Why commlite macro extension tube does not work with d5100

That would depend on the camera, but I'm going to assume you have one with interchangeable lenses.

The camera manufacturer probably makes one or more "macro" or "close-up" lenses for your camera. Any of these lenses will let you get closer than a normal lens. Many third-party lens makers also make macro lenses.

Another alternative is to put extension tubes between the lens and the camera body. This moves the lens further from the camera, shortening the focus distance.

Probably the cheapest (and lowest quality) alternative is to put close-up lenses on the front of any lenses you already own. These screw on to the front of the lens like a filter and act like a magnifying lens, letting you get closer to the subject.

It should work with just about any lens, though it works best with moderate focal lengths (say about 24mm to 200mm). Its primary purpose is to let the lens focus much closer than normal.

When you say "no results," do you mean it's not letting you focus closer? Mount the tube on the camera, mount a lens on the tube, then focus the lens to its minimum focus distance. Looking through the viewfinder, move closer to an object until it comes into focus. Does it come into focus? How close? What lens(es) are you trying?

Extension tubes will not affect the zoom range. They simply allow the lens to focus closer by moving the glass farther away from the film or image sensor. I use them for my own close-up work.

The 18-135mm will let you focus down to 0.45m for a maximum magnification of about 1:4.8. True macro is at least 1:1 (lifesize) so this lens can't really be called a macro.

If you mean the 50mm f/2.5 lens, this will let you get to 1:1.

There should be a button or tab on the extension tube at approximately the three-o'clock position as viewed from the lens side, about where you would see the lens release button on a camera body. Press this button or tab, then turn the lens clockwise, exactly the same way you would remove the lens from the camera body.
Without knowing the make of the extension tube, I can't tell you whether it is a button or a tab, nor describe it in any further detail.

That depends on the type of camera.

Many compact cameras have a macro mode, which allows the lens to focus much closer than normal.

With an interchangeable lens camera, one usually uses a macro lens which is designed to focus closer than non-macro lenses. One can also use extension tubes or bellows to put the lens farther away from the camera (which brings the focal plane closer). Another technique that works for many lenses is to reverse it (putting the lens on backward), though this requires a reverse adapter.

To get even closer, many cameras can be mounted onto a microscope.

There isn't one. To take macro pictures you can use a macro lens, use extension tubes, use a bellows unit, or use other close-focusing gear. It's the lens that controls how close you can focus, not the camera.

If you'd like any more information, please feel free to ask.

Turn the mode dial to M for Manual. You'll lose all through-the-lens metering capability, so you'll have to review your pictures or else use another light meter.

http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&fcategoryid=216&modelid=10511
The lens does NOT have a macro feature - the closet focus is 0.35m - 1.15 ft. at the 85mm end
If you want macro a cheap way to do that is to use some extension tubes - these do NOT have glass and often come in a set of three tubes of different thickness - you can achieve better than 1:1 with these tubes

• Heres some info http://en.wikipedia.org/wiki/Extension_tube

• This is NOT a recommendation for this site - but to give you an idea what I mean http://www.srsmicrosystems.co.uk/452/Kenko-Extension-Tubes---Canon-Fit.html?referrer=froogle&utm_source=google&utm_medium=froogle&utm_campaign=pid452
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• If this solutions solves you problem, please do not forget to rate my solution.
• If not, then please comment back so I can help some more

With an SLR you only get true macro focussing on a lens that has proper macro focussing abilities. Unfortunately in the photogaraphy world, there are a huge number of lenses which claim to have macro ability but are stretching the term far too much.

Strictly speaking, macro means that the lens is capable of producing images on the sensor which are the same size as the actual subject or even bigger, at life size this is described as 1:1 macro. Your Tamron lens is only capable of a maximum 1:3.7 "macro", and that's only at the 200mm zoom setting with the subject no closer than 45cm from the lens. By SLR zoom lens standards, that's actually pretty good, but if you want to go closer and get greater magnification you need to either use a supplementary close-up filter lens or for better optical quality use a set of extension rings. The trade off with close up filter lenses is poor image quality and usually plenty of colour fringing and with extension rings is that if you're using a 2x magnification at 200mm, your f5-ish maximum aperture at 200mm becomes a very dark f10.

The only way to get good macro results is to either use a proper (=expensive) macro lens and excellent lighting, or use extension rings plus a good ring flash unit. However you can improve your macro by investing in a more capable zoom lens with a closer minimum focus distance and a better aperture at the telephoto end of the range. This can be expensive, or you can pick up some very cheap 35mm film SLR lenses. Using an adapter will never allow you to achieve infinity focus on a Canon digital SLR but you can get a close focussing 200mm f3.8 very cheaply. The crop factor of your smaller sensor means it will have the same angle of view as a 310mm lens but the aperture will remain at f3.8. As Canon digital SLR's have the deepest body register (lens to sensor distance) of the current systems then you'll also have the effect of using it on an extension ring. The downside is that you'll have to use the lens in a totally manual mode as no information will be communicated to your camera body. By mounting the lens back to front using a reversing ring you can achieve some really stunning macro magnifications but then you need a tripod, powerful flash and absolutely no wind... There was also a Makinon 80-200mm zoom which sells for next to nothing on auction websites, but it had a macro collar which allowed it to achieve around half size macro (1:2).

Alternatively, if the Fuji still works and does the job just keep it in your camera bag ready for those types of shots. overall, that seems the easiest and best solution unless you really want to get heavily into macro shooting.

I hope that I've helped you, please ask more if there's anything unclear. I've tried to keep a very complicated subject as simple as possible. Please also take a moment to rate my answer.

Macro lenses are mounted to your camera body in place of the lens you currently have mounted on the camera. If you bought the camera with the lens already mounted you may not have realized that the camera and lens are 2 separate objects. To remove your lens see page 8 in your user manual for instructions and an illustration. If you don't have your user manual handy, you can download a PDF file from NikonUSA Here.

If what you bought are macro rings, they go on the camera, then your regular lens mounts onto the ring. You can use one or more of the rings between the lens and camera to produce different macro settings.

If what you bought are macro filters, they screw on to the front of your lens. If you have a UV filter on your lens you need to remove that before you attach another filter.