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1080P digital camcorder High quality action cameras. Take beautiful HD videos and fantastic photos with a small lightweight camcorder that fits easily in your pocket. Ideal for outdoor sports and travel photography.
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Action Camera Telephoto Lens - Zoom In and Fisheye Removal non gopro change replacement drone quadcopter 4k rc 4.35mm 5.4mm

Action cameras are great but the super wide angle 170 degree lens is not suitable for all applications. It produces lots of curvature around the edges of the scene. This is fine for action sports, where you want to include as much peripheral vision as possible. For other pursuits such as drone photography or for a general purpose camera we prefer a narrower telephoto lens. It is difficult to find action cameras that have a telephoto lens, as most come with a fisheye lens as standard.

There are two approaches to getting one. You can modify your existing action camera to install the telephoto lens, or you can buy a camera with a narrower telephoto lens pre-installed. We tried to change the lens on an SJCam SJ4000 and found that the process is difficult. We therefore set about sourcing an action camera with telephoto lens pre-installed. The result is our Vision camera that is designed to be a general purpose camcorder for both action and non-action uses.

Modify your GoPro or SJ4000

It is possible to modify a GoPro or SJCam to change the lens for a narrower one. However the process can be difficult and there is a risk of damaging the sports cam. You have to unscrew and remove the original lens. It is fastened with an M12 thread and threadlock has been applied at the factory. It takes a lot of force to break the threadlock. You have to grip the original glass with pliers to unscrew it, and there is a danger of damaging the mount by applying too much force. Also when installing the telephoto optics it has to be screwed in to the correct distance to set the focus. This can be challenging, and sometimes you meet resistance from the old threadlock that stops it screwing in correctly. We know this because we fitted a 4.35mm telephoto lens to an SJCam SJ4000 ourselves to give a linear image. You can see footage from our modified camera.

Buy a Model with it Preinstalled

A more simple and reliable solution is to purchase an sports camcorder that comes with narrower optics installed. That is what we set out to achieve with our Vision model. We chose 120 degree diagonal FOV (3.3mm) to be halfway between the very wide 170 degree, and the almost linear 4.35mm. The 4.35mm glass is good for general purpose photography and drones, but less suitable for sports as the vibrations are magnified. By going halfway between the two the ~100 degrees horizontal view is suitable for both sports and general purpose photography. There is still some curvature at the edges of the image, but it is less noticeable than with the standard fisheye viewpoint.

The big advantage of the Vision is that it comes with great non fisheye optics preinstalled.

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