Posts Tagged ‘color difference’

Same Run? Different Color?

July 18, 2019


Top photo. Look carefully. You are looking at the start of a printing run on two separate bolts of paper. On the bolt to the left, the color looks pretty uniform.

But on the bolt to the right, you can see a horizontal line where the background has been colored. It’s faint, so look closely. In addition, you can definitely see that the paper on the right is darker than the paper on the left.

If there were more fish present, you would also see that on the right, the greys are a little darker and the reds are a little stronger. There are also more brown speckles in the background of the grasscloth on the right.

What happened was, too little paper was ordered (a simple mix-up between rolls and yards), and so more had to be ordered, and then custom-printed.

The interior designer stressed to the manufacturer that the new paper had to be the same run number (all bolts printed at the same time out of the same batch of ink). The manufacturer’s reply was that their precision printing and ink-mixing was such that there would be virtually no difference in color between what we had already, and what they would print fresh and send to us.

As you can see, that is not the case. Although these differences are minor, if strips from these two bolts were placed next to one another on the wall, the color difference would be pretty noticeable.

So, accommodating for this color difference, we lost about three yards of (expensive) wallpaper.

Run Numbers Are Important

April 14, 2019


I hung two wallpapers today, both from Anthropologie, and in both cases, the homeowner measured and purchased paper before I had measured and figured how much to buy. In both cases, they were a double roll short. I told them that when they ordered the extra double roll, to be sure to ask for the same run number as the rolls they already had.

Unfortunately, in both instances, Anthropologie sent a different run. Probably, the guy in the warehouse didn’t get the message from the people in the order department, so he just pulled any old bolt of paper off the shelf.

Run numbers DO make a difference. As you can see in the second photo, the butterflies are clearly different colors. And in the third photo, the color difference (red flower, brown leaf) is less dramatic, but still noticeable. The white background is probably a slightly different color, too. If these strips were placed next to each other on the same wall, you would notice an abrupt color difference the full height of the wall.

So it’s important to make sure that all your bolts of wallpaper are of the same run number.

Run number, also called batch number or dye lot, refers to rolls that were all printed at the same time. The next time the manufacturer is ready to print up that pattern, he will mix up a new batch of ink – but that batch might be a slightly different shade than what was printed previously.

Because these color differences will be noticeable on the wall, it’s important that they not be used next to each other. You can use different runs on separate walls, but not on the same wall. If you are forced to use broken runs, as they are called, you’ll need to buy a little extra paper, because there will be more waste as you switch from one run to the other.

Different Runs

February 8, 2019


Look at the center of the photo. See that slight color difference between the strip on the left and the strip on the right? This is most likely due to the two strips coming from two different run numbers. These can also be called batch numbers or dye lots.

This means that all paper that is printed from one batch of ink is given a run number. Three months later, when the manufacturer is ready to print another lot of wallpaper, a new pot of ink is mixed up. Chances are that that new kettle of ink won’t be exactly-dactly the very same shade as what was used previously.

This means that the two batches of wallpaper will be ever so slightly different in color. If strips of paper from the two different runs are put on the wall next to each other, you will notice the color difference. So each batch of ink, and the paper that is printed with it, is given a run number.

That way, the installer can be sure that all the wallpaper for his job will be printed at the same time, of the same run number, and all the same shade.

Checking for run number is the first thing every installer should do, before starting to hang wallpaper. In fact, in my “how to prepare for install day” info pack, I ask my clients to check to be sure all bolts are of the same run number. That way, if there is a problem, there will be time to return the bolts and get new paper that is all of the same dye lot.

If you end up with a broken run (two or more different run numbers), it is possible to use the paper, but you have to keep the different runs on separate walls… your eye will not notice a subtle color difference if the papers are on different walls. But this uses up a lot more paper.

Stretching the Paper to Avoid a Pattern Mismatch / Color Shading in Grasscloth

October 28, 2018


Two things about this photo. First, you can easily see the color difference between the narrow panel on the left, and the one to its right. You can also see that the color of the grasscloth darkens 2/3 of the way down the middle strip.

This variation in color is normal – even expected – in grasscloth, and is called “shading,” or “paneling.” It’s referred to as the “inherent beauty of this natural product.” But, personally, I don’t care for it.

Read my informative page to the right, to learn more about grasscloth.

Another thing to note … this corner is the last corner in the room to be papered. Virtually always, this last corner ends in a pattern mis-match – which can jar the eyes. So I placed it up over the door, in the least conspicuous space I could find.

Indeed, since the distance between the motif on the final strip did not sync with that on the first strip, the pattern was going to end up with a floral stem being split in the corner, leaving half of the greenery visible and half cut off. I didn’t want any cut off flower stems.

So I “grew” the paper. The distance between the flowers was supposed to be 5″. I used some scraps of paper to cut a strip 3.5″ wide, and another 4″ wide. This gave me an expansion of 7.5″ – wide enough to bridge the final distance without cutting off any flowers, but not wide enough for the eye to detect that the spacing was not exactly as the artist originally plotted.

The pattern is “Acanthus” and the manufacturer is Schumacher.

Slight Color Difference

June 4, 2018


Look closely, just to the left of center, and you will see that the strip on the left is slightly darker than the strip on the right. This is called shading, and is because, in this case, the left side of the wallpaper is a slightly darker color than the right side. Therefore, when two strips of paper are butted against each other, the difference in color can be seen.

