laser engraving machine

How to Prepare Your Image for Laser Engraving

If you’ve never used a laser engraver before, you might be surprised at what can happen when you finally get into the workshop and start your own machining process. Laser engraving is a versatile application – it can be used to mark medical equipment or aftermarket auto parts that can withstand the harshest conditions, or to commemorate a birthday or special event by marking the date on a souvenir.

One of the coolest applications for atomstack laser engravers we’ve seen is working with photorealistic photos and images. Our galvo laser systems are so precise that in addition to engraving words and phrases, you can actually engrave photorealistic images into stainless steel. You have to be comfortable with grayscale, but when you get your images set up correctly, this incredible process produces great results.

atomstack s20 pro laser engraver

Based on our own trial and error process, we have come up with the ideal step-by-step process for preparing your chosen laser engraving image. With so many different types of laser engravers available, and so many software options for preparing images, it’s hard to generalize about a one-size-fits-all approach, but we’ve done our best to make this guide accessible to everyone. Whether you’re an experienced designer working with Corel DRAW or the free online tool GIMP, follow these steps to prepare your images for sculpting.

atomstack x20 pro

Step 1 – Start with a high-quality image
When choosing an image for laser engraving, it is important to start with a high-resolution, high-quality image. A stamp image scanned from an old photo album will not retain its sharpness through the transformation that occurs before the image is ready for engraving, and you will not be able to ”inflate” or ”zoom in” like a picture from a CSI TV show. Make sure to use it well camera to take high-resolution photos for the best results.

Step 2 – Cut to Perfection
The advantage of starting with a high-quality photo is that you can effectively crop it and make it look bad. Cut out the parts of the image that you don’t want, and resize the rest to the size you want it to appear on the stainless steel or other material you’re using.

Step 3 – Remove the Background
This step is important and may require using the clipping tool in your image processing software or some handy Photoshop skills. If you don’t remove the background, your image may get lost in the background during the engraving process. By making the background of the image pure white and the laser engraving only the object in focus, you can avoid obscuring objects with irrelevant background details you don’t want.

atomstack a5 20w

Step 4 – Convert the Image to Grayscale
Laser engraving naturally produces grayscale images by cutting different lines at different depths for different number of passes. Generating an image in grayscale gives you a good idea of ​​what it will look like when sculpted onto the material of your choice – your image is almost ready! Looking at the grayscale image should help you with the next steps, you’ll have to make some slight edits to the image for best results.

Step 5 – Edit your photo however you choose
Now that we’re working on something similar to what a laser engraver will produce, we can start making any version that’s important to achieve the desired result. Editing photos is a highly subjective process, but we’ll offer some advice. These can be applied to photos of people, places or objects.

You want to try to maximize contrast in key areas of your photo. This usually means making whites whiter and dark areas darker.
Areas that appear white in real life, such as eyes or nails, should be highlighted in the image by reducing any shadows that appear there. Set the black to 3-6% to help these areas stand out better.

Remove shadows from any faces in the image, as the dark contrasts too strongly with hair, which is usually darker. Set black to 10-15% for best results.
For dark tresses, darken them. For lighter tresses, you can make them lighter.

atomstack a5 pro

Step 5 Alternative – Color Index
If you’re not going to edit your photos, there’s an option you can choose to help maximize contrast without having to make any complicated changes yourself – that tool is Color Index. If you plan to use color indexing, you may need to do this before changing the image to grayscale.

A color index is a tool that some imaging software has that repaints your photo with a fixed number of colors for maximum contrast. It essentially looks at all the colors in the image, combines them into any number of groups of your choice, and replaces each group with one color. All you need to do is choose the number of colors you want for the image and let the image processor do the rest.

Step 6 – Sharpen Your Image
Sharpening just makes lines look thicker, and it’s a simple tool that exists in almost every photo editing program. For photos of people, sharpen the eyelashes, lips, hair around the face, and any other areas you want to emphasize in the final sculpted image. If you photographed objects or buildings, focus on the most important lines that add texture to the image and give it a three-dimensional feel.

