using extention tubes?

ok i do have a set of extention tubes but seem to have trouble not having to be right on top of the subject to get a really close up shot.... whats the best way to use them on what lens. i have the 50mm 1:1:8 II .. the kit lens 35-55mm Usually i have to use the manual focus too

the 50mm 1.8 should be good - i used that with some extension tubes on a ff camera - what camera do you have

what are the extension tubes - do they have electronic contacts - otherwise you will be at the max aperture of 1.8 and that will give a very shallow DoF
also you would need to manual focus
there is a trick to put the lens on change the aperture to the one you want hold the DOF button if you have one, then with the lens on the extension tubes connect to the camera
not tried myself - but read across a number of forums

post some images examples

the extention tubes are Kenko.. My camera is a 3Ti... i dont know if there is a DOF button or not.. will look that up..

what is a full frame camera? oh gosh i dont remember how long its been since i used them... i think this is one

Your T3i is a crop sensor versus a full frame (bigger sensor), but for simplicity sake it,doesn't make "much" difference for macro. Using the kenko tubes or any tubes essentially turns your lens into a set magnification based on the tube extension compared to the lens MM. Overall the longer the MM the further away you can be from the subject as your zoom acts as a rough focus at longer ranges. Thats the general idea without getting technical. If you wanted more working distance then you have to use less extensions basically which changes the limited "in focus" range.

if the kenco has electrical contacts - no need for the DoF trick

ok thanks..

With a 50mm FL, you need a total of 50mm of extension tubes in order to photograph lifesize (1:1)...where a 14.9mm long object would be as tall as the full height of the frame, and you will be 4*FL from the subject to the focal plane of the camera.

So, you got a good shot, but what you are seeing is a very narrow "depth of field", meaning that a very narrow plane of the image will be in "acceptable focus".

This is the "norm" for Macro photography. You have to learn to work with it!

tonylong wrote in post #14642987
So, you got a good shot, but what you are seeing is a very narrow "depth of field", meaning that a very narrow plane of the image will be in "acceptable focus".

This is the "norm" for Macro photography. You have to learn to work with it!

Or delve into focus stacking

Nature Nut wrote in post #14643061
Or delve into focus stacking

...and hope the insect complies with your command/plea, "Hold STILL!", for the focus stack to work.

Nature Nut wrote in post #14643061
Or delve into focus stacking

Wilt wrote in post #14644128
...and hope the insect complies with your command/plea, "Hold STILL!", for the focus stack to work.

Heh! I've done some nice focus stacking, for sure, if you get a reasonably still subject!