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brandrx

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Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.

When you point your lens in the direction of the subject you want to take then if the definition of what you are pointing at is such that it shows very little definition then the Pentax camera will attempt to go to minimum focus first then back towards infinity. If you first set your lens towards infinity then the definition of most subjects will be such that the Pentax will go directly to the subject to lock on.

Test it out yourself with your 300mm or longer lenses. Set to infinity to be ready for BIF. Then keep track if you lock on to your subject faster all the time.

Ron

--
Ron - 'We don't have time to go take pics this afternoon Carl.'
Carl - 'What do you mean? It will only take 1/1000s.'
'Keep your eyes looking forward. However, glance back now and then to see where you've come from. It will put a smile on your face.' ~ brandrx
 
Last edited:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.

When you point your lens in the direction of the subject you want to take then if the definition of what you are pointing at is such that it shows very little definition then the Pentax camera will attempt to go to minimum focus first then back towards infinity. If you first set your lens towards infinity then the definition of most subjects will be such that the Pentax will go directly to the subject to lock on.

Test it out yourself with your 300mm or longer lenses. Set to infinity to be ready for BIF. Then keep track if you lock on to your subject faster all the time.

Ron
Click to expand...
 
MightyMike said:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.

When you point your lens in the direction of the subject you want to take then if the definition of what you are pointing at is such that it shows very little definition then the Pentax camera will attempt to go to minimum focus first then back towards infinity. If you first set your lens towards infinity then the definition of most subjects will be such that the Pentax will go directly to the subject to lock on.

Test it out yourself with your 300mm or longer lenses. Set to infinity to be ready for BIF. Then keep track if you lock on to your subject faster all the time.

Ron
Click to expand...
Not all lenses seem to track back from infinity but i'm sure many do. Also from experience "chuckle" this won't work for swallows in flight LOL
Click to expand...
I havn't checked the Sigma 500mm f/4.5 but it seems to work with all of my other BIF shooting lenses. Set it to not quite infinity.

If I ever get a swallow in flight I will be so damn happy that I will most likely not even remember anything I did to get the shot. :-)

Ron
 
brandrx said:
MightyMike said:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.

When you point your lens in the direction of the subject you want to take then if the definition of what you are pointing at is such that it shows very little definition then the Pentax camera will attempt to go to minimum focus first then back towards infinity. If you first set your lens towards infinity then the definition of most subjects will be such that the Pentax will go directly to the subject to lock on.

Test it out yourself with your 300mm or longer lenses. Set to infinity to be ready for BIF. Then keep track if you lock on to your subject faster all the time.

Ron
Click to expand...
Not all lenses seem to track back from infinity but i'm sure many do. Also from experience "chuckle" this won't work for swallows in flight LOL
Click to expand...
I havn't checked the Sigma 500mm f/4.5 but it seems to work with all of my other BIF shooting lenses. Set it to not quite infinity.

If I ever get a swallow in flight I will be so damn happy that I will most likely not even remember anything I did to get the shot. :-)

Ron
Click to expand...
 
MightyMike said:
brandrx said:
MightyMike said:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.

When you point your lens in the direction of the subject you want to take then if the definition of what you are pointing at is such that it shows very little definition then the Pentax camera will attempt to go to minimum focus first then back towards infinity. If you first set your lens towards infinity then the definition of most subjects will be such that the Pentax will go directly to the subject to lock on.

Test it out yourself with your 300mm or longer lenses. Set to infinity to be ready for BIF. Then keep track if you lock on to your subject faster all the time.

Ron
Click to expand...
Not all lenses seem to track back from infinity but i'm sure many do. Also from experience "chuckle" this won't work for swallows in flight LOL
Click to expand...
I havn't checked the Sigma 500mm f/4.5 but it seems to work with all of my other BIF shooting lenses. Set it to not quite infinity.

