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  1. #11

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    Quote Originally Posted by Roger Hicks View Post
    Dear Eric,

    Why do you need a densitometer? What are you planning to do with it? Consider that densitometers were all but unknown in amateur use until recently, and completely unknown in the early days of photography. Can't you use the time-honoured method of just making pictures, instead? Do not look for more precision than is needed, or meaningful...

    Not being combative, just wondering.

    Cheers,

    Roger
    Hi Roger,
    Since this is the Alternative Process forum, I suspect the densitometer is a time saving device. AFIK, alternative processes need longer (sometimes much longer) exposures. This could make your film testing for speed and development times based on print appearance take quite a long time. It would be much faster if you had a densitometer to simply measure the density on the negative for film testing.

    Dan

  2. #12
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    Quote Originally Posted by dslater View Post
    Hi Roger,
    Since this is the Alternative Process forum, I suspect the densitometer is a time saving device. AFIK, alternative processes need longer (sometimes much longer) exposures. This could make your film testing for speed and development times based on print appearance take quite a long time. It would be much faster if you had a densitometer to simply measure the density on the negative for film testing.

    Dan
    Yep, exactly. I'm starting to do some Kallitype this weekend and I need a "base" starting point. Such as "my negs are x.x density, I have my UV bank of lights, it takes NN minutes for [whatever] exposure". This way, I can guestimate if my density increase x.x+, then perhaps, my exposure can be increased in the same logarithmic. But anyway, its just a base starting point, that's all. So I don't really want to buy one, I just want an effective way of getting some type of measurement in a measurable way.

    So far, I think the GIMP and/or Photoshop method might work (still haven't found the density settings in GIMP), or just basic spotmeter or the ND filter trick. All sounds good.

  3. #13

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    Quote Originally Posted by eric View Post
    Yep, exactly. I'm starting to do some Kallitype this weekend and I need a "base" starting point. Such as "my negs are x.x density, I have my UV bank of lights, it takes NN minutes for [whatever] exposure". This way, I can guestimate if my density increase x.x+, then perhaps, my exposure can be increased in the same logarithmic. But anyway, its just a base starting point, that's all. So I don't really want to buy one, I just want an effective way of getting some type of measurement in a measurable way.

    So far, I think the GIMP and/or Photoshop method might work (still haven't found the density settings in GIMP), or just basic spotmeter or the ND filter trick. All sounds good.
    I wonder if you could use a 21-step wedge and just compare your negative to it in a light table?

  4. #14

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    Quote Originally Posted by dslater View Post
    I wonder if you could use a 21-step wedge and just compare your negative to it in a light table?

    You could certainly do this. One of the Kodak densitometers was based on making exactly this kind of comparison.

    Sandy King

  5. #15
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    Quote Originally Posted by sanking View Post
    You could certainly do this. One of the Kodak densitometers was based on making exactly this kind of comparison.

    Sandy King

    I will have to do some googling and read more about step wedges. I have no idea how to use them.

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  7. #17

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    Quote Originally Posted by eric View Post
    Yep, exactly. I'm starting to do some Kallitype this weekend and I need a "base" starting point. Such as "my negs are x.x density, I have my UV bank of lights, it takes NN minutes for [whatever] exposure". This way, I can guestimate if my density increase x.x+, then perhaps, my exposure can be increased in the same logarithmic. But anyway, its just a base starting point, that's all. So I don't really want to buy one, I just want an effective way of getting some type of measurement in a measurable way.
    Dear Eric,

    Fair enough. But Kallitypes (like all printing-out processes) are self-masking and were traditionally printed by inspection. As long as you have plenty of contrast, you should be OK.

    I've not made Kallitypes but I have made the closely related Argyrotype and although I have two densitometers (a working Heiland and a non-working comparison densitometer from the late 19th/early 20th century) I don't use a densitometer for this purpose. Exposures don't take that long and I find it quicker and easier to 'eyeball' what's happening than to make extensive measurements and calculations. After making a few, you can see what sort of neg will print well and what sort of exposure it will need.

    I fully accept that this is only one way of doing it, and that your route is another, but my feeling is that you'll learn to eyeball it eventually anyway, and that if you do it the traditional way (no densitometer) you may actually acquire that knowledge faster. Just a thought.

    Cheers,

    Roger
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  8. #18
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    Is there some chart I'm unaware of that tells you times based on density? If there was such a chart then I could see a densitometer being useful but for alt process stuff, experience and testing for yourself is the best teacher. If there was such a chart it'd have to incorporate how far from the bank of UV tubes and how powerful the wattage and how many tubes (possibly) etc. A split back frame for printing-out-processes would be infinitely more useful than an expensive gadget and experience will eventually come to you in the long run from actually doing the process rather than reading off pretty little numbers.

    From my experience with using a facial tanner unit with a bank of UV bulbs, exposures take a very long time for my cyanotypes - give me a bright sunny day over the UV box any day. It can mean the difference between 45minutes in front of the box and a maximum of 20minutes outside on a full sunshine day.
    ~Heather
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  9. #19
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    Quote Originally Posted by Roger Hicks View Post
    Dear Eric,

    Why do you need a densitometer? What are you planning to do with it? Consider that densitometers were all but unknown in amateur use until recently, and completely unknown in the early days of photography. Can't you use the time-honoured method of just making pictures, instead? Do not look for more precision than is needed, or meaningful...

    Not being combative, just wondering.

    Cheers,

    Roger
    Roger,

    Your comments are sometimes a true relief, and this remark is NOT sarcastically intended!
    But I do confess, I have one to, but only use my X-rate 882 for E-6 and C-41, for B&W I use the little bit of guts I think I have.
    Alt processes are invented, and used at the time, by trial and error, I believe they should be practised as such, other wise the fun might 'evaporate'. But, of course, this is again a personal opinion (= attitude?)...

    Good Luck,

    Philippe
    "...If you can not stand the rustle of the leafs, then do not go in to the woods..."
    (freely translated quote by Guido Gezelle)

    PS: English is only my third language, please do forgive me my sloppy grammar...

  10. #20
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    I am just calibrating for Platinum and Palladium and am using a stouffer 21 step wedge (see attached pic) I dont have a reflective densometer, but do have a scanner. The image attached is what i have worked out to be my standard printing time ( the left hand gradiant is the one i have determined this on as it is a section of the transparency material i will be using)

    Anyway I was wondering if anyone could help me establish what my density range is and Dmax by just using a scanner and photoshop as i am unsure how to get such readings through a scanned image.

    many thanks
    Attached Thumbnails Attached Thumbnails stouffer.jpg  
    Platinum Printing Editions http://www.dceditions.com
    The Art of Platinum Printing Blog http://artofplatinum.wordpress.com/
    Alternative Photographic Processes blog http://altphotoblog.com/

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