Wednesday, October 31, 2012

COIN Collection/Selling: VALUE of cleaned and unclean coins


from goldismoney2.com
To the general public, it would seem logical that a bright and shiny coin would be favored by coin collectors- favorability of course is equated with value. This may be true to a certain extent if a coin is "naturally" bright and shiny because it was well preserved or just came from the Mint.  However, if a coin is "unnaturally" bright and shiny because it was dipped in vinegar and baking soda or scrubbed with an abrasive like toothpaste, then coin collectors will shy away. 
hfrom kidsactivitiesblog.com
What's also true is that collectors prefer coins that display normal, natural color. In coin collecting, numismatists tend to take the "old, fine wine approach"- they value and appreciate coins that show their age.


Considering above and its impact to the coin value, the ready answer to the usual question if one should clean a coin and how normally leads to one answer: "Don't clean your coins!" Why? Its because experts can tell if a coin has been cleaned, like:  
1.  unnatural coin colors.Examples: cleaned pennies take on an unnatural orange color or show streaks or blotches of color; 
'Worn' Hibernia Half Penny.The unnatural orange
color indicates cleaning, which lowers value. 
Silver coins take on uniform grey colors otherwise unnatural for silver coins, etc. 

 2. unnatural, uniform coin reflectivity usually with heavily cleaned coins 

Values For Cleaned Coins vs Uncleaned Coins.
What are cleaned coins worth, compared to uncleaned coins? As there is little science in valuing either, judging a cleaned coin’s value are mostly based on eye appeal- how "nice" the coin look. There is no "rule" for such values and pricing and it is often done on a case-per-case basis. Sample valuations mentioned below are more common price discounts offered from dealers  based on their subjective assessment of a coin's eye appeal.

One of the biggest problems with rare coins is cleaning often with steel wool, silver polish, acid, or
 other similar destructive processes. You can't fix eye appeal or damage by cleaning your coin.

1. Abrasively cleaned with scratches or hairlines with lost luster will rarely be worth anything more than half its original, uncleaned value. 
2. Lightly cleaned (not scratched and minor evidence of impaired luster) may be reduced in value by as little as 10% or as much as 30%.

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Wednesday, October 24, 2012

Banned Volkswagen Ad/Commercial

Here's  a break from our usual classic VW beetle fair...

Check out this Volkswagen Polo commercial/ad which somewhat became controversial. Personally, I find it funny but of course it may touch on certain sensibilities....Come to think of it, that's what ads are mostly about, right- shock value?

What do you think?


Tuesday, October 16, 2012

Volkswagen Vintage Ads 2

Paul Newman's Insane 300hp VW Bug
 Paul Newman, the late-great movie star, possessed an independent streak that contributed to his
aura and celebrity appeal,  thus in the wake of initial Hollywood success of the early 1960s -starting with 1963's
 he went and
got himself not a new Cadillac convertible, Rolls, or Ferrari... but a cherry-red
 1963 VW Beetle Convertible.
He was soon recruited by VW's agency in the US to pose in ads with his car-
  a no-brainer for Volkswagen. 
1979 Volkswagen Rabbit print ad featuring Wilt Chamberlain.
An original vintage advertisement in black and white.

Karmann Ghia Coupe

You'd have to be some kind of car sleuth to know that concealed underneath
the Karmann Ghia's beautiful exterior is the heart of a Volkswagen. 
The Harlequin Volkswagens seem to have drawn their inspiration from this vintage Volkswagen Ad. Volkswagen of America won numerous awards for their Cheeky Advertising throughout the 60s, and this was but one of those ads.
IT READS: 

What is it?
Glad you asked. It’s a Volkswagen Station Wagon. Don’t pity the poor thing. It can take it. It can carry neatly a ton of anything you can afford to buy. Or 8 people (plus luggage) if you want to get practical about it.
And there’s more than one practical consideration. It will take you about 24 miles on a gallon of regular gas. It won’t take any water or anti-freeze at all; the engine is air-cooled. And even though it carries almost twice as much as regular wagons, it takes four feet less to park.

What’s in the packages?
8 pairs of skis, the complete works of Dickens, 98 lbs. of frozen spinach, a hutch used by Grover Clevland, 80 Hollywood High gym sweaters, a suit of armor, and a full sized reproduction of the Winged Victory of Samothrace.


