Consumer Digital Camera Features

Liquid Crystal Display
A color LCD panel is a feature that is present on virtually all modern digital cameras. It acts as a mini Graphical User Interface, allowing the user to adjust the full range of settings offered by the camera and is an invaluable aid to previewing and arranging photos without needing to connect to a Personal Computer to do so. Typically this can be used to display a number of thumbnails of the stored images simultaneously, or provide the option to view a particular image full-screen, zoom in close and, if required, delete it from memory.

Few digital cameras come with a true single-lens reflex (SLR) viewfinder, where what the user sees through the viewfinder is exactly what the camera's CCD "sees"; most have the typical compact camera separate viewfinder which sees the picture being taken from a slightly different angle and suffer the consequent problems of parallax. Most digital cameras allow the LCD to be used for composition instead of the optical viewfinder, thereby eliminating this problem. On some models this is hidden on the rear of a hinged flap that has to be folded out, rotated and then folded back into place. On the face of it this is a little cumbersome - but it has a couple of advantages over a fixed screen. First, the screen is protected when not in use and, second, it can be flexibly positioned so as to allow the photographer to take a self-portrait or to hold the camera above their head whilst still retaining control over the framing of the shot. It also helps with one of the common problems in using an LCD viewfinder - viewing difficulty in direct sunlight. The other downside, of course, is that prolonged use causes batteries to drain quickly.

Picture Storage
Most digital cameras support some form of removable memory for storing the pictures you take. Cameras will typically come with an 8 to 16 MB memory card. Depending on the resolution and compression setting, this amount of storage could hold anywhere from 10 to 200 pictures. So if you don't want to constantly be downloading pictures to a PC (which can be very inconvenient on a vacation) you'll need to purchase additional memory.

CompactFlash and SmartMedia
The two most popular forms of memory are 1)CompactFlash and 2)SmartMedia Flash RAM cards. SmartMedia cards are about the size of a matchbook and very thin. They come in two voltages, 3.3 V and 5 V, in sizes up to 128 MB. CompactFlash cards are roughly the same physical size but more durable and can store up to 512 MB.

SmartMedia cards fit into a FlashPath adapter shaped like a standard floppy disk. The whole adapter then pops into your PC or Mac floppy drive to read the card. You can also buy external adapters that will read both SmartMedia and CompactFlash cards. In addition, there are adapters that let you plug both types of cards into a PC Card slot. Some cameras support both types of cards.

Floppy Disks
One of the simplest storage systems is that of the Sony Mavica which uses standard floppy disks. It's a low-tech solution that makes the camera heavier and bulkier. But floppies are cheap and plentiful even if they only hold 1.44 MB at a time.

Memory Stick and CD-R
Sony has also created the Memory Stick which is slightly smaller than a stick of gum. Sticks can hold from 4-128 MB, larger capacity sticks are in development. This type of memory is used in various Sony digital cameras, video recorders, voice recorders and personal digital assistants. Different adapters let you transfer data from the sticks to your computer via floppy disk drive, parallel port, PC card port and USB.

Another Sony technology is a digital camera with a 77 mm CD-R (recordable) drive inside of it. The write-once CDs are two thirds the diameter of a regular CD (120 mm) and hold 156 MB to 210MB, which is enough to store over 1500 pictures at 640X480. These smaller CDs can be read by any CD-ROM drive including slot-loading drives like the iMac. CD-RW discs can also be used but may not read back on older cdrom drives. Newer drives should have no problem.

PC Cards and IBM Microdrive
There are a few other high capacity storage alternatives such as the PC Card which is about the size of a credit card. These are sometimes referred to as PCMCIA cards. Depending on the card type, they can hold from 5MB to 1 GB. Digicams, mainly professional models, can use types I, II and III PC cards

If you need still more memory, there's the IBM Microdrive. These mini hard disk drives come in sizes from 340 MB to 1 GB and fit into a CompactFlash II slot. Both PC Cards and Microdrives connect to your computer via the PC Card slot. Unless you plan on taking an insane number of pictures or need to take pictures at the highest resolutions, you won't need this much memory. But it's nice to know you can get it.

Compression and File Format
How many pictures you can take and store will depend in part on how the image files are compressed. A lot of cameras allow you to choose the compression setting (usually two or three options) or the resolution at which the image is stored. If you want the highest possible image quality, look for a camera that will let you save pictures in "CCD raw mode" which means with no compression at all.

Digital cameras don't all use the same image file formats. Many cameras have their own special or proprietary file formats which means you have to download images with the manufacturer's software. Two widespread formats are EXIF, supported by Kodak and Fuji and CIFF supported by Canon, Nikon, Pentax and several other manufacturers.

Cameras that use CompactFlash memory tend to save as CIFF while SmartMedia cameras tend to save as EXIF. Both formats use JPEG image compression, but they are not compatible because they store information differently.

The two Nickel based batteries are considerably cheaper than Lithium ones, but the Nickel batteries lose their charge much faster when not in use. The most prevalent rechargeables are NiCad. A set of NiCad batteries are good for about half an hour of intense operating time. They charge quickly and can be recharged around 700 times.

Unfortunately, NiCad batteries suffer from "memory effects." The battery holds less and less charge every time you use it if you overcharge it. To avoid memory effects, completely drain the battery before recharging or get a recharger/conditioner.

NiMH batteries don't suffer from memory effects and will last 30% longer on a charge than similar NiCad batteries. You can get an hour or so of operating time from a set of NiMH batteries, but they take much longer to recharge than NiCad batteries, up to 16 hours. Lithium batteries last twice as long on a charge as NiMH batteries, don't have memory effects and don't lose their charge as quickly when not in use. Both NiMH and LiOn batteries last for around 400 rechargings.

Another way to save battery power is to get a camera that uses an AC power adapter. A camera consumes a lot of power when it's downloading images to your computer or displaying photos on the TV so it's useful to be able to power it from a wall socket. You can also shoot with the camera plugged in, assuming you don't need a wide range of motion.

Price
Digital cameras make such great gadgets because they satisfy our love of instant gratification. No film to process; no photo developing. Connect the camera to your computer, download the pictures, and there they are on the screen. Digital cameras provide image quality equivalent to or better than what you can achieve with a traditional camera and scanner. However, a digital camera is considerably more expensive than a conventional camera or general purpose scanner.

The price for digital cameras start around $100 for kids' models and cruise on up to ten thousand plus for professional models. The average consumer who wants to play around and experiment with a new gadget can get a point-and-shoot camera with good image quality and a few options for under $300.

A serious amateur photographer will be looking for more manual control over settings like focus, shutter speed and exposure so prices will range from $650-$1800. These cameras are sometimes called prosumer cameras ("pro"fessional + con"sumer"). Someone who shoots photos for a living likely wants a digital camera that provides all the flexibility and control of a traditional camera. Like professional film cameras, professional digital cameras are expensive, starting at $2000.

Resolution
The optical resolution of a digital camera is determined by how many pixels it can capture horizontally and vertically (ie. 640x480). This depends on how many individual image sensors are present in the array. When you do the multiplication a camera with resolution of 1024x768 has 786,432 sensors and produces the same number of pixels. More pixels mean better resolution and sharper images.

Most cameras offer megapixel resolution, but it's actually one million pixels or more. Lower end models have 1.3 megapixels while high end models have 3, 4 or 5 megapixels or more. The more pixels that your camera supports, the higher the resolution and quality of photos that you can take.

To print good quality color photos at the standard film sizes 4"x6" or 5"x7" you'll need a 1-2 megapixel camera. If you plan on printing as big as 8"x10" then you're going to need to capture more information so look for 2-3 megapixels for higher resolutions. Those of you with deeper pockets and a need for high quality images can go the extra mile and buy four megapixel models or greater.

Just like scanners, digital cameras have interpolated resolution on top of optical resolution. To get interpolated resolution the camera uses mathematical algorithms to average the information from two true pixels, creating a third pixel between them. Since more pixels are mathematically generated the interpolated resolution is higher than the original optical resolution. However, true optical resolution is a more reliable indicator of image quality.

Interface
Whether you download images directly from your camera to the computer or use an external card reader, the type of interface is important. The majority of digital cameras come with interface cables that plug into a USB port; some support serial as well. Card readers and adapters can also plug into the parallel port, SCSI port or the PC Card slot which tends to be quicker than downloading directly from the camera.

There are two other download options that are becoming popular. You can use IR (Infrared) ports to beam information from your computer to your printer without the physical connection of a cable. Likewise, some cameras are capable of wireless download to your computer if it also has an IR port. This is a fairly slow type of connection, but you don't get lost in a tangle of cables.