Step 7 – Convert and Export
Your image should now look the way you want it to be sculpted on stainless steel, plywood, or other materials. The next step is to convert this image to a bitmap of the appropriate resolution and transfer it to laser CAD software for engraving. When exporting as a bitmap, the recommended resolution is approximately 200 pixels per centimeter. This ensures that your images are displayed in high resolution on the material of your choice.

atomstack s10 pro

Step 8 – Press the red button
The last and most fun step is always setting the options on the laser cutter and pressing ”start” at the end after all the hard work is done. Engraving differs from laser etching in that it makes deeper cuts in the material, and it’s usually better to program the laser to make multiple passes over the material, rather than trying to blast a large piece of steel or wood in a single pass. Our galvo lasers use an oscillating mirror system to cut at extremely high speeds, so your project will be complete in minutes.

in conclusion
Just follow these simple steps and you can reproduce images of stunning quality on a piece of stainless steel, birch or laminate. You also don’t have to be a graphical wizard — in fact, it doesn’t matter what program you use, as long as it performs the basic functions we’ve outlined above. Whatever you choose, the most important thing to remember is to start with a clear, high-resolution image. A great picture is a great starting point for creating great creations with our laser engravers.

What is the difference between UV and fiber laser machine?

These two machines can engrave many materials, plastic, leather, metal, etc. However, what are the main differences? Why is one so much more expensive than the other? In this blog, we will explain the difference between these two technologies and their main uses.

atomstack extension kit

From the outside, the main structure of this machine may look similar, but the technology used inside these machines is different. Fiber lasers and UV lasers use different power supplies. Another difference is that UV lasers require chiller cooling, while fiber lasers only require air cooling.

Extension Kit for S20 Pro

These machines are designed for different material engraving solutions
The main purpose of the fiber laser engraving machine is to provide engraving and solutions for the metal marking industry, the machine can mark, engrave (see the difference between engraving and marking) and engraving on all metal materials. In addition, UV lasers are designed to be a practical solution for marking plastics and glass – UV laser machines can engrave a wide range of materials, from metal to paper. Check out the list of materials this machine can engrave and mark.

atomstack air assist

As we have seen with laser UV, it can engrave more materials than fiber lasers. Ultraviolet lasers can mark on different materials, but the engraving and engraving power of metal materials is small. Fiber laser machines have obvious advantages over ultraviolet lasers in marking, engraving and engraving metal materials.

What are the advantages of UV laser machines?
The main advantage of UV laser technology is the versatility and ability to engrave on different materials including non-metallic materials. The technology can also use automated systems such as rotary engraving, linear guide engraving, conveyor belt engraving systems, and camera capture systems.

What are the disadvantages of UV laser machines?
One disadvantage of UV laser technology is that it is weak for engraving metal, and if you are looking for a machine that can engrave and engrave metal, a fiber laser engraver would be a better choice.

What are the advantages of fiber laser engraving
In short, the main advantage of a fiber laser engraving machine is its ability to engrave, mark and engrave metal materials at high speed. Fiber lasers can also mark different non-metallic materials, but the results of engraving on this material will not be as good as UV laser machines. However, this is the added advantage of fiber laser machines, being able to work perfectly on metals and on some non-metallic materials.

atomstack enclosure

What are the disadvantages of fiber laser engraving machines?
The downside of this machine comes when we want to engrave non-metallic materials. We cannot engrave or mark several materials that UV can engrave, such as wood, glass, all plastics, paper, or generally transparent objects. For example, this machine can engrave ABS and PLA, two very common plastics, in different products. When we use a fiber laser machine, the engraving on this plastic material has a 5% to 10% melting, which means that when you touch it with your finger, you may be able to feel the engraved surface just by touch. This is something that will never happen with UV laser engraving.

What are the advantages of Bach laser technology?
The strength of our machines is that we are built and designed with German galvanometer technology, ensuring that their resolution is always optimal, even when engraving at high speeds. Our machines are also designed with Panasonic sensors, allowing to still have the correct size and angle to engrave material at the correct distance.

atomstack r3

We also use BCF technology that allows our machines to engrave more material and engrave different color effects on metal or some plastic materials.

7 Tips for Buying a Laser Engraver

1. Focus on the core application: laser engraving or laser cutting
It’s easy to be drawn to how many other applications a machine can perform. A good generalist is a compromise machine in almost every way. Just because a machine can cut and engrave doesn’t mean it can do both functions well. A purpose-designed machine will always perform the core application better, so it’s no surprise that laser cutters cut better than laser engravers, and vice versa.

atomstack 130w

atomstack s20 pro

2. Throughput is almost always the key to business success.
Even if your business volume is low right now, production speed is critical. Higher throughput will provide the opportunity to reduce selling prices while increasing your profits and you can also deliver faster. These three elements are the keys to being competitive, winning and growing your laser engraving business.

