Filing Negative Carrier - Double Edges?

ac123

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I'm filing out a spare negative carrier in order to slightly expand my edges and create a rougher border (intended effect similar to this )

I'm having an issue with this beseler 6x7 carrier where I am seeing this "double edge", occurring both on the projected negative+final print:



I tried filing down the bottom layer so it is slightly bigger than the top layer (the top layer just overhangs on the edges), and for whatever reason it seems to have pushed the "double edge" effect further away:



Has anyone experienced this or might have any advice for achieving a smoother file / removing this edge?
 

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MattKing

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That is normal, and the result of both reflection and refraction.
To eliminate it, use your easel to mask it out.
I actually like the effect:

In this case, from a 35mm carrier in an Omega D6.
 

loccdor

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Nice images! I've gotten similar border effects from DIY masks as well as shiny enlarger negative carriers.
 
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ac123

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A follow-up question here:

Painting the exposed edges black solved my "double edge" reflection issue, though now I'm getting these strange light brown markings around the opening.

Wondering if anyone has any advice on how to further clean up / align the rough edges - in an initial ref I had posted, some of the edges are appearing more teal, not brown - wondering what would make them reflect that way? And what would be the best chance for appearing as solid black ?



I'm aiming for a more "uniform" rough edge look - i.e. more solid edges, not wispy edges, but having trouble achieving

 

Bill Burk

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Also look up and down from the baseboard into the negative carrier and from the negative carrier to the lens.

The bright outline acts like a ringlight and illuminates the space between carrier and lens, so bellows or shiny mount could be an issue. You’ll see it.
 

brbo

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Most likely you will need to make a mask out of thin opaque material that you put on top of the negative. That way you don't get any reflections and the edges will be as hard/regular as you make them. I use a sheet of heavy black paper to make my masks.

 
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ac123

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Thanks for the suggestions.

I did go ahead and bevel the edge, though the print is coming out exactly the same, with the brown dirty edge. maybe I'm beveling in the wrong direction / not large enough of an area ?






Not exactly sure what you mean - when I have the empty carrier projecting blank light, I can definitely see the slight dirty edge around the border that I'm trying to get rid of. However looking up into the lens isn't telling me anything about where it would be coming from - Are you suggesting this could be an enlarger/bellows issue?
 

gorbas

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You need to bevel it much more and wider. You barely took edge off.
In my case I use top Anti Newton glass and glassless bottom, so I leave maybe 0.5mm straight right under the negative and bevel much more than you did and than I should paint it with black. It's never ending process. It can work nicely with Hasselblad negatives but for Rollei TLR negs you need bigger opening. Check with your negatives.
In your case, with both glassless holders I would file it both sides and make it bevel profile look like "hourglass".
 
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Bill Burk

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Yes, take the lens off but put a typical negative in the carrier. Look around inside.
 
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