1. stevelmx5

    stevelmx5

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    I ordered the first print of the 6x12 body earlier today and should hopefully have it by Thursday. I then need to need to assemble it and cut the acrylic plates to give an integrated dark slide and shape to mount to a Graflok back and it will be (hopefully) ready to test!
     
  2. stevelmx5

    stevelmx5

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    Ah, the joys of 3D printing....

    Body.JPG

    First print was 90% successful. Looks like the model was hollowed below the top deck for some reason and the slicing software didn't add any supports to account for it so it was about 10mm off being finished! I've made some changes to my model and sent it back over to the printer to check it out so hopefully not a terminal issue!
     
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  3. Woodsy

    Woodsy POTY Winner 2009

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    I know this has probably been debated to the n^th degree on the intertubes, and not withstanding the issues it would create with focusing somewhere other than the normal ground glass, but is it possible to make a 617 back for 5x4 on the provision that the film plane is set suitably far back from the normal ground glass plane, thereby allowing the projection from the lens not to clip on the rear standard once the lens is moved back sufficiently? Obviously you'd need a lens which produces a large enough image circle as well...
     
  4. stevelmx5

    stevelmx5

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    Quick answer...yes...I've already drawn one up although I can't find the file at the moment! (and it's only been drawn theoretically on screen, I haven't tested the idea with a real lens)

    Long answer...it moves the focal plane back by around 150mm, as far as I remember, to allow for the image to project through the standard opening and still cover the 170mm wide film, which will also have an impact on the amount of light getting to the glass/film and also bellows movement.. The main issue with this is how far it moves the centre of balance back for the rear standard so increases the risk of flex etc. I never got further than a rough sketch because I wanted to focus on the 6x12 back as a priority but it's certainly something I could come back to in the future. I imagined integrating a new ground glass into the 6x17 back, along with the removable film holder. Now I've got the basic design complete for the 6x12 back, it should be a relatively simple step to adjust the design to gain 25mm on each side but I'll get this one sorted first :0)
     
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  5. Woodsy

    Woodsy POTY Winner 2009

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    Don't make me use P.Fry again... :D
     
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  6. stevelmx5

    stevelmx5

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    I’m already talking to my HR Department about unpaid leave...this Chroma stuff is going to take over!
     
  7. stevelmx5

    stevelmx5

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    Last edited: Aug 8, 2018
  8. StephenM

    StephenM

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    ?
     
  9. stevelmx5

    stevelmx5

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    “Shut up and take my money” picture above. Fry is the character from Futurama.
     
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  10. StephenM

    StephenM

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    Thanks for that. I haven't a clue what Futurama is, but I can Google that...
     
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  11. Nomad Z

    Nomad Z

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    The amount that the lens moves back to get the projected image to clear the frame depends on the focal length of the lens. A wide lens projects its image cone at a more oblique angle, so moves back less, while a long lens has it at a more acute angle and has to move back more. For example, a 90mm moves back about 26.5mm; and a 150 about 44mm.

    There is no difference to the amount of light hitting the film in the sense of losses from using extension tubes or the like because the distance from the lens to the film is the same for a given focus setting. In effect, the only thing that's moving is the frame at the back of the camera that's normally used to support the film holder. That said, there is a chance of increased fall-off / vignetting when using the 17cm width.
     
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  12. stevelmx5

    stevelmx5

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    Thanks for the clarification, particularly correcting me about light fall-off. Now you've described it, that makes perfect sense! Cheers
     
  13. stevelmx5

    stevelmx5

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    Second test print is much more successful;

    LidFitted.png

    This is the lid (left) fitted to a test print of the top 10mm of the main body (right). The alignment looks spot on and should give a good light seal so the printer is going ahead with another full print of the body.
     
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  14. stevelmx5

    stevelmx5

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    LidAndBody.png

    Top piece is the lid (upside down) showing the inset around the rim and the bottom piece is the test print of the main body showing the 2mm raised lip that runs around it and fits into the inset in the lid. The innermost holes are for securing the lid on (there will be m4 rods embedded into the body that pass through the lid and nuts on the other side), and the outermost holes are for the rods that go into the 120 spindles to wind the film on.
     
    Last edited: Aug 8, 2018
  15. stevelmx5

    stevelmx5

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    Big moment guys.....the first official unboxing video for a Chroma!



    Rich is a really nice guy who I met at the Photography Show at the NEC this year and he received his Chroma this morning. I know he'd really appreciate the views/support if you want to take a look at his first impressions of his shiny (well matte..) new Chroma.
     
  16. stevelmx5

    stevelmx5

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    I’ll just leave this here...

    IMG_1319.JPG

    IMG_1320.JPG
     
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  17. Andysnap

    Andysnap POTY (Film) 2015

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    stevelmx5 likes this.
  18. niko

    niko

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    owe you so and so, behave you!
    its not getting easier to avoid starting using larger formats- I have enough "geek hobbies" as it is
     
  19. stevelmx5

    stevelmx5

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    Sorry bud but yes, it’s a 6x12 body that’s going to be fixed to a 4x5 Graflok plate for use on any large format body . The same body will also be used as the basis of my handheld 6x12 mirrored camera down the line.
     
  20. stevelmx5

    stevelmx5

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