Edge density. Is this common problem?

[Michael Clark]

How are these prints made ? Scanner ? Enlarger ?

Film holders and carriers can reflect light onto the film edge. I used to see this when I used Microtek film holders. Now I tape my film to the glass instead: no more edge problems.

Had that happen with my omega's aluminum neg carriers, blacked the inside edges with a marks-a-lot marker which helped.

Mike

[Bruce Watson]

As Bob said, the cure for uneven development, and in particular edge problems, is the Jobo expert drums.

That said, I've seen a little of this from brand new film holders. The film hold down rail can be very shiny, and reflect light hitting it back onto the very edge of the film, such that the edge gets both direct light and light reflected off the hold down rail resulting in increased exposure. It typically only happens on the negative where it's getting lots of light anyway (like skies). The cure for this is a little fine grained sandpaper to take the surface of the hold down rail from shiny to matte.

[Mark Woods]

I was having the same problem, but only with 8x10. One of the members here suggested pre-soaking the film for 4 minutes. I did, and that solved the problem.

[Merg Ross]

I was having the same problem, but only with 8x10. One of the members here suggested pre-soaking the film for 4 minutes. I did, and that solved the problem.

Yes, my original thought to this problem was development procedure. What size film, what size tray, and do you pre-soak? The latter is essential. With the proper procedure, tray development should yield negatives devoid of this edge problem. Perhaps there are other factors that come into play here, but I have never had this problem with tray development. I did have such a problem with hangers and gave them up decades ago.

[jvuokko]

Back to old topic

I think that I am never fully satisfied with the evenness of the skies. Perhaps I am just chasing a ghosts?

Here's example. Fomapan 100. 4x5, developed in jobo expert 3010 using D-76 1+1.
Rotation was done on rollers by rotating tank manually as I don't have jobo processor and my motorised rotator doesn't work well under heavy 3010.


There's still a bit unevenness on the sky. However this is best result with 3010 so far.

[Jac@stafford.net]

The top of the film (as it would be in-camera) has little of the effect. I agree with others who suggest you check the camera for edge reflections.

[paulr]

What developer are you using? Some developers demand much more even flow to give even development. Generally a formula that encourages edge effects will be more challenging.

I used to use D-76 in a jobo (non-expert) drum, and always had a strip of increased density on the top and bottom edges. I eliminated the problem by reformulating my developer. Switching to the expert drums probably would have worked also.

[Jerry Bodine]

Had that happen with my omega's aluminum neg carriers, blacked the inside edges with a marks-a-lot marker which helped.

As soon as I bought my Omega enlarger, I took all my carriers (6x6, 4x5, 5x7) to a professional "plater" and had them anodized to make them flat black all over for durability. Expensive, yeah!!

[David Vickery]

The Tray is too small and you may also need more random agitation.

[Doremus Scudder]

There are a couple of different topics being discussed here that we should differentiate.

The first is increased density on the negative due to reflections from the filmholder edges or hold-down rails. I've had this happen and it's maddening. Sanding with fine sandpaper and a little flat-black spray paint usually solves the problem. However, I don't believe this is the OPs problem.

Another is a similar problem: that of reflections from negative holders when enlarging or scanning. The solution is similar to the above: identify and modify the reflective surface.

The third, and what I believe to be the OPs problem from looking at the examples posted, is increased density on the edges of the negative from developing. When tray developing, this is usually due to using too small of trays and/or pushing the film down into the developer to quickly, causing turbulence at the edges which gives the increased density. The solution to this is to refine your tray-developing technique. Use a tray one size larger than the film you are developing, use a pre-soak (I like a minimum of three minutes) and, most importantly, take real care when immersing and shuffling your negatives to not push them straight down into the developer quickly. Just plopping it down flat and then pushing down with the balls of your fingers will almost inevitably lead to increased edge density. I slide the negative in, letting one side lead just a bit, and gently guide it to the bottom of the tray. The negative should almost sink on its own. Anything you do that increases the flow of developer at the edges will have an adverse effect on evenness. Try to keep the developer flow even across the whole negative surface. This should help with the problem.

Hope this helps,

Doremus