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Something I would like to see Pentax do.

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brandrx

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Hi folks,

As you know when using AF-C that an image can be taken even if the subject is out of focus. When using AF-S the first image cannot be taken unless the subject is in focus and any image taken after that (if using continuous shooting) will be out of focus since the camera does not refocus, it just fires away at the first image focus range. So, what I would like to see from Pentax is a modified AF-S mode where after the first image is taken (when using continuous shooting) the camera refocuses for the next image. This would probably slow down your frames per second (FPS) but by golly you would never again have any out of focus BIF's.

EDIT: It would be like using catch-in-focusing only you would be in autofocus mode and the motor would turn the lens instead of your hand.

Comments?

Cheers.

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:
brandrx wrote:

Hi folks,

As you know when using AF-C that an image can be taken even if the subject is out of focus. When using AF-S the first image cannot be taken unless the subject is in focus and any image taken after that (if using continuous shooting) will be out of focus since the camera does not refocus, it just fires away at the first image focus range. So, what I would like to see from Pentax is a modified AF-S mode where after the first image is taken (when using continuous shooting) the camera refocuses for the next image. This would probably slow down your frames per second (FPS) but by golly you would never again have any out of focus BIF's.

EDIT: It would be like using catch-in-focusing only you would be in autofocus mode and the motor would turn the lens instead of your hand.

Comments?

Cheers.

Ron
Click to expand...
 
Isn't there a fire only if in focus option for AF-C (custom option 16 in my K-5IIs) focus priority in AF-C, the frame rate may slow down in order to do its best to maintain focus.
 
jm_mac said:
jm_mac wrote:
jm_mac said:
brandrx wrote:

Hi folks,

As you know when using AF-C that an image can be taken even if the subject is out of focus. When using AF-S the first image cannot be taken unless the subject is in focus and any image taken after that (if using continuous shooting) will be out of focus since the camera does not refocus, it just fires away at the first image focus range. So, what I would like to see from Pentax is a modified AF-S mode where after the first image is taken (when using continuous shooting) the camera refocuses for the next image. This would probably slow down your frames per second (FPS) but by golly you would never again have any out of focus BIF's.

EDIT: It would be like using catch-in-focusing only you would be in autofocus mode and the motor would turn the lens instead of your hand.

Comments?
Click to expand...
Isn't that AF-C, but with focus-priority selected instead of FPS-priority? Page 123 of the pdf K-5 manual I have.

I started using this mode a few months ago, and I think it does what you want.
Click to expand...
Hi jm_mac,

I also use AF-C with focus priority selected. However, as I stated in the OP. "when using AF-C an image can be taken even if the subject is out of focus." This is true even if you have focus priority selected.

Cheers.

Ron
 
Hi.

What about the AF-A? I have been using it as one of the few default settings that

I have never changed in my Kr and Kx.

(I'm not sure what settings I have selected in my K100Super at my office.)

Could somebody please tell me what disadvantages there are with AF-A, compared to AF-C?

regards

Jahn
 
MightyMike said:
MightyMike wrote:

Isn't there a fire only if in focus option for AF-C (custom option 16 in my K-5IIs) focus priority in AF-C, the frame rate may slow down in order to do its best to maintain focus.
Click to expand...
Try it yourself Mike. Set up with AF-C (focus priority set), continuous shooting. Focus on a subject, press and hold the shutter fully closed, drop the lens (as you continue to hold the shutter fully pressed) to point at your feet, or raise the lens and shoot at infintiy (mountains). The camera will contiune to fire even if it is OOF.

Cheers.

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
 
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I guess if you are panning and using a multi-point focus mode then it could think the entire scene is moving and focus on something other then the BIF. Not sure how they could firmware their way around that. Wouldn't the only way around that be to use spot focus mode and hope you can keep it on the BIF?
 
JahnG said:
JahnG wrote:

Hi.

What about the AF-A? I have been using it as one of the few default settings that

I have never changed in my Kr and Kx.

(I'm not sure what settings I have selected in my K100Super at my office.)

