Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,765   Posts: 1,516,375   Online: 1028
      
Results 1 to 4 of 4
  1. #1
    Steve Smith's Avatar
    Join Date
    May 2006
    Location
    Ryde, Isle of Wight
    Shooter
    Medium Format
    Posts
    8,531
    Images
    122

    Graflarger Back - Aristo Light Source Advice

    I have just received a Graflarger back with Aristo light source from Ebay for the sum of £0.99 ($2).

    I was expecting it not to work and intended to convert it to LED however, it does work so I may keep it as it is for now although I may replace the transformer for one with a 230v primary.

    I have measured the AC output of the transformer and when powered up it starts at 580, rises to 650 then drops and stabilises at 630. I have some valve amplifier HT transformers which would give me around 500 - 600 volts so I will probably try one of those.

    Can anyone tell me if it will produce light connected directly to 230 volts or does it need a higher voltage to start?

    It does not have the negative carrier which isn't a great problem as I have use of a CNC router so I can easily make another one (and options for smaller formats).

    If anyone has one of these, I would appreciate it if you could tell me the distance the negative sits from the diffuser and the overall thickness of the holder. I measure the slot at 5.5mm (7/32").

    Thanks.



    Steve.
    Last edited by Steve Smith; 07-25-2008 at 03:02 AM. Click to view previous post history.

  2. #2
    Nicholas Lindan's Avatar
    Join Date
    Sep 2006
    Location
    Cleveland, Ohio USA
    Shooter
    Multi Format
    Posts
    2,372
    Images
    4
    The 'transformer' is also the ballast, and has two functions: raise the voltage; and regulate the current. You can't replace it with a regular HT transformer without getting into a lot of trouble with the lamp - though you could arrange your own ballast. If it is a 115 V Graflarger the easiest solution is to use it with a 230->115V step down transformer. Performance will be a bit different because of the 50 Hz frequency (lamp current will be 17% higher than it should be) but it shouldn't make that much difference.
    DARKROOM AUTOMATION
    f-Stop Timers - Enlarging Meters
    http://www.darkroomautomation.com/da-main.htm

  3. #3
    Steve Smith's Avatar
    Join Date
    May 2006
    Location
    Ryde, Isle of Wight
    Shooter
    Medium Format
    Posts
    8,531
    Images
    122
    Thanks for the information. I didn't really want to use it with a step down transformer but since my LPL enlarger is also 110 volt and I already have a transformer, it's not too much of a problem. I didn't realise there was more to it than just a transformer though.


    Steve.

  4. #4
    David A. Goldfarb's Avatar
    Join Date
    Sep 2002
    Location
    Honolulu, Hawai'i
    Shooter
    Large Format
    Posts
    17,140
    Images
    20
    The negative carrier consists of two aluminum frames that together are just shy of 3/16".

    Aristo will still update the bulb, if you want.

    Like other old-style cold light heads that don't have a heating circuit, the output of the bulb varies noticably, particularly if you are trying to make lots of prints with a short exposure time, like a batch of postcards. If you don't have a compensating timer like a Metrolux, you might want to use an enlarging lens that can be put in a shutter to control exposure time, or use a black card over the lens, so you can leave the lamp on.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
    Photography (not as up to date as the flickr site)--http://www.davidagoldfarb.com/photo
    Academic (Slavic and Comparative Literature)--http://www.davidagoldfarb.com



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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