I like my 50 mm lens but when I need to zoom, it is short. So I switch to my 70-300 but the f stop starts at 4.

Can I add an tele extension tube to my 50 mm? What f stop will I get? If I can achieve 100 mm at f2.8 wight this combination that would be great.

Any guys here tried it?

Originally Posted by Bukitimah

I like my 50 mm lens but when I need to zoom, it is short. So I switch to my 70-300 but the f stop starts at 4.

Can I add an tele extension tube to my 50 mm? What f stop will I get? If I can achieve 100 mm at f2.8 wight this combination that would be great.

Any guys here tried it?

Hi
I have a Vivitar 2x tel converter which I have just connected to my Nikon 50mm f1.8 to try it and the range is f3.5 to f32

Hope that gives you some idea

i know that teleconvertors like a 2xstops it down 2 stops yeah but i not sure about extension tubes having same effect! how about these macro filters on the front or a reversing ring for the lens? unless im told otherwise either of these will not change your f stops

Extension tubes cut down light, the longer the tube, the more light is lost, so in effect, you are stopping down, even if you dont move the ap ring. The only difference between a tube and a TC is that tubes have no glass, so IQ isnt affected like adding a TC

If you are on A or S priority, you'll see the camera metering to accommodate the loss of light.

You can easily test this by using a static subject, in decent light, and simply shoot ( or even just watch the metering ) without the tube, then quickly add the tube, use same settings ( stick to A priority or S priority - dont swap between them when adding the tube )

Hopefully if the light is stable and hasnt changed at all - you'll see the metering compensate and by how much.

Another thing - tubes are for getting in closer to the action, so you have to physically move youself closer to still be able to focus, unlike a zoom where your lens does the zooming for you.

Tubes are really for getting macro shots, where a normal lens is hampered by its MFD. Whack a tube on, and that MFD of say, 1 foot, becomes 2"