Page 2 of 2 FirstFirst 12
Results 11 to 18 of 18

Thread: 4x5 Camera

  1. #11

    Re: 4x5 Camera

    Quote Originally Posted by Dan Fromm View Post
    Steve, acrylic is hygroscopic, will take up water from the air. Probably not a problem with y'r camera because the relative humidity is the same on all sides of y'r bits of plastic, but the reason that acrylic sheet makes a very bad aquarium cover. The water side takes up more water than the air side and the sheet warps badly.

    But acrylic is less impact resistant than polycarbonate. Have you considered using polycarbonate instead of acrylic? I mean, both are equally machinable ...
    Thanks for the advice but the only information I’ve found regarding water absorption is on aquatic forums where acrylic has been used fully submerged in tank sumps 24x7. The manufacturer stats suggests very minimal absorption over the life of the material. Also, the Chroma is made using multiple layers bolted together rather than single large panels so again, I think it’s highly unlikely that any warping will occur. As above, I have an acrylic unit in my garden all year round that has very long flat panels and have seen no ill effects.

    With regards to polycarbonate, I’ve never seen it in sheet form in anything other than transparent finish (as it generally replaces glass). As a result, it’s not suitable for a camera, hence the use of laminated coloured acrylic.

  2. #12

    Join Date
    Sep 1998
    Posts
    10,522

    Re: 4x5 Camera

    Quote Originally Posted by stevelmx5 View Post
    Thanks for the advice but the only information Iíve found regarding water absorption is on aquatic forums where acrylic has been used fully submerged in tank sumps 24x7. The manufacturer stats suggests very minimal absorption over the life of the material. Also, the Chroma is made using multiple layers bolted together rather than single large panels so again, I think itís highly unlikely that any warping will occur. As above, I have an acrylic unit in my garden all year round that has very long flat panels and have seen no ill effects.

    With regards to polycarbonate, Iíve never seen it in sheet form in anything other than transparent finish (as it generally replaces glass). As a result, itís not suitable for a camera, hence the use of laminated coloured acrylic.
    Go to the Rimowa factory web site in Germany and look at their range of polycarbonate luggage. Polycarbonate is available in a wide range of colors and textures. Rimowa invented polycarbonate luggage and none of them are clear or translucent.

  3. #13

    Re: 4x5 Camera

    Quote Originally Posted by Bob Salomon View Post
    Go to the Rimowa factory web site in Germany and look at their range of polycarbonate luggage. Polycarbonate is available in a wide range of colors and textures. Rimowa invented polycarbonate luggage and none of them are clear or translucent.
    Thanks. As I said though, the availability of polycarbonate in 2/3/5mm thick sheets and multiple colours is limited. Whilst there are finished products like the suitcases you mentioned, the most common sheets are translucent and considerably more expensive than acrylic (up to 10x).

  4. #14

    Join Date
    Sep 2014
    Location
    North Dakota
    Posts
    555

    Re: 4x5 Camera

    Acrylic?
    Will it generate static electricity when in use?
    How can it hold in sub zero temperatures? Especially if it gets bumped?
    I tend to procrastinate on stuff. One of these days I'll do something about it.

  5. #15

    Re: 4x5 Camera

    Quote Originally Posted by Willie View Post
    Acrylic?
    Will it generate static electricity when in use?
    How can it hold in sub zero temperatures? Especially if it gets bumped?
    I havenít seen any signs of static build up in my own use and am not really sure in what conditions it would be?

    With regards to sub zero temperatures, acrylic is rated for use down to -20 (and-40 with some manufacturer stats) so I donít foresee any issues.

  6. #16

    Join Date
    Sep 1998
    Posts
    10,522

    Re: 4x5 Camera

    Quote Originally Posted by stevelmx5 View Post
    Thanks. As I said though, the availability of polycarbonate in 2/3/5mm thick sheets and multiple colours is limited. Whilst there are finished products like the suitcases you mentioned, the most common sheets are translucent and considerably more expensive than acrylic (up to 10x).
    Sorry, I did see where you specified thickness, but having visited the Rimowa factory in KŲln several times and watched the molding and assembly, from flat sheets of polycarbonate I know that they are using polycarbonate in colors in some of those thicknesses. Of course, with the volume that they have, it is very possible that the pc manufacture produces colors to their specification.

