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  1. #71
    dwross's Avatar
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    Quote Originally Posted by jnanian View Post
    i realized early on into this thread that i was saying "ortho" when i meant something different ..
    i meant blue sensitive ( only!) orthochromatic ( not sensitized with dye ) film, like pre-1870s plates ... the baseline .
    at present i am shooting paper negatives, a lot of them, and i was wondering if there was a
    film equivalent to my paper negatives ... some of the papers i shoot are vc, and some are graded..
    i also do some UV exposures, ... so in the end maybe just a bluish ( i will have to experiment, dark , light, greenish/cyanish )
    and filter might works best.

    as chemical photography marches forward, it seems that we are going backwards at the same time ..
    i kind of hope that down the road there is a manufacturer of just plain old blue sensitive ortho film / plates
    instead of pan film. i know it is inferior, and difficult to harness the contrast, and "deal with" because
    of its slowness ( dyes increase the speed ) but it would be kind of nice to see a drastic change.
    instead of chemical photography trying to keep up all the BS that the digi folks want us to worry about,
    ( we've already lost color image making to the computer ) i'd like to hunker down
    and get back to the roots of photography. i know i am probably a minority,
    but images from that early time period seem to be much more interesting than
    things made in the last 100 years ...

    thanks again for all your help, suggestions and information / education ..
    john
    re 'vocabulary words' :

    Over the last 130 years there has been an evolution in naming. Back in c.1880, when plates went from wet to dry, the gelatin emulsion was still UV-only sensitive, and plates were called either 'dry' or 'gelatine'. Soon after, when ortho plates were developed, the UV-only sensitive plates were called 'ordinary' or sometimes 'colorblind' to distinguish them. 'Colorblind' is the most common term to have traveled down the time stream, and it's the one I favor. Colorblind emulsions are beautiful and actually quite different from ortho, which in turn have their own beauty. It is very appropriate to think of each type of emulsion, including sub-categories of each, as different tools for different circumstances. It's a shame we've lost so many commercial options. Hopefully, some of the smaller film companies will recognize a viable niche market. (And, of course, you can always make your own. I'll be teaching how at the Photographers' Formulary in June )

    Denise
    www.thelightfarm.com

  2. #72
    hrst's Avatar
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    Quote Originally Posted by ath View Post
    No, this filter is advertized as blue filter for b&w and not as correction filter. This is from Heliopan using Schott glass. Older B&W filter catalogs show similar curves for the blue filter.
    I found much narrower response for wratten gel filters but even these went up to 500nm. IDK if these are available as glass filters.
    Well, you are right; this is very problematic terminologically. As described before about human vision, words of colors can mean many different things, and all that matters is the shape of the absorption spectrum; the curve of response to different wavelengths. In this case, "blue" can mean many things. More descriptive words are used such as light blue, deep blue, dark blue etc., but they are not much of help. You really have to know what you buy by checking the absorption spectrum plot.

    I wouldn't call the plot you showed blue! It's so light. It could be light blue, but definitely not blue. But, OTOH, it is not called blue - it's called "blau 38". It is a product name that must be thought as such.

  3. #73
    Claudia Moroni's Avatar
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    Quote Originally Posted by hrst View Post
    "Ortho" film usually means it IS spectrally sensitized (with sensitizing dye) for green wavelengths, in addition to blue. Non-sensitized emulsion is blue-sensitive only. Those are also available for some special purposes such as copy films as mentioned before in this thread.
    Quote Originally Posted by CBG View Post
    Among other consequences, all that means that to mimic a plain emulsion with a pan film and filters, use a blue filter. To mimic an ortho emulsion, use a cyan filter which passes blue and green.
    Sorry to mix things up, but I'm rather confused.
    I'd like to simulate non-sensitized emulsion (like wet plate collodion) with an ortho emulsion, which filter should I use? From what has been said, I understand that I could achieve the same effect with a panchromatic film and a deep blue filter like a 47b, but I haven't quite understood what filter is best with orthochromatic emulsion...if anyone could shed some light on the matter, I'd be extremely grateful

    I was also wondering if anyone had any experience developing Ilford Ortho Plus with Rollei Low Contrast developer for pictorial use. I took a couple of portraits in the studio, exposing the film at 50 iso and I can't find info on this combination anywhere

    Thanks

  4. #74
    Photo Engineer's Avatar
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    If you have an pan emulsion, it is almost impossible t create an ortho emulsion!

    PE

  5. #75

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    Quote Originally Posted by Claudia Moroni View Post
    Sorry to mix things up, but I'm rather confused.
    I'd like to simulate non-sensitized emulsion (like wet plate collodion) with an ortho emulsion, which filter should I use? From what has been said, I understand that I could achieve the same effect with a panchromatic film and a deep blue filter like a 47b, but I haven't quite understood what filter is best with orthochromatic emulsion...if anyone could shed some light on the matter, I'd be extremely grateful

    I was also wondering if anyone had any experience developing Ilford Ortho Plus with Rollei Low Contrast developer for pictorial use. I took a couple of portraits in the studio, exposing the film at 50 iso and I can't find info on this combination anywhere

    Thanks
    hi claudia:

    http://www.gommamag.com/v5/files/img...o_plus_web.pdf
    the data sheet says it is safe with a dark red light,
    so you can process your film in your developer and turn the safelight on ... and develop by inspection.
    since this film is important for your project, i would probably shoot a roll or few sheets as guinea pigs
    and process them first as test sheets to figure out the best times and then process your project film.

