Save your time with a simple setup process that can get you up and running on the Amcrest View mobile app in no time at all. You don't have to be tech savvy to get setup quickly and painlessly. Simply power it on, download the app, scan the QR code, and within just a few taps you’re ready to go. Day to day operations are a breeze thanks to the simple interface which allows you to take advantage of the camera's powerful features.

HikvisionCamera

Above we mention that focal length is related to focus distance.  Focal length is the principal distance of a camera when it is focused at infinity. In photogrammetry we are interested in the camera’s internal geometry at the time photos were taken – so it is the principal distance that we want to know precisely in photogrammetry.

High definition recordings and snapshots are only as good as how quickly and easily they can be accessed. Amcrest Cloud was created to ensure that you don't miss anything, no matter where you are. Regardless of how far you are from home, you can login from a computer (PC or Mac) or through the Amcrest Cloud smartphone app to instantly pinpoint your footage through an intelligent timeline on an intuitive interface and play it back in seamless and brilliant 8MP quality. The Amcrest Cloud app also can be configured to send you on-the-go alerts. Live viewing is included free. Additional 7-day, 15-day, and 30-day storage plans are available starting at $6 per month.

Learn how to use PhotoModeler with your camera to create detailed digital models: www.photomodeler.com/products/why.html

Any user of Amcrest products can take full advantage of the expansive support content available. Between our YouTube channel, knowledge base, forums, and US email/phone support team, anything and everything can and will be answered quickly and simply. In addition, each purchase with Amcrest will include a 30-day money back guarantee as well as a 1-year replacement warranty.

When you buy a digital camera you will often see the specification “equivalent 35mm focal length”. What does this mean? Most digital cameras have imaging chips that cover much less area than a standard 35mm film frame. Since 35mm film cameras were the standard for so long in photography, much of the techniques and methods were developed around them. A 35mm film camera has a negative that is about 36mm wide by 24mm high (the “35” comes from the physical width of the film stock that is exactly 35mm wide).  A ‘normal lens’ (has a field of view that appears ‘natural’ to humans) on a 35mm film camera has a focal length of 50mm.

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Note: A technical photogrammetry term that you may come across is the “Principal Distance”.  Strictly, the Principal Distance is the distance mentioned above (i.e. distance from imaging plane to the lens optical sensor), and the focal length is the principal distance when the lens is focused at infinity. See below for more information on focus vs focal length. When PhotoModeler lists focal length for a camera, it is actually the Principal Distance that is shown.

Cameras can have fixed lenses (sometimes called ‘prime’ lenses) which have just one focal length, or zoom lenses which allow the focal length to be varied (for example between 18mm-55mm, or 55mm-200mm). For high accuracy photogrammetric work in PhotoModeler, a fixed (or prime) wide lens (such as a 20mm lens on an APS-C frame camera) is recommended as the primary option, but different applications may require different focal lengths, and cameras with adjustable zoom lenses can still be used to achieve very good results with some extra procedural care over the focal length.

Featuring the latest Sony Starvis CMOS progressive scanning image sensor and Chipset, the Amcrest ProHD camera soaks in the entire scene, dynamically painting all the vivid colors and rich imagery, pixel by pixel, onto your computer screen or smartphone in full 3840x2160 resolution. No need to strain your eyes, lean in close, or play the guessing game when you have this level of detail.

PTZCamera

A strict technical definition of focal length is difficult without providing a lot of background in lens theory, so we will use a simplification. You can think of focal length as the distance between the imaging plane (e.g. the image chip in a digital camera) and a point where all light rays intersect inside the lens (the ‘optical center’). So a focal length of 20mm means that the distance from the optical center to the imaging plane is 20mm long (about ¾ of an inch). What does the focal length number mean?

There is some ability to calibrate a camera (which solves the principal distance) at one focus and execute your photogrammetric project at another focus.  The actual discrepancy that is acceptable depends on your accuracy requirements and how much the focus changes.  Generally a calibration done at 2m/6ft focus distance is acceptable for projects up to infinite focus (again depending on accuracy requirements), but may not be acceptable for a project where the focus distance was 50cm/20in.

Let’s say you take a picture of an automobile with two cameras, a 35mm film camera and a smartphone camera. You stand in the same spot and take two photos, one with each camera. In both cases you want to take a photo of the automobile that fills the frame. If the 35mm film camera lens has a 50mm focal length, the digital camera’s focal length might be 4mm. So even though they are very different numbers they produce the same result because of the size of the imaging surface. So the “equivalent 35mm focal length” for this smartphone camera at 4mm is 50mm.

PhotoModeler is one of the leading tools for photogrammetry (the science of generating measurements and accurate 3d data from photography).

Focal length is a number that is vital to photography and photogrammetry but often misunderstood. What is focal length?

