1. Myths & Lies…

2. 2 Table of Contents… P. 3“Always use a clear glass filter on lenses to “protect” them.” P. 9“To clean a lens: Fog it by breathing and then wipe w/ your T-shirt.” P. 10“You should clean your lenses often.” P. 12“The brand of camera is very important.” P. 13“If you see “spots” on your digital images, you need to:” P. 15“It’s very important to set the “DPI” specification in all your photos.” P. 16“To get the sharpest images, stop down your lens as far as it will go.” P. 17“You should strive to get perfect images straight out of the camera.”

3. “Always use a clear glass filter on lenses to “protect” them.” When you buy a camera, the dealer is very likely to have a picture taped under the glass counter to scare you into buying a “protective” UV filter. Here are examples: Notice that these two examples were dropped on the EDGE of the filter. If you poke something into the front of the glass of the filter, this is what happens [below]: 3

4. The entire glass filter shatters and the small, sharp glass shards are forced into the front glass element of the lens by whatever object encroached. This destroys the lens, because there is a thin, antireflective coating on each glass surface of a good lens. When that coating is removed, even partially, the lens will exhibit flare and ghosting. A UV [or skylight] filter is made with a very thin glass element; often as thin as 0.010”. A 0.010” glass filter doesn’t protect anything! This thinness is important to eliminate vignetting w/ zoom lenses at their shortest [WA] focal length. The metal part of a filter is also very thin, for the same reason. The metal is either Aluminum or brass; both are very soft. They bend easily and when they bend, the threads are almost impossible to use; often the mating threads on the lens are damaged when removing a bent filter. The front part of a lens is much stronger than a filter. Putting a filter on a lens, expecting “protection” is like sticking a Kleenex tissue in front of your face during a fist-fight! Filters and Kleenex tissues are for “filtering”, not “protection”. You especially want to avoid the $20 UV filters that unscrupulous stores sell you. They are made in China for about $2. The store has a BIG profit on these type sales! If you simply can’t believe that you don’t need a filter to protect your lenses, at least buy a good one. Proper brands are Hoya, B+W [Schneider], & Heliopan [Schott]. Hoya unfortunately sells cheap filters too, but their expensive ones are great. 4

5. A good filter [one with quality threads and multi-layer AR coatings] is expensive. A cheap [$20] filter will ruin the expensive, good optical properties of your camera. An expensive {$100-$200] filter often costs as much as the lens! You should never “invest” more than 20% of the cost in a protective device. And a skinny little UV filter doesn’t offer any protection. A filter does the opposite; it makes it more likely that a lens will be damaged. Only use a filter when you absolutely have to! There is a lot of information on-line about this protective filter issue. Much of it is poor and wrong. This video is OK. The guy in it, Steve Perry, is not very “scientific”, his “test fixture” is laughable, and his procedures are often bad. In spite of this, he does expose some of the insanity surrounding the issue: http://petapixel.com/2015/08/31/photo-mythbusters-how-much-do-uv-filters- actually-protect-your-lenses/ 5

6. Only a few filter types are needed for a digital camera. You need a circular polarizing filter and a couple of neutral density filters. You DO need a UV/Skylight filter for times when there is blowing sand and you would rather not sandblast the front lens element! SO, what do you do: Leave the lens cover on until just before every shot? Nope. You use a lens hood! It should be made of strong plastic [polycarbonate] not rubber or Aluminum. It should attach to the lens body where it doesn’t move [because that’s stronger; many modern lenses have internal focusing and this is strongly recommended]. You should leave the lens hood on every lens 100% of the time, even when it’s in your camera bag. If you say that the lens hood makes the lens too big to fit your bag, then you screwed up and need to get another bag w/ more room! If you say that you can’t [easily] put the front lens cover on the lens when the lens hood is installed, then you should put that lens cover in a drawer. You don’t need a front lens cover if you leave the lens hood on 100% of the time. 6

7. 7 Even an expensive filter will degrade the images your camera takes! Any external piece of glass will increase the flare produced by a lens. What is flare? This is flare: Lenses create flare, even w/o an external filter, but it seems that two flat, parallel optical surfaces are especially bad. In this example, a hood would not help reduce the flare. But if the sun was outside the frame, a hood might have helped to keep direct sunlight off the front of the lens. A modern, plastic lens hood will bend and absorb much of the shock if the lens is dropped, lens down. Even if it cracks, it will absorb much of the impact and usually save the lens. A lens hood won’t save a lens from a BB [but neither will a UV filter]. A tree branch may reach inside a hood and scuff the AR coating on your lens, but not as badly as hundreds of shards of glass driven into the lens by that branch!

8. Here is an example where the sun was well off axis, but still created a lot of flare: This picture would have been improved by having a lens hood! In addition to creating flare, filters also cause fogging of the image with light, which reduces the contrast. Here is an example: 8

9. Even with a lens hood, lenses can have issues w/ flare. One reason is that a hood for a zoom lens has to be designed for the shortest focal length, thus when using the longer focal lengths of a lens, the hood is not very effective. This is one reason really serious photographers use single focal length lenses [called “prime” lenses]. If you notice flare while composing a picture [you can see it through the viewfinder], one cure is simply to put your left hand up to shield the sun from the lens; just don’t get your hand in the field of view. 9 “To clean a lens: Fog it by breathing and then wipe w/ your T-shirt.” False! Breath has proteins which will coat the glass. Your T-shirt is not clean.

10. “You should clean your lenses often.” The truth is that you almost never need to clean your lenses! A small amount of dust on the front of your lens has no negative affect if you leave it alone. When you try to remove it, you generally scratch the lens. The only regular lens cleaning should be an occasional blast from a Rocket Blower. If you get a fingerprint on the lens, then you should clean it, because the oil is slightly acidic and will etch the AR coating. The first thing you should do when you get a finger print on a lens is to check to be sure that you have a lens hood installed; if not, put a hood on. A lens hood will keep most fingers away from the front glass surfaces of a lens. 10 AND, don’t blow on the lens w/ your mouth, in spite of the many TV ads that show this being done! Your breath has many things other than air in it! That stuff doesn’t blow off, so you are forced to do a wet cleaning.

11. When you absolutely have to clean a lens, do it right. 1.Blow any dust off with a Rocket Blower. Don’t blow on lenses with your mouth because you will blow things other than air and water. They will stick and make it worse! 2.Under strong light, look for any remaining particles. If any are found, use a lens brush to dislodge them and check again. Do a final Rocket Blower dust off. 3.Take a lens cleaning paper and dampen it with one drop of lens cleaning fluid. Don’t put lens cleaning fluid [methanol] directly on a lens! 4.Fold the paper twice; don’t crumple it. 5.Wipe the lens using a circular motion, starting at the center. If additional wiping is needed, use a clean surface of the paper [you get 4 attempts with each piece of cleaning paper]. There is no objective evidence that a small amount of dust on the front of a lens has any affect on the image! All you OCD Porsche folks, leave lens dust alone! Go wash and wax your car or something. 11

12. “The brand of camera is very important.” The truth is that the brand is not too important, but there are differences; probably not the ones you were expecting though. In 2015, it’s actually difficult to buy a truly bad camera. It’s much easier to be a bad photographer w/ a good camera. SO, who makes the best [even if the differences are small]? 1.dSLR = Nikon, Canon, and Olympus 2.P&S = Canon, Panasonic, & Fuji 3.Mirrorless = Sony, Samsung, & Panasonic But things change, so the best today is likely not the best tomorrow? And opinions differ about what parameters are important in choosing a camera. One often overlooked, but important issue is how a camera fits your hand: In general, Canon makes cameras for small hands and Nikon makes cameras for big hands. Just as when buying shoes, try out the fit of a new camera before you buy. Also be aware that when using a big, long lens, it’s more comfortable to have a large body. Also, a heavy camera + lens is easier to hold steady. If you tire easily of holding the weight, get a monopod. 12

13. “If you see “spots” on your digital images, you need to:” Clean the front of your lens Clean the back of your lens Clean the mirror Clean the viewing screen Clean your glasses Format or replace your media card The truth is that none of these have any affect on “spots” on your images. The true culprit is pollen spores on the IR filter that is in front of your sensor. You need to clean that filter [you can’t clean your sensor because it’s not accessible]. In front of the sensor is that IR filter [sometimes called a “hot mirror” because it reflects long wavelength light away from the sensor so that the sensor stays cool] and the anti-alias filter. Modern cameras have a dust removal system that shakes the IR and AA filters. The sensor is not shaken. Think about why you would not want to shake a sensor? Anyway, when you see “spots” on your pictures, clean the filter in front of the sensor. Note that if you use mostly large apertures, you will probably never see a “spot”, even if the IR filter is covered w/ big pollen grains. Why is that? 13

14. The pollen on the filter is quite a distance in front of the sensor, so in order to get a distinct shadow of the pollen, the light must be somewhat collimated. Collimation is a bit technical, but it sorta means that the light rays must be somewhat parallel in order for a shadow to be observed. Otherwise the shadow is fuzzy and indistinct. A good 7 th -grade science experiment is to find a way to clearly project the dust and pollen spots that are on the filter as shadows onto the sensor. It’s quite simple: 1.Remove the lens. Find a way to make your camera take a picture w/o the lens. 2.Locate an LED light. Turn it on permanently. 3.Place the camera on a tripod. 4.Locate the LED about 10 feet away, pointing at the camera. 5.Turn out the lights in the room [best to do this at night]. 6.Take a picture. If the image is dark, increase the exposure time until the image is semi-bright. You will see dark shadows of anything that is on the filter! To do this w/o the LED light, stop-down the lens to f/32 [or as small an aperture as your lens has] and take an OoF picture of a blue sky. It’s not quite as good as the above, but still will show all but the smallest spots. 14

15. “It’s very important to set the “DPI” specification in all your photos.” It’s hard to believe that there are people who spread this crap. I’m sure it’s caused by ignorance; either that or they don’t have a clue… Each digital photograph, regardless of format, has some data stored along with the picture. The generic name for this data is “EXIF”, but there are other types of data too. Included in the EXIF data is a field named “DPI” [dots-per-inch]. Many printers insist that this field be set to some specific value. The truth is that “DPI” is meaningless. First, it should be “PPI” as digital pictures have pixels, not dots. Next, there is no linear measurement associated w/ a digital picture! It can be printed as big or as small as desired. Most cameras insert a value into this field. “72”, “120”, “300” and “360” are popular values for some reason. They do this just so that it won’t be empty. But it has no affect on how the picture is printed by any printer. If you run into this, just put what ever value the printer asks for in that field. This is almost as dumb as being asked for a 3” x 5” digital picture file! The size of digital pictures are measured in pixels, not inches, feet, or meters. 15

16. 16 “To get the sharpest images, stop down your lens as far as it will go.” In the early 1930’s, some West Coast photographers established a counter-cultural organization, called Group “f/64”. Among those in the group were Edward Weston and Ansel Adams. They were renown for using a very small aperture setting on a large format film camera to create great depth of field. What works on a camera w/ an 8” x 10” film negative doesn’t work on a camera w/ a smaller format. The culprit is diffraction. Look it up in the Glossary. The smaller the aperture, the worse the diffraction effect. The result is that sharpness is highest at a middle f/#. The value of that f/# depends on many factors; to simplify, let’s say that it depends mostly on the size of the sensor; The larger the sensor, the higher the optimum f/#. For a full-frame dSLR, the sharpest aperture is about f/11 For a crop-sensor dSLR, the sharpest aperture is about f/8 For a 4/3 sensor dSLR, the sharpest aperture is about f/5.6 For a 1” sensor ML camera, the sharpest aperture is about f/4.8 For a 2/3” Point & Shoot camera, the sharpest aperture is about f/4 For a 1/1.8” Point & Shoot camera, the sharpest aperture is about f/2.8 For a 1/2.7” Point & Shoot camera, the sharpest aperture is about f/2 For a cell phone, the sharpest aperture is about f/1.4 These are SWAGs, so check with people who understand your specific camera/lens combination or read lens test reports when mounted on your camera.