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Friday, October 12, 2012

Volkswagen (VW) Beetle Basics: Additional Gauges- Voltmeter and Ammeter

Additional Gauges- Voltmeter and Ammeter:

In addition to the Oil Temperature gauge and the Oil Pressure Gauge I mentioned in my previous posts (VW Beetle Basics: Additional Gauges- Oil Temperature GaugeVW Beetle Basics: Additional Gauge- Oil Pressure Gauge) here are two other additional and related gauges I added to my VW beetle:
VDO-190031 Ammeter, 60AMP

VDO-332041 Voltmeter, 8-16V










Voltmeters measure voltage, whereas ammeters measure current. Both are based on the galvanometer which is a device used to detect small currents. Galvanometers that are calibrated to measure currents of different amounts are called ammeters. When they are modified to measure voltages, they are called voltmeters.

Voltmeter

These are the additional gauges in my 1973 VW Beetle
The upper two are the Oil Temperature and the Oil Pressure Gauges while the bottom one is the Voltmeter

A voltmeter gauge, unlike the ammeter, is very inexpensive. It allows at a glance an assessment of the bug’s electrical/charging system performance. The voltmeter shows you the condition and function of the entire electrical system which includes the charging system and that of the battery. It is also handy in monitoring the function of the other electrical accessories such as the lights, signals, wipers, etc.
A 14-14.5 volts from your charging system (generator/alternator) is ideal to get your battery to charge correctly. A voltmeter will give you this information. If the reading is in the 13.5 to 14.5 volts range it indicates that the battery is fully charged and that the generator/alternator output is matching system demands. If over 15 volts your generator/alternator is probably over charging and you are going to get smoke soon... If under 12.5 volts with the engine not running, battery may be weak; if the engine is running, it’s indicates that the generator system may be failing.
A volt meter is much easier to install. All that is required is to connect it to ground and to a "hot" line that is switched by the ignition key. No massive power is involved which may not cause a big problem if the circuit fails.

Ammeter

An Ammeter gauge measures the flow of current to the battery. It is a very good indication of the function of the charging system as well as the draw that various accessories put on the battery. If you want to know how far your house battery is down and how long it might take to charge, an ammeter would help. It gives you a better idea of your battery’s ability to hold a charge. It will also tell you if something is draining your battery when everything is off.

This gauge though must pass all of the current to the battery which means that the wiring to and from it must be heavy- 8 gauge or better. With the gauge in the dash of your Beetle, it means that you must run a length of this heavy wire all the way from the battery to the dash and back. With an ammeter gauge, be aware of the wiring requirements. The current path must be very solid making sure that the connections to the gauge are protected from shorts.

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Tuesday, October 9, 2012

Volkswagen (VW) Beetle Basics: Additional Gauge- Oil Pressure Gauge

The simplicity of the Beetle in form and function can be easily seen in the instrument cluster offering only the very basic gauges. As much as I wanted to maintain the pristine workmanship of the classic VW, as a practical car newbie not completely confident with basic car engine knowledge and maintenance in general, any additional information I can get from my engine to hopefully anticipate road disasters would help take the edge off my deficiencies. In addition to the Oil Temperature gauge I mentioned in my previous post (VW Beetle Basics: Additional Gauges- Oil Temperature Gauge) here is another  gauge I added to my VW beetle over the years:


Oil Pressure Gauges (Electrical)
An additional oil pressure gauge runs a very close second to an oil temperature gauge in terms of importance. With the classic setup without an additional oil pressure gauge, when the "Oil" light (right light green in earlier models, red in later) on the classic speedometer flickers at speed, one is advised to STOP as this may indicate low oil condition. The thing is this green "idiot" light is supposed to come on at around 7 psi and are more often than not NOT that reliable. Knowing what your oil pressure is at different engine conditions (hot, cold, idling, running at different rpms, etc.) can give you an excellent indication of the health of various engine systems. The key is to establish baseline pressure readings when your engine is healthy, and then be aware of any changes you see over time.


