Wratten 88 filter factor

[GraflexNut]

Looking to use do some sunrise infrared photography and general landscape, I have some film and a Wratten 88 filter I found lying around in a display case in my university (obtained with permission of course!). However, I have had trouble finding what filter factor the Wratten 88 filter has. I tried looking through one of the old scans of books about the filters but tbh it was all greek to me. If anyone has any advice that would be greatly appreciated! For reference, I'm shooting Rollei IR in a Mamiya C330 using a Series VI Wratten 88 Filter. Thank you all!

 

[AnselMortensen]

Using a film "similar" to Rollei Infrared (Aviphot), I used an R72 filter at EI of 1.
In. Bright. Sunlight.
Sunrise lighting?
You might want to do a bracketing test under the conditions you want to shoot to determine the proper exposure for your intended use.
Wratten 87/88/88A filters were tested with Kodak Infrared films/plates back in the day.
Rollei isn't particularly forthcoming about the specs of their film...and the IR sensitivity is NOT the same as Kodak's.
Test, and please report back with your findings!