Extension tubes with a Macro or ..................
Posted 01/11/2010 - 09:56
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The focal length of the lens doesn't change with macro tubes, just the minimum focus distance.
52mm of tubes attached to a 50mm lens will still give you a 50mm lens, but one than can focus to just beyond 1:1 magnification.
52mm of tubes attached to a 50mm lens will still give you a 50mm lens, but one than can focus to just beyond 1:1 magnification.
Joining the Q
Posted 01/11/2010 - 09:57
Link
Extension tubes do not affect the focal length of the lens.
Their job is to increase the distance between the lens & film/sensor, which reduces the lens-subject distance at focus & so increases the magnification.
Not clearly explained but perhaps enough to help!
Mike
Their job is to increase the distance between the lens & film/sensor, which reduces the lens-subject distance at focus & so increases the magnification.
Not clearly explained but perhaps enough to help!
Mike
Mike
.
Pentax:K5ii, K7, K100D, DA18-55, DA10-17, DA55-300, DA50-200, F100-300, F50, DA35 AL, 4* M50, 2* M135, Helicoid extension, Tak 300 f4 (& 6 film bodies)
3rd Party: Bigmos (Sigma 150-500mm OS HSM),2* 28mm, 100mm macro, 28-200 zoom, 35-80 zoom, 80-200 zoom, 80-210 zoom, 300mm M42, 600 mirror, 1000-4000 scope, 50mm M42, enlarger lenses, Sony & micro 4/3 cameras with various PK mounts, Zenit E...
Far to many tele-converters, adapters, project parts & extension tubes etc.
.[size=11:].Flickr• WPF• Panoramio
.
Pentax:K5ii, K7, K100D, DA18-55, DA10-17, DA55-300, DA50-200, F100-300, F50, DA35 AL, 4* M50, 2* M135, Helicoid extension, Tak 300 f4 (& 6 film bodies)
3rd Party: Bigmos (Sigma 150-500mm OS HSM),2* 28mm, 100mm macro, 28-200 zoom, 35-80 zoom, 80-200 zoom, 80-210 zoom, 300mm M42, 600 mirror, 1000-4000 scope, 50mm M42, enlarger lenses, Sony & micro 4/3 cameras with various PK mounts, Zenit E...
Far to many tele-converters, adapters, project parts & extension tubes etc.
.[size=11:].Flickr• WPF• Panoramio
Posted 01/11/2010 - 10:14
Link
I understand now, thanks guys.
Colin
“Nobody made a greater mistake than he who did nothing because he could do only a little.”
Edmund Burke (1729 – 1797)
[IMG]http://i941.photobucket.com/albums/ad254/weldingblues/K-7userbar-red.jpg[/IMG]
“Nobody made a greater mistake than he who did nothing because he could do only a little.”
Edmund Burke (1729 – 1797)
[IMG]http://i941.photobucket.com/albums/ad254/weldingblues/K-7userbar-red.jpg[/IMG]
Posted 01/11/2010 - 15:32
Link
Makes the camera-lens combination very short sighted (myopic)
Do be aware that the K7 + extension tubes with contacts + SDM lenses doesn't work that well
LiveView and menus just flash up and disappear. Very great shame!!
Matt
Do be aware that the K7 + extension tubes with contacts + SDM lenses doesn't work that well
LiveView and menus just flash up and disappear. Very great shame!!
Matt
http://www.mattmatic.co.uk
(For gallery, tips and links)
(For gallery, tips and links)
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1384 posts
18 years
Bedford
I have read lots of topics about both the merits or otherwise of extension tubes and also macro lenses.
I may have missed something (senior moment) but cannot get to grips with the focal length achieved when using tubes to give 52mm and a 50mm lens, will that equate to 102mm focal length?
Sorry this seems to be a simple question, I know somebody will explain it clearly.
Regards
“Nobody made a greater mistake than he who did nothing because he could do only a little.”
Edmund Burke (1729 – 1797)
[IMG]http://i941.photobucket.com/albums/ad254/weldingblues/K-7userbar-red.jpg[/IMG]