catch in focus?

janstew · 03-10-2010, 12:01 AM

I just dont get it..............it says in the book........set focus on a position that the subject will pass........how do you focus on an empty spot?

If I am waiting for the horse to come past where am I supposed to focus? There is nothing but air where his head will pass?

Maybe I am missing the point?

cheers
Jan

Damn Brit · 03-10-2010, 12:10 AM

That means to focus on a point where you know the subject will be at some point (hummingbird feeder for example). The other option is to turn the focus ring and the shutter should fire when the subject is in focus.

GoremanX · 03-10-2010, 12:37 AM

Note that this only works with either manual focus lenses, or lenses that have a MF/AF switch on them. For example, it will not work with the kit lens at all. The camera must be set to AF and the lens to MF for catch-in focus to work.

Also, most lenses have a focus scale on them. You can use that to loosely guess at where you're focusing. Although I'm not sure if the focus scale of older lenses is affected by APS-C cameras.

snostorm · 03-10-2010, 12:51 AM

Originally posted by GoremanX

Note that this only works with either manual focus lenses, or lenses that have a MF/AF switch on them. For example, it will not work with the kit lens at all. The camera must be set to AF and the lens to MF for catch-in focus to work.

Hi Frank,

That's not really correct. If you short the data pin (the one farthest away from the lens lock notch) on an AF lens, focus trap will work normally. You have to short the pin, not insulate it. All AE functions will work correctly BTW.

Scott

GoremanX · 03-10-2010, 12:55 AM

Originally posted by snostorm

That's not really correct. If you short the data pin (the one farthest away from the lens lock notch) on an AF lens, focus trap will work normally. You have to short the pin, not insulate it. All AE functions will work correctly BTW.

We'll go ahead and call that the "unofficial, unwarranted" method of getting any lens to do catch-in focus (and not be able to auto-focus at all).

Nubi · 03-10-2010, 01:41 AM

Personally, I find this the best way to focus when shooting close ups. You learn to lean in and out to see if you get it spot on and when it does, it will fire.

janstew · 03-10-2010, 01:55 AM

ok so if I focus on the jump that I know the horse will go over say the top rail.......its actually not exactly where the horse will be............so it wont be in focus? Is it this hit and miss? edited to add........that i want the horse coming over the jump not just starting to jump ...........so its head will be closer than the top rail....

Last edited by janstew; 03-10-2010 at 01:57 AM. Reason: dunno if I am explaining myself!

GoremanX · 03-10-2010, 01:58 AM

Originally posted by ricstew

ok so if I focus on the jump that I know the horse will go over say the top rail.......its actually not exactly where the horse will be............so it wont be in focus? Is it this hit and miss?

If you focus on the rail, you'll take a picture of the rail (unless the focus point you're using isn't aimed at the rail). Instead, focus on the rail, and then turn the focus ring counter-clockwise a tiny bit to focus just slightly in front of the rail, and aim your focus sensor where the horse's head will be. If you're lucky, you'll get it.

Problem is, catch-in focus doesn't often react that quickly. I've missed more shots than I've caught using this technique. It's a learning experience, you won't be good at it right away.

janstew · 03-10-2010, 02:15 AM

Ahah now I get it! I better practice on the cat first........wonder if she can jump! Just as well I have time before the showjumping season starts!
Many thanks
Jan

Clicker · 03-10-2010, 08:08 AM

Catch in Focus = Automated Hyper Focus.

jmbradd · 03-10-2010, 02:56 PM

I have never been able to get this to work even with manual lenses like the takumar 135mm 2.5

(and yes i've enable it in the custom shooting menu

)

GoremanX · 03-10-2010, 02:58 PM

Originally posted by jmbradd

I have never been able to get this to work even with manual lenses like the takumar 135mm 2.5

(and yes i've enable it in the custom shooting menu

)

oops, you're right. As soon as the camera detects a manual lens (or rather when it fails to detect the lens automatically), it disables the AF mode entirely and therefore catch-in focus goes out the window.

