Using a smartphone as a loupe

Part of my work as a prepress operator requires looking at printed material under magnification, usually a loupe. This is done for a variety of reasons, such as:

  • Determining if a previous print was printed in full colour process or spot colour;
  • Assessing the effectiveness of trapping;
  • Checking if print is aligned in register;
  • Determining the dot structure of a printed product (was it stochastic or halftone; and if it was halftone, was the dot shape round, Euclidean or other);
  • Attempting to determine the value of a colour breakdown;
  • Confirming that barcode width reduction appropriately compensates for ink gain on a printed barcode.

In previous posts on Colecandoo, I’ve shown several photos taken using my digital microscope, such as this image that was used to illustrate the misregistration of a varnish compared to the ink underneath.

The digital microscope is certainly useful for checking details not immediately obvious with a loupe such as the barcode example, but for most magnifying tasks, a loupe works just fine.

Isn’t there a smartphone app for this?  

Yes and no. There are specific smartphone apps I will use for prepress work, such as:

  • What the Font – great for identifying fonts when I’m far away from my laptop;
  • Measure – when a tape measure is unavailable and centimetre precision will do;
  • Adobe Scan – when I need to take in typeset material when I’m not near my flatbed scanner; or if a customer’s original can’t be taken apart to fit on a flatbed scanner.
  • Touch Portal – when I need extra buttons for my laptop – an equivalent would be elgato’ streamdeck.

Many smartphones now feature macro lenses that have comparable zoom to a loupe, but require the phone to be held the correct distance away from the subject and to have a steady hand or a rig established for the purpose.

Enter smartphone lenses

I’ve recently invested in a macro lens for my smartphone. Since using it at work, it has been quite useful – to the point where it inspired this article.

To demonstrate the difference of the smartphone macro lens to the default macro lens and the digital microscope, here is a comparison on a printed image.

For me at least, I can now safely stash my old loupe in the desk drawer and begin to use the macro lens as an alternative. Here are some reasons that I’ve made this decision:

It has several advantages over a conventional loupe:

  • Virtually no chromatic aberration
  • Others can see the image without me needing to share the loupe
  • Can share the footage live using screen sharing software so that the image isn’t just on the phone screen, but on a larger display; or take a photo and email to the client or file for later use.

There are also several advantages of this lens over iphone’s macro lens:

  • Higher magnification;
  • Stable to hold as the diffusion filter also acts as a rest;
  • As any Sandmarc lens is shipped with a case or clip to allow the lens to be mounted, it also provides the ability to change out lenses for other purposes

This also has advantage over the digital microscope

  • No wires;
  • Requires no additional power;
  • No additional “unitasker” software (serves one purpose alone)

However, the macro lens isn’t without it’s disadvantages:

  • Needs good lighting – a backlight would help tremendously;
  • Requires a case or clamp to fasten the lens, though with the Sandmarc lens that I purchased, this was provided upon purchase;
  • Requires additional software to access the individual lenses as the iphone’s default camera app will not allow this flexibility – software such as Adobe Lightroom is what I use, but this was on my phone anyway;
  • Not portable enough to become part of my everyday carryables such as car keys, phone, wallet etc. Is small enough to fit in a tiny bag that sits on my desk.

So while I now have a new tool in my prepress arsenal, I’d like to know what other apps or tools that people are using to assist them in their design or prepress tasks – feel free to comment below.

Finally, as a matter of full disclosure, this article is NOT sponsored by Adobe, Sandmarc, Apple or any other company mentioned in the article. If they would like to sponsor Colecandoo in the future, that may be something to explore, but this article is my own thoughts and opinions and the macro lens I purchased.

Enfocus Pitstop Pro users: uncheck this item in Acrobat

In trade school, one tip the lecturers always pushed was to never update to the latest software version straight away, but let others experience the problems first, then upgrade once the first patch became available.

This lesson was further reinforced this week when I received an email from Enfocus – the manufacturer of the Pitstop Professional plug-in for Adobe Acrobat.

Unfortunately for many Adobe Acrobat users, the software had already updated – usually without the operator’s knowledge – until the signs of problems presented themselves, and by then it was too late.

In my case, updating Acrobat is something I have to do manually, having learned the hard way what can happen when software – used in a production environment – is changed without warning and affects components of production. I did this by going to Acrobat’s preferences, navigating to updates, and unchecking the dialog box that says Automatically install updates.