In many cases though, the advantages of using focus (i.e. crisp targets and distinct features) with subtle effects on principal distance/focal length, outweigh the advantages of keeping focus and principal distance constant (i.e. potentially causing blur in some photos taken at a different distance).

50xOpticalzoom SecurityCamera

Modern digital cameras can have imaging chips that are as small as 6mm by 4mm; some Smartphone cameras are even smaller, and then up to full 24mm by 35mm size.  A very common size is the APS-C format at 16mm by 24mm. This smaller size affects what is considered to be a ‘normal’ focal length.

Create distinct motion detection zones to completely customize control over what you’re monitoring. This is an effective way to ensure that you only record what you need when its important. Each zone includes its own sensitivity and threshold meters so you can fine-tune it exactly to your liking. Let the Amcrest camera hold its focus so you don’t have to lose yours.

Camera manufacturers sometimes list these equivalents because some photographers are more familiar with 35mm cameras and they want to make it easier to understand. It also gives us a standard of reference for all the different format sizes. They may also list the multiplier factor. For example, the APS-C multiplier is around 1.6x.  So a 32mm lens on an APS-C camera (like the Nikon D3200) would act like a 50mm lens on a 35mm film camera. Does focusing affect the focal length?

In addition to Amcrest Cloud, the Amcrest ProHD camera can also record to an FTP server, onto your local computer, a MicroSD Card (Up to 128GB, Not Included) or to any Amcrest NVR (Not Included). You'll have full control over your recordings and can manage them however you'd like.

Optical camerameaning

All lenses have a stated or specified focal length value (or range of values for a zoom lens). This printed number is actually its nominal length or the principal distance when the lens is focused at infinity. As you focus on objects that are closer to the camera, the principal distance changes.  So for example, a 50mm lens focused on an object a few feet away might have a principal distance of 55mm lens at that time. The most extreme example of this is with a macro setting (a lens setting that allows you to focus on very close, very small objects, under 5″ in size for example). A lens that has a 50mm nominal focal length (so a 50mm principal distance when focused at infinity) might in fact have a 100mm principal distance when focused at a few inches! This is why it is good with photogrammetry (where precise geometry is needed) to calibrate a camera at the distance you will be working with.

Your stored recordings and pictures are precious, and having that data at hand is the whole point of using a security camera. Whether sharing with friends and family, or presenting evidence in a court case, it is important to be able to immediately identify, track down, playback, and export what you want, when you want it. The Amcrest camera’s intuitive searchable timeline will make your life easier, save you time, and act as a sophisticated built-in video player.

Input your surveillance technology specifications to estimate the necessary storage space needed to support your unique environment.

The Amcrest View Pro app frees you from having to check in just to find out what’s been happening lately. Instead, get immediate push notifications and alarm details sent to your smartphone while you’re on the go. Launch straight into the app, choose an event from the Event List, and jump right to the relevant recording or snapshot. Life doesn’t wait around, and neither should you.

Cutting-edge night vision technology allows you to get a crystal clear picture even when it's dark. This camera has 2 IR LEDs that transmit their infrared rays in a frequency imperceptible to the human eye. The IR lights cast brightly which provides an astounding 164 feet of night vision range. With this powerful feature, you can gain total awareness over the previously unseen and do so in a way that is undetectable.

A carefully crafted 2.7mm~12mm lens with a max aperture of F1.4 generates striking visuals owing to the 110° viewing angle. With such a wide field of view you will have no problem keeping what you care about in your sights.

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* When referring to drive capacity, one gigabyte, or GB, equals one billion bytes and one terabyte, or TB, equals one thousand billion bytes. Your computer’s operating system may use a different standard of measurement and report a lower capacity. In addition, some of the listed capacity is used for formatting and other functions and will not be available for data storage. Quantitative usage examples for various applications are for illustrative purposes. Actual quantities will vary based on various factors, including file size, file format, features, and application software. Actual data rates may vary depending on operating environment and other factors. Amcrest reserves the right to change, without notice, product offerings or specifications.

The Amcrest ProHD camera features secure SSL connections via HTTPS to comply with modern WiFi standards for encrypted connections. This way you can always be assured that, as you play your footage, you’re also playing it safe.

A camera typically has focal length in a range of 10mm to 500mm.  Different types of camera can have different ranges and speciality lenses can extend outside this range as well.  A 10mm focal length would be a very wide lens (capturing a lot of the scene), and 500mm would be a very narrow lens (capturing only a small part of the scene – giving a large magnification like binoculars or a telescope).

The focal length number tells us how much of the scene is captured in the picture. The lower the number the wider the view, and the more we can see.  The higher the number, the narrower the view, and the less we can see.   This is illustrated below – where the camera is stationary and the focal length (in white numerals) changes: