Unknown Artifacts on Rollei 4x5 Sheet Infrared 400 Film

[Matt Hall]

I exposed some of this Rollei 4x5 B&W Infrared 400 film through my astrograph camera. I shot the Orion Nebula and surrounding H-alpha regions. It was a tracked exposure, 30 minutes @ f/2.5 and I used a Wratten #25 red filter to record approx 600nm and above on the film. I had my lab process in D-76 at 22C for 12.5 min. - a 2 to 2 1/2 stop push process (equivalent ASA 400-600). Surprisingly the negatives came back extremely thin. I can see the main stars in Orion, and obviously Sirius, but no nebulosity anywhere.

HOWEVER, I do see two very strange blobs (see attached image). First off, my film holders are IR certified. You will notice that the stars are pinpoints in the image, so these artifacts are not just out of focus point sources--my camera was properly focused. I took the film to the lab in a factory triple box with the film wrapped in an aluminum pouch inside (just like it comes from the factory). I also made sure the lab turned off ALL their safe lights (including any IR lights) before opening my film box for processing. After reviewing the results with the owner of the lab we concluded the following:

1. There are NO notches on the film (there is actually a sticker on the front of the box that states there are no notches and that the film is loaded emulsion side UP). The warning sticker is in both English and German indicating this was done at the point of manufacture in Europe, Belgium to be exact. To us the no notches means that this film was likely cut from larger stock. That opens up a whole other can of worms (what was the condition of the original stock?).

2. If you look closely you can see what appears to be the number '5' in the smaller artifact. There is nothing in my film box or film holder that would have imprinted this figure.

3. We both feel that this film was exposed to some light source (be it visual or IR does not matter) prior to being cut into 4x5 sheets.

I have more film I exposed on that same night to still be processed, I just sent in this one as a development test. I cannot turn those into the lab as tomorrow is the Thanksgiving holiday and the lab is closed on Friday. So Monday it is. If anyone has any thoughts or experiences with this I would appreciate hearing from you. I spent almost $100 on this box of film and am concerned that it is complete junk.

 

[BobUK]

Could they be flashes from the navigation lights of a passing aeroplane?

 

[Andrew O'Neill]

I'm surprised that the film had no notch codes. I use this same film and have been for years. There has always been notch codes. Does the box it came in say Rollei on it?

 

[Matt Hall]

No, I had several planes fly through the scene during the exposure and they don't even show up. Sirius is the brightest star in the sky and it is just a speck on the film. To create something as intense as this exposure was would have required flashing a light almost directly into the lens. Also, why the number '5' in the middle of the one artifact? I think the original film stock was kept in a box or something prior to being cut that was not light safe. It had some numbers in the outside which transferred to the film when the light leaked through.

 

[Matt Hall]

The box looks authentic to me. Here is the box and a close-up of the sticker.

 

[koraks]

I used a Wratten #25 red filter to record approx 600nm and above on the film. I had my lab process in D-76 at 22C for 12.5 min. - a 2 to 2 1/2 stop push process (equivalent ASA 400-600)

You're pushing the film way beyond what is reasonable. Expose more. Lots more. The red filter easily cuts out 2 stops or so and no matter what the term 'push processing' makes you believe, extending development doesn't make your film faster.

If you look closely you can see what appears to be the number '5' in the smaller artifact.

Might be just a random shape really. I can see the '5' in there, but no guarantees whatsoever that it's really a number.

We both feel that this film was exposed to some light source (be it visual or IR does not matter) prior to being cut into 4x5 sheets.

That would almost always result in vastly larger artifacts and overall fogging. This seems pretty concentrated & focused. It's not the kind of accident that allows itself to be explained very easily by accidental exposure during confectioning/finishing.

I spent almost $100 on this box of film and am concerned that it is complete junk.

Process a sheet without exposing it first; if it comes out clean, you know at least that sheet was not accidentally pre-exposed.

I don't know for sure what caused this defect you're seeing. Then again, I don't know how the image was framed and what kind of optics involved, and if those might have been the plausible cause of the captured pattern.

Can you show a photo of that sheet of film held against the light? The way it's photographed right now very clearly shows the phenomenon, but it's a little hard to tell what's going on without a real world reference that tells something about density etc.

PS: I'd recommend processing your own film. Nothing wrong with using a lab, but you can save serious money and get a much quicker turnaround esp. if you're shooting sheet film.

 

[Andrew O'Neill]

I have several boxes that look identical to yours, but none have that sticker... How the heck are you supposed to when it's emulsion side up when you load them into the holder??

 

[Matt Hall]

Maybe that is the problem. The film was loaded emulsion side down and the light through the base caused some scattering effect?

 

[Matt Hall]

First of all, let me correct a statement from my previous post. After calling the lab to confirm the processing details I discovered that they process at 20C not the 22C as I stated. I also confirmed that they use D-76 developer at the stock dilution. As for processing myself, I used to do that, but my lab charges me $4.00/sheet and I get it back the same day. Can't do much better than that.

In response to "koraks" post the Rollei spec sheet on their website for this film states that the development time for this film using D-76 at 20C is 10min. 50 sec., so I do not feel that the 12 min. 30 sec. we used was way beyond what is reasonable. As for "push processing" not making the film speed any faster, Rollei itself rates this film at ASA 400 for a push development time. Normal processing time for this is around 6 min. @ ASA 100 but they call for the extended "push" time in order to reach the 400 speed threshold.