Those users who are interested in maximum speed should keep an eye out for cameras and card readers that support FireWire (aka IEEE 1394). This type of cable is like USB but provides even faster data transfer. At the moment, FireWire is pretty pricey so it'll be a while before cameras other than professional models support it. It's more common to see digital camcorders utilizing this technology.

Video-Output
A useful feature for presentation purposes is a video-output terminal. It allows you to display your pictures on a TV or projector. Depending on the camera, you can manually advance the pictures, or the camera will automatically cycle through the saved photos. However, once pictures are erased from the camera's memory you can no longer display them on the TV, unless the camera has software that lets you upload images back into the camera. With this capability you can annotate your pictures on your computer then upload them back into the camera to make slicker slide shows. You can also record these slide shows with a VCR and add narration.

Zoom
There are two types - optical and digital. The difference between the two is somewhat analogous to the difference between optical and interpolated resolution. Optical zoom is true zoom so the camera's lens actually moves forwards and back, changing the magnification of the shot while the resolution remains the same.

Digital zoom, like interpolated resolution, is a product of the camera's software. When you use digital zoom the camera takes a picture then digitally crops it, isolating the part you zoomed in on. This part is either saved as is or interpolated to blow it up to regular size. Digital zoom results in lower image quality because digital cropping reduces the resolution. Optical zoom is better than digital zoom and some cameras offer both.

Magnification for optical zoom lenses can range from 2X to over 10X. Some zooms can be focused gradually across the full range of magnification; others have a few predefined settings. If you do go for an optical zoom, the viewfinder should be coupled to the zoom so you can see exactly what you're shooting.

Optical zoom works in much the same way as a zoom lens on a traditional camera. Produced by the lens system, it is the magnification difference between minimum and maximum focal lengths. Importantly, in digital cameras this magnification occurs before an image is recorded in pixels.

By the early 2000s many digital cameras came equipped with motorized optical zoom lenses which provided an effective range from wide-angle to telephoto. These generally come in a range between 3x and 10x, but it can be higher. The "times" notation can be confusing, with "3x", for example, having a different precise meaning for different cameras. This is because the actual focal length of a digital camera relates to the size of its sensor. Digital camera specifications therefore generally also cite a "35mm equivalent" lens rating. A 3x zoom lens is the standard offering and generally implies an "equivalent" focal length of some range between 35mm and 140mm. Some cameras have a gradual zoom action across the total focal range, others provide two or three predefined settings.

Digital zoom is nothing more than the cropping of the middle of an image by a digital camera's software. When an image that has been digitally zoomed 2x is reproduced, either on a display monitor or by being printed, it will effectively be viewed at half its original resolution. A more sophisticated from of digital zoom uses the digital camera's software to interpolate the cropped image back to its original resolution. In this event, fewer of the original pixels are used to represent the enlarged image, which will appear less sharp as a result. Some digital cameras provide a digital zoom feature as an alternative to an true optical zoom, others provide it as an additional feature.

For close-up work, a macro function is often provided, allowing photos to be taken at a distance as close as 3cm but more typically supporting a focal range of around 10-50cm. Some digital cameras even have swiveling lens units, capable of rotating through 270 degrees and allowing a view of the LCD viewfinder panel regardless of the angle of the lens itself.

Macro Mode
To take extreme close-ups like photographing a stamp or coin collection, you'll want a camera with a macro mode. A macro lens can act as a normal lens but also lets you focus on an object as close as 3 cm. Macro mode works best from 10-50 cm.

Built-in Flash
Built-in flashes are a common feature of digital cameras and have a range of 10-16 feet. For the average user, autoflash is just fine. But there are other flash modes that can be advantageous in different situations. Two useful flash modes are red-eye and fill.

Red-eye mode helps reduce those glowing red eyes that make family photos look like a night of the living dead convention. Two flashes are emitted; the first constricts the iris so that less light bounces back from the eye when the second flash goes off. Fill mode only uses enough flash to fill in the shadows when shooting on sunny days. Having a manual override is useful for shooting in places like museums or concerts where flashes aren't allowed.