In general, one should be aware also on what determines oil pressure. At lower engine speeds, oil pressure is limited by the clearances between the various bearings and journals.
checking for crankshaft journal wear
As the space between the crankshaft bearing journals and its bearings increases through wear, oil pressure will be lower because oil can flow out of the space more easily. The same is true for the journals on the big ends of the connecting rods. Thus, everything else being equal, low oil pressure can indicate worn bearings. 

There are other factors that affect oil pressure. When the oil is colder, it has a higher viscosity (it's thicker), which means it cannot slip through the bearing clearances as easily. Oil pressure at idle is usually a bit higher when the engine is first started up. On some cars, low oil pressure at idle when the engine is hot is quite normal. Oil flow may be perfectly adequate, even though the pressure is low. 

It stands to reason that thinner (lower-weight) oil will indicate lower oil pressure than a thicker oil, at least at idle and moderate engine speeds. Lower pressure caused by changing to a lower-viscosity oil may not indicate a problem, provided it is not being overheated. If the oil is thinner because it is breaking down, too hot, or diluted with gasoline from an over-rich mixture or worn rings, you should change oil at once and correct the problem. 

Potential Causes of Low Oil Pressure:



  • Low Oil Level - oil pressure dip during a hard corner or under sharp braking. Stop at once and top up the oil, or you can seriously damage your engine.
  • Diluted or Worn-Out Oil - (see above).
  • Damaged Oil Pan or Pickup Tube - may be due to scraped or banged oil pan.
  • High Oil Temperature - generally not a big factor, but if you're pulling a trailer or running flat out in really hot weather, your oil can run well over 250 degrees F., and oil pressure will be lower.
  • Worn Engine Bearings - (see above). A further indication can be a heavy knocking under engine load (main bearings) or a lighter knocking (connecting rod bearings).
  • Worn Oil Pump - This could be anything from a slight reduction all the way to catastrophic failure.
  • Dropped Crankshaft Plug(s) - These metal plugs fill the holes where the factory drilled oil passages in the crankshaft. If one falls out, oil pressure will suddenly drop across the board. You can still drive (slowly) to get home, but the plug(s) will need to be replaced.

High Oil Pressure:

High oil pressure is not generally a concern but if pressure suddenly increases, there may be a problem with the pressure relief valve. Switching to a higher-viscosity oil will also show higher readings. In choosing oil weight, it's best to follow the manufacturer's recommendations for the season and type of driving.

Types of oil pressure gauges.

Mechanical gauge
Oil Pressure Gauge and Sender



  1. Mechanical gauge- oil pressure signal is sent via a small tube to the gauge. Inside the gauge is a hollow curved spring called a Bourdon tube. As pressure increases, it tries to straighten the spring attached to a linkage and arm which in turn is connected to a needle which sweeps a calibrated face giving you your reading.
  2. Electrical gauge is comprised of an electro mechanical sending unit, an electrical circuit and an electrically operated gauge. With this system, a voltage source is sent to the gauge through a coil which interfaces with a needle arrangement that moves according to the current flowing through the coil. The current is controlled by the sending unit which is screwed into an oil galley in the engine block. There are different sensing arrangements but the most common is a variable resistor which allows a calibrated amount of current and is calibrated to the gauge face which gives the readings.
These are the additional gauges in my 1973 VW Beetle
The upper two are the Oil Temperature and the Oil Pressure Gauges while the bottom one is the Voltmeter


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Volkswagen (VW) Beetle Basics: Additional Gauges- Voltmeter and Ammeter

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Volkswagen (VW) Beetle Basics: The Speedometer and Warning lights for Idiots…













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Thursday, October 4, 2012

Volkswagen (VW) Beetle Basics: Additional Gauges- Oil Temperature Gauge

From my previous post on the "Volkswagen (VW) Beetle Basics: The Speedometer and Warning lights for Idiots…"  the simplicity of the Beetle in form and function can be easily seen even in the instrument cluster offering only the very basic: the  Speedometer itself, Odometer, turn signals, fuel gauge, high beam light indicator and the two warning idiot lights (gen/Alt and the oil indicators). 
Volkswagen Beetle 1971-1979 from volkszone.com
Any VW purist can easily defend the austere instrumentation as simplicity that worked as it served its basic purpose well.  As much as I would want to maintain the pristine workmanship of the classic VW, as a practical car newbie not completely confident of basic car engine knowledge and maintenance in general, any additional information I can get from my engine to hopefully anticipate road disasters I believe would help take the edge off my deficiencies. Here are the gauges I added to my VW beetle over the years mostly due to consultations with my VW buddies:

