Line artifact on 4x5 negatives

[ellisson]

I'm getting a line down the side of every 4x5 negative I've processed. Its about 1 inch from the side, about 1/32 thick, and perfectly straight.

Could this be a defective batch of film (Ilford Delta 100) - I'm still on the same box. Could it be a film holder issue? Whatever it is, its consistent! Any ideas?

 

[zone v]

Are you completely removing the darkslide from the film holder before exposing? Sounds like a sharp line from the edge of the darkslide.

 

[ellisson]

Artifact on 4x5 negatives

It seems like it should be something with the film holder, but I completely remove the dark slide before each exposure, and the holders are clean.

 

[cazenll]

Try developing a piece of film right out of the box. Going one step further sacrifice a piece of film and see if an unprocessed piece has the scratch. If it doesn't put it in the film holder and go thorugh the process of exposing. Check for the scratch each step of the way.

Louis

 

[JBrunner]

Is it a scratch, or exposed in the neg? If it is a scratch you will probably be able to feel it on the neg. Is it dark or light? A single line or a many fine lines close together?

 

[ellisson]

Its a single light line on the negative, and perfectly straight, same location. I'll see if Louis's step by step procedure can solve this mystery.

 

[Mick Fagan]

Is there a difference between a portrait neg and/or a landscape orientated neg?

It could be a sagging bellows catching light on one of the internal ribs. I have had this happen when I used a fair amount of front rise, took me a while to find the culprit.

Mick.

 

[Bob F.]

Is it happening with different film holders? Is it light or dark on the film?

If it is not a scratch then a scan would be useful for diagnosis purposes.

I find that of the multitude of problems I have had, only one was due to a manufacturing defect (not Ilford, for the record). I find my capacity for error exceeds that of most manufacturers by several orders of magnitude!

Good luck, Bob.

 

[ellisson]

It is happening with different film holders, and the line is lighter than the surrounding areas on the negative. All exposures were of landscapes (but I haven't taken any portraits views yet), and with 1-2 cm of front rise. The bellows has been extended almost to the max for several of the images (for 300 mm lens) and about 150mm for the remaining ones, so I haven't seen significant sagging.

Agree with Bob that problem is likely something I'm doing or not doing. I get back to the darkroom Wednesday night and will try developing a sheet of film directly from the box to prove its not Ilford's problem. Thanks to all - I will report back with the findings!

 

[Simon R Galley]

Dear Ellison,

If you do not find out what it is send a sheet back to us, complete with the batch number etc, it does help a bit if you have an electron scanning microscope to examine any defect,I have checked any QC's on Sheet film and we have none outstanding on any DELTA historical batch. The strange thing is that they all have it, if it was a coating line 99.98% it would have been found and cut out completely, and if it did get through QC the sheets are cut across the web so you would be extemely unlucky to have one ( line ) in a box never mind all of them marked. So its a strange one, I will keep my eye on the thread.

Regards

Simon ILFORD Photo / HARMAN technology Limited :

 

[ellisson]

Sorry for the delay. Surprisingly, the line artifact is present before exposure. I briefly exposed a sheet to room light, right out of the box, and processed immediately: no film holder or other manipulation, See the attached image. Simon, I'll send an unexposed sheet back to you with batch number.
Gary