Nidelva river through Trondheim Norway

Nidelva river through Trondheim Norway
by Saaru Lindestokke                

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2

Michael Clark's answer should suffice for nearly all commercial camera lenses. The long answer is that the effect of blocking part of an aperture depends on where that aperture is in the lens system. Since the rear element is typically close to the image plane, the blockage occurs primarily in "image space," darkening the geometric area as shown in the ...


0

When stopped down, does light still pass through all of a glass element behind the aperture blades? No (Assuming the rear element is large enough to pass through all of the light allowed through by the aperture when it is wide open). Does this mean that light only passes through the middle of each lens element behind the aperture blades? Yes. ...


7

It varies based on several factors: Focal length: Same sized obstructions on the rear elements of telephoto lenses show up more than on the rear elements of wide angle lenses. Aperture: Same sized obstructions in the center of the rear element will show up more at smaller apertures than at larger ones. Roger Cicala, the founder and chief lens guru at ...


2

The school photo finishing industry uses cluster lenses to project multiple identical images on photo paper. Try as you might to make all the lenses on a board identical, some pass more light than their neighbors. We resorted to dotting the lenses with opaque spots of paint to equitize. These act to reduce the amount of light that transverse the lens. As ...


1

The answer to the first part of your question is yes. The answer to the second part of your question is dimmer, increased flare, and poor focus if you use white material and with slightly less flare with darker material. The size of the hole will determine the amount of light fall-off and the annular size will determine the amount of focus degradation due ...


2

Every type of contamination on a camera lens is out of focus so the answer is that it would most definitely not cause 'graininess'. You may, however, notice a reduction in brightness or contrast of the image as less light will be going through the lens. All camera sensors produce visible 'noise', which used to be called grain in the days of film and which ...


6

Dirt can never cause grain. It's more likely you are seeing digital noise. Switching to lower ISO should help.


6

Yes, it's possible — but it's more likely that that's just how it is. You can't expect miracles from a point and shoot camera, and fine detail with no noise when "pixel peeping" would be a miracle. You say that the results are satisfactory for viewing as a whole on a computer screen. They'll also be fine when printed at reasonable sizes. In any case, it's ...


3

Yes, the 18-55mm lens will of course also do 35mm. This focal length determines the angular field of view of the lens. So the 18-55 is more versatile in that way. Because 18mm is a 2x wider view (than 35mm), which is called wide angle, and 55mm approaches a magnified or zoomed in view, of about a half again larger subject (in a smaller zoomed view than the ...


1

If I understand your example correctly, the focal plane changes with color. I think what you show here is axial (longitudinal) chromatic aberration. APO lenses are not necessarily a solution here. Canon does not mark any lenses as such and as far as I know none of their macro lenses are perfectly corrected for axial CA. The lens you have is pretty good. ...


1

Most objectives (I have yet to see a counter-example) do not have hard fall-off at the edges because optics make it very rare case - to draw a sharp edge on the sensor an objective should have some inner part of it to be in a specific place. Every objective which you will try will draw a smooth circle on the sensor and you will only have a chance of dark ...


3

The camera lens is a converging lens. Light rays from the subject enters the lens and the lens, due to the shape and density of the glass lens, emerge tracing out a revised path. This path resembles a cone of light. We focus the camera by moving the lens forward or backward. This action adjusts the position of the apex of the cone. We want the apex to just ...


11

You are seeing chromatic aberration — a prismatic effect which, as you nicely illustrate, reduces sharpness even in black and white photography. A lens which has greater correction for this is called an apochromatic lens — often something like "APO" in the lens name. Note that in lenses for telescopes and microscopes, you'll often also see achromatic ...


5

The only guarantee is that a DX lens will throw an image circle approximately large enough to cover a DX sensor. Some throw them a bit larger, but the only way you'll know if a given lens does that or not will be to try it. Carrying your math a bit further, the DX diagonal is 0.12mm smaller than that of the AX100. The pixels on that sensor have a diagonal ...


0

I would go for the slimmer cause I like to mount more than one filter. I often work with ND Filter and Cir Pol Filter combined, for example in a creek in the woods or at sea shores. I would recommend to buy the Hoya HD Cir Pol instead of the Pro1. It has a higher light transmission, thus it is easier too use in lower light conditions, with viewfinder and ...


3

Can any of you tell me which would one be preferable for landscape photography? The slim one is slimmer, which means that there's less chance of the edge of the filter being visible in images taken on a wide angle lens. An 11-16mm lens is certainly wide enough to justify a slim filter on a full frame camera, but since your 550D has an APS-C sized ...


-4

The word lens is from the Latin, shaped like a lentil seed. This is a disk that bulges out of both sides, we call this lens shape, convex – convex. A single transparent convex – convex lens will do the deed. We task the camera lens to gather image forming light rays from a 3 dimensional world (object at different distances) and project their image on a flat ...