In this powder / laundry room, with poor lighting and a busy pattern and a relatively mild case of shading, I didn’t consider it bad enough to halt the job and reorder more paper, and so I went ahead and hung the room.

Everyone loves the finished room.

I am probably the only one who can spot this minor color difference.

Run Numbers Running Wild – Not Acceptable

April 4, 2018


For this job, the vendor sent FOUR different run numbers, plus two bolts that had no run numbers at all. It all had to be sent back and exchanged for new paper – all in the same run, please!

Run numbers are very important. When wallpaper is printed, each batch is marked with a run number. The next time the manufacturer makes a batch of wallpaper, a new vat of ink will be mixed up, and it will be an ever-so-slightly different shade from that which was used before. So that new batch of wallpaper will be given a new run number.

These color differences are minor – but if they are placed next to each other on a wall, you will have a very noticeable color change from one strip to the next. In the second photo, you can probably see the difference in color between the red flowers, and maybe even the green and brown foliage.

In the third photo, a smaller rectangle of the wallpaper pattern has been placed on top of a larger rectangle. All around the perimeter, you can see a slight color difference between the reds, greens, nad browns.

But it’s important to realize that the background will also be of a slightly different shade.

When two strips of two different runs are placed next to one another on a wall, the shade difference will be obvious in the form of a floor-to-ceiling slight-but-noticeable color difference. https://wallpaperlady.wordpress.com/2016/07/19/two-runs-are-not-fun/

It’s possible to work with this, by “breaking” the runs in a corner. But this uses up a lot more paper, and it’s too complicated to explain here.

This wallpaper was bought from an on-line mass-marketer. I like the quality of their products. But they seem to have no clue of how wallpaper works, and the customer service person had no grasp of what a run number was or why it mattered. From a vendor like this, you can pretty much expect that they have a bunch of stock shoved into shelves in the warehouse, and when someone buys some, a worker just goes out and pulls any old rolls from the stack, willy-nilly, with no regard to run number, damaged goods, and may not even check to ensure they are all the same product number – A coupla months ago, I got the same pattern but in two different colorways.

The bottom line is, buy your paper from a reputable source, check the run numbers when the paper arrives, and, if necessary, keep separate runs on separate walls.

Color Difference Due To Fading Over The Years

January 24, 2018


I hung this original paper more than 15 years ago. Some areas had become stained, so I was called to fix it. Luckily, the homeowner had saved the left over paper, so there was enough to replace the damaged strips.

You can see a slight difference in color between the strip on the left, which was hung 15 years ago and has been exposed to light all that time, and the strip on the right, which has been stored in a dark closet until I put it up today.

Two Runs? Three Runs? Either One Is A Bad Deal

January 1, 2018


The client bought her paper on-line, before I saw the job and measured the space. Like most homeowners, she ordered too little paper. I told her to get another double roll.

The new roll was a different run number. In the photo, you see one is Batch 15, and one is Batch 16. And the label on the third double roll has been removed and discarded, so we have no way of knowing what batch that one is.

The problem is that each batch of wallpaper that gets printed will be ever so slightly a different color from every other batch. Not a problem if you can keep the different runs (batches) on separate walls. But if you have to put strips from different runs next to each other on the same wall, which is 95% of the time, you are likely to see a slight difference in color. This will make your wall look like it’s striped. Not good.

Buying wallpaper on-line can be cheaper and fast, but since people at the company are order-takers and are not wallpaper-savvy, there is noone checking things like run numbers. This is why I encourage clients to buy locally.

In my “Where To Buy Wallpaper” link on the right side of this page, I name several places where people really understand wallpaper, and so you can shop without having to worry about issues like run numbers.

Two Runs Are Not Fun

July 19, 2016
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When I first consulted with this client, she had already bought some wallpaper – but she did not have enough to cover her wall. (Note to homeowners – always have the space measured by a professional before you order your paper.) So she ordered more – but the new paper that arrived was from a run different from what she already had.

“Run” or “batch” numbers refer to when a batch of wallpaper was printed. Wallpaper printed at different times, and of different runs, will be slightly different in color.

This slight color difference is what you see in the second photo, the thin strip at the left of the pic. Even if the difference is minute, full length strips side-by-side on the same wall can be quite noticeable.

So, if you find yourself stuck with having to use different runs of wallpaper, you can disguise the color difference by “breaking” the runs in a corner…Because light hits the walls differently from one wall to the next, you won’t notice a slight color difference when the two different runs are on two different walls. However, it takes a bit more paper to do this. So, if you are dealing with two different runs, be sure to order one or two extra double-rolls of paper.

Same Grasscloth; Different Colors

November 15, 2015
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The grasscloth on the right was bought a year or so ago. It was left over and the homeowners wanted to use it on a new project. They needed additional paper to do the space, and so ordered a new bolt of paper. As you can see, there is a noticeable difference in color and texture between the two bolts, manufactured at different times. This is known as “run number” or “dye lot.”

It is also called “shading” and “paneling,” which refers to the difference in color between strips on the same wall. I had enough paper to cut all my strips from the new bolt, so there was minimal color difference on this project.