Ergonomics
Unlike traditional film cameras, digital cameras can vary widely in their appearance. Some look like traditional cameras, others are designed more like camcorders. They can range in size from ones that you can slip into your pocket to ones that have to be slung around your neck or require a two-handed grip.

In general, the more features a camera offers the bigger and bulkier it is. This is why compact cameras weigh around 300 g and professional models can weigh over 1 kg. Also consider how easy it is to finger the camera's control buttons. In the end, the design that's right for you will have quite a bit to do with how the camera feels in your hands.

Compatibility
Most cameras are compatible with both Windows and Macs. But the software bundled with the camera might support one platform better than the other. Also check to see what type of connections your computer supports. If a camera stores pictures on a PC Card, for example, you may have to buy an adapter for your computer.

Software
The basic software that comes with a digicam lets you download images from the camera to your computer. This is usually proprietary software so you can't download to just anyone's computer. Depending on the program, you can view thumbnail pictures first and then decide which pictures you want to download in their entirety. Also find out if you can download your pictures en masse or if they have to be transferred one at a time.

Better software bundles also include image-editing software. The programs you get are often limited or "lite" versions of graphics programs like Adobe PhotoDeluxe. If you want to do a lot of image manipulation, you might have to upgrade to a full-featured program, but limited versions should be adequate for most retouching.

It's also good if your camera comes with image cataloguing software since the average camera assigns file names to your pictures that are not in any way descriptive. These programs are often very simple but will help you keep track of your photos.

Time Lag
Digital photography requires a little more patience than traditional film photography. When you press the shutter button the camera doesn't take the picture right away. It takes 1-2 seconds to charge the CCD array and optimize settings like focus, exposure and color balance, then the picture is taken.

There is a second lag of 2-30 seconds between shots when the camera is busy processing, compressing and storing the image. As newer cameras come out, the time delay is shrinking. Most cameras will also automatically power down after 30 seconds to 5 minutes to conserve the batteries. You then have to wait maybe another 15 seconds for the camera to power up again to shoot.

Burst Mode
These inherent time lags can make fast action shots difficult. You can get cameras with a special burst mode which allows the camera to take several pictures in a row by holding the shutter button down. Photos can be captured at 1-3 shots per second with as many as 15 images in one burst. In burst mode, a camera either records images at lower resolution or temporarily stores the images in its memory, waiting to do all the processing, compressing and storing at the end of the burst. This latter method does not reduce resolution.

Sensitivity
When you buy film it comes in different speeds defined by ISO numbers (ie. 100, 400). Digital cameras also come with different ISOs. The higher the speed, the more sensitive the film is to light so 100 speed film is good for outdoor shots, but 400 film is better for indoor shots. Faster film is also needed to capture quick motion shots. Exactly the same considerations go into choosing the ISO of a digital camera. Think about the light conditions and type of subjects you plan to shoot and pick an ISO accordingly. Speeds range from 100-3200, and some cameras have multiple ISO settings, typically 100, 200 and 400.

Manual Controls
If you were the head of the photography club in high school and want the digicam to prove it, you might want to spend the extra cash to get a model with more manual control. Most cameras automatically set focus, aperture and shutter speed, but those settings won't always give you the effect you want. Manual focus allows you to choose what will be in the sharpest focus.

Opening or closing the aperture regulates the amount of light that enters the camera. You can compensate for low light by using a larger aperture setting or f-stop. The higher the f-stop, the smaller the aperture, the less light enters. The broader the f-stop range of a camera the more control you have. A typical f-stop range is from f2.8 to f16.

Shutter speed determines how long the image sensors/film is exposed to light. To freeze rapid action you can increase the shutter speed. Decreasing the shutter speed can offset low light conditions or produce motion blurring effects. Speeds can range from one second to 1/10 000 of a second, but an average range is 1/2 to 1/500 of a second.

Exposure Compensation
You can compromise between automatic and manual settings with a feature called exposure compensation which allows you to darken or lighten a picture while still in automatic mode. Exposure compensation settings usually range from +2 to -2 in full, half or third of a stop increments. Automatic cameras can have difficulty dealing with scenes that are very bright, very dark or have high contrast.

