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T4i : how to set the focus at infinity with manual focus ? The focus ring keeps turning

photon08
Apprentice

I have a T4i with  EFS 18-135mm.  In the manual focus mode, the focus ring seems to keep turning (many turns) seemingly without any limit.   

 

I want to set the focus at infinity (very long distance) to take astronomical objects (moon, comet, stars), but with the focus ring keep turning indefinitely and without the distance indicator in the lens (as found in some other lens), I'm quite at loss. I expected it to stop turning once it reaches 'infinity' (the farthest point) and the nearst point (in the opposite direction), but that's not the case. 

 

At least I figured out that the counterclowise rotation is going farther and farther (by manual focusing on two nearby objects at different distances).  

 

Any advice would be greatly appreciated. 

 

Thank you, 

6 REPLIES 6

ebiggs1
Legend
Legend

There is no mechanical connection with the focus ring and the lens.  It's not enough to switch to MF. and turn the focus ring. The camera has to be turned on. Be sure to tap the shutter button lightly to wake up the camera before you can manually focus. Pick any bright star and focus. Everything in the night sky will be in focus.

EB
EOS 1DX and 1D Mk IV and several lenses!

jrhoffman75
Legend
Legend

What I do for astrophotography is focus on a far object in daylight so camera can fix focus and then switch to MF and tape the lens focus ring with a piece of gaffer tape.

John Hoffman
Conway, NH

1D X Mark III, Many lenses, Pixma PRO-100, Pixma TR8620a, LR Classic

photon08
Apprentice

Thank you for the help. 

 

I was able to focus manually at a bright star/planet (Jupiter is up these days) or a far away object on the ground.

Good, now go shoot Neowise before its gone.

 

_OS11959.jpg

EB
EOS 1DX and 1D Mk IV and several lenses!

Great shot.

John Hoffman
Conway, NH

1D X Mark III, Many lenses, Pixma PRO-100, Pixma TR8620a, LR Classic

Thanx John.  I was forced to deal with traffic as you can see, bright lights coming and red light going, across the causeway bridge. I hope the OP gets reads us and gets out too.

 

It was early right after the Sun had set. EOS 1DX, 24mm, f2.8, 20 sec., ISO 1600.

EB
EOS 1DX and 1D Mk IV and several lenses!
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