Variable aperture continous exposure

mikeodial · 10-13-2014, 05:47 AM

Originally posted by stevebrot

Yep, the OP is wanting the camera to do something like sample multiple program lines for an exposure value (EV). There was at least one film camera that could easily do this (Ricoh XRP), but it still required user intervention between exposures.

Steve

It would seem that a new feature "DOF" mode would do the trick. DF mode sounds good to me. (Pentax or any other manufacturer note, I want royalties!)

This feature would allow:

1. Set an automated set of exposures (user defined) for the DF mode.
2. Pick the range of exposures in the DOF (if autofocus lens would calculate either side of the selected focal point set by lens or user). e.g. equal points along DOF range, or in middle and at end, spread equally
3. Option to add bracketing to each exposure if needed (use existing function)
4. Ability to save as user mode.

With some intelligence this would save a lot of pictures for non-experts who get the picture in focus, but without the right depth of field, and would give an nice creative option for those that would like to see the image with different DOF without having to keep resetting the camera and therefore losing the moment of composition if the camera or subject is moving.

Unregistered User · 10-13-2014, 06:24 AM

Originally posted by mikeodial

It would seem that a new feature "DOF" mode would do the trick. DF mode sounds good to me. (Pentax or any other manufacturer note, I want royalties!)

This feature would allow:

1. Set an automated set of exposures (user defined) for the DF mode.
2. Pick the range of exposures in the DOF (if autofocus lens would calculate either side of the selected focal point set by lens or user). e.g. equal points along DOF range, or in middle and at end, spread equally
3. Option to add bracketing to each exposure if needed (use existing function)
4. Ability to save as user mode.

With some intelligence this would save a lot of pictures for non-experts who get the picture in focus, but without the right depth of field, and would give an nice creative option for those that would like to see the image with different DOF without having to keep resetting the camera and therefore losing the moment of composition if the camera or subject is moving.

I think Canon has a feature like that... Setting two focus points and the camera does the rest.

KDAFA · 10-13-2014, 07:21 AM

Originally posted by Tjompen1968

I think Canon has a feature like that... Setting two focus points and the camera does the rest.

Unless I'm mistaken, the OP is talking about having one FIXED focus point, but with several shots in a burst, each with varying DOF, but all centred on the same focal point. (And, always maintaining the exposure level.)

Whereas this Canon feature, isn't that what is referred to as focus-bracketing? As in, several shots are taken, each with progressively differing focal points, from furthest set point until nearest set point?

mikeodial · 10-13-2014, 07:31 AM

Originally posted by KDAFA

Unless I'm mistaken, the OP is talking about having one FIXED focus point, but with several shots in a burst, each with varying DOF, but all centred on the same focal point. (And, always maintaining the exposure level.)

Whereas this Canon feature, isn't that what is referred to as focus-bracketing? As in, several shots are taken, each with progressively differing focal points, from furthest set point until nearest set point?

Yes, I was talking about a fixed focal point and then variable stop exposures from there. If the camera/lens has the intelligence to do more that would be fine, but just a simple, point, focus, set the reference aperture and then shoot the pictures.

KDAFA · 10-13-2014, 07:49 AM

Originally posted by mikeodial

Yes, I was talking about a fixed focal point and then variable stop exposures from there. If the camera/lens has the intelligence to do more that would be fine, but just a simple, point, focus, set the reference aperture and then shoot the pictures.

Back on the K7 and K5 family cameras, they had something called "extended bracketing". I never did explore this capability but if I remember right, it allowed the camera to take multiple shots, but instead of varying exposure level, which is typical, the user could instead select other parameters - including white balance if I remember right. So, I wonder if one could choose to vary the f-stop...? Anyone with experience in "extended bracketing"?

Edit: This feature has been discontinued on K3.

mikeodial · 10-19-2014, 05:10 PM

Originally posted by KDAFA

Back on the K7 and K5 family cameras, they had something called "extended bracketing". I never did explore this capability but if I remember right, it allowed the camera to take multiple shots, but instead of varying exposure level, which is typical, the user could instead select other parameters - including white balance if I remember right. So, I wonder if one could choose to vary the f-stop...? Anyone with experience in "extended bracketing"?

Edit: This feature has been discontinued on K3.

That would have been great.

