The Getaway...Crom's build and adventures

Here is one example of what I would call distortion. I have not investigated the why of it, just an observation I've noticed with my camera at certain focal points.

See how the truck appears to be flared out left of center? The roof rack even appears to be out of parallel with cab roof. In reality they are perfect.

Ken, Bruce, or Mike @DVexile @Bman4X5 @tacozord are seeminly all very well versed in photography and could probably tell you why.

 

If you shine a flashlight at a wall straight on, it illuminates a roughly circular patch. Shine the light at an angle, and the illuminated patch becomes increasingly ovoid in direct proportion to the angle. The same thing happens in your camera. At short focal lengths (wide angle) the rear of the lens is quite close to the sensor, illuminating the edges of the sensor at an acute angle, and the images exhibit the characteristic stretching you see in Crom's shot. Single focal length short lenses, known as prime lenses, are highly corrected using aspheric lens elements, and this type of distortion is minimized. The construction of high-ratio zoom lenses involves certain design constraints and compromises that necessarily limit the amount of distortion correction. It's a trade off, and it's why many photographers carry a selection of prime lenses rather than relying on one or two multi-element zooms.

 

Adding to what @Bman4X5 said there are two forms of "distortion" at play in most photographs although only one is formally referred to as "distortion" while the other is really a choice in "projection".

As Bruce already mentioned factors in the design of a lens can result in a lens aberration referred to as "distortion" in which a photograph of a rectangle with its center at the center of the photograph ends up with curved sides. The first order effect is either "pincushion" or "barrel" distortion. A quick Google will give you examples. In a modern zoom lens with a very complicated design you often end up with higher order distortions often referred to as "mustache" distortion in which the sides of the rectangle aren't just concave or convex but actually have a wave to them instead. Here is a nice illustration of these kinds of distortion:

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In Crom's camera as with almost every modern bridge camera we see very little distortion in the output. This is not because the lens is distortion free, in fact almost for certain the lens has lots of pincushion distortion at the wide angle end, but because the camera corrects the distortion while creating the JPEG output. Correcting distortion in camera with software is done by almost every modern camera, even most of the interchangeable lens cameras, because it has almost no impact on image quality and leaves the optical designer with more free parameters in which to correct aberrations not so easily corrected in software (e.g. spherical aberration, coma, astigmatism, longitudinal chromatic aberration). Think of this software correction as some extra virtual lens elements without all the trade offs and manufacturing issues of real lens elements using materials that don't physically exist. Lateral chromatic aberration is another aberration typically left to the camera software to deal with.

I think in the example photo the "flared out" effect is not strictly "distortion" at all. Instead this is the result of using a wide angle lens with a rectilinear projection. The "projection" of a lens is how the imaginary 3D sphere the camera is taking an image of the inside of is projected onto the 2D sensor or film. It is exactly analogous to the problem of printing a 2D map on paper of the spherical surface of the earth. When we print a small region of the earth, like a city map, the projection choice is almost irrelevant and every looks "as we expect". This is like the image produced by a long focal length (i.e. telephoto lens). Nothing looks stretched or flared. When we try to make a map of a large region of the earth now we run into stretching and flaring effects as a result of our chosen projection, everyone learning in school that Greenland is not as big as it looks on a Mercator projection map.

Almost all photographic optics are designed with a rectilinear projection and for short focal length (i.e. wide angle) lenses this results in the edges and corners appearing "stretched" or "flared". For extremely wide angle lenses this can start to become undesirable and that is why we find an alternative projection in super wide angle lenses being available, namely "fisheye" lenses which have a spherical projection instead of a rectilinear projection.

In the end this "flaring" or "stretching" is not solvable when you stand very close to your subject with a wide angle lens. You can only make different trade-offs by choosing various "projections" for dealing with the unsolvable problem of the perspective from which you took the photo. If you want to completely avoid it the only solution is to step further away from your subject when you take the photo. This is why portrait photographers stand relatively far away from their subjects, they don't want this kind of "perspective" or "projection" distortion to make the subject's face look funny.

 

Lol man I know you didn't mean it like that I was just being sarcastic. Super clean! I'll read through it!

 

You can buy the standalone via Amazon: http://amzn.com/B00VWCKJVA

 

This is lens distortion. I think @DVexile and @Bman4X5 have pretty much covered it, so there's nothing more to add. But options to correct are to get a better lens or fix in Photoshop.

 

Nice camera! You gotta love view cameras!!!!!!!

 

I applaud you for getting a fire extinguisher!!! Well done.

For me personally, I wouldn't use a dry chemical extinguisher in a vehicle. Instead, I use a clean agent.

More info about types of fires and extinguishers can be found here: http://www.femalifesafety.org/fire-extinguishers.html

Also, this page has TONS of great info specifically regarding use with off-road vehicles: http://www.pirate4x4.com/articles2/tech/2010-fire

 

Huge proponent of Halotron fire extinguishers for automotive use and plan to reuse the in cab mounts I took off a track car that I sold. I still carry a dry chemical fire extinguisher to hand to someone else who needs it and doesn't have their own.