Could somebody please tell me what disadvantages there are with AF-A, compared to AF-C?
Click to expand...
Hi Jahn,

The way I understand AF-A is that it is AF-S as long as the subject does not move. If the subject moves then it automatically switches to AF-C. I could be worng about this though as I no longer have any cameras that have AF-A.

Cheers.

Ron
 
Bob Corson said:
Bob Corson wrote:

I guess if you are panning and using a multi-point focus mode then it could think the entire scene is moving and focus on something other then the BIF. Not sure how they could firmware their way around that. Wouldn't the only way around that be to use spot focus mode and hope you can keep it on the BIF?
Click to expand...
Hi Bob,

It doesn't matter if you have spot focus or not, as long as you are using AF-C you CAN take an image even if the subject is out of focus.

Cheers.

Ron
 
brandrx said:
brandrx wrote:
brandrx said:
Bob Corson wrote:

I guess if you are panning and using a multi-point focus mode then it could think the entire scene is moving and focus on something other then the BIF. Not sure how they could firmware their way around that. Wouldn't the only way around that be to use spot focus mode and hope you can keep it on the BIF?
Click to expand...
Hi Bob,

It doesn't matter if you have spot focus or not, as long as you are using AF-C you CAN take an image even if the subject is out of focus.

Cheers.

Ron
Click to expand...
 
Think of it like this:

If I have a lens that has an AF/MF switch on the lens, I can set it to MF. Set the camera to AF-S and continuous shooting. I am now in catch-in-focusing. Now I point at a bird in flight and press the shutter button fully and hold it pressed all the way. Nothing happens until I manually focus the lens to obtain focus. The camera will fire and continue to fire until the subject is OOF. Then while continuing to keep the shutter button fully pressed I manually refocus the lens to obtain focus again and the camera starts firing again as long as the subject is in focus.

So, do a modification to tell the camera I am in catch-in-focusing without having to set the lens AF/MF switch to MF. Now instead of my hand focusing the lens the autofocus motor does the work. The bird is tracked and images taken ONLY if they are in focus.

In my mind it should be the most simple thing to understand and to implement by Pentax.

EDIT: In a nutshell, as written by jm_mac in one of the replies above. "It wouldn't take much of a firmware change, either - it's really just a modification of AF-S - the autofocus software routine restarts after the first photo is taken and the shutter button is held down." Thanks jm_mac. That is exactly it. Breif and to the point and spot on. The autofocus routine restarts after each image is taken.

Cheers.

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:
jm_mac said:
jm_mac wrote:
jm_mac said:
brandrx wrote:
jm_mac said:
Bob Corson wrote:

I guess if you are panning and using a multi-point focus mode then it could think the entire scene is moving and focus on something other then the BIF. Not sure how they could firmware their way around that. Wouldn't the only way around that be to use spot focus mode and hope you can keep it on the BIF?
Click to expand...
Hi Bob,

It doesn't matter if you have spot focus or not, as long as you are using AF-C you CAN take an image even if the subject is out of focus.
Click to expand...
Hi Ron,

I understand what you want, now. AF-C with focus priority tries harder to nail the focus than FPS priority, but doesn't wait until focus is nailed to take the shot. A new mode would be nice, as you suggest. It wouldn't take much of a firmware change, either - it's really just a modification of AF-S - the autofocus software routine restarts after the first photo is taken and the shutter button is held down.
Click to expand...
That's it exactly. Breif and to the point and spot on of what I want.

Thanks.

Cheers.

Ron
 
So what you are saying is that when in continuous shooting mode, focus priority only works for the first shot in the sequence and it will only refocus when button is released and re-pressed. I think then that to get around that there would need to be another software controlled switch in series with the shutter button switch which could be forced open after each firing, send a refocus command and when focus is acquired again close the software switch so shutter can be released again and repeat for the continuous shooting sequence. If that is correct then afraid it would take more then just firmware unfortunately. Perhaps the shutter button switch is setting off a series of sw controlled switches in which case it would be relatively easy but somehow that hard signal to fire has to be interrupted and focus command resent.

Interesting stuff.
 
