Maco Genius film - red light safe ortho or not?

[Akki14]

Bought a box of 4x5 Maco Genius lith film and it says orthochromatic in the data sheet but I'm not sure if it's like APHS where I can develop by inspection under red safe light or not. Has anyone developed by inspection with this?

 

[dancqu]

Bought a box of 4x5 Maco Genius lith film and it says
orthochromatic in the data sheet but I'm not sure if it's
like APHS where I can develop by inspection under red
safe light or not.

Orthochromatic films or papers are sensitive to blue
and green light. IF that which is in the box is truly ortho
then a red light is needed.

I say If because I've encountered papers, Slavich
and Emaks Graded, where red is specified but the papers
are actualy blue only sensitive. Also, years ago I was employed
in part as the processor of lith films. I worked under a rather
high level of yellow to orange light. Dot sizes had to be
evaluated and film 'snatched' at just the right time.

My suggestion; turn up the lights, make it easy to see.
See what happens. Some darkroom workers unnecessarily
handy cap themselfs. Dan

 

[snallan]

Hi Heather,

I have been working with this film to produce copy negs by reversal, and treat it like sensitive paper. I use two Duka 50 safelights with the red filters fitted; and at a fifth of their maximum intensity, they test safe for the Maco Genius in excess of twelve minutes.

On the dry side the safelight is partially direct, and about three feet from the working surface. At the wet bench the safelight is only about a foot from the developer tray, but is directed away from the tray and up a light coloured wall for indirect light.

I don't develop by inspection, but I feel this would be perfectly feasible with this film, and red safelights, as long as they are not too bright. For example; a safelight test with my dry side safelight at maximum output caused fogging of the Maco Genius at four minutes.

I had tried working with the white diffusers on the safelights, which gives a yellow/orange light (the lamps are sodium vapour), but had fogging even with short exposures at low intensity.

 

[Akki14]

I don't own an amber safelight, I only have red safelights and I have developed by inspection with APHS ortho litho film, I was just asking for experience with Maco's ortho litho film specifically.

 

[Akki14]

Duh I've just read the box, it says red safelight no light-brown or green. So it's probably similar to APHS and I'll just do what I have been doing with cut down APHS.