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Thread: New Autofocus 4x5"

  1. #11

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    Re: New Autofocus 4x5"

    Niche market camera. IMO, autofocus is not that useful for sheet film cameras given the advantages sheet film view cameras can offer camera movement with highly controlled areas of focus and to what degree of apparent focus. What area of the view finder is used as the autofocus zone? If typical of autofocus cameras in the past, it would mean get the camera to focus at in that area of the view finder than re-compose the image as needed which alters the area of accurate lens focus. Not that appealing given how highly developed modern digital autofocus cameras are today. Then we come to lens choices which is IMO a very serious limitations.

    This is effectively an autofocus 4x5 "point & shoot with significant cost per sheet of film and limited to the number of film holders to be used. Granted a grafmatic film holder could allow six sheets per holder. Question remains does the idea of an autofocus 4x5 "point and shoot" fit a market need?



    Bernice

  2. #12
    (Shrek)
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    Re: New Autofocus 4x5"

    Interesting project, the technical challenges are surmountable with today's electronics, I would love to see it in action. Of course it sounds completely unsuited to my style of shooting, but someone out there wants this.

  3. #13
    Tin Can's Avatar
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    Re: New Autofocus 4x5"

    Autofocus needs the improved eye focus with follow of NIKON Z

    Eyes are it and 4X5 is too small

    5X7 or 8X10 at least so we can contact print

  4. #14

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    Re: New Autofocus 4x5"

    Quote Originally Posted by Neal Chaves View Post
    I have had a lot of experience photographing people in all situations with hand-held press and view cameras and I have also used FujiFilm digital cameras since the early 2000s. Graflex actually advertised the Kalart rangefinder as "automatic focusing" in the 1940s and 50s. With today's digital cameras, auto focusing means much more than rangefinding. We have face detection, eye detection, smile detection, identification and numerous other features, some these I have found very useful and advantageous. There are many reasons I might choose to use a hand-held press camera rather than a digital camera, but I don't feel that automatic rangefinding would be much of a benefit over a cam-coupled, split image rangefinder with rangelight or even be much faster.
    By autofocus, it means that you don't have to focus. That it moves the lens for you, based on where you want to focus. This is the definition of autofocus.

    This is faster and more accurate, but one of the main benefits is actually that you can calibrate multiple lenses in this. This has always been an issue with speed graphics, where you can only calibrate one lens.

    The other big benefit are the framelines, you get accurate projected framelines for all formats & lenses.

    So its exactly developed to solve all the problems that are in current solutions. I have owned them all.

    This is designed to suit my own need, to solve all the issues i have had with cameras. I have shot mainly handheld 4x5" from the start, and always trying to find the best way to do it. So this is camera designed by a photographer, to solve issues.

    Its also designed to be as compact as possible, its actually more compact than most manual focus "point & shoot" 4x5" cameras.

    That said, i do also have another system that i'm going to release that might be more suited for you.

  5. #15

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    Re: New Autofocus 4x5"

    Quote Originally Posted by Tin Can View Post
    Autofocus needs the improved eye focus with follow of NIKON Z

    Eyes are it and 4X5 is too small

    5X7 or 8X10 at least so we can contact print
    5x7 and 8x10" are not really something you can shoot handheld practically. The bellows draw would be too much for anything other than wide angle use. 4x5" is still perfectly practical as a handheld camera. This is made to be a realistic tool.

    Also you need to understand the difference of a digital camera, that has a sensor instead of a film. I cant read the film to decide where there might be eyes

  6. #16

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    Re: New Autofocus 4x5"

    Quote Originally Posted by Bernice Loui View Post
    Niche market camera. IMO, autofocus is not that useful for sheet film cameras given the advantages sheet film view cameras can offer camera movement with highly controlled areas of focus and to what degree of apparent focus. What area of the view finder is used as the autofocus zone? If typical of autofocus cameras in the past, it would mean get the camera to focus at in that area of the view finder than re-compose the image as needed which alters the area of accurate lens focus. Not that appealing given how highly developed modern digital autofocus cameras are today. Then we come to lens choices which is IMO a very serious limitations.

    This is effectively an autofocus 4x5 "point & shoot with significant cost per sheet of film and limited to the number of film holders to be used. Granted a grafmatic film holder could allow six sheets per holder. Question remains does the idea of an autofocus 4x5 "point and shoot" fit a market need?



    Bernice
    Yes, you are right. This is a niche market camera. Its made to solve my own problems, i developed it as a tool for my own work.

    Its not made to replace view cameras, its made to replace press cameras. Even though i shoot 4x5" handheld, i shoot 8x10" with view & field cameras. And sometimes even 4x5".