Oil Temp Gauge 
VDO 310901 Cockpit Style Cylinder Head Temperature Gauge
 2 1/16" Diameter, Black Dial Face
The stock Beetle engine has no temperature indicator. Any old school VW enthusiast though can very well tone down your concern by offering bug built-in alternatives to what is a very basic indicator requirement for all cars today which can range from the practical to the theoretical. One very practical “indicator”  is the oft repeated guide that if a Beetle engine is truly overheated, you will not be able to touch the dipstick handle for even a couple seconds, without burning you fingers.   Yet the basic instrument cluster itself is enough for the standards of some VW purists who will argue that an overheated engine would force one of the two "idiot" lights to come on. Theoretically, an overheated engine's oil would run thin causing pressure to drop enough at idle that the green light would come on. With my newbie fear of not wanting to wait for my oil to thin out to know that I have a problem, I decided to go with an additional gauge to help me anticipate this potential issue. 
VDO Oil Temperature Gauge Kit (with Sump Sender)
In non technical terms, an oil temperature gauge is a simple electronic device that uses a temperature sensor usually housed in a brass fitting attached to some part of the engine whose heat would represent oil temperature.  It should be noted though that the primary purpose of the temperature gauge is not to tell you exactly in degrees Centigrade/Fahrenheit what the temperature of your engine oil at a given time but rather to identify changes in temperature. As you get familiar with the normal operating temperature ranges of your VW through the use of the gauge (in hot and cold weather- they are different for the air-cooled engine) the more important information the oil temperature gauge should give you is NOT exactly the precise numbers itself but to answer the question: “is my engine is running hotter than normal?” With a more graduated gauge as a guide, you can even start “playing” around with it in relation of course to the VW cooling system mentioned in my previous posts (VW engine cooling system components.VW Idiosyncrasies:Overview of the VW engine cooli...VW Idiosyncrasies: How an Air-cooled Engine Works) on cooling flaps, cooling tins, Fan shroud and thermostat, etc. and potential other temperature related accessories like oil sump plate, full flow oil system, etc.   


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Tuesday, October 2, 2012

How to Ruin Your Coin Collection


I came across several posts on the proper way to store and care for your coin collection- either to maintain as a collection or for eventual  trading. I believe the short and simple tips below which are commonly sourced from the net are a MUST to know for newbies in this craft. Think of coin collecting as an investment you should protect  so.....

DON'T DO THE FOLLOWING: 

1. Clean Coins

from coins.thefuntimesguide.com
Cleaning or polishing your coins will do more harm than good. Doing so can strip the coin of its toning which is a natural result of oxidation with the coin's exposure to air. Take note that toned coins are worth more than a cleaned or stripped ones. Cleaning also can result to a coin's lost of any remaining mint luster making the coin appear harsh and unappealing with microscopic abrasions- all of which can lower its grade.

But, if you really must clean them (for freshly dug-up detector find coins for example) , clean coins safely.

2. Touch Coins- with your Bare Hands.


Our fingers contain oils, acids and microscopic dirt that can adhere to the coins which can cause discoloration, stains or gross and/or microscopic scratches. Coin contact with your bare fingers can cause the damages mentioned especially for higher grade coins, mint state and proof coins .  DO: Wear cotton or latex gloves when handling coins which should be held only by the edges.

3. Spit on Coins

This can be directly spitting on it in an attempt to clean it but can also be indirectly through bits of saliva  when you chat while handling coins.Saliva contains many enzymes that can cause difficult to remove spotting and discolorations which can easily ruin your precious uncirculated and mint-state coins .

4. Break Their Holders

Never remove coins from coin holders or coins that have been slabbed. Mint set and proof set coins will greatly decrease in value once removed from the mint-issued holders they come in. Coin holders with the box and literature (if any) are considered a "set" which should be kept intact and pristine. Slabbed coins are worth a premium in their protective cases.

