cheap alternative to rear view camera

I suppose many of you share the frustration of trying to back a Prius into a tight parking spot. I introduced the fake cell antenna mounted on the front license plate holder to assist me in locating the front bumper, but, until now, I've been bothered by the invisible back bumper. As it takes very little to scratch the paint, I've been limiting my parallel parking to fairly long spaces.

I went to a local RV supplier, which some of you may view as cavorting with the enemy, and got one of those vinyl wide angle lenses you stick on the back of your RV, van, station wagon or PRIUS, so you won't drive over your kid's bicycle with the kid still on it.

I had to trim it a bit, but it fit snugly once I made a paper pattern and measured. Nice that there is a slight space between the glass and the plastic framing, so that the edge of the lens slipped in behind the framing and made a nice appearance.

I used an orange traffic cone we have at work to measure the difference in visual field. I was astonished at the difference. At distances less than 3 feet, I couldn't see the cone. At 3 feet, the top of the cone appeared in the lens. I was hoping for a shorter range, but 3 feet seemed an improvement.

I kept moving the cone further back to see how far it would have to be before I could see it in my rearview mirror without the lens. At 20 feet, and still no cone, I decided that being able to see something 18 inches high only 3 feet behind me was a real plus.

I mounted the lens on the driver's side of the rear window, on the lower glass piece, of course. The angle on the upper window is too severe and you can't see anything through the lens fromthe driver's seat. I thought it would be too distracting, especially when changing lanes to the right, to have the wide angle on the pax side of the car. As it is, the lens covers almost half of the lower pane, but I don't think it will affect my vision in normal driving.

I saw an Insight at an energy fair over the weekend that belonged to a pilot. He tricked his car out and removed both side mirrors and replaced them with a camera and video. While it looked hot, and the screen on the dash was cool, I thought it unwise to remove the side mirrors because if the monitor or camera failed, he would be pretty blind in that very light weight car. His system cost him about 500 bucks, considerably more than the 12 bucks I spent for my failsafe lens.

Bob

 

<div class='quotetop'>QUOTE(Rick Grahn\";p=\"96234)</div>

Yes, it does, although it's too hard to look in so many places when you are changing lanes. Maybe as I get more used to it, I will incorporate it into my lane changing scan. The view out the back is quite wide angle so the apparent distances get distorted; ok for parking, but risky for judging fast moving cars.
Bob

 

Re: Okay, I think I get it.

<div class='quotetop'>QUOTE(Godiva\";p=\"96474)</div>

Not sure a picture would work for this, as it's pretty subtle, although when I get home, I'll take out the digital camera and give it a try. Meanwhile, here is a better description of the lens and how I mounted it:

The lens is made of flexible vinyl, is rectangular with rounded corners and comes in several sizes. Mine is 8x10 inches. One side is smooth and the other side has a gazillion tiny concentric grooves somewhat like the surface of a phongraph record. These grooves form a Fresnel lens like that used in lighthouses. The effect is to vastly increase the field of view.

The lens has a top and bottom and is so marked. You can cut the lens to fit, but you should work as much from the center as possible rather than trimming from only the top or bottom. This keeps the orientation of the lens pretty much where it's supposed to be.

I used a sheet of paper to make a pattern before I cut the lens. The plastic framing around the rear window has a slight gap between it and the glass which is enough to insert the edge of the lens, and you should make sure you include that in your pattern so that the lens will fit better and look slicker.

The best position for the lens is on the driver's side. I positioned mine just to the left (looking forward from the rear) side of the little logo roundel in the middle of the lower edge of the window. This put the center of the lens right between the left and center rear seat headrests as I look through my rear view mirror.

I only had to trim about 1/4in off the top edge and 1/2in off the bottom edge to get a good fit. Your pattern will not be a right angle rectangle because the top edge will need a slight curve upwards if the lens is to fit squarely.

Clean the lens with mild soap and make sure you get all the soap off. Get a squirt bottle of water and wet the smooth side. Apply it to the rear window and squeegee out the water. It takes a while to get the bubbles out, but don't worry about it, overnight the bubbles will go away. Those of you who've installed the Invica Shield plastic protectors will find this easy.

If you don't like the position of the lens, you can easily remove it and reposition it. Once it dries, it will stay in play indefinitely. I had one in the rear window of my 75 Rabbit and it lasted for years.

8x10 is a good size. The lenses also come in 6x8 and 11x14. The smaller one would work, although it wouldn't be as wide, but the largest one is more than you need and if you trim off too much, you lose some of the wide angle-ness of the lens.

The lens will not work in the upper rear window because the slope of the glass is too steep; your line of sight needs to be pretty much at right angles to the surface of the lens.

You can get these lenses at any RV outlet. Some auto parts places probably carry them too. Mine cost me 12 bucks and I think it actually works better than the camera and is fail safe.

Does it help parallel parking? Very much so. In spite of being on the driver's side, the rear view covers the width of the car. What you see at the bottom edge of the lens is approximately 3 feet from your rear bumper. You can judge accordingly. Handily enough, the window heater wires are also handy distance measuring lines. An object lined up with the first wire up from the bottom is approximately 8 feet from my rear bumper. When I parallel park now, I know that when the front end of the car behind me drops out of view in the lens, that I have about 3 feet to go. It's startling how different the distance looks without the lens and how much harder it is to guestimate the distance while backing up.

Bob