make a print with the manufacturer's own profile; finally you make your own profile and print for the same vendor paper. The condensed set of steps, is followed by some explanations about vendor color and canned profiles.

Diagnosing Profiled Printing Issues: The Procedure

1. Set up the vendor workflow with "Printer Manages Colors" and make a nice colorful test print on vendor paper, making sure to choose the right paper type in the print driver dialog. If the print made with the vendor workflow looks ok, then your hardware is working well. If the print is  bad then  you might have a hardware issue eg. a clog, or you might have inappropriately chosen, fiddled with or otherwise corrupted the paper and color settings, so you need to clean the printheads and need to reset the default values for the print system and then make another test print.
2. If the print from (1) looks ok, then set up your usual profiled workflow, and make a test print using the same vendor paper, the paper settings validated in (1), and the vendor's canned profile. If this print does not match the  print made in (1) then your profiled printing workflow is compromised by inappropriate settings or some other software issue —vendor profiles should always match vendor color.
3. If the print made in (2) with the vendor's profile looks ok, then your hardware and profiled printing workflow is good. Now it's time to focus on your own profiling technique. Make a profile of the vendor paper yourself to compare with the vendor's profile. To print the profiling testchart the safest thing to do now is to make use of Adobe's ACPU utility, using the same paper settings as in (2), and then scan the print with your favorite spectro and software to create a new profile. Now make a new print with the profiled workflow. If this matches the vendor color print in (1) you are done, just go ahead and profile your own media. However if your own profiled print on vendor paper does not roughly match the print in (1) then you probably have an issue with the profiling process itself —hardware or software— and should call the profile tool vendor for support.  

Some explanations. 

Making profiles and printing with them is a fussy business, and many of us would prefer that "it just works". The good news is that Epson, Canon etc realize users want an easy solution, and they provide one: If you have  decent modern printer you will obtain decent  color from any app —and Photoshop —by just selecting "Printer Manages Colors" in the print dialog, and specifying the paper you have loaded. This is sometimes called Vendor Color mode. 

The nice thing about Vendor Color is that it is almost foolproof. To make it work correctly you just need to reset the printing system, make sure you have the right paper type selected, and make sure that there are no leftover color bias settings hidden away in your print dialog.

Of course there is a price for the simplicity of this workflow: you must use the manufacturer's paper, and for neutrals to stay neutral and color prints to be really spot on, you should have one of the more expensive printers which have several gray inks, and whose manufacturing tolerance is so good that it closely matches the canned profile. Incidentally, the printer driver's Black and White Mode works great on these models. 

Vendor mode is also a great debugging tool, because on their own papers Epson delivers very closely matched results by using vendor mode and by using their own canned profiles.  So to see whether your color-management printing setup is working, you just need to locate the canned profile for your paper and print with it using color management - this is called printing in Application Color Mode. 

And how do you find the canned profiles for your printer? Well, on Macs at least, the profiles should  already be there in your color management dialogs. Otherwise, if you open the Colorsync utility, and select the printer, the installed printer's profile paths will be displayed for you. 

Printing an image in Vendor mode should show you whether your printer is set up correctly and working ok. Printing in Application mode and comparing with the vendor mode should tell you whether color management is working ok. Your last problem if you do wish to profile your printer is to print a testchart with no color management - to do this it might be best to download Adobe's dedicated ACPU utility which excels at printing charts. 

Edmund

Sanity checking the i1Pro2 vs iSIS

I own this very nice 18th century antique card-table, and on the green baize sit the little i1Pro2 and an iSIS XL. The iSIS XL is Xrite's top of the line desktop scanner which can read 5000 patch single-page A3 charts. The i1Pro2 is the recognized swiss army knife of instruments, a universal handheld spectrophotometer which can calibrate screens and projectors, profile printers, and take ambient light measurements. The two instruments have been getting friendly and comparing measurements.

Checking instruments against each other is something ever color geek does occasionally to detect hardware issues. I also wanted a sanity check so as to know whether profiles which I make in the field or which others make with the i1Pro2 will match those I make myself at home with the larger spectro. I will be running some more rudimentary checks with the DTP70 and the Barbieri LFP within the next few weeks. 