Bob Corson said:
Bob Corson wrote:

So what you are saying is that when in continuous shooting mode, focus priority only works for the first shot in the sequence and it will only refocus when button is released and re-pressed.
Click to expand...
Yes, AF-S with focus priority selected in the AF-S Custom Menu, and continuous shooting selected.
Bob Corson said:
I think then that to get around that there would need to be another software controlled switch in series with the shutter button switch which could be forced open after each firing, send a refocus command and when focus is acquired again close the software switch so shutter can be released again and repeat for the continuous shooting sequence. If that is correct then afraid it would take more then just firmware unfortunately. Perhaps the shutter button switch is setting off a series of sw controlled switches in which case it would be relatively easy but somehow that hard signal to fire has to be interrupted and focus command resent.
Click to expand...
I know that in AF-S and camera set to CIF and continuous shooting I can press and hold the shutter fully closed (or use a locking wired remote in the fully closed and locked position) all day long and the camera will only fire when I manually focus the lens to such a point to be in focus. It will continue to fire all day long (or until the battery becomes depleted) as long as I manually focus the lens to be in focus. Instead of my hand focusing the lens I want the motor to focus the lens. So, it seems to me that telling the camera that you are in CIF without being in manual focus at the lens is the way to go.

I don't really care how it is done. I only know that I would like it to be done. :-)

Cheers.

Ron
 
I don't have any DA or FA lenses with on lens manual/auto focus switch so haven't tried CIF. CIF setting over rides the shutter release button so would think it should be easy to get what you want. To be honest, I just assumed from reading the manual that based upon the.y way they defined the auto focus options that by setting focus priority in AF-C that you should get refocus after every shot even in multi-frame shooting but obviously that isn't the way it works. Perhaps if enough folks email Pentax support it will make its way into a firmwar.ed upgrade
 
Bob Corson said:
Bob Corson wrote:

I don't have any DA or FA lenses with on lens manual/auto focus switch so haven't tried CIF. CIF setting over rides the shutter release button so would think it should be easy to get what you want. To be honest, I just assumed from reading the manual that based upon the.y way they defined the auto focus options that by setting focus priority in AF-C that you should get refocus after every shot even in multi-frame shooting
Click to expand...
Yes, you do refocus after every shot when using AF-C with focus priority set and with continuous shooting set. However, even if that refocus is not quite "in focus" then the camera fires anyway. In AF-S with focus priority set and with continuous shooting set only the first image is taken in focus, the lens does not refocus after the first shot.

Cheers.

Ron
 
Let me try this for an explanation.

Read all of the below with the understanding that I am fully pressing and holding the shutter button fully.

The Pentax-FA*24mm f2 lens has an AF/MF switch on the lens. Therefore, if I put that switch to the MF position, the camera to the AF-S position, and continuous shooting on, then I am in catch-in-focusing and the camera will fire whenever I manually focus the lens until the subject is in focus. If I move the lens and manually focus on another subject (remember I have the shutter button fully pressed) then the camera will fire when the subject comes into focus. If I put the lens switch to AF, the camera to AF-S, and continuous shooting on, then the camera will focus and fire when the first image is in focus and the camera will continue to fire but any further images may or may not be in focus as the camera will continues to fire.

It just so happens that I have two Pentax-FA*24mm f2 lenses. A good one that works as it should as explained above. A second one that, even though I put the lens switch to MF, it will not allow manual focus. It still autofocuses even though the switch on the lens is set to MF. Now with that in mind follow along with that which I write below.

I put the switch on the lens to MF, the camera to AF-S, and continuous shooting on. I should be in catch-in-focusing except that I can autofocus. I autofocus by pressing and holding the shutter button fully closed and when the subject comes into focus the camera fires. I point the camera so that the subject is no longer in focus and the camera stops firing. As I contiunue holding the shutter button fully closed the camera does not fire until I point at my previously focused subject or a different subject that is of the same distance of the first subject and the camera begins to fire again. I can do this all day long. Now imagine if the camera would just autofocus the lens automatically between shots.

The thing that I want a Pentax camera to do is clear as day to me. And, it seems to me that it should be a simple thing to implement.

