Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,550   Posts: 1,544,816   Online: 1013
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 17
  1. #1
    mooseontheloose's Avatar
    Join Date
    Sep 2007
    Location
    Kyoto, Japan
    Shooter
    Multi Format
    Posts
    1,704
    Images
    39

    Using a Crown Graphic - a few questions

    So I'm ashamed to say that I've had my lovely Crown Graphic for over a year now and have not used it in all that time. (teachers are busy!) But I'm going to rectify that this week as I am now temporarily unemployed for a few months and have the time to really play with it. I've pulled it out and have been going over it, really thinking about what I need to do to shoot properly with it. I've done some research about Crowns (and other press cameras), but most information about large format largely ignores press cameras (due to their limited movements), and specific information about the camera just focuses on various parts of the camera, or shooting film with it. But there's so much more to it that that -- I haven't found any real information to help me with the following problems:

    1. I have a top-mounted Kalart rangefinder on the camera which seems to be working and calibrated to my lens (135mm Optar). I know where the battery compartment is, but can't seem to open it -- pressing on either side of the 'door' does nothing, or both sides together, trying to slide it, etc... Am I missing something here? Although it's working I'd like to get in there to make sure there's no corrosion since I have no idea how long the battery has been in there.

    2. I've just figured out (from a few posts and one guy on youtube) that once you open the camera you should pull the camera out to the infinity stops. Is that right? Is that only for the rangefinder calibration or is it necessary for making the best use of the lens?

    3. If I don't extend the bellows beyond the length of the 6' focus marker, do I need to worry about bellows extension exposure? Do I need to worry about it if I extend the bellows to the end of the bed? If I do, is the measure from the ground glass, or the infinity stop?

    4. Finally, the side shutter release (the one that would allow me to do 'press-style' photography) will not depress the shutter button fully -- it only goes about halfway. Is there a way for me to fix this simply, or will I just have to rely on the lens shutter?

    I've had some very limited experience with view cameras in the past, but not enough to help me with this. I'd appreciate any help people can offer.
    Rachelle

    My favorite thing is to go where I've never been. D. Arbus

  2. #2
    jbbooks's Avatar
    Join Date
    Apr 2005
    Shooter
    Multi Format
    Posts
    173
    http://graflex.org/

    1. Depress one end and use a very small screwdriver to push the cover towards the depressed end, releasing the pushed end.

    2. The infinity stops are for extending the lens to the point where the camera is focused at infinity and allows the rangefinder to focus properly with the proper cam. With the camera focused at infinity and the rangefinder calibrated properly, the distance scale can be adjusted, if necessary, to correctly indicate distances at less than infinity.

    3. http://www.largeformatphotography.in...ead.php?t=7574

    4. Look at the threaded extension of the cable end and the linkage for the means of adjusting the length of .
    movement of the lever that trips the shutter.

  3. #3
    jbbooks's Avatar
    Join Date
    Apr 2005
    Shooter
    Multi Format
    Posts
    173
    A little more on the cover. If it is in place, it is held there by spring pressure against the battery or a small wood block that was supplied with the camera in place of the battery. You can press the whole cover in slightly and, when you do, you can push against the edge of one end with the screwdriver tip.

  4. #4
    Christopher Walrath's Avatar
    Join Date
    Dec 2005
    Location
    Milton, DE, USA
    Shooter
    4x5 Format
    Posts
    6,980
    Blog Entries
    29
    Images
    19
    Posted wirelessly..

    3. The quickest way to figure bellows extension I have found is to use the following equation. Exposure adjustment = extension length squared / focal length squared. Example: you have a 6" lens extended to 11". Your exposure adjustment would be 11 sqd / 6 sqd, or 121/36. This would be about 3.3. Increase exposure by 3 to 3.5 stops.
    Thank you.
    CWalrath
    APUG BLIND PRINT EXCHANGE
    DE Darkroom

    "Wubba, wubba, wubba. Bing, bang, bong. Yuck, yuck, yuck and a fiddle-dee-dee." - The Yeti

  5. #5
    TheFlyingCamera's Avatar
    Join Date
    May 2005
    Location
    Washington DC
    Shooter
    Large Format
    Posts
    8,365
    Blog Entries
    51
    Images
    437
    Chris- I think you're grossly overcompensating for bellows extension. At 1:1 bellows extension, exposure compensation is 2 stops. At 1:2, it is 1 stop. IE, if your 6" lens is extended to 12", you apply 2 stops exposure compensation. At 9", it is 1 stop.

  6. #6
    Christopher Walrath's Avatar
    Join Date
    Dec 2005
    Location
    Milton, DE, USA
    Shooter
    4x5 Format
    Posts
    6,980
    Blog Entries
    29
    Images
    19
    Actually, I thought I was as well when I read it. I did have the correct equation, didn't I? But I double checked the math and it can't be right. So I retract the previous statement and, in absence of literature, I will go back to sleep now. ;p
    Thank you.
    CWalrath
    APUG BLIND PRINT EXCHANGE
    DE Darkroom

    "Wubba, wubba, wubba. Bing, bang, bong. Yuck, yuck, yuck and a fiddle-dee-dee." - The Yeti

  7. #7
    TheFlyingCamera's Avatar
    Join Date
    May 2005
    Location
    Washington DC
    Shooter
    Large Format
    Posts
    8,365
    Blog Entries
    51
    Images
    437
    light falls off in the camera at the same ratio that it does outside. It's an inverse square relationship: +2x the distance equals -4x the light.

  8. #8
    Christopher Walrath's Avatar
    Join Date
    Dec 2005
    Location
    Milton, DE, USA
    Shooter
    4x5 Format
    Posts
    6,980
    Blog Entries
    29
    Images
    19
    Posted wirelessly..

    Got it. 1.4 the bellows extension. One stop. 2 the bellows ext. Two stops. 2.8 (roughly) the bellows ext. Three stops. And so on. Duh.
    Thank you.
    CWalrath
    APUG BLIND PRINT EXCHANGE
    DE Darkroom

    "Wubba, wubba, wubba. Bing, bang, bong. Yuck, yuck, yuck and a fiddle-dee-dee." - The Yeti

  9. #9

    Join Date
    Apr 2004
    Location
    Montgomery, Il/USA
    Shooter
    Multi Format
    Posts
    5,097
    1) Sometimes old batteries have leaked & make removal of the batt. cover difficult.
    2)Extending the lens to the stops allow the rf to work with that lens.
    3)from the infinity stop. The stop marks the FL at infinity so any extension is calculated from that point.
    4)The side shutter release engages the shutter's release lever As David says, it's adjustable.

    The easiest way I've found to deal with bellows factor is with memory(mine). Flying camera has it when he says 2X FL = 2 stops, 1.5X = 1 stop. Anything between can be estimated. If you're going beyond 1:1, you will be better off doing the math. Depending on the film will need to allow for reciprocity effect.
    Heavily sedated for your protection.

  10. #10
    jbbooks's Avatar
    Join Date
    Apr 2005
    Shooter
    Multi Format
    Posts
    173
    Regarding number 3, perhaps this is more responsive to your question:

    On mine, the length of the bellows extension is easiest to measure by measuring the distance from the rear edge of the camera body, where the film holder face rests when it is inserted, to the face of the shutter dial. Again, on mine, with an Optar 135mm in a Graphex shutter with the lens focused at infinity, that distance is as close to 135mm as makes no difference.

Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin