Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,549   Posts: 1,544,638   Online: 723
      
Page 3 of 4 FirstFirst 1234 LastLast
Results 21 to 30 of 39

Thread: UV Bliss

  1. #21
    Jeremy's Avatar
    Join Date
    Oct 2002
    Location
    Denton, TX
    Shooter
    Multi Format
    Posts
    2,767
    Images
    56
    It has electronic ballasts and it's quite uniform in illuminsation. I coated a 16x20 sheet of paper and couldn't find any varaitions in the density.
    Let's see what I've got in the magic trash can for Mateo!

    blog
    website

  2. #22
    Murray@uptowngallery's Avatar
    Join Date
    Sep 2003
    Location
    Holland, MI
    Shooter
    Pinhole
    Posts
    1,028
    Sounds great.
    Murray

  3. #23
    Ed Sukach's Avatar
    Join Date
    Nov 2002
    Location
    Ipswich, Massachusetts, USA
    Shooter
    Medium Format
    Posts
    4,520
    Images
    26
    Quote Originally Posted by Murray@uptowngallery
    ... 'Ordinary' acrylic blocks alot, but the curve is so sloppy it's hard to state a percentage of at what wavelength it 'kicks in'. Roughly 70% blockage and I'd assume same wavelength. (Any) glass blocks below 380 nm.
    Murray
    True about "ordinary" glass (~95% - 98%) ... but the composition of "ordinary" (non-coated) acrylics must have changed significantly since I've done spectrophotometry. The most UV I've ever seen attenuated through acrylics was about 5%.
    Carpe erratum!!

    Ed Sukach, FFP.

  4. #24
    Murray@uptowngallery's Avatar
    Join Date
    Sep 2003
    Location
    Holland, MI
    Shooter
    Pinhole
    Posts
    1,028
    I got some literature from Atto-Haas and Cyro on their 'regular' and UF acrylic sheet. I don't remember who said what below...

    1) The UV filtering component is blended into the polymer, not a coating.

    2) They had no data (curves) for UV filtering of 'regular' acrylic because that's not one of the desired properties, but one guy (@ Cyro, if I remember right) said from his measurements it's about 70%, kind of a raggedy curve that creeps into the wavelengths shorter than 400 nm.

    I think part of the question is what wavelengths are being discussed (narrow spectrum or broad band).

    The context for the comparisons I was looking for were for picture framing. It seems most man-made UV sources have 'spikes' at a small number of specific wavelengths. The sun is probably broader (I'm assuming).

    How the acrylic mfrs measure a broad range of wavelengths in the UV range is interesting...maybe there are 'tuneable' UV sources that can be swept across a range of wavelengths...???

    I think the UV filtering specs for glazing materials boil the spectral plot down to %suppression between 265 and 380 nm for glass and 265-400 for acrylic, apparently all glass stopping wavelengths shorter than 260-ish (I don't know the exact number).

    Regular plate glass is advertised (in PF industry) as having roughly 44% UVF. I found even that disappointing where one WANTS UV and needs to flatten materials under glass. I guess it's only a bit more than one stop so you just live with it.

    There is UVT (UV transmitting) acrylic, but I dread to think what it costs, where one can get it, and doubt it's transparent to the visible wavelengths (can't see what's behind it)...maybe one doesn't care if you usually look behind alt-process prints.

    Murray
    Murray

  5. #25
    Murray@uptowngallery's Avatar
    Join Date
    Sep 2003
    Location
    Holland, MI
    Shooter
    Pinhole
    Posts
    1,028
    How has Jeremy Moore's platinum work gone with the blue box?

    Murray
    Murray

  6. #26
    Murray@uptowngallery's Avatar
    Join Date
    Sep 2003
    Location
    Holland, MI
    Shooter
    Pinhole
    Posts
    1,028
    I just realized (did the math), those must be T12 lamps (1.5" diam.) not T8 (1").