Every digital camera has a fully automatic mode metering that allows a user to simply point and shoot. However, in common with traditional film cameras, they also offer a number of different ways of controlling the exposure of an image. A good exposure will result in an image that has balanced contrast and brightness, with no areas that are too bright and washed out or too dark which also creates loss of detail. Center weighted metering is the system used by many digital cameras to measure the correct exposure. With this system, the camera measures the amount of light mostly around the center area of the lens and less towards the edges. For many situations this works well, but in some lighting situations, center weighted metering can produce poorly exposed photos. If the scene to be photographed has light areas and dark areas, for example in the shade of trees on bright sunny days with lots of sunlight and shadowed areas, center weighed metering will often either overexpose the bright sections, or underexpose the dark sections. Some digital cameras offer matrix type metering systems, which break the scene into several areas and measures each individual area's exposure. This results in an image with a balanced exposure throughout. Spot metering is another option included on some digital camera models. This measures the exposure at a small, precise portion in the center of the lens, allowing the user to ensure perfect exposure on a particular section of the scene.

Programmed auto-exposure modes keep the basic exposure settings automatic while providing manual access to other camera settings. Some offer aperture- and shutter-priority modes which allow the user to set the f-stop or shutter speed, and then automatically calculate the other settings needed to expose an image correctly.

Some cameras provide a manual exposure mode, allowing the photographer a significant degree of artistic license. Typically, four parameters can be set in this mode: white balance, exposure compensation, flash power and flash sync. Different types of light (outdoor, fluorescent, and so on) will have an impact on the colors in images. White balance provides a means to correct for the effect of the lighting conditions, such as sunny, cloudy, incandescent or fluorescent. Exposure compensation alters the overall exposure of the shot relative to the metered "ideal" exposure. This feature is similar to that a SLR cameras, allowing a shot to be intentionally under- or over-exposed to achieve a particular effect. A flash power setting allows the strength of the flash to be incrementally altered and a flash sync setting allows use of the flash to be forced, regardless of the camera's other settings.

Some cameras offer what is referred to as "automatic exposure bracketing". With this, several frames are shot when the shutter is released, each at a different exposure setting. The exposure that gave the best result can then be selected.

Most digital cameras offer a number of image exposure timing options. One of the most popular is a burst mode that allows a number of exposures to be taken with a single press of the shutter. The speed and number of sequential shots that can be captured in a burst is dependent on the amount of internal memory the camera possesses, the image size selected and the degree of compression applied to the photos. Cameras with fast burst rates - specified as a fps rate - generally have a large amount of "buffer memory", which is used as a temporarily store prior an image being processed and written to the camera's primary image storage medium. By the early 2000s, the capability to shoot up to 15 shots in a burst at rates between 2 and 6 fps was fairly typical. Also common is time-lapse, which delays multi-picture capture over preselected interval. Other examples are the ability for four consecutive shots to each use only a quarter of the available CCD array, resulting in a single frame with four separate images stored on it and to take multiple exposures at a preset delay interval, tiling the resulting images in a single frame.

Self-Timer
If want to be included in group shots or want to take pictures of yourself when you're the only one around, a self-timer is really handy. Self-timers have a preset delay before the shutter snaps, giving you about 10 seconds to run into the shot. Another gadget is a wireless remote. You can take your time getting into position then aim the tiny remote control at the camera to trigger the shutter. A self-timer is a common feature, typically providing a 10-second delay between the time the shutter is activated and when the picture is taken. 

Flash
All modern day digital cameras have a built-in automatic flash, with a manual override option. The best have a working range of up to 12ft and provide a number of different modes, such as auto lowlight and backlight flash, fill flash for bright lighting shadow reduction, force-off for indoor and mood photography and red-eye reduction. Red-eye is caused by light reflected back from the retina, which is covered in blood vessels. One system works by shining an amber light at the subject for a second before the main burst of light, causing the pupil to shrink so that the amount of red light reflected back is reduced.

External Flash
If you need more power than a built-in flash can supply, the camera has to have an external connector for a separate flash. A portable battery-powered flash can be mounted on the body of a camera via a "hot-shoe," a small U-shaped fitting on a camera. Other cameras have special sockets where you can connect an external flash via a small cable or sync cord. This way the flash is separate from the camera but still draws power from the camera. With both methods the flash is synchronized with depressing the shutter button.

Annotation
To help you remember when and where you shot a bunch of pictures, some digicams offer annotation features. The most common is a watermark with the date and time or other text which appears on the picture or is hidden in the image file. On some cameras, the LCD screen is touch sensitive, allowing you to write notes on your images with a stylus. Another way to annotate your pictures is through sound. A camera with a built-in microphone can tape your comments and create sound files you can play back and edit after you download the camera to your computer.