3. Carefully consider the true cost of ownership, as this can have a huge impact on profit erosion.
No one is going to buy a laser engraver for a year and throw it away. For most people, it’s a long-term investment, but most buyers focus primarily on the purchase price. The actual cost of a machine should be judged by its cost of ownership over its entire working life, which is about 10 years for a good machine. Often, the cost of ownership of an inexpensive machine is much higher due to replacement parts, excessive maintenance, and lower output quality/productivity.

4. Think technology first, brand second.
We often see rows of identical laser engravers installed throughout the workshop, with buyers making purchases based on ”we always by brand X”. If a brand can provide the right machine for the job, there are certainly many advantages to brand loyalty, however, the performance of the technology should be a bigger priority

If we all insisted on only buying brands, we would all be using Nokia or Motorola phones today. Often newer and sometimes smaller companies provide innovations simply because they have to do it in order to enter the market or even survive for. Going beyond the first page of Google can save you a fortune.

atomstack x20 pro

5. Buy from a reputable, reputable supplier with application knowledge and the kits they sell.
You would expect most machinery suppliers to know what they sell, but this should never be taken for granted. Before making a purchase, push salespeople to test their knowledge of the product, its features, and especially their knowledge of the app. Don’t settle for preset demos tried/tested by manufacturers

If salespeople don’t know your application, how can they recommend the right system configuration to you? Remember that many salespeople will try to sell you what they want to sell, not what you should buy. Unfortunately, it’s not uncommon for us to see companies use the wrong tools at work because they’re misinformed.

6. Look carefully at the warranty and support guarantee
Despite the hype, especially on the Internet, the only guarantee you can rely on is that nothing lasts forever: all machines will fail at some point. The more successful you are, the harder your laser engraver is to work and the more likely it is to fail. If you’re lucky enough to be successful, it’s never a good time to take your machine down

In the event of a failure, you want to know how quickly it will be repaired and what the total cost will be, so look carefully at the fine print of your system’s warranty and more closely at your vendor’s support resources. If you can, talk to a support technician or two, as well as sales, as these types of people often have very different views on the same product.

atomstack a5 pro

7. Remember that the core foundation of good system design is a careful balance of functionality, affordability, and reliability.
By default, more powerful systems are generally less affordable and may actually be less reliable. By default, more affordable systems have fewer features and may also be less reliable. Logically, an average machine would be a happy medium for all of these things, but an average machine would most likely only provide no more than average results

Therefore, it is critical to ”buy right” and choose a system that can meet today’s needs and, to a certain extent, some of the future.

This consideration is not only related to laser power, laser marking speed, etc., but also to software functionality. For example, today you may need to mark text and logos, but tomorrow you may need to laser mark barcodes.

https://www.atom-stack.com/products/extension-kit-for-atomstack-s20-pro-a20-pro-x20-pro

Benefits of Using Laser Engravers and Cutters

Laser cutters are versatile solutions to a variety of industrial and commercial challenges. With the right laser cutting machine, industrial and commercial organizations can meet their needs for engraving, cutting or marking a wide variety of different materials with technology that outperforms the competition. Below, we’ve listed five major benefits associated with using a laser engraver or cutter. Read on to learn how the versatility and precision offered by powerful laser technology can benefit your organization.

atomstack a5 30w

Laser cutting machines are widely used
Laser cutters are versatile in that they can perform different operations depending on how the user or operator configures their settings. Laser cutting, engraving, marking and even laser etching can all be performed by the same machine under different operating conditions, and each function is suitable for a different type of application. Let’s take a look at these four functions and the differences between them:

S10 Pro laser engraving wood

Laser engraving uses a high power laser to evaporate the surface of the material, leaving visible marks between 0.02″ and 0.125″ deep. Laser engraving is a useful process for personalizing or customizing objects made of wood, leather or stainless steel, but the process may not be suitable for industrial part marking applications because the depth of cut may affect aspects of the material that are critical to it. Performance.

Laser etching is a special type of laser engraving that allows extremely shallow cuts, usually only 0.001 inches deep.