JeffJS · 03-10-2010, 08:47 PM

Originally posted by GoremanX

oops, you're right. As soon as the camera detects a manual lens (or rather when it fails to detect the lens automatically), it disables the AF mode entirely and therefore catch-in focus goes out the window.

Completely false. The only lenses that will work in Focus trap are MF lenses or lenses that can be made MF.. BUT, Focus trap will only work in AF-S.

A50 f1.4 @1.4

M135 f3.5 @f16

Just a quick and dirty test, not accounting for flash settings etc.

GoremanX · 03-10-2010, 08:54 PM

Originally posted by JeffJS

Completely false. The only lenses that will work in Focus trap are MF lenses or lenses that can be made MF.. BUT, Focus trap will only work in AF-S.

My Super Takumar won't do it. Regardless of whether my camera is set to AF.S or MF, it still takes a picture the moment I press the shutter button. It doesn't matter if anything is in focus or not.

bullwhip · 03-10-2010, 08:57 PM

Originally posted by snostorm

Hi Frank,

That's not really correct. If you short the data pin (the one farthest away from the lens lock notch) on an AF lens, focus trap will work normally. You have to short the pin, not insulate it. All AE functions will work correctly BTW.

Scott

Do you have a closeup shot of how to short the pin? Can this hurt the camera? Can this hurt the lens? Always wanted to try catch in focus, but I only have the 2 kit lenses (18-55 and 55-300) and no extra $$ to buy another lens with.
Thanks

03-10-2010, 12:01 AM	#1
janstew Veteran Member Join Date: Dec 2009 Location: Forbes Central West NSW Posts: 311	catch in focus? I just dont get it..............it says in the book........set focus on a position that the subject will pass........how do you focus on an empty spot? If I am waiting for the horse to come past where am I supposed to focus? There is nothing but air where his head will pass? Maybe I am missing the point? cheers Jan

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03-10-2010, 12:10 AM	#2
Damn Brit Guest	That means to focus on a point where you know the subject will be at some point (hummingbird feeder for example). The other option is to turn the focus ring and the shutter should fire when the subject is in focus.

03-10-2010, 12:37 AM	#3
GoremanX Veteran Member Join Date: Dec 2009 Location: Georgia, VT Photos: Albums Posts: 1,657	Note that this only works with either manual focus lenses, or lenses that have a MF/AF switch on them. For example, it will not work with the kit lens at all. The camera must be set to AF and the lens to MF for catch-in focus to work. Also, most lenses have a focus scale on them. You can use that to loosely guess at where you're focusing. Although I'm not sure if the focus scale of older lenses is affected by APS-C cameras.

03-10-2010, 12:51 AM	#4
snostorm Veteran Member Join Date: Oct 2006 Location: Chicago suburb, IL, USA Posts: 1,535	Originally posted by GoremanX Note that this only works with either manual focus lenses, or lenses that have a MF/AF switch on them. For example, it will not work with the kit lens at all. The camera must be set to AF and the lens to MF for catch-in focus to work. Hi Frank, That's not really correct. If you short the data pin (the one farthest away from the lens lock notch) on an AF lens, focus trap will work normally. You have to short the pin, not insulate it. All AE functions will work correctly BTW. Scott

03-10-2010, 12:55 AM	#5
GoremanX Veteran Member Join Date: Dec 2009 Location: Georgia, VT Photos: Albums Posts: 1,657	Originally posted by snostorm That's not really correct. If you short the data pin (the one farthest away from the lens lock notch) on an AF lens, focus trap will work normally. You have to short the pin, not insulate it. All AE functions will work correctly BTW. We'll go ahead and call that the "unofficial, unwarranted" method of getting any lens to do catch-in focus (and not be able to auto-focus at all).

03-10-2010, 01:41 AM	#6
Nubi Guest	Personally, I find this the best way to focus when shooting close ups. You learn to lean in and out to see if you get it spot on and when it does, it will fire.