3

Take a look at these two Schneider lenses that both have 90mm focal length: The first has coverage for "35mm" format, the second coverage for large format. I am not sure, but I think the main reason for the difference in size is the fact that the large format lens is a "simpler" design, i.e. fewer elements/groups. The reason a large format lens can use a ...


2

A few points to consider (mostly adding to mattdm's answer): A manually focusing 135mm Nikkor 2.8 lens in F mount is about 91.5mm long, and looking at a drawing of the lens most of the optical elements are in the front. So a comparison with a zoom lens isn't really fair -- it is a much more complicated lens. Strictly speaking, a telephoto lens is one ...


19

The focal length is the distance from the (theoretical) center of the lens to the image plane. On the large format camera, there's a lot more camera between the lens and the film. The lenses are also often relatively simple — there's no need for a focusing mechanism in the lens itself, for example. @osullic gives the example of the Schneider PC TS ...


0

I recently purchased a D3300 in a package with both kit lens (18-55mm and 55-200mm). After a couple months I also purchased the 35mm f/1.8 and am thrilled with the results. This is my first DSLR and the combination of the three lens has given me plenty of room to learn and develop. Some pictures look better with the 35mm lens and then cropping the image ...


10

I have found these lens Nikon AF 70-300mm f/4-5.6G in a very good price. I am planning to use them mainly to take pictures of the moon. I am aware that this lens does not have image stabilisation. Is this a major drawback ? If you plan on shooting a full moon on a clear night, handheld, it shouldn't be, because you can easily get shutter speeds faster ...


1

No, since you will want to have the camera and lens mounted on a stable tripod and use a remote or timer release to trigger the shutter. If your shutter speeds fall below about 1/125 second you would also benefit from using mirror lockup.


5

If you use a tripod, image stabilisation is not necessary. If shooting hand-held, image stabilisation can become important. Given the rule of thumb that 1/focal length is the longest hand-holdable shutter speed, that you likely want to use 300mm and that you likely take the image at night, chances are you have to pick a higher ISO value to keep the shutter ...


0

I took mine to the beach for several days, and took very good care of it, however after a few days, it locked up and wouldn't extend. I asked several camera experts w/ no avail. I finally used a little "elbow grease" and took the risk and it freed right up!! Very finikcy....keep it clean!!


1

You will want to have a non-extending zoom lens when using anamorphic adapters which often need to be tied with a lens support (like Lanparte lens support); not only to support them but to avoid them from turning when using focus, which would skew the image on an anamorphic.


0

I've been using this lens for a few years now and I definitely have not had any problems with it. I like what I get from it.


0

In other words, a 50mm f/1.8 lens on an APS-C camera would act more like a 80mm f/2.8 (approx. 1.8 * 1.6x) lens in 35mm equivalent — for depth of field, not considering exposure. Yes, a 50mm f/1.8 lens on an APS-C camera would act more like a 80mm f/2.8 (approx. 1.8 * 1.6x for Cannon) lens in 35mm equivalent, as far as DOF and to some extent image noise ...


1

This question (or a variation on it) pops up periodically, and one thing that I think hasn't received much attention is how much more there is to this than "adding an autofocus motor" eludes to. (And, I enjoy exploring into the realm of the somewhat ridiculous.) Honestly, adding an "autofocus" motor is not going to be hard. Grab a small and speed-reduced ...


2

DO NOT ATTEMPT THIS WITHOUT A SOLAR FILTER which is metal that absorbs harmful levels of electromagnetic radiation that will damage your EYES and maybe your equipment (which can be replaced, unlike your eyes). ND Filters use dyes which do NOT cut the radiation in the dangerous areas of the spectrum. Further, the size of Mercury will be minuscule.


6

How can I modify my NIkon D5500 so I can make a vintage lens auto focus? You can't. I learned that using a TC-16A AF Teleconverter 1.6X might help ... Whatever you learned is probably wrong. From my googling it looks as if the TC-16A was designed to turn AIS lenses into AF lenses (i.e., an interim step to add electronic communication and the ...


8

Field of View The sun is approximately 0.5° across in the sky. At 200mm on a DX (1.5 crop factor) body, the field of view (FoV) is 6.9° (wide) / 4.5° (high) / 8° (diag). In terms of Sun diameters (☉), the 200mm FoV is 13.4 ☉ wide by 9 ☉ high. According to Wikipedia, Mercury's diameter when viewed from the earth during May transits is 12 arcseconds. In ...


5

Probably not. But it depends on just how dark and what type your ND filter is. It can be very dangerous to both your equipment and your eyes to try and take photos of the sun without the proper precautions! The most damaging portion of direct sunlight to the internals of your lens, camera, and eyes are in infrared, not in the visible spectrum. The UV filter ...


0

Exposure, well, if you're using green-box Auto, that's a risk you take, but if you're spot metering, as well as spot AF, chances could be you didn't aim where you thought you aimed. The lack of IS could be another issue, if you were used to having it on the 18-135. Increasing your shutter speed to at least 1/focal_length is a given, and you may want to ...


