Please help identify strange marks on processed sheet film

[Stephen Thomason]

I've experimented with a Yankee developing tank and have very strange marks on the developed film. I have read the posts about the difficulty achieving uniform development, so I adopted the slide movements as prescribed by the manufacturer plus a couple of washing machine type twists. Six sheets were developed with sheets placed in every other groove so as to allow plenty of room for the chemicals to slosh around (reasonably gently).

All of the negatives have the marks shown below. (replenished XTOL developer, by the way). EXCEPT for the sheet that I earlier processed in Rodinal at 1+100 using 60 minute stand with one lift and replace at 30 minutes. It came out just fine. There was no agitation, just the lift and replace.

Before committing six sheets, I DID process another sheet all by itself, using the same techniques to be used with the six sheets, and did not notice at that time anything unusual. HOWEVER, after the six sheet affair, I examined the solitary sheet more closely, and it DOES have those same marks, but they are only barely visible, as compared to the glaring presence of the six sheet batch. I don't think they will be an issue in printing due to the subject matter, but I do not want to continue with the Yankee tank unless I can avoid those marks.

I don't believe it is reticulation since the solutions were at the same temperature, and I have never seen this pattern of reticulation.

The film is a mixture of Ilford conventional emulsion and delta emulsion (Delta 100 and HP5+). Times were Ilford times adjusted for replenished XTOL and intermittent agitation.

Thinking that it might be the agitation, I developed 9 sheets in my JOBO rotary tube that has the two 12 sheet reels. Again loading the film in every other groove. The same mixture of film does NOT those marks that the film processed in the Yankee tank have. The negatives look normal. Development time was adjusted for rotary processing, still considering replenished XTOL adjustment.

The marks are on the NON-emulsion side. All the film was sprayed with Ilford rinse aid in the same manner, coming from both the Yankee tank and the JOBO tube. The marks almost look like scratches, but are not visible unless you get the angle of the light just right.

Although only a portion of the film is shown in the picture, the entire negative has those marks. They are all in the same direction (the direction of the agitation, lengthwise) but they are not completely straight nor do they necessarily continue from end to end - some start, disappear for a little space, and then start again. It almost looks like grit was sloshing back and forth, but since the emulsion side is softer, why are the marks/scratches/wavy lines on the base side?? The film was loaded with the emulsion side curved convexly. (Been a while since Fluid Mechanics, but theoretically I suppose the fluid could have different velocities across the film surface, making it even more puzzling why the non-emulsion side carries the marks).

The marks are easily shown in the upper left of the pic. Anybody got any ideas what caused this and how to prevent it, other than, of course, use the Yankee for stand development only, which seems like a jolly good idea!

[koraks]

Nit sure what the cause is, but they do look like scratches to me. I don't think it has much to do with fluid dynamics; this seems more like the sheets were rubbed along a coarse surface or ridge, perhaps when taking the film pit of the tank or during later processing.

[IanG]

Definitely scratches, check your dark-slides carefully.

Ian

[Stephen Thomason]

koraks: I also thought initially that they were scratches, but they are wavy, not straight. The way the Yankee tank is constructed, the sheets were removed carefully after processing in daylight so I am confident they didn't get scratched while unloading. The guide was used loading the sheets, but there are openings where the film would not touch the edges of the guide while the film is being loaded, but nonetheless contain the same marks.

IanG: I also thought the marks could come from the darkslides, but because the sheets processed in the JOBO didn't have the marks and came from essentially the same brand and condition of film holder, I eliminated the film holders/dark slides from consideration.

[koraks]

Maybe do a dry run of your whole process, from loading film in the holders to drying it after development, and carefully observe any opportunity where it can be scratched?

[Doremus Scudder]

Sure looks like scratches to me. If they are, you should be able to feel them with a fingertip or nail, or at least see the damage under high magnification (try a 10x loupe or use a good enlarging magnifier). If they aren't scratches (which you really need to definitively determine) then you may be looking at physical damage such as crimping or stressing of some kind. Keep in mind that many films have an gelatin coating on the "non-emulsion" side. With bending, squeezing or crimping, this can also crack or splinter (just a wild guess here).

Since you've basically isolated the cause to something in connection with your Yankee processor, I'd take koraks' suggestion and sit down with it and a few sheets of scrap film (or trashed negatives) and go through your entire routine looking for where in the process your film can get damaged (or contaminated or...)

It's highly unlikely that the agitation could cause anything like what you have.

Good luck,

Doremus

[alexmuir]

When I'm loading and unloading 4x5 darkslides, which are either Fidelity Elite or Toyo, I get concerned about the film coming into contact with the hinged flap at the bottom. Although it bends back, it has a tendency to contact the back of the film if you don't keep it out of the way. It's just a thought, but contact with that part during loading, or unloading could cause scratches on the film base along the length of the sheet.
Alex

[koraks]

Alex, that thought crossed my mind as well. Particularly towards the end of the sheet this tends to happen, I find. It's also consistent with the scratch pattern shown here...

[Gary Beasley]

Did you use a squeegee of any type on the film? It looks a bit like drying marks from wetting agent trails after squeegeeing. That can be avoided with an alcohol based final dip hung without wiping from the corner. The solution prevents any droplets from forming and making mineral spots. There used to be several commercial products for this job like that, the one I remember was a clear pink liquid though I can't remember the name of it.

[Duolab123]

koraks: I also thought initially that they were scratches, but they are wavy, not straight. The way the Yankee tank is constructed, the sheets were removed carefully after processing in daylight so I am confident they didn't get scratched while unloading. The guide was used loading the sheets, but there are openings where the film would not touch the edges of the guide while the film is being loaded, but nonetheless contain the same marks.

IanG: I also thought the marks could come from the darkslides, but because the sheets processed in the JOBO didn't have the marks and came from essentially the same brand and condition of film holder, I eliminated the film holders/dark slides from consideration.

Sounds like you are pretty certain that using the Jobo reels (are you using the 2509n, 6 sheet capacity reels or an expert tank?) you are not having a problem with Jobo equipment? I would make sure that you are absolutely sure before going much further.

I've never seen marks quite like that from agitation. I sure have scratched the daylights out of film with silly squeegees before I came to my senses.
The comment on going back over step by step makes darn good sense to me. You don't want to blame your tank and have a problem with that one in a million shot later on.
Good luck, Mike