Another feature commonly available with film cameras that is now available on their digital counterparts is the ability to watermark a picture with a date and time, or indeed some other chosen text. And that's not all. The recent innovation of built-in microphones provides for sound annotation, in standard WAV format. After recording, this sound can be sent to an external device for playback, or played back on headphones using an ear socket. Some cameras even offer an audio made that effectively allows it to be used as a voice recorder.

Lenses and Effects
With film cameras there are a lot of accessories like wide-angle or telephoto adapters, interchangeable lenses and filters. Some digital cameras can use these same accessories, but they're the prosumer or professional models. Another interesting feature you can get with more expensive cameras is a swiveling lens. The camera has a swivel point in the middle so that the half with the lens can rotate in relation to the half with the LCD screen. This function will let you see yourself on the LCD before you take a picture of yourself. You can also swivel the LCD so that it doesn't wash-out when you're shooting outdoors. Digital cameras are often described as having lenses with equivalent focal lengths to popular 35mm-camera lenses. In fact, most fixed-length lenses on digital cameras are auto-focus and have focal lengths around 8mm; these provide equivalent coverage to a standard film camera - somewhere between wide-angle and normal focal length - because the imaging CCDs are so much smaller than a frame of 35mm film. Aperture and shutter speed control are also fully automated with some cameras also allowing manual adjustment. Although optical resolution is not an aspect that features greatly in the way digital cameras are marketed, it can have a very important role in image quality. Digital camera lenses typically have an effective range of up to 20ft, an ISO equivalency of between 100 and 160 and support shutter speeds in the 1/4 of a second to 1/500th of a second range.

Image Effects
Certain cameras can produce different artistic image effects. For example, pictures can be taken in monochrome, sepia or negative modes. Panoramic views are possible, as are deliberate multiple exposures where you superimpose two or more images. Some cameras can divide the CCD array into four and use each quarter to store a different picture. The result is a photo with four separate images.

Apart from their use for artistic effect, the monochrome mode is useful for capturing images of documents for subsequent optical character recognition (OCR). Some digital cameras also provide a "sports" mode - which adds sharpness to the captured images of moving objects - and a "night shooting" mode which allows for long exposures.

Panoramic modes differ in their degree of complexity. At the simpler end of the spectrum is the option for a letterbox aspect image that simply trims off the top and the bottom edges of a standard image - taking up less storage space in the process. More esoteric is the ability to produce pseudo-panoramic shots by capturing a series of images and then combining them into a single panoramic landscape using special-purpose software.

Time Lapse and Video
Digital cameras are also capable of time lapse photography. The camera takes a series of pictures with a certain interval of time between shots. This technique is often used in nature photography to capture slow events like flowers growing. It's useful to have a camera with a tripod mount if you plan on doing time lapse. To capture faster real-time events, some digicams can record a few seconds of low resolution video footage.

More features
A couple of other features which demonstrate the digital camera's close coupling with other aspects of PC technology are a function that allows thumbnail images to be emailed directly by camera-resident software and the ability to capture short video clips that can be stored in MPEG-1 format. Some cameras record silent video only and limit the length of the clips; others sound with the video and allow the clip to be as long as the camera is capable of saving to its storage media.

Borrowing from technology developed for their video camcorder brethren, some digital cameras feature image stabilization systems. This is particularly useful when used in conjunction with high powered zoom lenses, when it can be very difficult to keep the camera still enough to create a clear image, especially in low light situations and when using a slow shutter speed. Image stabilization is employed to help overcome the effects small movements of the camera.

Higher-end models also provide support for two memory cards and features more commonly associated with SLR-format cameras - such as detachable lenses and the ability to drive a flash unit from either the integrated hot-shoe or an external mount. Indeed, by early 2000 a number of major manufacturers - including Nikon and Kodak - were preparing to follow rival Minolta's lead in pushing digital cameras into the mainstream professional market by offering single lens reflex technology at "affordable prices". While the differential between professional and consumer models remains significant, it decreased dramatically during the late 1990s - as has the gap between digital cameras in general and their analog counterparts.

Digital camera features checklist

Contact: email [email protected]