    " it would mean get the camera to focus at in that area of the view finder than re-compose the image as needed which alters the area of accurate lens focus. "

    This is a good point, in close focus this needs to be calculated in. The camera has an accelerometer & gyro, so it knows its orientation in space and can use trigonometry to adjust the focus when you recompose you shot.

    Kinematic holders hold 10 sheets, so its comparable to medium format in that sense. Grammatics hold 6. And its exactly build for these holders. The cost is also low, thanks to Fomapan 200 .

    Im not sure how lens choices are a limitation? Plenty of lenses. Thats exactly one of its appeal, as there are a lot of really interesting LF glass out there from the press era. And the modern stuff.

    I dont really even care about the market need to be frank Its made for my own work, and i also will make it available for others. I did not make this to please the markets.

  7. #17

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    Re: New Autofocus 4x5"

    Quote Originally Posted by John Layton View Post
    Focus accuracy of 1-2mm would be fantastic if existing LF film holder/transport systems could reliably support this. Hmmm...possibly develop some kind of real-time (IR?) film position sensor which would instantaneously adjust the focus mechanism to accommodate environmentally caused deviations (expansion/contraction/swelling/sagging/"popping" of film) of actual film plane - at least at the exact position of actual focus measurement (as films can swell/contract/sag unevenly) to ensure that at least this area would be truly in focus every time...even at max. (wide open) apertures? Perhaps via a selected (or selectable) area focus lock mechanism - like...place the circle on the face, eyes, or wherever, hold down the shutter button halfway, re-compose (if necessary) and then trip the shutter completely - and the focus compensation mechanism would continually adjust for said (film position) deviations until that very instant?
    Sounds complicated But that would actually be quite easy, i just dont think its actually necessary. The firlm sensor.

    The other stuff is pretty much impossible in a film camera. It would require a 4x5" sized digital sensor. Seems people dont really get the difference of having a sensor as capture device compared to film. All these face detection etc, require you to have a sensor you can read and detect the faces in.

  8. #18

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    Re: New Autofocus 4x5"

    Quote Originally Posted by Bob Salomon View Post
    Back in the 90s a rich guy in Germany patented a modular AF view camera system that took backs from 23 to 11x14. Electronics were mostly within the rail system. They exhibited at Photokina one year but never produced anything other then a prototype and a couple of beautiful brochures. But the backer also owned a salmon farm in Sweden or Norway and featured all you could eat smoked salmon, if they knew you at their booth.
    A friend of mine who had been export manager of both Rollei and later LInhof was hired to be export manager for this new camera system.
    I hope this new design has a better future then this older camera had.
    That sounds interesting. Always been motivated by the likes of Peter Gowland etc photographers who build cameras for their own needs and disregarded the norms.

  9. #19

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    Re: New Autofocus 4x5"

    Quote Originally Posted by Guadarmar View Post
    How can you use a little tilt/swing with a viewfinder and handheld?

    No shifts, no tilts, no real reason for LF.
    If you want to go fast and light, so go small.

    If a AF should follow moving objets low moving mass is required.
    LF lenses in a shutter are not on the light side.

    What will be the use of AF in LF?
    It has not tilt & swing. Though i have though about maybe adding it, but it might be something in the future and this will stay as base model. As im far more interested in making it really solid in its base functions.

    Though there are some features i'm planning in developing for this, that i will make public later.

    I have tested this upto 1.75kg. I actually way over specced it. Its not particularly good at following moving objects, that is something that still needs developing. It will have some sort of follow focus mode, but the type of laser used does not like fast moving objects. But this is about the laser system, not about the lens weight.

    The main purpose is simply to focus accurately, to be able to calibrate multiple lenses, and to have accurate framelines for all formats & lenses. As these are features that lack from all the old press cameras.
    They had mostly separate viewfinders & rangefinders (expect Beseler C-6 i think, and the Vuefocus system of Burkes & James). Had possibility to calibrate only one lens, or used fixed cams for specific lenses.

    "What will be the use of AF in LF?" To waste large quantities of film in an instant! What is the function of AF in any format; to speed up things.

    But the truth is, this is not so much about AF, its more about the accuracy that this type of focusing method offers. And the above mentioned features.

  10. #20

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    Re: New Autofocus 4x5"

    Quote Originally Posted by Tin Can View Post
    I posted years ago my Laser FocuSpot

    Works great but not for people or critters

    Trees and bridges survive the cosmic blast
    Yes, Iw done that also. This is basically a descendent of the Kalarts lightbulb system. As i used a similar laser system on my previous cameras long a go. Had one in a modified Patent Etui 9x12, that i shot a lot of film though. I also used the idea from Olympus XA4, that had a wrist strap that also doubled as a close focus distance measuring device I had that in my Patent Etui 9x12 to focus as close as 30cm.

    And this is simply an evolution to my previous work. It was finally possible for me to build this, thanks to 3D printing and the availability of microcontrollers.

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