Jin
Can anyone tell me some difference between the filter for camera lens? You can get one for like $7.00 to $50.00 should i spend that $50 dollars??
here are two that i'm looking at for my tamron 17-50mm f2.8
which one you guys think is better?
1. Hoya HMC Haze UV(0) - Filter - UV - 67 mm
2. B & W 67mm UV (Ultra Violet) Haze Multi Coated (2C) Glass Filter
Answer
Both these filters are well reviewed by Amazon customers. When you choose an expensive filter over a cheap one, you're looking for construction details and optical quality. A lesser filter might not hold up as well or could add some unwanted effects to your photos.
Do you use a macro lens or filter?
chaychayol
I have a macro filter on my 50mm lens, is there a such thing as just a macro lens? Where do I find one?
I bought a macro filter, at least thats what it said on the box!
Answer
What you have is a 'close up lens', also known as a diopter (because the unit used to measure its magnification is the diopter). In essence it magnifies the image 'seen' by your camera, thereby allowing you to focus on subjects that are closer to the lens. Close up lenses introduce optical abberations into the image - with many subjects, you won't notice these errors, but they are there and will be visible in precise work. Diopters are widely available in +1 and +3 strength, and occasionally you will find a +5. Edmund Scientific offers a +10 lens, but it is unmounted and you need a series adapter to use it. Practically, however, the +1 and +3 are the only diopters that make any sense. If you use a stronger lens, the subject will be so close to the front element of your lens that you will may actually find that the camera casts its shadow on the subject.
Incidentally, Nikon made some very good quality close up lenses in +1 and +3 strength. They are hard to find and more expensive, but their quality is superior.
There are also macro lenses. The ability to focus a lens on nearby subjects really is a matter of moving the lens further away from the film or sensor in the camera, and macro lenses are simply lenses that are designed to allow the lens to move further away from the camera body when it focused. Better macro lenses may also provide some additional optical corrections when focusing more closely. These tend to be fairly expensive.
There are two advantages to macro lenses. First, they are optically superior to close-up lenses. There may still be abberations, but they won't be as severe or as visible. Second, they allow you to focus on smaller subjects that is practical with diopters.
Macro lenses often have a longer focal length than normal lenses - this is an advantage because the longer focal length gives you more working distance between the camera and the subject.
Most manufacturers offer macro-zoom lenses. These are simply zoom lenses that are designed to allow close focusing. You may not get as much magnification with these as with true macro lenses, but the price is much more reasonable.
The third option is to use extension tubes. These fit between the camera body and an interchangeable lens, and tend to work better with lenses of longer than normal focal length. They tend to come in sets of three that can be mixed and matched to provide a variety of close-up options.
Two critical points:.
1. When working in the macro region, you will always get better results if you put your camera on a tripod. Depth of field is microscopic in the macro world, and to compensate for that you need to stop down the lens as much as you can - perhaps to within one stop of the maximum setting possible on the lens. That is going to require a longer exposure, and to avoid movement, you need to have the camera on a tripod.
2. Always focus manually in macro work. The autofocus system in most cameras relies on there being areas within the image with sharp contrast, and that is rarely the case in the macro world. Hence, autofocus systems tend to 'hunt' and don't work well. Turn it off, and focus manually.
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