If I ever get a swallow in flight I will be so damn happy that I will most likely not even remember anything I did to get the shot. :-)

Ron
Click to expand...
Now i have to re-check but IIRC a friend of mine who was using the HD 55-300 on his K20D was complaining about it defaulting to infinity when not sure what to lock on instead of focusing on the birdie... I thought heck that would be great as most tele subjects are out that far... but like i said i have to confirm that I'm not remembering things wrong
Click to expand...
I will also check my HD 55-300mm on the K-3/K3II tomorrow.

EDIT: I just checked my HD 55-300mm in the house and it works just like I wrote in the OP. So, set it near infinity as you wait for a BIF.

Here is an idea for you Mike: Find yourself a bad SDM DA*50-135mm f/2.8, then convert it to screw drive: http://www.dpreview.com/forums/post/57836086 , then use it on your K-1 with a Tamron 1.4X or Kenko 1.5X or Promaster 1.7X. I read over at PF that it works great that way.

Ron

--
Ron - 'We don't have time to go take pics this afternoon Carl.'
Carl - 'What do you mean? It will only take 1/1000s.'
'Keep your eyes looking forward. However, glance back now and then to see where you've come from. It will put a smile on your face.' ~ brandrx
 
Last edited:
brandrx said:
MightyMike said:
brandrx said:
MightyMike said:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.

When you point your lens in the direction of the subject you want to take then if the definition of what you are pointing at is such that it shows very little definition then the Pentax camera will attempt to go to minimum focus first then back towards infinity. If you first set your lens towards infinity then the definition of most subjects will be such that the Pentax will go directly to the subject to lock on.

Test it out yourself with your 300mm or longer lenses. Set to infinity to be ready for BIF. Then keep track if you lock on to your subject faster all the time.

Ron
Click to expand...
Not all lenses seem to track back from infinity but i'm sure many do. Also from experience "chuckle" this won't work for swallows in flight LOL
Click to expand...
I havn't checked the Sigma 500mm f/4.5 but it seems to work with all of my other BIF shooting lenses. Set it to not quite infinity.

If I ever get a swallow in flight I will be so damn happy that I will most likely not even remember anything I did to get the shot. :-)

Ron
Click to expand...
Now i have to re-check but IIRC a friend of mine who was using the HD 55-300 on his K20D was complaining about it defaulting to infinity when not sure what to lock on instead of focusing on the birdie... I thought heck that would be great as most tele subjects are out that far... but like i said i have to confirm that I'm not remembering things wrong
Click to expand...
I will also check my HD 55-300mm on the K-3/K3II tomorrow.

EDIT: I just checked my HD 55-300mm in the house and it works just like I wrote in the OP. So, set it near infinity as you wait for a BIF.

Here is an idea for you Mike: Find yourself a bad SDM DA*50-135mm f/2.8, then convert it to screw drive: http://www.dpreview.com/forums/post/57836086 , then use it on your K-1 with a Tamron 1.4X or Kenko 1.5X or Promaster 1.7X. I read over at PF that it works great that way.

Ron
Click to expand...
 
brandrx said:
If I ever get a swallow in flight I will be so damn happy that I will most likely not even remember anything I did to get the shot. :-)
Click to expand...
I managed it, once. I resorted to manual focus, because the interference from the vegetation made it impossible to do otherwise.



P.S. thanks for the advice, I'm definitely going to have to try it sometime.
 

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Mark Ransom said:
I managed it, once. I resorted to manual focus, because the interference from the vegetation made it impossible to do otherwise.
Click to expand...
Strange picture. Swallows usually are up there somewhere, not down in the vegetation. And ... is that sharp swallow really flying?
 
I find Ron's method works best for swallows as well, although it's best if you can prefocus exactly where the swallows are....!!! My technique, find a load of them together and just point and shoot....




K3 with Pentax FA*300 F4.5 taken near to their communal nesting holes.

Just to say all my comments shouldn't be taken seriously, just trying a humorous post.