    i wish i could help you with your filter recommendation !
    i never followed through with any of the suggestions given in this thread ...
    but i think a "bluish" filter might do the trick ...
    i get my ortho results mostly by shooting paper negatives
    i haven't used ilford direct positive paper, maybe it would work for you ?
    it is pretty contrast-y so you might have to flash it, and / or process it in a dilute
    and spent / used / less active developer ... maybe it will do what you need ?
    ... what i do is abuse the film i already have ..
    i over expose it and then over develop it so it is pretty much BULLETPROOF
    and then ... i make contact prints on regular old photo paper using a 300 watt light buib.
    i process both my film AND prints in the same coffee based developer. i use robusta sumatra beans
    and add a wee bit of ansco 130 print developer in it ... but the cheapest of instant coffees will work and whatever print developer
    you have on hand that might be gasping for life ... just make it strong, and add a bit extra soda and enough vit c to make it foam ...
    (add the print developer last )

    my methods aren't for everyone ... maybe a blue filter, paper negatives or ilford direct positive paper works better?
    not sure, but what i do seems to do the trick for me right now ...

    good luck with your project !
    john
    Last edited by jnanian; 02-11-2013 at 02:05 AM. Click to view previous post history.
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  6. #76
    Claudia Moroni's Avatar
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    Thanks for your advice, but I may have to just guess the time as I don't have the facilities to develop by inspection at home.

    I exposed the ortho film without any filter, so it should look rather "normal"...probably like a panchromatic film with a green filter on.

    I just got a bargain minus red filter on ebay and I'll try it as soon as it arrives to see how it works with ortho film, but, from what I've been told, I may as well have bought normal panchromatic film to test with that filter as the effect would be the same. To have a blue sensitivity only effect with the ortho film, I guess I could just cut the green wavelength with a magenta filter, but they're not very common.

    These are just some experiments, I'm shooting my main project on Foma 100 developed on Microphen, so there's no risk of messing up important work I'll keep you updated with my results if you wish x

  7. #77

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    (Ilford Ortho Plus in Rollei RLC)

    Quote Originally Posted by Claudia Moroni View Post
    Thanks for your advice, but I may have to just guess the time as I don't have the facilities to develop by inspection at home.
    Here's what I'd do for a starting point, for what it's worth, based on info from the MDC:

    Rollei Ortho 25 at box speed in Rollei RLC 1+4: 8 minutes...
    ...so let's try to compare the responses in different developers of Rollei Ortho 25 and Ilford Ortho Plus. There's not much in common to go on, unfortunately, due to the limited range of films with times given for RLC.

    Rollei in D-76 stock: 6 minutes
    Ortho Plus in D-76 stock: 8 minutes

    So that suggests, very very very loosely, that Ortho Plus is about 33% "less responsive" than the Rollei film. It would follow that it might need around 10 1/2 minutes (8 minutes times ~1.33) in RLC 1+4. That's at box speed, which is supposed to be 80 in daylight, 40 in tungsten---I don't know what your lighting was, but you might fiddle that time to compensate one way or the other since you exposed at a speed somewhere between the two.

    I don't know if that multiple extrapolation ends up being much better than a blind guess, but at least it's something.

    I just got a bargain minus red filter on ebay and I'll try it as soon as it arrives to see how it works with ortho film, but, from what I've been told, I may as well have bought normal panchromatic film to test with that filter as the effect would be the same.
    Yeah, don't waste your ortho film on testing it---it blocks wavelengths that the ortho film can't see, so it should have no effect to speak of. But it should give you an orthochromatic-looking image on pan film.

    -NT
    Nathan Tenny
    San Diego, CA, USA

    The lady of the house has to be a pretty swell sort of person to put up with the annoyance of a photographer.
    -The Little Technical Library, _Developing, Printing, And Enlarging_

  8. #78

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    Do not use a red filter with orthochromatic film unless you want unexposed negatives.
    A red filter will only allow "red" light to reach your orthochromatic film which does NOT see red.
    "Colorblind" film i.e. unsensitized silver emulsions are only sensitive to UV and far blue light, the addition of the orthochromatic sensitizing dyes allows the film to see UV, Blue and Green light all of which a red filter will block.
    If you want to shoot by natural light and have your orthochromatic (or panochromatic film respond to the same spectrum that the "colorblind" film see, you need to only let those colors through, UV and Blue light is what you are after, so use a dark Blue (that Wratten #47B for example). If shooting indoors or under artificial light, just use a Blue light source.

  9. #79

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    Quote Originally Posted by t-royce View Post
    Do not use a red filter with orthochromatic film unless you want unexposed negatives.
    She's talking about a "minus-red" filter, i.e., one that passes everything *except* red.

    -NT
    Nathan Tenny
    San Diego, CA, USA

    The lady of the house has to be a pretty swell sort of person to put up with the annoyance of a photographer.
    -The Little Technical Library, _Developing, Printing, And Enlarging_

  10. #80

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    Quote Originally Posted by Roger Cole View Post

    <snip>

    Anyone else miss Panalure? Any chance of pursuading one of the European paper makers to make something like it again?

    /digression.
    Guess what - Harman/Ilford does. http://www.ilfordphoto.com/products/...Papers+Digital Only available in rolls though.

    Cheers,
    kevs
    testing...

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