By using the compare feature in the i1Profiler software we can read in data from two charts and compute some comparative statistics. Here, on the i1Profiler 400 patch RGB chart, we have a max deltaE of 2 and an average of 0.56, which is quite good, considering that the two charts didn't have a full dry-down, and that my Isis is an old warhorse which has seen better days, and should probably be recalibrated.

  

As you can see the iPro2 handheld device does not have any tendency to operator-induced read errors, which were sometimes an issue with the old i1Pro. Also, using the new reading ruler to measure a chart is lengthy but it is not at all stressful. This is big progress compared to the old i1 which required quite a bit more patience, practice and elbow-grease. I've had some very pleasant experiences of late with the i1Pro when calibrating screens and am starting to appreciate this upgraded instrument and the new software. 

Edmund Ronald

BasicColor Click-and-get Giveaway.

BasicColor in Germany are a boutique color management company with high quality products. They are giving away stuff every day on a click-and-get basis. I think you might  as well go for it, it gets no cheaper than free ...

By the way, they are situated in the Paris timezone, called CET, which means UTC+1. 

Detaching the display shoe of the i1Pro2

As those of you with an i1Pro2 may have noticed, the display shoe is hard to remove, unless you know the trick. So here's the recipe for right-handers:

 Hold the unit in your left hand so the open sole faces you, with the heel on the right.

 Now make a claw with two fingers and hook them under the shoe fastening, and push your thumb through the hole in the sole.  Exert the detaching force by pressing against the spectro with your thumb. The two pieces will then easily separate.

Edmund

i1Pro2 Under the metal skin

I found some very nice cutaways of the new i1Pro2, and some more info. Couldn't resist sharing this with you'all :)

i1Pro2: Xrite's new heavy metal release

I just received and unboxed the new i1Pro2 Publish kit. The new spectro is as the saying goes new and much improved. I know it works because I used it to profile my laptop screen, but this kit can do a lot more, extensive testing will need time. Here are my initial impressions. 

Ten years after the original release, Xrite is giving the i1 spectro a major facelift. Originally a Swiss product designed at Gretag Macbeth, this lightweight handheld spectrophotometer has established itself as the go-to swiss-army-tool of every color specialist. It's an universal instrument as it measures both in emissive mode (displays, projectors) and in reflective mode (paper).  The i1Pro2 also acts as a dongle to unlock features in Xrite's software.

Xrite has gone from plastic to aluminium in a solid redesign of the venerable photo and prepress workhorse.  The added heft of the device is quite surprising. I'm told the metal in the casing should ensure better thermal dissipation, and hence more constancy in emissive reading mode. Thanks to some new UV diode technology, this new instrument replaces both the standard and UV-cut versions of the old EyeOne spectro.

Siblings

The old i1Pro warhorse did have some  ergonomic issues caused by its accessory shoes, which have now been addressed in the overhauled version. There is also a new optical sensor under the redesigned device, and some flashing LEDs —the white parentheses on top— to guide the operator when reading strips on paper. I shall talk about this in the print profiling part of this review.

Regarding the accessories, you can see in the first photo above how the new unit hangs suspended by its tail end on my laptop, in a much better profiling position than the old unit. Not only is the display mounting shoe much more user friendly, with a soft sandbag counterweight instead of the old metal gong, but there is now also a decent snap-reading shoe for spot mode. The white and black reference shoe has also been reworked, with the white tile kept out of harm's way by a retractable protective cover.

Finally, the  redesigned instrument,  improved paper reading tablet and all the new instrument holders have been nicely packaged in this James-Bondsy carry case.

From top to bottom, projector calibration base, and instrument clamp, display measure shoe, spot measure shoe, white tile shoe, i1Pro2 instrument. Facing side: Toy, Not for Sale.

Print profiling tray with new aluminium ruler, mini colorchecker and holey colorchecker. 

Holey Colorchecker 

The i1Pro2 Publish kit I got sent contains a mini colorchecker that can be used both as a screen reference and as a target for camera profiling, and a "holy colorchecker" for checking printer profiling.

I installed the new software, V1.3 form CD, and it immediately auto-updated to 1.3.1, with which I profiled my 17" MBP. The settings I employed were native luminance and native color temperature, and I quite like the resulting profile. So far, so good. More, shortly.