--
Walt
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Recent video from pentaxforums K-1 review seems to support that as well:

Yes, they used Pentax D FA* 70-200mm lens to focus to ~10m, so not really BiF scenario, but focus speed from infinity was 2x faster than from minimum.
 
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.
Click to expand...
I agree, Ron. Resetting focus to infinity has been my standard practice for several years with telephoto lenses; DA*300, 55-300 WR, Tamron 70-200 and D FA 100mm. Not just for BIF, for any AF purpose, still or action.

Not only do I find focus locks faster when racking inward, but also the camera sometimes misses the target while racking outward with the lenses that are prone to hunting (55-300 and D FA 100mm).
 
audiobomber said:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.
Click to expand...
I agree, Ron. Resetting focus to infinity has been my standard practice for several years with telephoto lenses; DA*300, 55-300 WR, Tamron 70-200 and D FA 100mm. Not just for BIF, for any AF purpose, still or action.

Not only do I find focus locks faster when racking inward, but also the camera sometimes misses the target while racking outward with the lenses that are prone to hunting (55-300 and D FA 100mm).
Click to expand...
Hi Dan,

Not only what you wrote but another thing that I noticed when comparing my Nikon to my Pentax. When using the Pentax, if your focus ring is set in such a way, let's say from your previous last shot, and if you look through the viewfinder and everything going longer is so OOF that there is very little to no definition to anything, then the Pentax will first rack to minimum distance then focus towards infinity to find the subject. That takes a lot of time, especially for a long focus throw lens, The Nikon always just focused towards the subject. Very fast as compared to the Pentax.

Ron
 
brandrx said:
audiobomber said:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.
Click to expand...
I agree, Ron. Resetting focus to infinity has been my standard practice for several years with telephoto lenses; DA*300, 55-300 WR, Tamron 70-200 and D FA 100mm. Not just for BIF, for any AF purpose, still or action.

Not only do I find focus locks faster when racking inward, but also the camera sometimes misses the target while racking outward with the lenses that are prone to hunting (55-300 and D FA 100mm).
Click to expand...
Hi Dan,

Not only what you wrote but another thing that I noticed when comparing my Nikon to my Pentax. When using the Pentax, if your focus ring is set in such a way, let's say from your previous last shot, and if you look through the viewfinder and everything going longer is so OOF that there is very little to no definition to anything, then the Pentax will first rack to minimum distance then focus towards infinity to find the subject. That takes a lot of time, especially for a long focus throw lens, The Nikon always just focused towards the subject. Very fast as compared to the Pentax.
Click to expand...
That's very interesting. When comparing systems for focus speed and accuracy in a controlled test, you always start with the lens at a fixed position. If that position is infinity, that's the best case for Pentax and doesn't necessarily match what you'll see in the real world.

Thanks for your observations Ron, I've been shooting Pentax many years and hanging around this forum for just as long, and it's the first time I've heard this.
 
Mark Ransom said:
brandrx said:
audiobomber said:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.
Click to expand...
I agree, Ron. Resetting focus to infinity has been my standard practice for several years with telephoto lenses; DA*300, 55-300 WR, Tamron 70-200 and D FA 100mm. Not just for BIF, for any AF purpose, still or action.

Not only do I find focus locks faster when racking inward, but also the camera sometimes misses the target while racking outward with the lenses that are prone to hunting (55-300 and D FA 100mm).
Click to expand...
Hi Dan,

Not only what you wrote but another thing that I noticed when comparing my Nikon to my Pentax. When using the Pentax, if your focus ring is set in such a way, let's say from your previous last shot, and if you look through the viewfinder and everything going longer is so OOF that there is very little to no definition to anything, then the Pentax will first rack to minimum distance then focus towards infinity to find the subject. That takes a lot of time, especially for a long focus throw lens, The Nikon always just focused towards the subject. Very fast as compared to the Pentax.
Click to expand...
That's very interesting. When comparing systems for focus speed and accuracy in a controlled test, you always start with the lens at a fixed position. If that position is infinity, that's the best case for Pentax and doesn't necessarily match what you'll see in the real world.