03-10-2010, 01:55 AM	#7
janstew Veteran Member Join Date: Dec 2009 Location: Forbes Central West NSW Posts: 311 Original Poster	ok so if I focus on the jump that I know the horse will go over say the top rail.......its actually not exactly where the horse will be............so it wont be in focus? Is it this hit and miss? edited to add........that i want the horse coming over the jump not just starting to jump ...........so its head will be closer than the top rail.... Last edited by janstew; 03-10-2010 at 01:57 AM. Reason: dunno if I am explaining myself!

03-10-2010, 01:58 AM	#8
GoremanX Veteran Member Join Date: Dec 2009 Location: Georgia, VT Photos: Albums Posts: 1,657	Originally posted by ricstew ok so if I focus on the jump that I know the horse will go over say the top rail.......its actually not exactly where the horse will be............so it wont be in focus? Is it this hit and miss? If you focus on the rail, you'll take a picture of the rail (unless the focus point you're using isn't aimed at the rail). Instead, focus on the rail, and then turn the focus ring counter-clockwise a tiny bit to focus just slightly in front of the rail, and aim your focus sensor where the horse's head will be. If you're lucky, you'll get it. Problem is, catch-in focus doesn't often react that quickly. I've missed more shots than I've caught using this technique. It's a learning experience, you won't be good at it right away.

03-10-2010, 02:15 AM	#9
janstew Veteran Member Join Date: Dec 2009 Location: Forbes Central West NSW Posts: 311 Original Poster	Ahah now I get it! I better practice on the cat first........wonder if she can jump! Just as well I have time before the showjumping season starts! Many thanks Jan

03-10-2010, 08:08 AM	#10
Clicker Veteran Member Join Date: May 2008 Photos: Gallery Posts: 3,241	Catch in Focus = Automated Hyper Focus.

03-10-2010, 02:56 PM	#11
jmbradd Veteran Member Join Date: Feb 2009 Location: Portland, OR Photos: Albums Posts: 325	I have never been able to get this to work even with manual lenses like the takumar 135mm 2.5 (and yes i've enable it in the custom shooting menu )

03-10-2010, 02:58 PM	#12
GoremanX Veteran Member Join Date: Dec 2009 Location: Georgia, VT Photos: Albums Posts: 1,657	Originally posted by jmbradd I have never been able to get this to work even with manual lenses like the takumar 135mm 2.5 (and yes i've enable it in the custom shooting menu ) oops, you're right. As soon as the camera detects a manual lens (or rather when it fails to detect the lens automatically), it disables the AF mode entirely and therefore catch-in focus goes out the window.

03-10-2010, 08:47 PM	#13
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	Originally posted by GoremanX oops, you're right. As soon as the camera detects a manual lens (or rather when it fails to detect the lens automatically), it disables the AF mode entirely and therefore catch-in focus goes out the window. Completely false. The only lenses that will work in Focus trap are MF lenses or lenses that can be made MF.. BUT, Focus trap will only work in AF-S. A50 f1.4 @1.4 M135 f3.5 @f16 Just a quick and dirty test, not accounting for flash settings etc.

03-10-2010, 08:54 PM	#14
GoremanX Veteran Member Join Date: Dec 2009 Location: Georgia, VT Photos: Albums Posts: 1,657	Originally posted by JeffJS Completely false. The only lenses that will work in Focus trap are MF lenses or lenses that can be made MF.. BUT, Focus trap will only work in AF-S. My Super Takumar won't do it. Regardless of whether my camera is set to AF.S or MF, it still takes a picture the moment I press the shutter button. It doesn't matter if anything is in focus or not.

03-10-2010, 08:57 PM	#15
bullwhip New Member Join Date: Jan 2010 Location: Eustis, Florida Posts: 17	Originally posted by snostorm Hi Frank, That's not really correct. If you short the data pin (the one farthest away from the lens lock notch) on an AF lens, focus trap will work normally. You have to short the pin, not insulate it. All AE functions will work correctly BTW. Scott Do you have a closeup shot of how to short the pin? Can this hurt the camera? Can this hurt the lens? Always wanted to try catch in focus, but I only have the 2 kit lenses (18-55 and 55-300) and no extra $$ to buy another lens with. Thanks