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doc
21-Oct-1998, 00:58
Does anyone have experience doing pictorial stuff, landscapes, with ortho film? Ilford rates their film at 80 daylight. If that is so, then that is a density an d contrast I've never seen before, and it's across a wide range of exposures. I wonder if there is some trick-of-the-trade for using ortho for continuous tone w ork. Perhaps there is a brand which is better for pictures which I don't know ab out? Thanks in advance.

Erik Ryberg
21-Oct-1998, 01:58
David,

Take a look at John Schaefer's _The Ansel Adams Guide to Basic Techniques of Photography, Book 2_ 1998 (I think). It has a very good section on using ortho film for continuous tone photography. Basically you need to pre-expose it and then develop the film in very dilute dektol. I haven't tried it but mean to on Freestyle's cheap lith film.

Erik Ryberg

John Lehman
21-Oct-1998, 15:20
I have used several boxes of the Ilford ortho and ortho+ film for landscapes. I rate it at EI 40 and develop it for 12 minutes at 70 degrees in PMK, which gives me the full Zone I-IX scale.

Doremus Scudder
23-Oct-1998, 12:20
Ortho film, being sensitive only to the blue and green portions of the spectrum renders reds as dark and blue and green as significantly lighter when compared w ith panchromatic films. This effect can be duplicated by using a Wratten number 44 Blue-Green filter with pancromatic film giving you the choice to render a sub ject as "Ortho" or "Pan" and at the same time use your usual film and developer combinations. This arrangement works best for me, since I work almost exclusivel y in the field, in that it eliminates the confusion (and wieght) of having yet a nother set of film holders with yet another film. I have even had fairly good su ccess using an 80B color-converting filter to dampen the red response of my panc hromatic films. The effect is similar, though not as pronounced as the no. 44 fi lter. Maybe this will give you the ortho effect you desire with a bit less hassl e. After all, its the final print that counts!

Best regards

Dory

John Lehman
23-Oct-1998, 13:35
Dory's point is true if you are using ortho only because of the lack of red sensitivity. Ortho films in general (and Ilford Ortho + in particular) also have enhanced sensitivity to green compared to panchromatic films (which have a dip in color sensitivity in the green region), and so sometimes work better for scenes where you want to lighten the greens (but not the blues) as well as darken the reds.

For those who think PMK is too fussy, Ilford recommends ID11/D76 undiluted for 8 minutes at 68 deg F for pictorial use

Tony Brent
27-Oct-1998, 22:46
I guess by Ortho film you are referring to the ultra high contrast litho types. I use another ortho film for general picture taking, but will get to that in a m oment.

Yes, you can get very nice continuous tone negatives from lith type films by usi ng a VERY dilute developer. I had good results with HC-110 at 1:64 -- 1:128 and extra gentle agitation. A bonus is that you can develop under 1A red safelight a nd get a good idea of your progress by looking at the image through the film bas e.

This stuff really shines with very flatly lit scenes, like a heavy cloud cover, and not much scene contrast to start with. It brings out small details and textu res.

You have to be careful not to get too vigorous with the agitation.

Lith type films can be had in 8 x 10 for about $65 per hundred sheets, or therea bouts if you shop around.

Now to the other type film. I use Kodak Commercial film in 4 x 5. It is a slow o rtho film but doesnt have as much built in contrast as the lith types, as far as I can determine. It seems to be around ASA 50 -- 80. It was intended for making copy negatives of photographs. I think its still made, but Im not sure. Mine is outdated, but still makes a usable neg.

Hope some of this helps.