EDIT: Everything I've written in this thread is how things work now. What I would like is to have a menu selection option to tell the camera to restart the focusing after each image has been taken when using AF-S mode. Take an image. Electronically open the line that says the shutter is fully pressed. Electronically close that line back up. Rinse and repeat. Now, you have a camera that will track a subject and only take the image when it is in focus and it will do it continuously. Therefore, no BIF's while tracking will be out of focus.

Cheers.

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:
brandrx wrote:

Let me try this for an explanation.

Read all of the below with the understanding that I am fully pressing and holding the shutter button fully.

The Pentax-FA*24mm f2 lens has an AF/MF switch on the lens. Therefore, if I put that switch to the MF position, the camera to the AF-S position, and continuous shooting on, then I am in catch-in-focusing and the camera will fire whenever I manually focus the lens until the subject is in focus. If I move the lens and manually focus on another subject (remember I have the shutter button fully pressed) then the camera will fire when the subject comes into focus. If I put the lens switch to AF, the camera to AF-S, and continuous shooting on, then the camera will focus and fire when the first image is in focus and the camera will continue to fire but any further images may or may not be in focus as the camera will continues to fire.

It just so happens that I have two Pentax-FA*24mm f2 lenses. A good one that works as it should as explained above. A second one that, even though I put the lens switch to MF, it will not allow manual focus. It still autofocuses even though the switch on the lens is set to MF. Now with that in mind follow along with that which I write below.

I put the switch on the lens to MF, the camera to AF-S, and continuous shooting on. I should be in catch-in-focusing except that I can autofocus. I autofocus by pressing and holding the shutter button fully closed and when the subject comes into focus the camera fires. I point the camera so that the subject is no longer in focus and the camera stops firing. As I contiunue holding the shutter button fully closed the camera does not fire until I point at my previously focused subject or a different subject that is of the same distance of the first subject and the camera begins to fire again. I can do this all day long. Now imagine if the camera would just autofocus the lens automatically between shots.
Click to expand...
Interesting how that "defective lens" works.
brandrx said:
The thing that I want a Pentax camera to do is clear as day to me. And, it seems to me that it should be a simple thing to implement.

EDIT: Everything I've written in this thread is how things work now. What I would like is to have a menu selection option to tell the camera to restart the focusing after each image has been taken when using AF-S mode. Take an image. Electronically open the line that says the shutter is fully pressed. Electronically close that line back up. Rinse and repeat. Now, you have a camera that will track a subject and only take the image when it is in focus and it will do it continuously. Therefore, no BIF's while tracking will be out of focus.

Cheers.

Ron
Click to expand...
Yes it is very clear Ron and makes sense. Out of curiosity what focus area are you using? Do I recall you saying in a post a while ago that you use 5 point as that works best for BIFs?

Thanks for all your patient explanations.

Bob
 
brandrx said:
brandrx wrote:
brandrx said:
Bob Corson wrote:

I don't have any DA or FA lenses with on lens manual/auto focus switch so haven't tried CIF. CIF setting over rides the shutter release button so would think it should be easy to get what you want. To be honest, I just assumed from reading the manual that based upon the.y way they defined the auto focus options that by setting focus priority in AF-C that you should get refocus after every shot even in multi-frame shooting
Click to expand...
Yes, you do refocus after every shot when using AF-C with focus priority set and with continuous shooting set. However, even if that refocus is not quite "in focus" then the camera fires anyway. In AF-S with focus priority set and with continuous shooting set only the first image is taken in focus, the lens does not refocus after the first shot.

Cheers.

Ron
Click to expand...
 
brandrx said:
brandrx wrote:
brandrx said:
Bob Corson wrote:

So what you are saying is that when in continuous shooting mode, focus priority only works for the first shot in the sequence and it will only refocus when button is released and re-pressed.
Click to expand...
Yes, AF-S with focus priority selected in the AF-S Custom Menu, and continuous shooting selected.
Click to expand...
Can't also use the AF button set to Cancel AF to force the camera to refocus in this setup?

Thank you
Russell
 
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