Which stouffer step wedge?

Discussion in 'Darkroom Developing and Printing' started by Nick Zentena, Sep 16, 2003.

  1. Nick Zentena

    Nick Zentena Guest

    I'm about to order a step wedge. The main reason will be to
    calibrate the densitometer I bought. I think I also want it to contact print
    onto film/paper for the odd test. So which one should I get? The transmission
    one seems to make the most sense. Calibrated isn't much more money. If I get
    the 4x5 it seems that it should do everything I need. Of course I'm likely
    missing something. So is there a better choice?


    Thanks
    Nick
     
    Nick Zentena, Sep 16, 2003
    #1
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  2. I think the calibrated is a waste because you will still need to read it
    on your equipment. 4x5 Stouffer Wedges are OK but in my experience
    Kodak wedges are much better because the Stouffer wedges I have seen
    vary in density from place to place within the individual steps. Which has not
    been my experience with Kodak Uncalibrated wedges,....I have used the 4x5 & 8x10
    Stouffer wedges....8x10 is a good size if your doing multiple tests on paper
    I striped Kodak Poly contrast filters onto a sheet of glass and taped the wedge
    to the other side EM down, then that enabled me to make multiple tests on one sheet
    of print paper ,with one exposure and one development cycle (For determining paper
    speeds and such for multi contrast paper).

    4x5 is the best size for film contrast testing if you are a 4x5 shooter. For practical
    purposes the Stouffer wedges should suit your needs.

    Hope this is found to be useful.
     
    Gregory W. Blank, Sep 16, 2003
    #2
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  3. Nick Zentena

    Nick Zentena Guest

    Ya but isn't that how I calibrate the densitomer? I fiddle with the knob
    until the display comes close to reading the right number. I was thinking it
    would be better to calibrate with a known good source.


    One thing I want to do is try and figure out how to develop the lith film
    I got. If I'm ever going to get an 8x10 it's the only film I'll be able to
    use enough to justify the camera. OTOH it's not exactly normal contrast.
    I've got a developer formula that supposedly tames the film but it still
    leaves my processing to screw things up.
    Yes.

    Thanks
    Nick
     
    Nick Zentena, Sep 16, 2003
    #3
  4. Actually the Speedmaster Densitometer I used for a time was calibrated
    with its own specific calibration negative, although I don't know if this
    is the case for other densitometers, I would suppose you could do it in the manner you
    describe, but I would read what the densitometer manual states.
     
    Gregory W. Blank, Sep 16, 2003
    #4
  5. All the MacBeth transmission densitometers came with a calibrated
    density chip; my present TD-901 came with a density of 3.04
     
    Jean-David Beyer, Sep 16, 2003
    #5
  6. Nick Zentena

    Sherman Guest

    My Speedmaster came with a reflection target to calibrate the reflection
    part but it requires a calibrated step wedge to calibrate the transmission
    part. I bought a Stouffer wedge and it worked well.

    Sherman
    http://www.dunnamphoto.com
     
    Sherman, Sep 16, 2003
    #6
  7. Well there you have it, it works :)

    Thankfully the Speedmaster calibration neg we (Omega) bought
    was not funded with my pay.....I think it was some ridiculous sum
    like $45-65
     
    Gregory W. Blank, Sep 17, 2003
    #7
  8. That sounds about correct, my understanding is that 3.00
    is about the maximum density film can retain.

    Adjacent to the thread,... at one point Kodak supplied a wide variety
    of wedges some were rather pricey I'll have dig out that old book to
    see what the upper limit was.
     
    Gregory W. Blank, Sep 17, 2003
    #8
  9. Oh no! You can get much more density from most films (not including
    Panatomic X) if you expose them enough and develop them long enough.

    But for normal printing, net densities greater than 2 make little sense.
    The TD-901 is intended for graphic arts work and will read up to a
    density of 4.0 with no trouble. It will give readings higher than that,
    but I would not trust them very much.

    I stuck an aluminum plate in the aperture (about 0.040" thick) once to
    see what the maximum density it could indicate was. I doubt there was
    significant x-radiation from the light source, and further doubt there
    was much x-ray sensitivity from the detector (but I could be wrong about
    that), but the density just kept going up, and somewhere around 6, IIRC,
    I gave it up.
     
    Jean-David Beyer, Sep 17, 2003
    #9
  10. Nick Zentena

    Sherman Guest

    Those things *are* expensive! Even the Stouffer wedge I got was around $20
    with shipping. It is calibrated but not certified. Close enough for
    government work (and for me).

    But on the other hand I got the densitometer on eBay then emailed
    Speedmaster to see if I could get a manual since the seller didn't have one.
    The model I have is not current. They emailed me back on the same day
    asking for my mailing address and three days later I had a manual at no
    charge! I even said in my original email I was willing to pay for the
    manual and shipping. Great customer service and I wasn't technically a
    customer!

    Sherman
    http://www.dunnamphoto.com
     
    Sherman, Sep 17, 2003
    #10
  11. But for reversal work densitys up to ~ 3.7 will be used.
    I made tests with a X-Rite 820 colour densitometer. It is specified for
    transmission densitys up to 4.0. But at density 3.5 first differences
    between readings an mean densitys greater than the tolerance appears.
    At higher (4-6) mean-densitys the differences get worse - but only in one
    colour.

    I load the diagramms up to:
    http://www.keinaths-fotohomepage.gmxhome.de/Extras/Densitest.htm
    Sorry, ist´s only provisional.

    Markus
     
    Markus Keinath, Sep 17, 2003
    #11
  12. Gregory W. Blank, Sep 18, 2003
    #12
  13. That seems to be a change in policy although it could be because the unit is NLA
    I ended up buying a copy for Omega somewhere around $20-30
    at the time.
     
    Gregory W. Blank, Sep 18, 2003
    #13
  14. Well I'll have to give that a shot,....mental note develop film until bullet proof
    or otherwise cannot be printed ;-)
     
    Gregory W. Blank, Sep 18, 2003
    #14
  15. Nick Zentena

    QuestionMan Guest

    Wich one do you want to buy?
     
    QuestionMan, Sep 18, 2003
    #15
  16. Nick Zentena

    Nick Zentena Guest


    Either TP4x5-21 or the 31 step one. Likely the 21 step calibrated one.

    Nick
     
    Nick Zentena, Sep 18, 2003
    #16
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