The swiss company Gretag Macbeth which designed the i1 had a reputation of gradually but thoroughly improving their products over the years, and the i1Pro2 is proof that this culture has been carried over after the various mergers which have taken place over the years. 

If you got this far, you're probably looking for my end of review freebie link. Today I leave you with some excellent display test images.  And a joke:  ROFLCOPTER.

Edmund

PatchTool Review PART I: From Target Image to CGATS file and vice versa.

Danny Pascale's PatchTool

Nutshell Review: If you need to hand-measure profiling targets or generate custom target grids, or wish to convert the patch layout output by one program to that needed by another, then you might do well to get a copy of PatchTool . But in addition to its invaluable patch conversion functions, this utility now also provides a sophisticated quality assurance toolset that can be employed for display, printer, and instrument verification.

PatchTool is one of those small specialized color utilities which can pay for themselves in a single hour of use, by quickly solving a problem that could otherwise be done by hand, were there but world enough and time. 

I'll talk about the simple and basic patch stuff today, the rest I will deal with in Part II of this review in a few days. Let me tell you about the simple tasks in which PatchTool can help a color consultant or color management expert, and why they're essential.

PatchTool's basic usage is the conversion of target images to CGATS files and vice versa, and also changing the layout of the image corresponding to a CGATS file. It can switch columns and rows, rearrange the array to a predetermined number of rows and columns,  etc, It can also acquire data from an EyeOne spectro to measure a set of patches and generate a file, thereby allowing for the creation of custom targets and Photoshop swatch sets,  and measure on-screen. All of this is useful to  color consultants and power-users:

Every user of color management software knows that to profile a device one must print or photograph a target. Then, the colors of the target are described in the computer by a so-called CGATS file. In fact, it is common to speak of the target's CGATS reference file, which describes known values supplied by a manufacturer,  and the corresponding CGATS measurement file which is written out by the user's instrument driver software. Of course a reference file, eg for a Colorchecker  chart can itself be viewed as a file written out by the chart-measuring technician of the manufacturer who supplied the chart. 

To a certain point, CGATS files are compatible between pieces of software, but as always the devil lurks in the details. One piece of software writes measurements of a grid row by row; then a profiling package by a different manufacturer expects its inputs column by column. What now? Well it's time to find some conversion helper.  Which is where PatchTool comes and solves the issue by reading the first file and spitting out another with the columns and rows flipped ! 

PatchTool is a an utility that is there to fix little annoying details, and what is impressive is that it really helps to gets all these little annoying details just right so you don't have to write custom scripts. In the image above you can see the options provided for writing values into a CGATS file, line by line — and of course if you read in a file, and spit it out with different options, you've done a conversion. 

Another typical use of this type of software for me is custom-measuring my ColorChecker and ColorChecker SG targets. I find that my own chart data —from my personal measured targets —deviate enough from the generic published images and reference files, that it is worth to measure my targets myself and create my own reference files for camera profiling, and before doing a chart-to-print comparison or even a chart-to-screen comparison. Here PatchTool can help out by driving a spectro and then spitting out a measured CGATS file, and even an image of the core of the measured target.What more could one wish for? Well, just maybe templates of the cardboard target borders to overlay, or even  comparison "holey" Photoshop layered templates …

This completes my quick description of the basic functions of PatchTool; it's not really an in-depth review because I've had a need, and used the software for two days, and it's done everything I needed without forcing me to pause and think. I'll have an exploratory look and address the "power user" stuff in the next installment. 

By the way, I like to leave my readers with a pointer to some useful net freebie as a reward for getting this far. Today's resource is Danny Pascale's fan page for the Xrite Colorchecker target, which has Colorchecker images in every possible colorspace.  Download one of these images, get out your physical target, and check out your printer and monitor profiles !

Edmund

i1DisplayPro - will Xrite move from proofing to viewing ?

Regarding hardware, the instrument is a strong followup to i1Display 2, Xrite says it is designed to be future-proofed for wide-gamut displays. I like the sexy design, and the fact that clipping it on a laptop screen really works. A carry pouch is just about the only improvement I could suggest for the hardware :)

Regarding software, i1Display Pro offers a hodgepodge of new features, which may or may not be useful, but at least Xrite is making an effort to explore the spectrum of functions that a colorimeter can fulfill. The old model was to view a calibrator as something to effect "dumb" calibration for proofing use with a D50 lightbooth in a "perfect" controlled environment. At some point we will have to decisively break away from this model, because it simply doesn't reflect the real-world everyday usage of computer displays which have become ubiquituous. 

