Rollei IR film

[DrPablo]

Has anyone used the new Rollei IR film with a Lee 87 filter (or the equivalent)? If so how do you expose the film? I've heard everything from 6 to 11 stops filter factor. And should I be spot metering off of highlights (or likely highlights like foliage), or just use average metering?

 

[kraker]

Has anyone used the new Rollei IR film with a Lee 87 filter (or the equivalent)? If so how do you expose the film? I've heard everything from 6 to 11 stops filter factor. And should I be spot metering off of highlights (or likely highlights like foliage), or just use average metering?

After some googling I came up with "Transmission begins above 730 nanometres." for the Lee 87. I can't comment on that, I have used the Rollei IR with a Hoya R72 filter (720 nm cut-off), and my first findings are that ISO 3 or 6 will do (that's 6-7 stops).

Looking at the spectral sensitivity of Rollei IR 400, there's a steep drop starting at 700 nm, so the 10 nm difference between the filters is certainly not negligible. But how many stops exactly? I wouldn't know. Either wait for someone who has tried, or do your own experiments. This is the best indication I can give you.

 

[Lloyd Chan]

Rollei issued a press release at Photokina 2006 on the Rollei IR400. It says:

"For optimum application as an INFRARED FILM, with ISO 12 or ISO25 both common, most widespread IR filters, the 89B = RG695 = 680-720nm, and the IR filter 88A = RG715 = 720-750nm, are recommended."

 

[DrPablo]

the 89B = RG695 = 680-720nm, and the IR filter 88A = RG715 = 720-750nm, are recommended

Well, I already own an 87. Finding these filters in 4x4 size can be difficult and in some cases very expensive.

I've seen on the web succesful pictures with the 87 and this film. The steep dropoff seems to occur more like between 730 and 750. So I'd think that the 10 nm between the rm72 and the 87 would matter, but not critically.

http://www.rollei.com/files/Rollei IR TA engl.pdf

Is there anyone who has used this combination? I really want to get some recommendations from someone who has done this successfully. This is a very expensive film in 4x5, and I don't want to waste exposures if I can get some guidance.

 

[Fotohuis]

I should take care of using this film over a 720nm filter due to it's characteristics.
I have used Rollei IR-820/400 successfully with the RG715nm filter, iso 12-25.
The sensitivity of this film is going down fast over 750nm so at a certain moment you have no bandwith anymore.

From experience I also know that a red filter will give no 'wood' effect with this film. It just is starting up from 665nm but very weak.
So the Rollei recommendation of 695nm or 715nm seems to be OK.

The advantage of this I.R. film is the easy handling for loading and unloading in subdue light. The film is not really critical and of course available in 35mm, 120 roll film and 4X5".

Best regards,

Robert

 

[msage]

Has anyone used the new Rollei IR film with a Lee 87 filter (or the equivalent)? If so how do you expose the film? I've heard everything from 6 to 11 stops filter factor. And should I be spot metering off of highlights (or likely highlights like foliage), or just use average metering?

I have not had good results with the 87 filter. Little IR effect in my test. I finally ordered the 715 filter hoping that will give me effect I need. I am fast running out of Kodak IR 4x5.
Michael

 

[jproulx]

Slow....

I haven't done "good" testing, but I can say it took three rolls with the 87 filter before I got an image. Sunny day with patchy clouds I was around 2min at f/5.6. Contrast was low in D76 (stock) 68deg 9min (this is for a single 120 roll hand processsed)

It's a place to start.

-Jon