Laser cutting is the use of a laser machine to cut an entire shape or section from a selected material. High power CO2 laser machines are the best choice for cutting plastic and metal substances because they interact directly with the material, not just the pigments in the material. Some metals have high enough melting points to be laser-cut, but nearly all fabrics and paper-based materials can be easily shaped by laser cutting.

atomstack s10 pro

Laser marking is often used to create permanent barcodes or other traceability marks on metal products, such as medical devices or automotive or aerospace parts. Laser marking does not cause any physical changes to the material as it is done using only a low power laser. The beam causes oxidation under the metal surface, discoloring it and leaving a permanent, high-contrast mark. Laser marking is effective on flat, curved and round surfaces.

Vector cutting machine is accurate and reliable
Both mechanical and laser cutting are common manufacturing processes across the manufacturing industry today, but there is a reason why more and more manufacturers are choosing to rely on laser cutting machines for their needs.

Description: High power CO2 lasers like this one have rapidly replaced almost all traditional marking techniques such as dot needle, inkjet and labels. Lasers create permanent and consistent marks with low cost and high precision that no other marking technology can match.

atomstack extension kit

The laser engraving process is also superior to its industrial counterpart computer rotary engraving. Using a laser, the time and labor required to set up an engraving job is reduced, and laser engraving can be used to mark a wider range of metals and other materials.

The reason is the unmatched precision and reliability of computer numerically controlled (CNC) vector cutters, which provide absolute consistency and help minimize risk throughout the cutting process. Compared to mechanical cutting, laser cutting offers:

The ability to surface finish products, while machined parts may require post-processing to finish them
There is no direct contact between the material and the laser cutter, reducing the possibility of material contamination or accidental marking
Less heat is generated in a smaller area than mechanical cutting, reducing the risk of material warping or warping at the cut site

Some manufacturers continue to use chemical etching to mark Atomstack products, but laser marking is certainly a more efficient option. Thanks to its CNC interface, the laser marker can produce consistent marks with 99.9% accuracy on a variety of materials, even in different shapes. Processes such as chemical etching, the success of which depends on the variable absorption rate of the chosen acid material, often produce marks with up to 50% error/defect rate. Chemical etching lacks the precision and reliability of laser etching when it comes to producing high-quality, long-lasting laser marks.

A5 Laser Engraver In The Test

The software most recommended by the manufacturer is the freeware LaserGRBL. This works, but we find it relatively cluttered, cumbersome, and not very intuitive. As an alternative, we therefore use the software called Lightburn, which is also named by the manufacturer. The program costs just under 40 euros, but can be used as a free trial version for 30 days. Anyone who decides on a laser engraver should also plan for this budget. From our point of view, the investment is worthwhile.

atomstack a5 pro software

After starting the software and setting up the connected laser once, Lightburn shows the engraver’s workspace. Then the desired template, a pixel or vector graphic is imported and the size and position are adjusted. In addition to JPEG, TIFF or DXF, the software also supports numerous other formats. We now put a frame around the object and adjust the speed and laser power settings. In the first step we only expose the frame and burn it into our base to determine the exact position of the engraving. Then we position the actual workpiece and, in the second step, output the desired motif.

The laser now scans the motif and burns it into the surface underneath. The laser changes speed and power to display shades of gray. The result is burned-in areas of different strengths, which can be more or less differentiated depending on the material. While small lettering is finished after a few minutes, larger workpieces take significantly longer. How long the entire process takes can be seen in Lightburn.

The Atomstack A5 Pro is easy to use for users with experience in 3D printing and users with a basic understanding of technology. At the beginning of the test, we only had concerns about the reliability of goggles and face shields. Since our engraver is on the ground, the attached privacy screen alone does a good job. If the laser were on a table, the angle would be different and the privacy screen would be largely useless. With the glasses on, we have a good feeling and were able to watch the laser at work for minutes without feeling any negative effects. Headaches, burning eyes would be indications of possible damage, even if you are not looking directly into the laser. You really have to be careful here! The use of such machines is not without risk. You must decide for yourself whether you want to do this. It would be safest to simply observe the work process with a camera.