5. Expose Them to Acid


Cardboard coin holders
Slab Coin holder

Acid in this context is not the liquid chemical itself found in cleaning solutions but from what appears to be innocuous coin storage materials such as paper based containers (envelopes, paper wrapping materials, cardboard  boxes, paper labels, etc.) and certain coin plastic containers (PVC-based plastic flips , holders,boxes). Common paper materials are acidic by nature and  acid by products of plastics can be released around your coin over time. Same as the cleaning materials, acid from paper can cause coin spotting, discoloration, degradation of coin surfaces and can promote oxidation (toning). Coins stored in food-grade plastic containers or in soft, pliable coin flips will eventually develop a slimy green coating on their surfaces which can damage them permanently. It is recommended that only acid free paper and plastic supplies should be used in coin collection.

6. Expose Them to the Elements

Coins stored in the attic or basement can expose them to extremes of temperature and humidity that will promote their oxidation. This impacts not only the coin itself but will also hasten the  breakdown of the storage storage materials mentioned above (flips, paper and cardboard, plastic containers, etc.). To best protect your collection it should be stored in a dark, dry, temperature controlled environment such as a safe deposit box or specialized coin cabinet..
safe deposit box or specialized coin cabinet
from coincommunity.com


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Monday, October 1, 2012

BASIC Digital Photography Glossary: Q to Z

BASIC Digital Photography Glossary: Q to Z

Photography Word Cloud Concept on a Blackboard 
For me to have a better understanding of this hobby before I try it out (and buy expensive equipment!) I went on with my usual research to learn more about it. The best way to start is to have a ready reference for the usual terms I have already encountered and surely will encounter more.

This glossary is lifted mostly from http://www.dummies.com ,  http://www.thephoblographer.com/ and other sources which I found very useful. The list is mostly from the dummies.com as I believe this glossary is a more concise and compact reference for beginners likes me. I added some definitions from other sources also to some terms to try to simplify it further.

Q

quick-connect plate: A mount on some digital cameras that allows you to easily attach the camera to a tripod.
Most tripods include a quick-connect plate like the one shown in this figure.

R

RAM: Random Access Memory. Your computer’s system memory.

RAW - Many photographers will choose to shoot their images in RAW format. This is essentially an unprocessed image.
Choosing RAW format in Canon DSLR
Shooting in RAW allows the photographer a broader range of flexibility after the shot is taken. It is almost like an undeveloped negative. Images captured in JPG format have been processed and aren’t as easy to manipulate later. 
Think of it this way:
     Film: Negative -> Print
     Digital: RAW -> JPEG
Not all cameras have RAW shooting mode. All DSLRs do though.

rangefinder camera: A type of camera that includes a focusing mechanism which allows the photographer to measure the subject distance and take photographs in sharp focus.

rear curtain sync: An electronic flash synchronization technique in which the flash fires only when the second (rear) curtain of the focal plane shutter begins to move at the end of the exposure.

red eye: An effect from flash photography that appears to make a person or animal’s eyes glow red. Caused by light bouncing from the retina of the eye.

resolution: A term used to describe the capabilities of digital cameras, scanners, printers, and monitors; means different things depending on the device.

RGB: The standard color model for digital images; all colors are created by mixing red, green, and blue light.

rule of thirds: A way of mentally dividing your picture horizontally and vertically into thirds, then placing important subject matter where these lines intersect.
Rule of Thirds: See how the bicycle and man are positioned on the intersection points

This is the basic idea of composition. It is essentially dividing the image up into three horizontal and vertical sections.
These lines are available to see on most point-and-shoot cameras. On a DSLR, you can either change the filter in your eyepiece (viewfinder) or imagine them. Depending on who you ask (and I’ve been taught both ways by my mentors and in internships) you can either use the lines to ensure that your subjects (those you are photographing) are not centered or that they are centered.

S

samples per inch (spi): The number of pixels both horizontally and vertically in each squared inch scanned by a scanner or recorded by a digital camera.

scene modes: Digital camera’s special picture-taking modes that are designed to automatically set all the available focus and exposure controls for a certain type of subject matter.

self-timer: Mechanism that delays the opening of the shutter for some seconds after the release has been operated.

Shooting Speed/Mode- This determines how many pictures (or exposures) your camera will take when the shutter is pressed down.