I have attached more photos as requested. I did notice one thing in particular. A 4x5 film holder has a rail on either side that holds the film down flat. This also happens at the top and bottom of the sheet. This results in a narrow section of the film on the edges that gets no exposure, it has no density and is clear. Notice how this negative records density ALL the way to the edge of the film. That would suggest that the film was exposed or fogged prior to being loaded into the film holder. Especially seen in the large partial artifact. It goes all the way to the edge of the film. That would not have been the case had this happened after being loaded.

 

[Matt Hall]

Also, as far as the equipment I am using and the optics, I have attached a few photos to illustrate. I have custom built a 4x5 film astrograph camera using a Kodak Aero Ektar 305mm f/2.5 lens. I have exposed many sheets of color negative and transparency film and never seen this happen before. It only started when I tried shooting with this new B&W IR stock.

 

[OAPOli]

I don't know what would have caused the artefacts. But it looks like the sheet is underexposed. A few ideas:

1) Rollei 400 is Agfa Aviphot 200, an aerial film with its own requirements for contrast. For pictorial purposes, it is best exposed at ISO 100.

2) A Wratten #25 generally needs a 3 stop compensation.

Now, astrophotography is different from normal photography. Not sure what the light spectrum looks like, and there isn't really shadow detail, just more faint stuff.

But with the filter, an ISO of 12 would be a good start. I checked the Rollei datasheet and the reciprocity compensation is severe at ~3 stops for a measured exposure time of 30s. So I think you need way more exposure time. Maybe you can experiment with a 135 or 120 camera?

 

[koraks]

sec. we used was way beyond what is reasonable. As for "push processing" not making the film speed any faster, Rollei itself rates this film at ASA 40

Whoch is likely optimistic under normal daylight conditions, and you used a red filter. What was the exposure time?

So far there's no sign of image-wise/intended exposure, so something's very wrong somewhere in the process. Either way, exposing at 400 through a red filter is a recipe for gross underexposure and possibly no image whatsoever. It doesn't matter how it's developed. Overdevelopment does not compensate for gross underexposure.

Sorry, I can't tell what the cause of the fog is; I'd process a sheet straight out of the box, see if it comes out clean. Do you only have this one affected sheet so far, or are there more? How many sheets have you tried in total and what do they show?

 

[Craig]

To me that's a really odd pattern of exposure, it doesn't look like a typical light leak with the concentric rings of exposure. A wild guess, but it almost look more like exposure caused by a radioactive substance?

 

[Matt Hall]

Some of you seem to be missing the point of this exercise. I have attempted to build a completely new camera using an older aerial lens. I am not trying to get the perfect portrait of the night sky but just see if I can get this beast to work again. I have been shooting the night sky for 40 years and have plenty of gorgeous images to hang on my wall to go along with my degree in scientific/industrial photography form Brooks Institute. I just thought it would be incredibly fun to get some 4x5 images of the cosmos. So switching to a different format is out of the question. Either I can get this thing to work or not.

As for the new B&W IR sheet, I realize that you are not looking at the original but merely a small scan. I can clearly see the constellation of Orion in the negative, and probably 100 or more other stars using a magnifier. So there is exposure there, albeit it very minimal. I just found out the other day that this is really film that should be rated between 50-100, even though Rollei markets it as 400 speed film. I had no idea that they meant you had to push process it to get there. Obviously my goal of reaching 1600 speed with a two stop push is history. This is the very first time I have ever used this film so this entire process is a test! Of course it will be under exposed. That is how you eventually arrive at the correct exposure/development combination.

As for the exposure time, I have all that listed in my original post at the top. Now, for the MOST interesting comment from anyone so far . . . .

Radiation! WOW, that is incredibly insightful. Most of you are likely not aware that the rear element of this lens contains thorium, a radioactive element with a long half-life. It was used by Kodak to achieve critical performance for optimal light transmission and dispersion. It has a relatively low radiation level that disappears into the background at just a few feet distance, but perhaps it could be a part of the problem. But . . . wouldn't it result in a more uniform density rather than these distinct spots? It emits mainly low level alpha particles which I'm not entirely sure could be the culprit, but DEFINITELY worth looking into.

As an aside, this thorium turns the glass distinctly brown as it decays, causing up to a 2 stop light loss and a discoloration of the image. I had to overcome an incredible hurdle even to get this to take photos. I spent a few years researching it before stumbling upon an article explaining how somebody had discovered that their 35mm lens (which was turning brown) had been left in a window sill and had cleared up when exposed to the sunlight. UV light was the answer! I found a low wattage UV LED light (so not to introduce any heat) and put it in a stand in my shop. It took 7 weeks going 24/7 but it finally cleared! See below.

B&W IR film in a 4x5 format may end up being a dead end, but at least I tried it before giving up. One of my instructors at Brooks told me this a long time ago and I have never forgotten it. "It's not the result that counts, it's the journey getting there that matters." I'll keep plugging along.

 

[OAPOli]

@Matt Hall I was suggesting experimenting with smaller formats as a less expensive way to dial in the exposure time. But I get that you're not looking for advice on that.

Film is not very sensitive to ionizing radiation. Even If it was, you would had seen its effect on the previous long exposure photos.

 

[BobUK]

I have several boxes that look identical to yours, but none have that sticker... How the heck are you supposed to when it's emulsion side up when you load them into the holder??

Place the film corner lightly between slightly moist lips. When you open your lips the emulsion side sticks to one of the lips. Try it on an undeveloped leader of a roll of 35mm.
I used to do this when Cibachrome printing in complete darkness.