  7. #17

    Join Date
    May 2015
    Location
    SooooCal/LA USA
    Posts
    1,169

    Re: 4x5 Camera

    Great for trying, but acrylic is heavy for it's strength, not stiff along it's flat surface, can get brittle, can craze from environmental exposure or strain, not internally interlocked, scratches/scuffs without much effort, needs to be cross-supported as thin stuff will bend/flex along it's surface plane, different internal tensions due to harder outer surfaces to slightly softer core, all parts generally have to be hand worked (edges typically burn a little using laser cutter + flat stock), and not really strong cast...

    Now, most makers are forming parts with ABS CNC forming/machining methods, but the internal stiffness and brittle problem still exists for slender pieces (but parts are typically re-inforced with some ribbing)...

    I'm not trying to discourage your efforts, but we have been seeing other attempts using high tech to make new LF cameras (and some failures with cracking and other issues), and in this crowd, many are still using over 100 year old examples of gear that is still going strong... And some good new applications of modern materials such as Walker's Titan, so we are not just poo-pooing any new attempts...

    I hand you an idea of a semi-traditional approach of materials (if you are going the manual forming route) of light, strong natural materials such as sustainable woods or bamboo to make strong ultralight well designed cameras... (Cross laminated woods can be VERY stiff done right!!!) That would create interest as a "green" camera, feel traditional, and hopefully could be made/sold cheap enough to get them into many hands...

    Ask ??? here about what we like/hate about our cameras, and do market research... We can be helpful!!!

    Good Luck!!!

    Steve K

  8. #18

    Re: 4x5 Camera

    Quote Originally Posted by LabRat View Post
    Great for trying, but acrylic is heavy for it's strength, not stiff along it's flat surface, can get brittle, can craze from environmental exposure or strain, not internally interlocked, scratches/scuffs without much effort, needs to be cross-supported as thin stuff will bend/flex along it's surface plane, different internal tensions due to harder outer surfaces to slightly softer core, all parts generally have to be hand worked (edges typically burn a little using laser cutter + flat stock), and not really strong cast...

    Now, most makers are forming parts with ABS CNC forming/machining methods, but the internal stiffness and brittle problem still exists for slender pieces (but parts are typically re-inforced with some ribbing)...

    I'm not trying to discourage your efforts, but we have been seeing other attempts using high tech to make new LF cameras (and some failures with cracking and other issues), and in this crowd, many are still using over 100 year old examples of gear that is still going strong... And some good new applications of modern materials such as Walker's Titan, so we are not just poo-pooing any new attempts...

    I hand you an idea of a semi-traditional approach of materials (if you are going the manual forming route) of light, strong natural materials such as sustainable woods or bamboo to make strong ultralight well designed cameras... (Cross laminated woods can be VERY stiff done right!!!) That would create interest as a "green" camera, feel traditional, and hopefully could be made/sold cheap enough to get them into many hands...

    Ask ??? here about what we like/hate about our cameras, and do market research... We can be helpful!!!

    Good Luck!!!

    Steve K
    Thanks a lot for your comment, I appreciate your platitude regarding my attempts to build a camera. All of the issues you've flagged with Acrylic sheet have already been identified and addressed. There are no single large spans (as I'm aware of the inherent flex within acrylic, like all thin sheet materials), any large supporting sections like the main camera bed and uprights, are made up of a number of laminated sheets bolted together for strength and rigidity. I'm not sure if you've ever done any laser cutting of acrylic sheet but there is no burning of the edge or hand finishing required if it's done properly.

    If you take a look at my Kickstarter campaign you will see that this isn't the first camera I've ever built and I've gone through a number of revisions since starting the build 18 months ago. The camera design and functionality has also been compiled following specific feedback from other photographers. I appreciate that many film photographers are still using 100 year old kit, I've also shot with numerous cameras of various vintage (and still do), so am under no illusion that the Chroma is not going to appeal to a photographer who prefers a 'classic' camera. However, that doesn't mean that there isn't room in our photographic ventures for an alternative to the norm.

    With regards to using bamboo, that's an interesting idea. Have you ever built your own camera? It would be good to share your design ideas too. Finally, I'm currently at 93 backers wanting their own Chroma with 3 weeks left on the campaign so I guess there must be demand for an affordable, unique and modern large format camera.

    Steve

Similar Threads

  1. What's This Camera Worth? Rochester Camera & Supply Company Poco B 5x7 Plate Camera
    By unixrevolution in forum Cameras & Camera Accessories
    Replies: 13
    Last Post: 18-Mar-2012, 14:33

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •