bucko 1 Posted March 9, 2022 Share Posted March 9, 2022 hi, we only had a reversing camera on our autoroller 694,we paid a fair bit of money out to have it changed to a rear view/reversing camera so we can see behind whilst driving along, the view we have is what they call fisheye but it does not give a true reading of how close the cars behind actually are i:e at a junction a car may be directly behind us but on camera it looks about 3 cars length back, we have been told they are all fisheye cameras but what i want to ask is can we get a direct standard view camera fitted or is the guy correct in saying we need to get used to the fisheye effect which is driving us crazy lol,thanks in advance !! Link to comment Share on other sites More sharing options...
Tracker Posted March 9, 2022 Share Posted March 9, 2022 I found that a flexible Fresnel lens on the back window worked tolerably well for close up rear views, but they do discolour with age, and depend on your van having a rear window! The combination of standard reversing camera, Fresnel lens, and outside rear view mirrors was good enough for me for seeing behind whilst driving and for most circumstances but sometimes in a very tight spot my co-pilot might need to 'see me back' by standing outside where I could see her in the mirror whilst waving her arms in an inexplicacle way! The addition of a sturdy steel rear bumper took much of the risk of body damage away. I never have found reversing sensors that bleep at you totally reliable. Can you not simply reinstall your old reversing camera? Link to comment Share on other sites More sharing options...
BruceM Posted March 9, 2022 Share Posted March 9, 2022 If you have just a single rear camera I suspect that the advice you’ve been given is correct. My van has two cameras, one with a short focal length (wide angle) that points down for reversing, and one with a longer focal length that points backwards down the road (not that I use the latter much as I prefer to drive with my side mirrors). To have a single camera that produced an image encompassing both the rear of the van for reversing plus the view further down the road its lens would have to have a super short focal length – ie something akin to fisheye. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted March 10, 2022 Share Posted March 10, 2022 This advert is for a twin-lens reversing camera https://www.parkingcameras.com/store/cam222wnv-4-pin-connector-twin-lens-white-bracket-camera-2-x-1-3-sony-ccd-image-sensors-s-steel-bracket.html One of the lenses is narrow-angle (45 degrees) to provide a continuous view behind the motorhome while it is being driven, while the other lens is wide-angle (120 degrees) to provide a view down the rear of the motorhome when it is being reversed. (The 'aim' of each lens should be apparent from the image attached below.) The view from the wide-angle lens needs to cover the full width of the motorhome's rear. If that lens is in use when the motorhome is being driven forwards, it's to be expected that a view of traffic close behind the motorhome may be distorted/unpredictable. (I vaguely remember a 'smart' single lens camera being developed that changed from narrow to wide angle (and presumably also from look-back to look-down) according to whether a motorhome was going forwards or backwards. Not sure, though, whether it came to market.) Link to comment Share on other sites More sharing options...
Brian Kirby Posted March 10, 2022 Share Posted March 10, 2022 bucko 1 - 2022-03-09 4:48 PM hi, we only had a reversing camera on our autoroller 694,we paid a fair bit of money out to have it changed to a rear view/reversing camera so we can see behind whilst driving along, the view we have is what they call fisheye but it does not give a true reading of how close the cars behind actually are i:e at a junction a car may be directly behind us but on camera it looks about 3 cars length back, we have been told they are all fisheye cameras but what i want to ask is can we get a direct standard view camera fitted or is the guy correct in saying we need to get used to the fisheye effect which is driving us crazy lol,thanks in advance !! There may be a misunderstanding, or whoever supplied the camera took a very narrow understanding of what you were asking for. If, as you say, you asked for "a rear view/reversing camera" that might have been interpreted narrowly as meaning that you wanted just a single camera, in which case I guess what was fitted (kind of :-)) meets that narrow brief. The point being that, as can be seen from Derek's post above, the alternative, and IMO far more practical alternative is a so-called twin lens (but actually twin camera - each with its own separate CCD) system, with two separate cameras contained in a single casing, each equipped with a lens appropriate to its intended function. This involves an additional complication for installation, and each camera then has to be separately connected back to the monitor, either via an intermediate "switch box" that is actuated when reverse gear is selected to switch between camera feeds, or to a monitor equipped with a reversing signal input that itself selects between the cameras automatically. In a 2019 Ducato/Boxer, the reversing signal will be electronically derived via tapping into the base vehicle's CANBUS, rather than from a physical connection to a reversing light or a gearbox mounted switch. It is possible, though I think unlikely, that the cable between the camera and the switchbox/monitor has sufficient wires to carry the two separate camera signals, or that the monitor (or switchbox) is suitable for a twin camera set-up. So, it may be that what you got was the cheapest (easiest? :-)) system to install to replace a single reversing camera (which was presumably only activated when reverse gear was selected). Exchanging that for a twin lens (twin camera) set up, such as you seem to have anticipated, would be likely to involve stripping out the whole of the original installation and starting afresh with new camera(s), new cables, possibly new reverse signal link, and new monitor - meaning more time, possibly more components and, inevitably, greater cost. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted March 10, 2022 Share Posted March 10, 2022 I've now noticed that there is an earlier thread (January 2021) that provides more background and much more detail of Bucky 1's present system that comprises two separate cameras (see penultimate posting on the 2021 thread). https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/reversing-camera/57305/#M685319 As I understand Bucky 1's complaint here, it's that the retro-fitted 'looking backwards' camera, that's in operation when the motorhome is being driven, provides an image that suggests that a vehicle that's quite close to the motorhome's rear may be further away and that this is due to the camera having a 'fisheye' lens. It's quite possible that the retro-fitted camera's lens is still fairly wide-angle and is producing this irritating 'distance distortion' phenomenon as a result. Me, I'd try angling the camera downwards a little more: this should not harm long-distance looking-backwards viewing too much and it might make the view of a vehicle's position behind the motorhome seem more accurate. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.