Even the first test drives with the A5 put a big smile on our faces. The laser does a really good job. Contours and details are burned sharply and clearly into the wood. Contrasts and shades of gray can be seen very well on the 4 mm craft wood from the hardware store. We work here at a speed of 3000 mm/min and 70 percent output and have been completely satisfied so far. However, the attempt to cut a shape out of the wood (at 1000 mm/min and 100 percent power) fails despite scanning the frame six times. The laser just isn’t strong enough here. However, experiments with the enclosed sample wood (2 mm thick) work with the settings mentioned. For example, the TechStage logo was easily cut out. However, after a total of 6 passes, only between 80 and 90 percent of the wood you made with the same material was cut through. Two repetitions would have been necessary here. With the help of a cutter knife and a little strength, the Star Wars coaster can then be easily broken out. However, the edges are then not perfect. The 5 W output power is simply not enough for cutting wood or even harder material. The situation is different with thin cardboard or felt, but tests are necessary for each material in order to determine good settings. Otherwise the laser is either too weak or the edges will burn. The actual surface also has a major impact on the final quality. On the engraving of a bamboo breakfast board, the fibers are clearly visible, which ultimately affects the sharpness of the motif.

We engrave the mirror tile used in the test from behind and use the wood engraving settings. This also works very well, but it smells like burnt plastic. The A5 not only burns the mirror surface on the back, but also makes the glass milky. The mirror is translucent in the engraved areas and can then be illuminated from behind, for example. If you don’t want that, you can cover the engraved areas on the back with paint or foil and make them opaque again.

Laser Engraver for Glass

Engraving leather or imitation leather also works well. However, smoke and odors are really unpleasant. You should work with little force here so as not to burn the material. While the attempt with a smartphone case still looks okay, the loose piece of leather warped violently during engraving. For a good result, the material would have to be stretched over a piece of wood. It is much better to engrave a leatherette headphone box. Here we had limited the performance to 35 percent.

If you don’t trust the glasses that come with it, you can also buy goggles individually to match the wavelength. In the medium term we would make another box as a privacy screen. This would reduce the risk to pets and family members and would allow for an effective exhaust system to be installed. Even if the laser only removes thin layers of the surface, these will still be burned, producing smoke and odor. When engraving wood, poor ventilation creates a thick blue haze and campfire smell. That may sound quite romantic to some, but the fun stops when it comes to processing plastic or leather. If you don’t want a foggy and smelly cabin, you have to open the window or better yet install an extraction system to avoid screeching fire alarms and health hazards.

The Atomstack A5 surprises with a simple structure and great results. At 410 × 400 mm, the A5 finally offers enough space and also works quickly and comfortably. With the A5, do-it-yourselfers get an unusual, fascinating and at the same time practical tool for the hobby room for just under 220 euros.

All in all, the laser does a pleasantly good job. It is only suitable for cutting to a limited extent, but the device is well equipped for engraving wood, plastic, cardboard, cork, leather or foam rubber. In practice, we are only disturbed by the zero point that is not marked by a limit switch, the too complex adjustment of the Z axis and the open housing.

Laser Engraver for Metal

If you want to work with wood, you should also check out our guide to saws and sanders.

Atomstack M4 Fiber 2-in-1 Laser Marking Machine

https://www.atom-stack.com/products/atomstack-m4-fiber-desktop-handheld-2-in-1-laser-marking-machine

Great S10 Pro Laser Engraver Provides Incredible Results

This laser engraver is a high-end diode laser engraver that is still very affordable compared to many of its competitors.

The Atomstack S10 Pro Laser Engraver is a fixed focus laser engraver with a 445nm wavelength blue diode laser, the laser itself has an output of 5.5 watts, perfect for anyone new to the world of maker culture Choose from general, or dedicated to laser engraving and cutting. It comes in kit form with simple instructions to help you put it together, luckily it’s not a very long process to get it done. There are no IKEA-level issues in these directions.

S10 Pro laser engraving wood

It took me about 30 minutes to get things up and running, and it was mostly straightforward. The only caveat is to place the track inside the beam to move the laser and cover the engraved area. The kit comes with all the tools you need to put it together, but it would be helpful if you had some anti-static tweezers or similar on hand to help pull the rubber tracks.

In addition to the getting started guide, the S10 Pro comes with some documentation in PDF form, which you can find by scanning the QR code on the front of the manual. This walks you through the process of using the laser, and it’s pretty easy. The user manual recommends two different software for you to use: LaserGRBL is a free and more user friendly, but somewhat basic software option, while LightBurn is paid software for more advanced users Function.