What confuses matters is that Acrobat is considered part of Adobe’s Document Cloud more than it is in Adobe’s Creative Cloud – something that can be demonstrated by going into the Creative Cloud application looking at the items installed… or could simply be an unreported bug. In the following screenshot, it appears that my version is already updated.

But unlike the InDesign install that shows the version number, Acrobat DC’s version number isn’t displayed, so instead I choose to check for updates manually.

I’m now presented with a new dialog box that informs me that an update is available and if I would like to install it now. I decline and press the No button.

Unfortunately, my colleagues were not so lucky. I was originally aware that an update to Acrobat was available via Adobe’s replies to my earlier posts in the Acrobat.Uservoice.

Instead, I was fielding questions from my colleagues concerning a previously unseen bug in Acrobat concerning “why can’t I see what I’ve selected?”.

The issue that is caused for Mac users

The fault concerns the Enfocus Pitstop Pro plugin for Adobe Acrobat on Mac only in the 21.007.20091 install; and has to do with items selected using Enfocus’ select tool are not highlighted (see this link for Enfocus’ own description). In the following example, the text in the left hand column has been selected using the pre-patch version.

And here is how the same selection appears in the 21.007.20091 version.

It isn’t a catastrophic failure of the software, but it’s certainly frustrating and will make tasks much harder for operators until this issue is resolved.

So who fixes this?

Another lesson I’m still yet to fully appreciate is not to post bug reports to social media sites such as Twitter, like I did in this instance. I’d posted to both Enfocus and Adobe Acrobat in case neither team knew of the issue.

To the Acrobat team’s credit, the response was within five minutes of the tweet, though the next few tweets were trying to act as support. It’s just an educated guess here, but it is my belief that the social media team who manage these posts don’t actually use the software, and that’s fine – I’m simply reporting the issue and not trying to troubleshoot the issue over Twitter.

In Enfocus’ email from Andrew Bailes-Collins, the Senior Product Manager, he states “We have reported the issue to Adobe, and are in discussion with their engineers on how to resolve the issue. Please be assured that we will resolve this issue as soon as possible. When there is a fix, we will let you know via email.”

What now?

This post isn’t to point criticism at either Enfocus or Adobe as I’m aware that not everything can be tested during software development. I too am a software developer and from time to time have had to change or modify scripts on Colecandoo due to a change in how Adobe InDesign now works with the scripts I’ve written. Similarly, I test as much as I can, but have had issues with some scripts such as “It doesn’t work in my language version of InDesign”.

What I would find beneficial would be for the Acrobat team to change the updating preferences in Acrobat to be an “opt-in” rather than an “opt-out”; and to also integrate the Acrobat DC updating into Creative Cloud so that the version number can be seen; and that Creative Cloud can alert to the updates, rather than happening automatically or having to manually check from time to time. What would also be handy is the ability to roll-back to the pre-patch version – something that we have been unable to do in this instance.

Intolerant about tolerances

Designing print projects on-screen comes with a false sense of precision. It is easy to assume that whatever is designed on-screen will accurately reproduce – without flaws – into a real-world finished product. This is reinforced by the ability to place objects on precise coordinates and align and distribute with similar precision.

Unfortunately, the practical application of the design from computer to real world product comes with a series of tolerances that are not taken into account in the design software.

Such examples are

  • Variables in the substrate. Paper stocks can stretch, distort and swell based on humidity, storage conditions, temperature and ink density, just to name some variables.
  • Creep (aka shingling, pushout or thrust). This is covered in an earlier article, but it is the phenomenon of artwork in a book moving towards the foredges of pages due to the gathering of folded sections.
  • Registration between inks and Embellishments.
  • Precision of the paper folding.
  • What your computer says vs what the output device prepares.

Some tolerances are hardly noticeable and imperceptible without magnification, while other tolerances are large in comparison. This article will examine several print phenomenon and the tolerances associated with each phenomenon.

Tolerances in ink registration

This is an example where tolerances are quite tight, and best shown when printing several colours in one pass, such as full colour process offset printing, digital toner or inkjet printing. Take for example the following headline.

At normal magnification, the inks appear to be in perfect registration. However, when zoomed in, it is possible to see that the registration of the inks is slightly off, demonstrating tolerances in microns.

