Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,859   Posts: 1,583,126   Online: 845
      
Page 3 of 4 FirstFirst 1234 LastLast
Results 21 to 30 of 33
  1. #21
    Tony Egan's Avatar
    Join Date
    Oct 2005
    Location
    Sydney, Australia
    Shooter
    Multi Format
    Posts
    1,137
    Images
    69
    Quote Originally Posted by MartinP View Post
    This idea of using the downlight/spotlight things is great and I/m now thinking of a high-power version of a Varicon head.

    However, I'm wondering about the distance from the condenser (via the mirror) -- shouldn't the illuminated surface be on the former centreline of the bulb, in order to be concentrated optimally by the condenser(s) ? With any luck there is so much light power available that this isn't a problem, but it might make a difference at extremes.

    I'm also curious about the turn-on delay of the unit. Does the enlarger keep the bulb on all the time and have a shutter for exposures?
    Re the turn on delay, yes there is a fraction of a second delay but much less than dry down effect so not something I agonise over! It is not unusual for variations in the mains supply to visibly change the light output from the bulb in any case, so I think the output from a 12v source may in fact be more consistent. I make a small adjustment to my starting exposure on the first print based on the number of exposures on the test strip but I think this is immaterial given my final print is usually version 4 or 5 after time and contrast adjustment, dodge, burn etc etc.

    There is no shutter. Light goes on and off via an RH timer in my case.
    Last edited by Tony Egan; 04-03-2013 at 05:49 PM. Click to view previous post history. Reason: Addnl info
    http://www.tonyeganphotography.com/index.html
    "Those are my principles, and if you don't like them... well, I have others." Groucho Marx

  2. #22

    Join Date
    Jun 2007
    Shooter
    35mm
    Posts
    1,051
    Thank you for the extra info. Since I posted (of course!) I have found there are different LED-driver modules which have different startup times, so you have wisely chosen a quick one.

    Actually, I'm not completely sure that the heater element in my kitchen-grill uses any more power than that 300W bulb in the original Durst head

  3. #23

    Join Date
    Feb 2003
    Location
    Jacksonville, FL
    Shooter
    Large Format
    Posts
    1,652
    Any problem with converting a Pavelle Color light head that's for a Durst L1000 into using LED light(s)? I have two of the heads, and was thinking of converting the current spare. It sure would be quieter in the darkroom without the fan running ;-)
    van Huyck Photo
    "Progress is only a direction, and it's often the wrong direction"

  4. #24

    Join Date
    Jan 2008
    Shooter
    Med. Format RF
    Posts
    114

    Re: LED light conversion on Durst Laborator 138

    Quote Originally Posted by pcyco View Post
    hallo

    the worst thing is the diffusor (plexiglass).
    i think it absorbs to much light i think i will look for something thinner. any foil etc. thinner and less absorbing light.
    @ martinp: yes i have located the laamp in the axxis of the lighthole with the heatabsorbingglass. aprox. 3 cm away from the diffusorplexi in the filterdrawer.

    --
    thomas
    I don't know the proper word in english, but I use a piece of paper that we would call (translated) "chalk paper". It is also used to copy a picture or drawing by following it with a pencil; it's semi-transparant. Works very well and does not take too much light away (about one stop).

    Stefan

    Verstuurd van mijn GT-P7510 met Tapatalk

  5. #25
    MattKing's Avatar
    Join Date
    Apr 2005
    Location
    Delta, British Columbia, Canada
    Shooter
    Multi Format
    Posts
    12,927
    Images
    60
    Quote Originally Posted by gliderbee View Post
    I don't know the proper word in english, but I use a piece of paper that we would call (translated) "chalk paper". It is also used to copy a picture or drawing by following it with a pencil; it's semi-transparant. Works very well and does not take too much light away (about one stop).

    Stefan

    Verstuurd van mijn GT-P7510 met Tapatalk
    In English, it is known as "tracing" paper.
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  6. #26
    Tony Egan's Avatar
    Join Date
    Oct 2005
    Location
    Sydney, Australia
    Shooter
    Multi Format
    Posts
    1,137
    Images
    69
    Quote Originally Posted by gliderbee View Post
    I don't know the proper word in english, but I use a piece of paper that we would call (translated) "chalk paper". It is also used to copy a picture or drawing by following it with a pencil; it's semi-transparant. Works very well and does not take too much light away (about one stop).

    Stefan

    Verstuurd van mijn GT-P7510 met Tapatalk

    Also "Drafting film" used for architectural plans and drawings is a bit more resilient than plain "Tracing paper". I can buy it in single sheets from arts supplies stores in my city. I use drafting film as a diffuser in the enlarger I use for flashing and it works well
    http://www.tonyeganphotography.com/index.html
    "Those are my principles, and if you don't like them... well, I have others." Groucho Marx

  7. #27
    Tony Egan's Avatar
    Join Date
    Oct 2005
    Location
    Sydney, Australia
    Shooter
    Multi Format
    Posts
    1,137
    Images
    69
    Quote Originally Posted by doughowk View Post
    Any problem with converting a Pavelle Color light head that's for a Durst L1000 into using LED light(s)? I have two of the heads, and was thinking of converting the current spare. It sure would be quieter in the darkroom without the fan running ;-)
    Hi, I'm not familiar with that enlarger but looking at images it appears to have a much smaller lamp housing than the 138 but I'm sure with a bit of tinkering you could make it work without doing permanent damage!
    http://www.tonyeganphotography.com/index.html
    "Those are my principles, and if you don't like them... well, I have others." Groucho Marx

  8. #28

    Join Date
    Jul 2007
    Location
    near vienna
    Shooter
    Multi Format
    Posts
    429
    Images
    74
    hallo

    im working in an architecture office but we dont have tracing paper anymore.
    only computers. but aut home there is a lot. thankyou for the input.
    --
    pcyco
    --------------------------------------------------
    vfdkv (259)

  9. #29

    Join Date
    Apr 2010
    Location
    Hickory, NC
    Shooter
    4x5 Format
    Posts
    32
    Quote Originally Posted by jon.oman View Post
    Would this work with an Omega D2v?
    LED light sources for the Omega D series enlargers are available from my website.

    www.modernenlargerlamps.com

    Cemil

  10. #30

    Join Date
    Mar 2013
    Location
    Italy
    Shooter
    Large Format
    Posts
    21
    I wrote to Ilford some weeks ago about led illumination and use of multigrade ilford filters and this is the answer:

    "First the good news! I believe that the ban on tungsten bulbs in Europe only extends to domestic bulbs. Equipment and specialist lamps are not included - yet. If you are using the Multigrade filters I would recommend using tungsten light as the filters were designed using the "black body-ish" wavelength range of tungsten. LED outputs are always going to be spiky! Filters and white LED will work to some extent but the 1/2 grade spacings may be compromised in interesting and challenging ways and I would expect a reduced contrast range (potentially similar as for people who have tried to use fluorescents and MG filters). The degree of difference will depend on the output of the LED used. It is possible that a particular LED will be such a good match that it works almost as well as tungsten. This would only be found by trying it. Also, your english seems excellent. Please reply to this email with any further questions."

    What do you think?

Page 3 of 4 FirstFirst 1234 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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