Technology has evolved, I believe the high-contrast wide-gamut display IS the image now, rather than just a proofing device for pale yellowish paper. Files posted on the web are mostly clipped to sRGB, but when every display goes wide-gamut we will certainly expect to see more colors in every Facebook image of a rainbow.

Edmund

Cute, tiny Xrite Colorimeter released

Xrite has released the cute, tiny Xrite ColorMunki Display and i1 Display Pro; both are display profiling solutions that center around a very nice colorimeter  that looks like a toy searchlight:

In the above image, the ambient diffuser cover which can fit over the lens has been rotated down to act as a tabletop support for the unit, which can be aimed at a screen for projector profiling.

Fear not, the device fits very snugly even on a laptop display when hanging from its USB cord, I know because I was a beta-tester. The cord actually bears a sliding push-in adjustable counterweight aka retaining clip that hooks over the display edge, and works wonderfully on laptops. 

Depending on the version, the software for this unit has zilliions of new features, among which display uniformity testing, and building profiles that take ambient light levels and display flare into account. 

The gory details are all in the product brochure

Calibrating the MacBook Pro display

Under review.

How White LED display backlights work.

All the new Apple laptops are now using screens backlit by LEDs, I believe. These backlights do not involve red, green and blue diodes, but rather blue diodes encapsulated in a phosphor coated epoxy. This coating absorbs the diode's light and fluoresces, and reemits some of the blue light frequency-shifted to longer wavelengths by way of a physical phenomenon named the Stokes shift. Result, white light, or rather a weird but still smooth spectrum:

White LED technology is displacing CCFL (fluorescent light-tube) technology in laptops, and even in large TV displays; I guess the advantages are low-voltage power supply, no slow flicker and hum,The obvious disadvantage can be seen in the spectrum diagram above: The power output in the longer wavelengths is abysmally low, so you can expect to have a reduced gamut in the reds — no wonder then that demo discs for TV showrooms are heavily stacked toward Ridley Scott bluish decors. 

If your inner geek is still hungry Wikipedia is begging to illuminate. The graph above was excerpted from the linked article.

Bug of the day: Epson Premium Luster and Premium Glossy profiles

Every day brings its bug report. Today I noticed that the two Epson profiles "Epson Stylus Pro 3880_3885_3890 PremiumGlossyPhotoPaper.icc" and "Epson Stylus Pro 3880_3885_3890 PremiumLusterPhotoPaper.icc" installed by my Epson 3880 driver appear to be identical. 

I don't think those inkjet papers are anywhere identical, do you? I think this bug may be biting professional inkjet users, as I believe that the 3880, 7880 and 9880 use the same profiles. I found the bug by accident when comparing gamuts. 

Edmund

i1Profiler - Xrite pimps new software with innovative interface

 

I received the i1Profiler upgrade for my purple PMP dongle a few weeks ago, and have now played around a bit with the product. Xite support helped me quickly and effectively with some minor installation woes, when i1Profiler had a conflict with the installed ColorMunki software. I then ran a single-page target on the iSis to create a profile for my Epson 3880, on some old experimental Canon matte paper, and this profile was first rate.  Every other color geek seems to like the profiles too, although some deplore the absence of direct DTP-70 support (measurement files are accepted) and the fact that scanner profiling has been dropped.

 i1Profiler does display, projector and both RGB and CMYK printer profiles. It updates most of the features of old Monaco and PMP (see below), and wraps them in a very pretty but also truly innovative interface. This has a basic mode with plenty of online help for the non-specialist and a truly novel advanced mode for the color geeks. The innovation stems from the way in which it s possible to save settings or measured data - the saved states are symbolized by icons and called assets and workflows.  It's like nothing I've ever seen before, which is why I'm simply pointing you at the video. I think this interface is so interesting that people will copy it. 

 This blog has had a hiatus for a few years, but in that time, nothing really changed in the color world. Gretag got merged into Xrite, but the combined company marketed both Xrite's Profile Maker Platinum and Gretag's Profiler Maker Pro professional publishing software, and the prosumer i1Match series. All of which were visibly stuck in a minimum-maintenance mode.  They will now be retired as i1Profiler addresses both pro and prosumer in a very complete  one-size-fits-all package; most users will be quoted around $500 list for the upgrade, although there seem to be some better deals floating round.

