Discontinued: ORTHO 25
ADOX ORTHO 25
Orthochromatic film with 25 ASA
Orthochromatic films are extremely sharp and high resolving but blind for anything red.
They can be developed in any soft working developer like Technidol, Neofin Doku, LP Docufine or diluted universal or paper-developers.
The softer the developer the more greyscales are reproduced. In normal equalizing developers the film works slightly harder and needs to be printed on soft graded paper.
ORTHO Films feature a unique view of the scenery. Usually the sky comes darker and red objects lighter in the negative compared to panchromatically sensitized film.
In the final print the red objects then are darker and the blue objects lighter.
Interesting images can be achieved in portrait and landscape photography.
Lips will be darker but also spots are pronounced.
In ancient times all films were orthochromatically sensitized (due to the lack of further going sensitizers) so you can reproduce the look of 1890ies images with this film.
However many portrait photographers back then instructed their clients to use blue lipstick and touch up in order to counterbalance the effect.
The film can capture up to 330 L / mm in high contrast and up to 250 L / mm when developed to full greyscales.
It is coated onto a clear PET base and has an anti halation and anti curling coating on the backside.
It is fully archival stable.
Ortochromatic films are superior in sharpness and resolution because the silver haloides do not need to be sensitized to red.
The 35mm film can be reversal processed to a slide because of its clear base.
Spectral response: 380 until 610 nm
Resolution up to: 330 L/mm
In terms of speed and resolution it can be used as a replacement for TechPan, however TechPan and ADOX CMS are orthopanchromatic films with a different “view” (spectral response).
The film can be used for making internegatives or slide dupes from a negative, preferably as a direct contact.
If you expose the film under the enlarger use a black cardboard underneath to prevent halation !
Development can take place under a dark red filter by inspection. This also makes it very suitable for pinhole photography where you hardly ever know how the exposure came out to be.
Available as 35mm, 120 and Sheetfilm.
The emulsions differ slightly between 35mm and the sheetfilms. Development times are not always 100% identical.
We recomend development by inspection.
Development starting times ORTHO 25 (35mm film):
Rollei RLC developer: 8-9 Minutes
ADOX APH09 1+40: 4-6 Minutes
ADOX ATM49 Stock solution: 6 Minutes
Rodinal 1+50: 4-6 Minutes
D76 Stock solution: 5-6 Minutes
Xtol Stock solution: 5-6 Minutes