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[UV] EL-Nikkor 75mm - 80mm - 105mm for UV? This is a comparison of three EL-Nikkor enlarger lenses for reflected UV photography.

[UV] EL-Nikkor 75mm - 80mm - 105mm for UV?

The candidates are the older EL-Nikkor enlarger lenses: 4/75mm (black), 5.6/80mm, 5.6/105mm (both black/chrome) [click on image to see a larger one] These are UV-VIS differentials to show the possible focus shift (ghost images, white or black depending on direction of the shift: left: 75mm, middle: 80mm, right: 105mm - identical exposure and processing for all. And here the UV-VIS transmission graph of these three lenses. It gets pretty obvious, that the 80mm is the clear winner, not only in terms of lack of focus shift, but also in UV transmission, since it has about double the transmission @365nm than the 75mm EL-Nikkor. No wonder actually, as the 75mm is a Tessar 4-3 design with one glued lens element, whereas the other two are double Gauss 6-4 designs. P.P.S.: the filter thread of that older EL-Nikkor 80mm is 34.5mm, which is pretty uncommon, Rafcamera.com sells a suitable adapter ring.

Photography of the Invisible World: [UV] EL-Nikkor 75mm - 80mm - 105mm for UV? Flowers in uv and false bee vision. - noto. Wild radish (Raphanus raphanistrum) flower in natural colour (left), uv only (centre) and false bee colours (right).

Flowers in uv and false bee vision. - noto

We’re attracted to flowers because of their form, scent, and colour, the very things that attract their pollinators. It’s clear that some colours are associated with particular pollinator groups, like red for birds and blue for bees. However, most pollinating animals perceive a different colour spectrum from us. Humans are unusual—but not unique—among mammals in having three colour receptor genes, which code for opsin proteins whose light reception peaks in the blue, green, and red wavelengths. Some people—more often males than females because of sex-linkage—can perceive only two, usually blue and green. It seems that early mammals were nocturnal and sacrificed full colour vision for eyes that had many more rods, enabling better, but monochromatic, night vision. Viola banksii flower in natural colour (left), uv only (centre) and false bee colours (right).

How do I use it?

Capstone

Burgundy SK Portfolio Book — Brewer-Cantelmo. Theconversation. These days, we’re used to seeing pictures of planets sent back by spacecraft.

theconversation

Some pictures look colourful, others less so. But do they show what each planet really looks like? The short answer to this is “sometimes”, because some planets are genuinely quite colourful. Others are surfaced by rock that is almost entirely grey, and if you come across a picture of these looking colourful you can be pretty sure that the image has been manipulated in some way. Usually it’s a way of exaggerating subtle differences that human eyes are not good at seeing without help. Anyone who has used a smartphone to take photos has probably stumbled upon various options to exaggerate or tone down the colour.

But a camera on a spacecraft rarely sees colours in the same way as the human eye. Using Wide Angle Lenses. A wide angle lens can be a powerful tool for exaggerating depth and relative size in a photo.

Using Wide Angle Lenses

However, it's also one of the most difficult types of lenses to learn how to use. This page dispels some common misconceptions, and discusses techniques for taking full advantage of the unique characteristics of a wide angle lens. 16mm ultra-wide angle lens - sunset near Death Valley, California, USA. Using Telephoto Lenses. You've probably heard that telephoto lenses are for enlarging distant subjects, but they're also a powerful artistic tool for affecting the look of your subject.

Using Telephoto Lenses

They can normalize the size and distance difference between near and far objects, and can make the depth of field appear more shallow. Telephoto lenses are therefore useful not only for wildlife photography, but also for landscape photography. Read on to learn techniques for utilizing the unique characteristics of a telephoto lens . . . 300 mm telephoto lens - two cheetahs lying behind a log.

Understanding Depth of Field in Photography. Depth of field refers to the range of distance that appears acceptably sharp.

Understanding Depth of Field in Photography

It varies depending on camera type, aperture and focusing distance, although print size and viewing distance can also influence our perception of depth of field. This tutorial is designed to give a better intuitive and technical understanding for photography, and provides a depth of field calculator to show how it varies with your camera settings. The depth of field does not abruptly change from sharp to unsharp, but instead occurs as a gradual transition. In fact, everything immediately in front of or in back of the focusing distance begins to lose sharpness — even if this is not perceived by our eyes or by the resolution of the camera.

Since there is no critical point of transition, a more rigorous term called the "circle of confusion" is used to define how much a point needs to be blurred in order to be perceived as unsharp.