beyond infinity
Aug 29, 2013 17:26:57 #
On the kit lens my D600 came with, the focus ring can go a bit beyond infinity. Does anyone know why it does that?
Thanks.
Thanks.
Aug 29, 2013 17:35:32 #
LeoB wrote:
On the kit lens my D600 came with, the focus ring can go a bit beyond infinity. Does anyone know why it does that?
Thanks.
Thanks.
Most cameras lenses do go beyond infinity these days. It is difficult and costly for manufacturers to calibrate that end, and it can change slightly with temperature and other factors. It is best to focus on a distant object in good light and move the ring counterclockwise very slightly to get the true infinity focus, and then lock it.
Aug 29, 2013 17:44:35 #
bunuweld wrote:
Most cameras lenses do go beyond infinity these days. It is difficult and costly for manufacturers to calibrate that end, and it can change slightly with temperature and other factors. It is best to focus on a distant object in good light and move the ring counterclockwise very slightly to get the true infinity focus, and then lock it.
I've always been told that you should set the ring to just short of infinity to get everything in focus.
Aug 29, 2013 17:54:50 #
lighthouse
Loc: No Fixed Abode
It's the Buzz Lightyear model.
LeoB wrote:
On the kit lens my D600 came with, the focus ring can go a bit beyond infinity. Does anyone know why it does that?
Thanks.
Thanks.
Aug 29, 2013 18:24:19 #
LeoB wrote:
On the kit lens my D600 came with, the focus ring can go a bit beyond infinity. Does anyone know why it does that? Thanks.
Leo, sometimes an object is really so far away that it's actually a little further away than infinity. That enables you to focus on it more precisely.
Hey, just kidding!!
The lens needs to be able to hunt. It will move back and forth untill it can lock focus without hitting the stops. It's said that expansion also plays a role, but thats not something I have actually research myself. SS
Aug 29, 2013 19:09:59 #
Todays AF lenses focus extremely fast and the manufactures build in a little bit of cushion at the long end so the focusing mechanism does not come up on a hard stop every time it is focusing.
Aug 29, 2013 19:37:32 #
The problem of "beyond infinity" came up the other night with my wife. She had dual knee replacements, and as she was reclined in bed, her scars were parallel, and as we know, parallel lines meet at infinity....but what about beyond infinity? Are they parallel again?
Aug 29, 2013 19:38:40 #
lighthouse
Loc: No Fixed Abode
No, parallel lines never meet.
SteveR wrote:
The problem of "beyond infinity" came up the other night with my wife. She had dual knee replacements, and as she was reclined in bed, her scars were parallel, and as we know, parallel lines meet at infinity....but what about beyond infinity? Are they parallel again?
Aug 29, 2013 19:54:28 #
Aug 29, 2013 19:55:37 #
SteveR wrote:
The problem of "beyond infinity" came up the other night with my wife. She had dual knee replacements, and as she was reclined in bed, her scars were parallel, and as we know, parallel lines meet at infinity....but what about beyond infinity? Are they parallel again?
Can you send a picture?
Aug 29, 2013 20:20:07 #
lighthouse wrote:
No, parallel lines never meet.
H.S. geometry. They meet at infinity.
Aug 30, 2013 05:51:49 #
jeryh
Loc: Oxfordshire UK
You will usually find that modern lenses, unless very expensive (ie metal) are made of engineering plastic; thus they have a built in expansion factor to allow for heat affecting the plastic- ie grow and thus affecting the focus.
Aug 30, 2013 06:02:14 #
By Euclidean geometry Parallel Lines DO NOT ever meet, by definition, that is what parallel means. Only in perspective viewing do they APPEAR to meet, like train tracks in the distance, but train tracks, when you go to the point on the horizon where they appear to meet, are still separate. It is only an illusion. Only in modern times did Einstein and others postulate that maybe they do meet, in a curved universe all returns to the starting point, like straight rays of light...also that you could draw more that one line through a point outside a line parallel to the line. Which is physically impossible...but mathematically explains relativity, which has been proven. Clear?
SteveR wrote:
H.S. geometry. They meet at infinity.
Aug 30, 2013 06:05:35 #
Aug 30, 2013 06:39:56 #
georgevedwards wrote:
By Euclidean geometry Parallel Lines DO NOT ever m... (show quote)
Ooohhh thats pretty heavy - bit like "if I wasn't me who would I be"
If you want to reply, then register here. Registration is free and your account is created instantly, so you can post right away.