1

People like me who still shoot old, manual, film cameras loaded with B&W film. Primes are cheaper, have basically nothing that will fail, and you can get faster primes for the same price. I also don't need AF (my bodies are all older Nikons that are MF only), and most MF lenses are primes. Having access to a bigger aperture when using film can be a big ...


0

I have a D5300 and I recently bought a 20mm f/1.8 (http://www.nikon.com.au/en_AU/product/nikkor-lenses/fx-format/single-focal-length/wide-angle/af-s-nikkor-20mm-f-1-8g-ed) and it's honestly been my best purchase thus far. I forked out for it because I plan to upgrade to a FX body sometime in the near future, but if you want a really good reliable wide lens, ...


2

If you buy a $1,200 lens expecting it to instantly improve your photographs by a factor of six over your $200 kit lens you're going to be severely disappointed every time. It is the photographer that takes pictures, not lenses. A better lens will only allow a photographer to take a better picture if the photographer's experience and skill level can take ...


2

Might also have to do with speed. Some zooms are limited in their range, being slower at longer focal lengths. Take a look at photographers on sidelines of football matches; they might have one long fast zoom and then a shorter lens on a second body in case the player gets close. They are, however, specialized lenses. Usually for situations where you are ...


1

I can guess at two things that might be causing you to see less IQ with the new lens. 1) The widest aperture on your kit lens was 3.5, and you are not quite used to shooting at 2.8. The wider 2.8 aperture will definitely give you a "softer" look with the narrower depth of field. 2) The kit lens had IS and the new 24-70 MkII does not. Without seeing some ...


45

Who in the world buys large primes? Wildlife and sports photographers, mostly. I'm struggling to see how one would find use in a long focal length prime, 300mm and above for example: without zoom, isn't your shot composition always at the mercy of how close or far away your subject is, meaning heavy cropping is almost always necessary in post? ...


4

You might buy one in order to get a balance of high quality, reasonable size and weight, fast aperture, and a lower price. As you say, people often get shorter primes because they like a particular field of view, and I don't think that's usually the case beyond, say, 90mm (in 35mm terms). That list of compromises can't be avoided — but giving up zoom lets ...


0

All Nikon cameras since the old times use the same F mount. So any f-mount lens will work on your camera. However, only those with an integrated AF motor will be able to autofocus on a d5x00, and many old lenses won't be able to "tell" their aperture to the camera. So you'll have to use them in manual exposure, manual focus mode. For night time ...


0

I am not a Nikon user but if you are open to third party lenses I can recommend Tokina 11-20 f/2.8. I have a 11-16 f/2.8 (the predecessor of 11-20) and use it on my Canon (Tokina makes it for both Nikon and Canon). Gives me fantastic results and quite nicely built. Sample images: ...


1

We use a blimp on movie sets for sound deadening loud cameras like Nikon. Maybe you could put your gear into a padded fibreglass shell for shock protection. This guy made his out of a Pelikan™ case. http://blog.blairbunting.com/guest-post-diy-sound-blimp-project/ Fatboy also has a solution cheaper than replacing your gear. ...


0

I have found Edmund Optics/Scientific to be a good source of different types, quality, and grades of optical supplies for prototyping. I have also used LEGO™ blocks for building various types of cheap lens mounts and component assemblies. The parts are standard, and can be modified for any kind of custom piece. Sugru™ is another wonderful material for ...


0

Depending on the quality of the image you expect, a supplementary lens might satisfy your requirements. At the magnifications you mention, positive meniscus lenses can magnify your image. Along with the magnification, however, will come severe color abberations and image distortion that can make the results unuseable.That said, visit your local optometrist ...


2

With the 70-300mm, I guess I could take pictures of the moon or any other close up objects 300mm doesn't really get you close enough for the moon. You could use a teleconverter, but you'd either have to get a third party one or make warranty-breaking modifications to a Nikon one. However, you can get some nice wildlife pictures at 300mm, particularly ...


4

The Minolta Hi Matic 9 has a fixed 45mm lens. It is not possible to switch lenses. Source: oldcamerareview Lens variety and interchangeability – Nope, you won’t get that either. But, if you are the person that had to save up and finally got your Leica and lens, you probably can’t afford another lens for awhile anyway.


1

If I understand correctly (looking at the manual, pictures of the camera and repair advice for this camera), the shutter for this camera is in the lens and the lens isn't designed to be removed. Also, this is a rangefinder camera (so the user isn't looking through the lens to frame the picture). Zoom lenses for 35mm normally are designed for SLRs -- where ...


1

Don't buy a film SLR camera just because it is cheap. Almost any film SLR is going to be dirt cheap these days simply because no one wants them. Once you buy the film and pay for processing and printing you will quickly discover that you no longer have a "cheap" camera. Even if you are prepared to pay for the film costs, the $25 Vivitat 3000S would not ...



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