    Am I seeing a slight 'herringbone' pattern in the lamp orientation, or is that a snapshot distortion? If so, is this better than even parallel spacing?

    I thould they were BLB lamps. Interesting how blue they look...maybe because I (and the camera) can't see the 365 nm component! (I'm a little slow)

    Thanks

    Murray
    Murray

  7. #27

    Join Date
    Jul 2003
    Location
    Texas
    Shooter
    Multi Format
    Posts
    3,576
    Images
    27
    Quote Originally Posted by Jeremy Moore
    It has electronic ballasts and it's quite uniform in illuminsation. I coated a 16x20 sheet of paper and couldn't find any varaitions in the density.

    Jermey, since this thread has come back up a couple of questions for you..I am putting together everythng to build one of these.

    1. Did you pick up the electronic ballasts local, if so where?

    2. Did you pick up the screw mount bi-pin sockets local or order them, and are they mounted at the base (from the photo that's how it looks).

    Will retire the proto-type when this one is complete.

    Thanks,
    Mike C

    Rambles

  8. #28
    Jeremy's Avatar
    Join Date
    Oct 2002
    Location
    Denton, TX
    Shooter
    Multi Format
    Posts
    2,767
    Images
    56
    Answers coming in reverse order because it was easier to cut-&-paste that way.
    Quote Originally Posted by photomc
    Jermey, since this thread has come back up a couple of questions for you..I am putting together everythng to build one of these.

    1. Did you pick up the electronic ballasts local, if so where?

    2. Did you pick up the screw mount bi-pin sockets local or order them, and are they mounted at the base (from the photo that's how it looks).

    Will retire the proto-type when this one is complete.

    Thanks,
    1. I ordered them online at wherever Ed Buffaloe suggested in his article.
    2. I bought the bi-pin sockets locally at Lowes and screwd them in. The screw does go in at the base--don't do what I did I and to screw too tight. I cracked a couple but they still work just fine.


    Quote Originally Posted by Murray@uptowngallery
    I just realized (did the math), those must be T12 lamps (1.5" diam.) not T8 (1").

    Am I seeing a slight 'herringbone' pattern in the lamp orientation, or is that a snapshot distortion? If so, is this better than even parallel spacing?

    I thould they were BLB lamps. Interesting how blue they look...maybe because I (and the camera) can't see the 365 nm component! (I'm a little slow)

    Thanks

    Murray
    Yes, I just measured them and they appear to be 1.5" in diameter, but I think they are BL bulbs and not BLB bulbs. Some of it is distortion and some of it is the fact that the bulbs are perfectly parallel. After doing an 11x14 test print to check for eveness of lighting I know it's not a problem.

    Quote Originally Posted by Murray@uptowngallery
    How has Jeremy Moore's platinum work gone with the blue box?

    Murray
    Well, it's not platinum, just too dang expensive, but my palladium work is coming along great! Hopefully I will be adding gum bichromate in the next month or so, too.
    Let's see what I've got in the magic trash can for Mateo!

    blog
    website

  9. #29
    Jeremy's Avatar
    Join Date
    Oct 2002
    Location
    Denton, TX
    Shooter
    Multi Format
    Posts
    2,767
    Images
    56
    Mike, if you want to come over and see/try out the box one weekend let me know.
    Let's see what I've got in the magic trash can for Mateo!

    blog
    website

  10. #30

    Join Date
    Jul 2003
    Location
    Texas
    Shooter
    Multi Format
    Posts
    3,576
    Images
    27
    Hey Jermey...Thanks. If mine does not get off the ground, so to speak, will take you up on that. Could not tell from the web site for the Ubiuldit if the ballast were electronic or not. Oh and thanks for the tip about the sockets..know how easy it is to break them. BTW, if you have not picked up a fan, I did find a 4 in. fan at Radio Shack - but $20...was more than I had figured..don't know why..anyway if you don't find one up there let me know and I can pick one up down here.
    Mike C

    Rambles

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