Rollei Ortho plus 25 - reciprocity

[Vangelis]

Hello.

I can not find any data about the reciprocity of this film.

Because it is low ISO, i think they are necessary for low light conditions.
I consider to give it a test for reciprocity with a roll of 135 before try the 4x5"
Another option is to contact Rollei directly?

Any opinions and experiences are welcome!

[Jim Noel]

Hello.

I can not find any data about the reciprocity of this film.

Because it is low ISO, i think they are necessary for low light conditions.
I consider to give it a test for reciprocity with a roll of 135 before try the 4x5"
Another option is to contact Rollei directly?

Any opinions and experiences are welcome!

reciprocity with ortho films is heavily dependent on the %age of red in the spectrum of the light being used. If you are thinking of using incandescent light sources for your "low light" exposures, your exposures will be extremely long, even into hours, if the film will expose at all. Check the spectrum with a prism or CD.

[Vangelis]

The use of prism or CD sounds a good idea!Thanks!

The film i want to use it in the field.
Mostly for landscapes and architecture.
Sometimes in deep shadows or a little while after sunset, i think that the exposure will need correction for reciprocity.
This is my question, to how much correction needs.

[paulbarden]

Vangelis, I have searched and found no information whatsoever about reciprocity characteristics of this film. It seems most users have adopted reciprocity correction rates for slow Rollei films like RPX 25 and finding that is close enough.

[Vangelis]

Thanks paulbarden,

I will try a roll first, with the correction suggested by Rollei in the RPX 25 datasheet.

I will post my results soon!