Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,955   Posts: 1,586,017   Online: 670
      
Page 2 of 2 FirstFirst 12
Results 11 to 17 of 17
  1. #11
    Usagi's Avatar
    Join Date
    Apr 2007
    Location
    Turku, Finland. Northern Europe.
    Shooter
    Multi Format
    Posts
    360
    Images
    18
    Now it's hot here, my darkroom has 28 degree celcius. Just realized one weak point of motorized orbital: No way to use waterbath, so I cannot control developing temperature.

    Perhaps I should develop with keeping tray in the waterbath and by rocking it... The motor is just - so ease.

  2. #12
    Usagi's Avatar
    Join Date
    Apr 2007
    Location
    Turku, Finland. Northern Europe.
    Shooter
    Multi Format
    Posts
    360
    Images
    18
    A bit more about Orbital.

    I got some time ago first negative that was developed unevenly. The edges of 4x5 negative had notably more density than other areas.
    As this was real world photograph, I didn't measure it more, but I took some test negatives. Target was evenly illuminated wall from very close distance, camera focused on infinity.

    What I found was significantly more density around the edges of the negatives. This was same with my both orbital tanks - one that has "dremel worked" and one that has silicon droplets.

    Now, after I have looked issue more, I suspect that the cause could be change in the movement pattern.
    My orbital used to rotate and tilt the tank. The tank rotated slowly on each turn of the motor base and got tilted on each turn (here's a youtube video).
    Now it only does tilting movement, rotation is gone.
    I haven't yet figured out what caused that and why my tanks have lost that rotation movement. Is there too much or too less friction?


    How do your Orbital move with motor? Is the pattern similar like in the youtube video? If it is, then that is really the reason for my problems and I have to fix either motor base or go to the manual agitation.

  3. #13
    bill spears's Avatar
    Join Date
    May 2007
    Location
    Cornwall England
    Shooter
    Multi Format
    Posts
    565
    Images
    31
    This looks like too much agitation for me, and potential developer spill, although I know others use this method with no problems.
    I used to fill with alot more solution so that the film is practically covered then agitate very gently by hand - similar to as you would with paper.

  4. #14
    Usagi's Avatar
    Join Date
    Apr 2007
    Location
    Turku, Finland. Northern Europe.
    Shooter
    Multi Format
    Posts
    360
    Images
    18
    Wirelessly posted (Samsung 2700: SAMSUNG-B2700/XBIB2 SHP/VPP/R5 NetFront/3.4 SMM-MMS/1.2.0 profile/MIDP-2.0 configuration/CLDC-1.1)

    The motorized agitation works at least up to 350ml when the lid is closed.

    My guess is that rotation movement broke the developer flowing pattern and prevented uneven development.
    Now when my motor base does not do rotation pattern any more, only tilts tank in (one direction) about 3 seconds intervals, it is just too much and flowing pattern istoo simple and predicable.
    So it is like tilting towards every corner so that one full 'circle' takes circa 3 seconds.

    Manual rocking surely works, but then my biggest fear is possible too strong development near the edges of the tank where moving developer bounces back.

    Haven't done much testing with manual rocking though. However when doing traditional tray developing by rocking the tray, too strong edge density is often problem - like i have now with 'tilting only' motor base.
    Last edited by Usagi; 08-13-2009 at 04:59 PM. Click to view previous post history. Reason: typing errors...

  5. #15
    Steve Smith's Avatar
    Join Date
    May 2006
    Location
    Ryde, Isle of Wight
    Shooter
    Medium Format
    Posts
    8,722
    Images
    122
    Quote Originally Posted by Usagi View Post
    Now it's hot here, my darkroom has 28 degree celcius. Just realized one weak point of motorized orbital: No way to use waterbath, so I cannot control developing temperature.

    Actually, I think you can. I have read reports of people dispensing with the motor or static base and floating the tray in a bath of water to maintain temperature.


    Steve.
    "People who say things won't work are a dime a dozen. People who figure out how to make things work are worth a fortune" - Dave Rat.

  6. #16
    Usagi's Avatar
    Join Date
    Apr 2007
    Location
    Turku, Finland. Northern Europe.
    Shooter
    Multi Format
    Posts
    360
    Images
    18
    Here's video example how my orbital does agitation now. In the end of the video I use hand for doing rotating movement like my orbital used to do.
    Which way is the proper for orbital with motorized base?

    http://jukkavuokko.com/linkatut/CIMG...nly%20tilt.avi


    I also did some tests with much less developer and found out that uneven developing was not any more a problem. It seems that as I have slowly begun to use more and more developer (up to 300-350ml), it ruins the whole idea behind the orbital, which is to use only small amount of developer but move it fast over the surface.
    Seems like 150ml is okay, perhaps 200ml also which I have used for a long time.

    Still not sure about the proper agitation with motorized base...

  7. #17
    paul_c5x4's Avatar
    Join Date
    Apr 2009
    Location
    Ye Olde England
    Shooter
    Large Format
    Posts
    1,567
    Images
    26
    For the last few weeks, I've taken to processing single sheets of 5x4 in the centre of the Paterson tray. I'm kinda hooked on the results of semistand development in 200ml of Perceptol at 1:4. Also getting good results on the motorised base, again with a single sheet & 160ml of dev.

Page 2 of 2 FirstFirst 12


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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