In general, the prescriptive power of a contact lens will be somewhat less nearsighted than eyeglasses. So in most simple words, the power of a contact lens will be lower than the eyeglass prescription. Reason being the distance of the … Continue reading →

The total magnification of a low power objective lens combined with a 10x eyepiece lens is 100x magnification, giving you a closer view of the slide than a scanning objective lens without getting too close for general viewing purposes. Figure … Continue reading →

Which, the brand hopes, will reverse the tide: according to research conducted by SK-II scientists, our eyes become 20 percent smaller over 15 years, beginning from our mid-20s. The biggest cause of this shrinkage is the lack of firmness around … Continue reading →

More videos on YouTube Insert your lowest-power eyepiece into the telescope and tighten in place. Look through the eyepiece. Turn one of the two knobs to the side or below the eyepiece–first one way, then the other–until the object is … Continue reading →

Grey Grad filters work by evening out the exposure difference between an over bright and over dark areas of an image, bringing the difference in contrast closer together. What is ND400? ND400. ND400 absorptive neutral density filters have an optical … Continue reading →

The largest-focal-length eyepiece you can use with your telescope is easy to calculate: multiply the focal ratio (the focal length of your scope divided by its aperture) by 7. For example, your Newtonian scope is f/5: the largest-focal-length eyepiece you … Continue reading →

A 70-200mm zoom, for instance, is a great portrait lens because every focal length it offers works well with faces. It’s the lens I use most often for head-and-shoulder portraits, typically standing about 8 feet from the subject and using … Continue reading →

All the evidence is that ‘SvBony’ is a front for a redistribution network. Basically a marketing ploy. They must have few overheads to be able to market products at such low prices. It’s interesting that they’re Hong Kong based. Where … Continue reading →

Aperture is a hole in the lens that controls how much light gets into your camera. It’s one important element of the exposure triangle, along with ISO and shutter speed. Aperture also affects your depth of field, which is defined … Continue reading →

Arm: The part of the microscope that connects the eyepiece tube to the base. What part of microscope is ARM? Arms – This is the part connecting the base and to the head and the eyepiece tube to the base … Continue reading →

Mobile device overuse increases the risk of myopia (short-sightedness) “Playing with handheld devices constitutes near work, which has been shown to be associated with myopia (commonly known as short-sightedness),” says Dr Tay. Can phones cause myopia? When our eyes spend … Continue reading →

There is an illuminator built into the base of most microscopes. The purpose of the illuminator is to provide even, high intensity light at the place of the field aperture, so that light can travel through the condensor to the … Continue reading →

Bronica SQ-Ai medium format Canon 5D Mark III Canon EOS 1D Canon Rebel T5i Nikon D3S Nikon D4 Nikon D800E Rolleiflex TLR medium format Sony A99 Wista 4×5 field camera. How much does Nat Geo pay photographers? National Geographic Photography … Continue reading →

How do you use a handheld telephoto lens? Tips on Photographing Hand-Held with Telephoto Lenses Angle the Left Side of Your Body Towards Your Subject. Form a Solid Support Triangle. Adjust the Angle of Your Arm Extension. Control your Breathing. … Continue reading →

And while all iPhone 12 models have a wide and ultra-wide lens, it’s the telephoto lens that’s unique to iPhone 12 Pro and iPhone 12 Pro Max. The telephoto lens is handy when you’re at a larger event like a … Continue reading →