 Prosumer sales and upgrades from i1Match will take off right now, but it may take more time until the prudent and conservative pro color community fully adopts i1Profiler, since many users are still quite happy with their existing packages. However, I do think Xrite has a solid winner here, and the release of 1Profiler demonstrates that the company has fully digested the merger and the Pantone acquisition, and can now move ahead again with product development.

 I'll come back with a more detailed look at some of the i1Profiler features, reasonably soon.

Edmund Ronald

Tandem Workflow in Photoshop

I guess I need to spell things out in detail for the Adobe crowd. In Photoshop ACR, the tandem Raw profile workflow could be implemented with the DNG matrix transformations as the faithful calibration profile, and something akin to a "Raw adjustment layer" as the digital emulsion.

The essential feature is that the effect of both the camera calibration and the emulsion be previewed when the user twiddles the Raw sliders eg. exposure.

Edmund

Photography is NOT reprography: Raw workflow needs tandem profiles.

Photography is not Reprography.

Dual ICC profiles as faithful and creative enablers for the Raw camera workflow.

I believe dual ICC profiles, working in tandem, are required for a creative Raw conversion workflow. The first profile is needed to define the colorimetric properties of the camera, the second to describe the operator's chosen exposure curve compression, color adjustments and other esthetic effects.

Photography is not reprography. Cameras are creative tools with which by pro photographers have historically used emulsions to create imagery; with respect to what an eye on location would see, the resulting individual images recorded on a chemical emulsion are often far from colorimetrically correct in any sense, even less so when lens filters or light gels are used creatively rather than for correction.

However existing digital ICC input profile workflows inherited from scanner days are historically designed to channel data with some degree of colorimetric correctness. To summarize, the scanned film workflow translates into accurately digitally reproducing the wildly inaccurate colors of an image chemically imprinted on the film.

In the digital playpen, photographers again expect to play with new digital versions of their old deliberately inaccurate creative tools. And the right moment for creative tone curve, color hue and exposure tuning is really during Raw conversion. Coincidentally, Raw conversion is also the moment where colorimetric accuracy is best established. Which is why we expect ICC profiles to find their use in dual ways during Raw conversion. And if the use is dual, two profiles should be applied.

Separating the Raw digital camera profile in two stages, one devoted to calibration —sensor and lighting characterisation— and one devoted to the "film look" would enable a more intuitive workflow. Essentially we argue that the creative steps can and should be follow the somewhat faithful ones, but both can be represented by ICC profiles.

The first profile, the calibration profile, is a standard ICC input profile which characterizes the camera and and Raw converter. The second which applies the look might be called a "digital emulsion". It can be realized by means of an abstract ICC profile. There is no need for the digital emulsion to be colorimetrically accurate in any sense - an emulsion may even emulate black and white film !

What software changes are needed for the tandem-profile workflow ? Clearly, new Raw conversion tools tools must allow both "calibration" and "look" profiles to be selected, and their superposed effect visualized. Present-day camera profiling tools are already adequate for the creation of the "calibration" profiles. Ideally however, a profile editor would allow the user to cook up "digital emulsions" on the fly so that they can then be applied to batches of images, even across camera brands.

Edmund Ronald.

Canon 5D Portrait Profiles for Capture One Available

Canon 5D Portrait Profiles for Capture One Available

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My 5D Portrait Profiles for Capture One are now available. Send me an email and I will send them out to you.

edmundronald at gmail dot com

Edmund

5 Ways to mess up profiling testcharts

5 Ways to mess up profiling testcharts - sung to the tune of "Mission Accomplished".

1. Client has a color un-manageable PS/Mac-OS/Epson system.
Yes, Adobe, Apple and Epson finger-point at each other, it's always the other guy who implemented wrong. Let's hope your client is lucky enough to have a system which works. Yeah, right.

2. Client prints with some color management still enabled in the print path.
There should be a big button which says "Profile Testchart" in both PS and printer drivers. But there isn't. Instead the printer driver has a bunch of buttons labelled "Hurt Me". Thanks for pointing out that label, Andrew.