Thanks for your observations Ron, I've been shooting Pentax many years and hanging around this forum for just as long, and it's the first time I've heard this.
Click to expand...
Mark,

Do this as just an observation:

(1) - Set your focus ring of your 300mm lens at about 8 to 10 feet. Now look through the viewfinder all around and take note of the definition of subjects from 30 feet to infinity.

(2) - Set your focus ring to infinity and look around and take note of the definitions of subjects from 30 feet to infinity.

Which of the above (1) or (2) do you think that a subject (especially a BIF) can be recognized so that you can get on it faster for that first shot?

Which of the above (1) or (2) do you think that the focus will first rack to minimum focus then back towards infinity, therefore making it even harder to spot the BIF in the viewfinder?

Which of the above (1) or (2) do you think that will focus directly to your chosen subject without first racking to minimum?

You don't really need to answer these questions to me or in this thread. It is just a way to convince yourself.

Ron

--
Ron - 'We don't have time to go take pics this afternoon Carl.'
Carl - 'What do you mean? It will only take 1/1000s.'
'Keep your eyes looking forward. However, glance back now and then to see where you've come from. It will put a smile on your face.' ~ brandrx
 
Last edited:
brandrx said:
audiobomber said:
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.
Click to expand...
I agree, Ron. Resetting focus to infinity has been my standard practice for several years with telephoto lenses; DA*300, 55-300 WR, Tamron 70-200 and D FA 100mm. Not just for BIF, for any AF purpose, still or action.

Not only do I find focus locks faster when racking inward, but also the camera sometimes misses the target while racking outward with the lenses that are prone to hunting (55-300 and D FA 100mm).
Click to expand...
Hi Dan,

Not only what you wrote but another thing that I noticed when comparing my Nikon to my Pentax. When using the Pentax, if your focus ring is set in such a way, let's say from your previous last shot, and if you look through the viewfinder and everything going longer is so OOF that there is very little to no definition to anything, then the Pentax will first rack to minimum distance then focus towards infinity to find the subject. That takes a lot of time, especially for a long focus throw lens,
Click to expand...
I agree, I've also noted this behaviour. That's why I started resetting focus to infinity in the first place. I reset now as a reflex action, I don't even have to think about it.

--
Dan
 
Last edited:
audiobomber said:
brandrx said:
Not only what you wrote but another thing that I noticed when comparing my Nikon to my Pentax. When using the Pentax, if your focus ring is set in such a way, let's say from your previous last shot, and if you look through the viewfinder and everything going longer is so OOF that there is very little to no definition to anything, then the Pentax will first rack to minimum distance then focus towards infinity to find the subject. That takes a lot of time, especially for a long focus throw lens,
Click to expand...
I agree, I've also noted this behaviour. That's why I started resetting focus to infinity in the first place. I reset now as a reflex action, I don't even have to think about it.
Click to expand...
Interesting (and useful) thread. You always hear that phase focusing is so good because it can find out how far to move from the phase difference. But, if the image is totally blurred, the phase difference cannot be found. Then, it has to have some fallback algorithm.

Just out of curiosity. What did the Nikon do?
 
brandrx said:
Hi Folks,

Always be ready for a BIF (actually most any kind of shot) by pre-setting your lens near infinity to be ready for the shot.

When you point your lens in the direction of the subject you want to take then if the definition of what you are pointing at is such that it shows very little definition then the Pentax camera will attempt to go to minimum focus first then back towards infinity. If you first set your lens towards infinity then the definition of most subjects will be such that the Pentax will go directly to the subject to lock on.

Test it out yourself with your 300mm or longer lenses. Set to infinity to be ready for BIF. Then keep track if you lock on to your subject faster all the time.

Ron
Click to expand...
 
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