17. 17 “You should strive to get perfect images straight out of the camera.” This mantra comes from the days when we shot mostly slides. There was no way to edit them later, so we HAD to work diligently to get everything as perfect as possible. And slide film had low Dynamic Range [about 5-6 EV], so it was difficult to capture some images well. Today’s digital cameras are vastly superior to film and the lessons we learned and techniques we used need to be buried. They are different tools that need to be used differently. This belief is rooted in gross laziness! People w/ this belief simply don’t want to do the work necessary to create a truly great image. Inside each digital camera, there is a processing “genie”. It is a simple computer program that accepts the RAW sensor data and changes it to a different format that can be viewed on a screen. This format is called “JPEG”, which is the name of the organization that created it; the “Joint Photographic Experts Group”. This ISO standard has been around since 1992. The purpose of the JPEG format was not excellence, but rather compactness and speed! It uses what is called “lossy” compression. The exact nature of this is arcane, but the result is impressive; the pieces of the digital data thrown away are such that the image is not too badly affected.

18. 18 Also, there are a vast number of different ways to compress the data within the JPEG standard; some are quite good. Sadly, the good compression choices require more time to execute and the resultant files are larger. Digital cameras don’t have big processors, thus when choosing a specific JPEG scheme, manufacturers must compromise. If they didn’t, the camera would be slow to respond [it would still be processing the last image when you wanted to take another]. Thus, the first issue w/ “getting perfect pictures OoC” is simply that the internal “genie” is not very good at rendering RGB images. Most digital cameras have controls. The number of and complexity of these controls varies a lot. But even the simple cameras that don’t have many sophisticated controls still have stored values for these. These default values are chosen by the manufacturer to produce the “look” they think is favored by their customers. Often their customers have no taste or aesthetic sensibility! These default values can, in the more complex cameras, be changed. It takes a bit of knowledge and experience to make these changes. Most users never change anything, even if it is possible. But they need to make changes in some instances.

19. 19 As an example, taking a picture of a distant mountain involves a long air path; often many miles. That air path has dust and moisture which makes the mountains look hazy. There is a simple technique for reducing that haze; simply increase the contrast. However, objects not at a great distance will not be hazy, thus do not need a higher contrast. Most photographers ignore this issue when taking the picture. A few might dive into the menus on the camera and raise the contrast somewhat, seeking a compromise between near and far objects. Then they have to remember to return the contrast setting to the default. Here is an example of an image w/ haze: When I increased the contrast: The mountains are better, but the foreground is too exaggerated and unrealistic.

20. 20 A better way is to use an editor to select different parts of the image and deal with each independently of the others. Here I created 3 areas: The Sky The Mountains and Water The Foreground In treating them each w/o any “global” relationship, I was able to make a picture that “popped”, w/o appearing unnatural. There are other reasons not to believe that a digital camera is capable of magically “getting it right”, as if there is some kind of pure, unadulterated image just waiting to be found.

21. 21 Color is another reason. Why would you let a technician in an Asian country decide what colors belong in your pictures? Have you noticed that different brands of cameras produce different colors? Have you noticed that cheap cameras produce a different “look” than expensive cameras? Which is best? If you have a Canon, can you get it to produce the colors you would get if you had a Nikon instead? Those “genies” in your cameras are using the sensibilities of humans. These humans that write “genie” software are not that special. They are more like the clerk in the WalMart photo department than you would like to believe! Most have no special training in art and perception. They just know how to write embedded firmware. Why would you believe they magically can create a “right” image? The unvarnished truth is: They can’t. To be a “real” photographer, you must take control of your camera, just as taking control is essential to being a “real” driver. Real drivers turn off the computers in their cars when they get on the track! Also, the “genie” in your camera was designed to produce results acceptable to a wide range of customers. Some of those customers are WalMart people!