 

I read a good post in a thread on ExPo I think it was that had two different fire chiefs commenting on vehicle fire extinguishers. One of them had a station situated on a hill right above a busy highway and said they responded to more than one vehicle fire a week. The consensus was that as soon as a fire gets hold in a vehicle any reasonably sized extinguisher was useless. You have to stop the fire very quickly to make a difference which means quick access is important. For in cabin fires the source is of course usually electrical and you ideally want a clean agent (usually means BC only) that the driver can access immediately. Dry chem can effectively nearly total a vehicle if sprayed in the engine compartment or under the dash, but obviously just letting a fire burn will total a vehicle too so dry chem definitely better than nothing.

Brakes and transmissions were the most common starting points outside the cabin closely followed by fuel fires. The problem with transmission and brake fires is that the source is very hot and most extinguishers temporarily smother fires but do not remove heat so the fire can restart quite quickly after being extinguished. Fuel fires have the issue that usually there is a fuel leak and so while you might initially extinguish it there is going to be more fuel coming out and presumably the same hot ignition source waiting to ignite it again.

Obviously for camping where we cook with stoves surrounded by a lot of camping gear we have other things to worry about and you could start a roaring class A fire in your camp pretty quickly. A clean agent BC extinguisher ideal for fires in the cabin or under the hood won't be much help for that kind of fire.

Both of them said any extinguisher is better than none and encouraged people to carry something and most importantly know how to use it. Strongly recommended taking a fire extinguisher course from a local fire safety organization or if that isn't available buying a cheap extinguisher just to practice discharging it. Again be aware how messy and corrosive a dry chem extinguisher is if you are going to discharge one for practice.

They also emphasized do not attempt to fight fires that have begun to take hold in the engine compartment. They fight engine compartment fires from forty feet away wearing full protection gear. Even then fire fighters can get hurt. Either you get the fire down very quickly when it is small or you get everyone out and far away from the vehicle. They emphasized almost every modern vehicle contains metals and alloys that can become class D fires once the temperatures get high enough making fighting them quite dangerous.

I've been evaluating what to do extinguisher wise in my rig. At the moment considering a small BC clean agent at the drivers seat and a dry chem ABC in the back much like Crom's. On a related note I have a seat belt cutter and window hammer in the center console.

I like the mounting solution here Nick, I'll have to look at that. Thanks!

 

Thank you to you three gents for your explanations on the lens distortion issue. Very helpful to my understanding.

Thanks Mike! I've read that pirate4x4 article years ago... Good stuff in there. Author makes a real good case for a vehicle fire suppression system.

One takeaway from the article, if an engine fire happened and rig had redline hood tuning struts, the hood could possibly be opened without being burned.... Just an idea.



The fire extinguisher I carry is really for camp duty, but I would use it on my truck if it did catch fire. I have no delusions about it either, for the reasons @DVexile mentioned below.

Also noteworthy is I carry full-time two gallons of water behind the passenger seat.

And separate from those, I usually have one or two around the camp kitchen.

Nice name change! I'm going to have to save for one of the Halotron ones. Very nice indeed!

Welcome.

Great info Ken. Yeah the truth seems that if rig catches fire, most likely it's gonna burn to the ground. Do you ever notice the scorched asphalt on the sides of roads when traveling, evidence of a vehicle fire? It seems like I see them often.

 

I'm a big believer in the blower motor cab filter. I think I have a years worth of crap in mine pictured below.

I bought a 10-pack of TYC filters years ago when my truck was new, and been working through them ever since. I think it was like $30 for the box of ten.

NASTY!!!

Old vs. new

 

I replaced the shit HVAC blower motor resistor last Friday. Thank you @nfs257 , it was indeed an easy fix. I couldn't find a metric socket to fit the tiny screws, but a 7/32 SAE fit just fine.

If your Tacoma is model 2005-2011, you probably have the old part.

The controlling technical service bulletin (TSB) is titled: "HVAC Blower Motor Only Operates On High" and can be found here.



I think I paid $26 and change shipped to my door with Amazon, genuine Toyota part.

 

https://www.tacomaworld.com/threads/diy-washable-cabin-air-filter.90324/

 

Yeah way back when I think it was hard to source aftermarket filters. I think the stealer wanted $60 for the paper.

I followed the DIY thread a long time ago, but it didn't turn out well for me. lol

Then I washed the factory one twice I think. Then I bought the 10-pack TYC ones and have been changing them out every 6 months or so. For only $3 per unit cost, I'm happy. I think they can be had on Amazon for about $6 each now.

 

I have to wash the cabin filter everytime I go off road due to using the ac and high dust lol So the washable is awesome for me.

 

Thanks for the part number on the cabin air filter. Mines due to be changed. I just ordered a pack of 4 for the same price that Toyota wants for an OEM one.

 

All this talk about fire extinguishers. Have you guys heard of Cold Fire? It was news to me when I first heard of it. The videos seemed impressive enough to get me to buy a couple cans (en route). Take a look for yourself. It's a different way to extinguish fires:

http://www.coldfiredirect.com/cold-fire-videos/

The aerosol cans are small enough to keep one or two in the cab without being too cumbersome and the larger containers can go in the bed. Just thought I'd share.

 

Thank you! I saw these about 6 months ago and couldnt find the link again! Or think of the name of it lol

 

I might just order a case if the two cans I ordered work out. Keep some around the house, garage and throw a few in the truck. Handy and small.