However, it doesn’t take much to make the tolerances worse, such as:

  • Using a printing method where misregistration is a larger concern, such as flexography or screen printing;
  • Printing additional colours on a second pass, meaning the sheets have to dry first and add the variable of paper distortion to trying to register the additional inks to the previously printed inks.

Embellishment registration

From here, tolerances begin to get worse. Take for example a full colour plus one spot colour print that has an additional spot UV clear varnish applied over the lettering.

Note that while the inks are in register, the spot UV is off by half a millimetre to the top right. This is because two separate processes were used – a five colour press to print the inks onto the paper; then the spot UV was applied using a screen printed stencil that was made using an imagesetter that was different to the platesetter that produced the images for the plates.

Another example is how a design translates from screen to embellishment. Take this complicated foil, and notice how the fine detail in the foil is lost.

Fold registration

This is where tolerances can be out by several millimetres. A simple exercise that demonstrates this issue is to take a sheet of paper and fold it in half four times, then look at how the pages line up at the heads and feet of the folded pages. The same issue occurs when taking an imposed sheet and folding it into a signature to combine with other gathered signatures for burst binding.

Take the following example that has a running header in InDesign where the sidebars bleed off of the foredge. Note the difference between the highest point vs the lowest point.

What can be done?

  • Know that printing and binding are not precise and subject to tolerances like any other manufacturing. What is important to know is where the extreme tolerances lie and how to design with them in mind.
  • Speak to your printer or finisher and ask to see samples of previous work.

There is also page to page registration that needs to be discussed, but this will be covered in a future Colecandoo article.

Inklude (sic) Mixed Inks into Illustrator

A feature which is strangely absent from Adobe Illustrator (yet present in Adobe InDesign) is mixed inks. This gives the user the ability to make a new swatch based on percentiles of other swatches that can include spot colors, along with process colors.

InDesign’s mixed ink feature also allows groups of mixed ink colors to be made, based on how much of each ink should be in each swatch, and the increments they should differ by.

For pure spot color work, this can create colors that would otherwise require using blend modes such as multiply or darken to create similar colors. However, from a prepress standpoint, mixed inks have several advantages over applying blend modes to objects to achieve the same effect.

Embellishments

For digital devices that can apply inline varnishes, mixed inks make sense. In the following example, the headline requires a varnish

Usual way of doing this would be to create a second layer with an identical headline, but set to a Varnish spot color on another layer, with either a transparency effect such as darken or multiply applied; or overprint turned on from the attributes menu.

That’s fine if the position of the artwork is final, but if the design is in a state of flux, that requires moving the varnish to be in the same position as the type.

A solution is to use InDesign’s mixed ink to create a new mixed ink swatch. In this case, I’ll call it Varnished Headline, and give it 100% of the black and 100% of the varnish spot

This solution also applies to other common embellishments such as embosses, foils, raised varnishes, etc.

White Masks

When preparing label artwork for clear or metallic substrates, white masks have to be prepared so that the color art can appear correctly above the substrate. Take for example this logo to be printed over a silver background.

Again, by using mixed inks, it is possible to make a white mask that doesn’t require another layer, blend mode, and can move with the artwork. In this example, three colors would be created: the white mask; Red and a white mask; and Black and a white mask – the last two being mixed inks.

The art can then be recolored so that the red now uses the red mixed ink; the black now uses the black mixed ink; and the paper now uses the white mask ink.

Notice that the gold cup does not contain a white mask – that is because the gold color – when printed on a silver stock – will appear more like a gold foil.

Double-Hit Prints

On one or two spot colour jobs that have large areas of solid ink coverage, occasionally the same colour will be applied twice on the press as to hide any mechanical ghosting from the printing process.

In the above example, one plate would be for the solid color, and a second – though stippled plate – would be for the undercolor to hide the mechanical ghosting. This color can be set up using InDesign’s mixed inks.

But this is missing from Illustrator!

Despite the mixed ink feature being available in Adobe InDesign, it is notably absent from Adobe Illustrator. This is frustrating as artwork that usually requires the three solutions above is often prepared as Adobe Illustrator artwork, requiring old-school solution of layers and blend modes.

If you feel that this missing feature deserves to be in Adobe Illustrator, make sure to let the Illustrator Uservoice know!

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