     Single- When the shutter is pressed it will take one picture. To take another picture, you need to press 
                  the shutter again.
    Continuous- When the shutter is pressed and held down it will keep taking pictures until the card fills up 
                  or the processor can’t write anymore photos to the card.
On your camera, this is typically characterized by the three rectangles stacked on top of one another.
shoulder stock: Devices modeled after rifle stocks that brace the camera lens into your shoulder, thus helping hold it steady.

shutter: The device in a camera that opens and shuts to allow light into the camera.

shutter button: The button on your digital camera that you press to take a picture.

shutter speed: The length of time that the camera shutter remains open, thereby allowing light to enter the camera and expose the photograph.
Photography lesson #4 – Shutter speed
 a great resource from miketurner-photography
The shutter speed is the actual time that the shutter is open to allow light to hit the sensor. Shutter speed is usually measured in seconds. The smaller the number is, the shorter the shutter will be open. Longer shutter speeds are used for low light conditions such as shooting at night, or can give the effect of fast motion making objects appear blurry.

shutter-priority autoexposure: A semi-automatic exposure mode in which the photographer sets the shutter speed and the camera selects the appropriate aperture.

single auto-focus: A setting in which the camera focuses on a single object.

slave: An accessory flash unit that supplements the main flash, usually triggered electronically when the slave senses the light output by the main unit.

SLR (single-lens reflex) camera: A type of camera that includes interchangeable lenses, manual focus and exposure controls, and connections for an external flash.

snoot: A tube-like device that focuses the flash’s light to a very small area.

soft box: An attachment that mounts on the head of the flash and extends out about 6 to 8 inches, with a frosted white panel at the end, which softens the light.
spot metering: Metering mode that bases exposure on light in the center of the frame only.

stitch: Creating a panorama from multiple images by overlapping those images.

strobe: Another name for an electronic flash unit, especially when it's used as the only source of illumination.

subcompact: A type of digital camera that's small enough to fit comfortably in a shirt pocket.

swivel mount: The part of a tripod to which the camera attaches that you can move to some degree.

sync connector: A special bracket that fastens to the tripod socket on the bottom of a digital camera; allows you to connect an external flash to your camera.

T

table-top tripod: A lightweight tripod with shorter legs than a standard tripod. Also called a mini-tripod.

telephoto lens: A lens that magnifies an image.
The telephoto lens is used in taking photos that are
far away, allowing more detail to be shown in the distance.
TIFF: Pronounced tiff, as in a little quarrel. Stands for tagged image file format. A popular image format supported by most Macintosh and Windows programs.

time-lapse: Taking a picture at specified intervals to capture an event occuring over a long period of time.

tolerance: The range of color or tonal values that will be selected with a tool such as an image editor’s Magic Wand, or filled with paint when using a tool such as the Paint Bucket.

tripod: A three-legged supporting stand used to hold the camera steady. Especially useful when using slow shutter speeds and/or telephoto lenses.

U

ultra-compact: A type of digital camera that's the size of a credit card, with a depth of less than 1 inch, that fits comfortably in a front jeans pocket.

underexposed: When too little light hits the camera’s film or image-sensor array, creating an image that’s too dark.
upsample: Add pixels to a digital image.

USB: Stands for Universal Serial Bus. A type of port now included on most computers. Most digital cameras come with a USB cable for connecting the camera to this port.

V

VGA resolution: Video Graphics Array resolution. A display of 640-x-480 pixels with 16 or 256 colors.

video card: A computer adapter card used to manage the display on the monitor.

viewfinder: The device in a camera used to frame the image.

vignette: To add dark corners to an image; often produced by using a lens hood that’s too small for the field of view or generated artificially by using image-editing techniques.
Vignetting
W

white balancing: Adjusting the camera to compensate for the type of light hitting the photographic subject. Eliminates unwanted color casts produced by some light sources, such as fluorescent office lighting.

wide-angle lens: A lens that has a shorter focal length and a wider field of view than a normal lens for a particular film or digital image format.
Wide angle lenses are defined as lenses with focal lengths that are less than 50 mm most commonly used for
landscape photography. Wide-angle lenses are good at focusing on everything rather than one small part of a scene.

Z

Zip drive: A type of removable storage device known as a super floppy drive; store information on Zip disks.

zoom lens: A lens that can change focal lengths at your command to provide more or less magnification of the image.
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