Atomstack honeycomb

Atomstack laser cutting honeycomb worktable

After downloading the software, the manual will guide you in setting the focus of the laser. After placing a protective surface under the area to be engraved, place the object to be cut or engraved under the laser, then loosen the nut on the back of the laser shield and place the aluminum focusing post under the shield. Then tighten the nut again and the laser will be at the perfect distance from the engraving for best results. Since it’s a fixed focus laser, it’s super easy to set up and get ready to burn with consistent results every time.

At this time, the accompanying manual covers the use of LaserGRBL software, but does not cover LightBurn extensively. This makes sense because if this isn’t your first laser engraver, you probably won’t need much software guidance, but if it’s your first then you’ll probably be inclined to use more streamlined software. You can also find some examples of the best settings for lasers using different materials, including cutting and engraving. These settings are also important for LightBurn and other similar software, but it’s important to remember that the stats in the book deal with millimeters per minute, so if your software uses something else, you’ll need to convert it.

Atomstack R3

Atomstack R3

That’s mostly good news in terms of how well the Atom Stack S10 Pro itself is good at engraving and cutting different materials. Despite being easy to set up and use, the S10 Pro can handle a surprising variety of different materials with excellent results. Comes with a small coaster-sized piece of thin wood for you to try, but you can carve on just about anything, from paper and card, all the way to metal and plastic, as long as you follow safety information when choosing what you pick up for Avoid fire or release of harmful chemicals.

If you use the proper settings, you can easily get incredibly good results even in the first few uses of the device. The software allows you to simply take images and use a variety of tools to convert them into usable engraving or cutting patterns. Using the speed and power settings in the manual, you just enter them into the correct fields and hit start. There are a few issues with setting exactly the right quality settings for the images and materials you’re using, but many of the results speak for themselves.

The first thing we tried was sculpting some images onto a blank coaster, after some experimentation it was easy to do many different designs without a lot of mistakes. We also tried some more intricate ideas like cutting a wooden dice tower design from a piece of wood and letting us glue it together. Not only is this easy to achieve, but it also reduces the size of the tower to fit our planks. Of course, we did end up with a very small dice tower, but that’s more limited by materials than anything else.

Atomstack Air Assist

atomstack air assist system for laser engraving machine

Experiments with other materials have also yielded excellent results. Slate, in particular, is an excellent medium for this engraver. It creates a lovely contrast between the image and the background, and it does it so quickly that it doesn’t take a whole day to get the job done, even on larger designs. Remember that you and anyone else in the room will need to wear the included safety goggles while using the device. If you plan to use it at home rather than in a private studio or elsewhere, then you’ll need to buy extra goggles for anyone planning to walk in.

Another material we tried was 3mm acrylic. In the guide it gives suggested settings to use on acrylic, but for some reason on the safety material board acrylic and other forms of plastic are simply scratched out, probably because they emit when burned Toxic fumes are emitted. Either way, the machine can cut acrylic very quickly, as long as you’re dealing with a dark enough color or one that the blue laser won’t have a problem with. Just make sure you have good ventilation.

Engraving on metal is a little more difficult, at least with your limited experience. We tried engraving on painted metal using the specs suggested in the book, and while it looked fine when painted, we were left with very faint lines after removing the paint with acetone. Even with repeated attempts at slower speeds or more passes, it was clear that not much happened.

So, are there any downsides to the S10 Pro laser engraver? If anything, it’s just that if this is more specific to beginners, it would be useful to know more about the specifics of using certain materials. This doesn’t make much of a difference to the machine, but while it mentions that it’s difficult to cut clear acrylic or plastic, it doesn’t mention the potential difficulty with lighter colors in general.

At the end of the day, the S10 Pro laser engraver is not only extremely easy to set up and use, but it’s also a powerful cutting and engraving machine for the money you put into it. The equipment will cost you over $500, and for that, you’ll get some incredible cutting power. Clever optics in the laser assembly can cut material all the way up to 15mm, depending on the material in question. Whether you’re a die-hard member of the maker community looking for a new cutter and engraver for your building, or a hobbyist looking to knock out some plaques and coasters for your friends, you’ll be hard-pressed to find this quality. Laser, for this price.