3. Client has a corrupted Epson driver.
Epson drivers seem to suffer bit-rot. Clients are always astonished how different their charts look after the print system is reset. Well, if they can notice that, at least these clients won't blame you for the first bunch of bad profiles you sent them.

4. Client resizes the print chart.
Clients don't know we have position-absolute auto scanners. They think we have a cage full of monkeys with 1mm aperture EyeOnes who read the charts, whatever their size. Maybe we should print "Do not Resize" on each chart.

5. Client's native RIP messes up patches.
Some print drivers try to be smart when they uprez to printer resolution, and mess up the patches. The solution is to have your client uprez himself with 'nearest neighbor" interpolation. But this should be implemented as an option in the driver.

Last and best. Client sends in testchart festooned with glue-on labels, adhesive tape.
Yes, kindergarten kids do so love office supplies.

Gentle reader, if you happen to be working for Apple, Adobe or Epson, maybe you could do something to help our and your clients avoid these built-in wolf-traps ? Maybe disarm them ?

Edmund

Camera Profiles as Raw Emulsions

Camera Profiles are the film emulsions of the new Raw Workflow.

As a photographer, I have a set of "signature looks", which I choose to stamp on my work. These looks define my own way of rendering the world of color.

Also, in this new digital world, can package my "color vision" in a profile and share my "look" with other users. This is like cooking up an emulsion and selling film boxes. My experience with the my heavily edited Leica M8 portrait profiles has been a definite success in this regard. As they say, payment is the most acceptable form of flattery ...

I find that camera profiles as exploited in Capture One and Raw Developer are an easier way to stamp my look on a bundle of files than the Lightroom/PS curves approach. Let's compare workflows and we'll see why:

- In C1/PS:
I load my image and set my *signature camera profile*. This overlays my "signature look" on the screen preview. Now, I can twiddle the twiddle the C1 expsoure controls to my heart's content, but *signature look* is already embedded in the image. It's as if I had loaded a preset emulsion in my digital camera. And I haven't yet even opened PS !!!!


- In ACR/PS:
I take a Raw image. Open with ACR. Twiddle the ACR sliders. Get it roughly right. Then move to PS, apply curves etc. Now only can I see my final image *with my signature curves*. Of course a skilled retoucher will work mentally towards this target, but the target "color look" is only fully visible after the last curve is applied in Photoshop. Oh, and by the way, I love curves, and I hate those zillions of sliders in ACR, Lightroom and Aperture!

We see that the Capture One/Photoshop combo and the Lightroom/ACR/Photoshop solution work up differently although they should reach the same image quality.

My opinion in a nutshell: Camera profiles can and should take the place of film emulsions in the new world of Raw, and their use should be integrated in all Raw processing software. Conversely, the current Adobe approach to Raw suffers gravely from general kludginess and an excess of sliders. More controls do not a more intuitive interface make.

Edmund

PS. A debate with Andrew Rodney on the LL forum allowed me to formulate my position more clearly. I would like to recommend Andrew's excellent tutorial book to all my readers who wrestle with the practicalities of color management.

iSis review coming.

I now have a new Xrite iSis XL, and preliminary tests indicate that it's working great ! My previous sample of this instrument was transport damaged, which is why I didn't talk about it a lot.

The iSis is a very modern scanning spectro, based on an EyeOne diffraction grid head, which is replacing the Xrite DTP70.

Amongst the new iSis features: Solid-state illuminant, chart readings with and without UV, and a machine-vision sensor that can read bar-charts and identify the chart.

In addition, the XL model has a wider "carriage" and can read A3 format charts.

I'm using this instrument with Monaco Profiler mainly, via the new ColorPort 1.5 utility that Xrite should by now have available for general download. I shall be describing the iSis more in detail soon.

Edmund

iSis - Release transport catch before use

I visited Regensdorf today and the nice people at Xrite ex Gretag swapped my transport-damaged iSis for a new one. And warned me to look at the QuickStart Guide:

There's now a head-lock catch on the under-side the iSis, which should be moved to the unlocked position before use. This catch is much nicer than the slip-in plastic head-guard which was included with the first iSis unit I was sent.

Before transporting the spectro again you're supposed to move the catch back to the locked position, open the device and sweep the head to the right until the head engages.

Edmund