Mike

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10-13-2014, 05:47 AM	#16
mikeodial Veteran Member Join Date: Jan 2014 Photos: Gallery \| Albums Posts: 370 Original Poster	Originally posted by stevebrot Yep, the OP is wanting the camera to do something like sample multiple program lines for an exposure value (EV). There was at least one film camera that could easily do this (Ricoh XRP), but it still required user intervention between exposures. Steve It would seem that a new feature "DOF" mode would do the trick. DF mode sounds good to me. (Pentax or any other manufacturer note, I want royalties!) This feature would allow: 1. Set an automated set of exposures (user defined) for the DF mode. 2. Pick the range of exposures in the DOF (if autofocus lens would calculate either side of the selected focal point set by lens or user). e.g. equal points along DOF range, or in middle and at end, spread equally 3. Option to add bracketing to each exposure if needed (use existing function) 4. Ability to save as user mode. With some intelligence this would save a lot of pictures for non-experts who get the picture in focus, but without the right depth of field, and would give an nice creative option for those that would like to see the image with different DOF without having to keep resetting the camera and therefore losing the moment of composition if the camera or subject is moving.

10-13-2014, 06:24 AM	#17
Unregistered User Guest	Originally posted by mikeodial It would seem that a new feature "DOF" mode would do the trick. DF mode sounds good to me. (Pentax or any other manufacturer note, I want royalties!) This feature would allow: 1. Set an automated set of exposures (user defined) for the DF mode. 2. Pick the range of exposures in the DOF (if autofocus lens would calculate either side of the selected focal point set by lens or user). e.g. equal points along DOF range, or in middle and at end, spread equally 3. Option to add bracketing to each exposure if needed (use existing function) 4. Ability to save as user mode. With some intelligence this would save a lot of pictures for non-experts who get the picture in focus, but without the right depth of field, and would give an nice creative option for those that would like to see the image with different DOF without having to keep resetting the camera and therefore losing the moment of composition if the camera or subject is moving. I think Canon has a feature like that... Setting two focus points and the camera does the rest.

10-13-2014, 07:21 AM	#18
KDAFA Veteran Member Join Date: Dec 2012 Posts: 528	Originally posted by Tjompen1968 I think Canon has a feature like that... Setting two focus points and the camera does the rest. Unless I'm mistaken, the OP is talking about having one FIXED focus point, but with several shots in a burst, each with varying DOF, but all centred on the same focal point. (And, always maintaining the exposure level.) Whereas this Canon feature, isn't that what is referred to as focus-bracketing? As in, several shots are taken, each with progressively differing focal points, from furthest set point until nearest set point?

10-13-2014, 07:31 AM	#19
mikeodial Veteran Member Join Date: Jan 2014 Photos: Gallery \| Albums Posts: 370 Original Poster	Originally posted by KDAFA Unless I'm mistaken, the OP is talking about having one FIXED focus point, but with several shots in a burst, each with varying DOF, but all centred on the same focal point. (And, always maintaining the exposure level.) Whereas this Canon feature, isn't that what is referred to as focus-bracketing? As in, several shots are taken, each with progressively differing focal points, from furthest set point until nearest set point? Yes, I was talking about a fixed focal point and then variable stop exposures from there. If the camera/lens has the intelligence to do more that would be fine, but just a simple, point, focus, set the reference aperture and then shoot the pictures.

10-13-2014, 07:49 AM	#20
KDAFA Veteran Member Join Date: Dec 2012 Posts: 528	Originally posted by mikeodial Yes, I was talking about a fixed focal point and then variable stop exposures from there. If the camera/lens has the intelligence to do more that would be fine, but just a simple, point, focus, set the reference aperture and then shoot the pictures. Back on the K7 and K5 family cameras, they had something called "extended bracketing". I never did explore this capability but if I remember right, it allowed the camera to take multiple shots, but instead of varying exposure level, which is typical, the user could instead select other parameters - including white balance if I remember right. So, I wonder if one could choose to vary the f-stop...? Anyone with experience in "extended bracketing"? Edit: This feature has been discontinued on K3.

10-19-2014, 05:10 PM	#21
mikeodial Veteran Member Join Date: Jan 2014 Photos: Gallery \| Albums Posts: 370 Original Poster	Originally posted by KDAFA Back on the K7 and K5 family cameras, they had something called "extended bracketing". I never did explore this capability but if I remember right, it allowed the camera to take multiple shots, but instead of varying exposure level, which is typical, the user could instead select other parameters - including white balance if I remember right. So, I wonder if one could choose to vary the f-stop...? Anyone with experience in "extended bracketing"? Edit: This feature has been discontinued on K3. That would have been great. Mike