Orwo NP55 - sensivity

[thevenin]

Hello!

What is the nominal sensitivity of the NP55 film?
(It's a 35mm B&W, cinematographic film manufactured by Orwo)

Adam.

 

[AgX]

Welcome to Apug Adam.

Concerning your question: I could not find any data in my archive. However a reasoned guess would be that 55 would be sensitivity in GOST (later films had the DIN-sinsitivity in their name). Thus about 18DIN.

 

[thevenin]

Hello,

Thank you for reply,

Yes, I know that rule, but ufortunately it doesn't work with NP55. Why did they use soviet units instead of german?

I'll try to expose the first roll at 25 and 50 ASA.

Thanks again,
Adam.

 

[argus]

Unfortunately, NP55 is not listed on the Filmotec website:
http://www.filmotec.de/Produkte/produkte.html

Maybe you could ask them?

G

 

[AgX]

Why the guess with soviet units? Because the Filmfabrik Wolfen was a soviet company from 1945 until 1953.

Actually I thought the NP55 was a quite old film, but meanwhile I learned that it was intended as film for shooting TV features...

 

[MartinB]

maybe 22DIN

I have never used the film but a Google search turned up a
Czech post suggesting 22DIN/125 ASA. I used Google translator since I can't read Czech.
Hope this helps.

Czech ref to Orwo NP 55

 

[Kino]

Just WRITE the guys at ORWO; they are very nice and will probably have the answer for you in a day or so!

http://www.filmotec.de/English_Site/Contact/contact.html

You'll want to write to Mr. Frank Böhme, the Marketing Manager.

 

[thevenin]

Thanks guys!

I have never used the film but a Google search turned up a
Czech post suggesting 22DIN/125 ASA. I used Google translator since I can't read Czech.
QUOTE]

Martin, I've already seen this Czech (and Polish) sites. The results are weird: 50ASA to 125ASA, so I decided to write this topic.

I'm going to shoot a test roll (we have approx. 2x120 meters of it) to determine actual sensitivity (and foging) of this film. I'll write here about my results.

Adam

 

[MartinB]

Adam,

Looking forward to the results, it sounds like you have enough film for some experiments.

Since you are new to APUG, you may not have seen previous posts on testing film. You should search through the posts in the B&W forum and you should find all kinds of good information. The stand/minimal agitation technique with dilute 1:100 Rodinal can be useful when you are not sure about exposure.

The 50-125 ASA/ISO you have found on the Czech and Polish sites are within the normal range found with most film. For example, you will find APUG users who expose Ilford FP4+ (nominally 125 ISO) anywhere from 64-250 ISO and adjust their developer and processing time to suit. I expect you will find useful exposures with the ORWO anywhere from 50-125. Probably the 50 ISO will require a little underdevelopment and slightly lower contrast whereas the 125 requires more development (longer) and results in slightly higher contrast. The Czech site seemed to have some suggestions for a starting dilution/time for Rodinal. (I would suggest the 1:50 dilution as I have found 1:25 for other films requires more precision in nailing the time and agitation)

Also the massive development chart at Orwo on Digital Truth has info on some Orwo films (NP22 but not NP55) that may be helpful. (This link is buried in the notes section of the chart, not off the main pick list)

by the way, welcome to APUG, from western Canada!

Martin

 

[thevenin]

Martin, thanks for reply.

Yes, I'm new to Apug, but I'm not novice to B&W processing ;-). Here, I'm interested only in NOMINAL sensitivity
(manufacturer's data, I don't even ask about e.g. characteristic curves...) Of course ACTUAL sens. will be different. Fortunately metal cans were frozen and originally sealed but stickers with information are completly unreadable. The estimation of "optimal" processing parameters will be necessary, I agree. I'll start with 0.5m specimens next week.
Adam.