In-Camera focus bracketing - how difficult would it be?

We've had power zoom lenses from Pentax, and on certain old film cameras I believe you can set a start and stop point for auto zooming.

How difficult could it be to set a start and stop focus point, select the number of frames you want, then have the camera divide the set focus distance by the number of shots and make the exposures.

ALternatively, could this be achieved using a Pentax camera tethered to a PC and control this function with a modified Remote Assistant like piece of software?

I think that this would make an absolutely killer camera/app for macro work.

This should be possible, but maybe the way to go is to fix the lens focus and bracket by moving the sensor?

Steve

Interesting thought Steve but I'm not sure that focussing can be achieved by moving the image plane, can it?

Focus stacking is only any use if the subject doesn't move at all - so that pretty much limits it to studio work. Consequently a tethered option under PC control would be nice - but not absolutely essential as it can be done manually.

TBH, like true HDR I generally can't be bothered to invest the time required

Matt

Even a more simple type of focus bracketing would be useful to cure small focusing errors. The camera could front and back focus by set amounts. This would be easy for Pentax to add to the firmware.

I really don't know for sure, but my sense is that it should be possible for the macro application that you describe as we are only talking about a small amount of movement. I would have thought that finer control is possible by moving the sensor than the lens.

On a slighter different but related tack, am I the only one who feels that the K7's new horizon levelling feature is a clever get round for the incorrected fitted sensor problem, that several on this forum have in the the past reported. It seems to me that the feature allows more latitude in assembly and so potentially reduces costs. If this is intentional I take my hat off to the person who came up with the idea.

Steve

I have seens some absolutely brilliant stacked insect shots in the past but I must admit when I try the little buggers always move.

Super glue, or do like some catch them and put in fridge for a short while that slows them down or do as my friend did put in freezer, they dont move at all after that

It's quite easy just run the following:

; make sure live view window has input focus
WinActivate, Live View:


; Take a series of pictures and adjust the focus after each shot
Loop, %NumberOfImagesInSequence%
{
SendInput {F8}

Sleep 3000 ; give DSLR Remote Pro time to take the picture and download

if MediumFocusSteps > 0
{
; focus farther away in medium steps
SendInput ^{Right}
}
else
{
; focus farther away in small steps
SendInput {Right}
}
}

Whoops!!!! Sorry just noticed Pentax!! thought you meant
Canon Might have to get Terry to Run it

shim

I've always thought this would be easy to implement, and potentially very useful. Hence my comment the other day.

Perhaps one of the manufacturers (hopefully Pentax) will twig eventually and add it in. It could probably be done by software update - I don't think it would be a hardware thing.

Robert.

I would love this feature. It's on my wish list, almost none of which the K-7 implemented.

[OLD THREAD, NEW SOLUTION] A new solution to this problem can be found here. Awesome technology.

If only we had open source firmware, we (read Mattmatic :lol could probably impliment it ourselves.

Sorry Peter, it doesn't work like that... it's much, much more than firmware!
Light field photography works by a special lens element that produces an odd distribution of the light onto the sensor. IIRC, you ended up with 1/4 (or 1/16?) of the total resolution available for the image. So, a 16Mp sensor with the light field 'enabler' in front would give you 4Mp image - but with the ability to adjust focus in software, after the event

You don't get something for nothing, alas!

I read the papers some time back when this was first introduced. Nice to see that it's perhaps going to be something 'real' that you can buy and see.

Matt

On the focus stacking front, this has now been implemented on a number of p&s cameras. Please get it sorted Pentax! Another suggestion would be a hyperfocal mode. Would work as above with the start and end focus points selected but instead of stacking, the camera would select a suitable focus and aperture. You could let it go into stacking mode if it couldn't achieve the desired focus depth by hyperfocal alone.

Sorry Matt, by open source, I meant to facilitate a clever chap like you to implement focus stacking/bracketing in firmware. It's got to be so easy, they have it in some P&S cameras after all. I think it'd be another first for Pentax if they added this feature to their DSLR's.

I should have made it clearer.