Film holder 'tap'

As I march on with my novice use of a 4x5 camera, I find that the film sheets often don't sit evenly within the film holder. What is the cure? A sharp rap or tap on the top or bottom of the film holder or does the problem originate with the film loading stage?

Thanks!

I had this problem for a while. Before exposure you can knock the film too where you want it. But I eventually just bought all holders that have a lip on the bottom flap that does not allow the film to move down. That solved all my issues.

The classic sheet film holder tap is supposed to allow dust to fall off the film, though, in my experience electrostatic attraction prevails.

I used to very lightly tap the side of the film holder that is going to be down when the film holder is inserted in the the camera. I don't bother anymore though. Its just not worth troubling oneself over.

BradS said:

I used to very lightly tap the side of the film holder that is going to be down when the film holder is inserted in the the camera. I don't bother anymore though. Its just not worth troubling oneself over.

Click to expand...

It isn't a problem when I enlarge the negative. However, I want the film straight when I make Pt/Pd or cyanotype prints.

Even in that case, the (very minor) imperfection is all part of the beauty of the art work.

I mean, if you're not masking off the print with an over matt then, all the little imperfections show anyway...so, why get uptight about this one? It's part of what makes a hand crafted object valuable and beautiful.

...but, even so, it is easy enough to simply be in the habit of tapping the film holder bottom edge against your hand a couple of times before inserting it into the camera.

Just make sure that when you're loading film, both sides of the sheet are properly seated under the raised lip on either side. I lift each bottom corner slightly when loading to make sure of this. Also make sure the sheet is up into to holder as far as it can go before closing the flap and seating the darkslide. That should help.

Then, when shooting, tap the side/end of the filmholder that will be at the bottom when making an exposure lightly to seat the film before inserting it into the camera back (this means a side if it's a landscape-orientation shot, or the bottom if it's portrait-orientation).

Best,

Doremus

For regular plastic filmholders you can apply an antistatic fluid; it lasts a long time. Film sag is a much bigger issue with 8x10 than 4x5 film, but the only real way to deal with it is via a vacuum or adhesive precision holder. Film slightly shifting around behind the slots in a regular holder has never been a problem for me after decades of shooting; I don't bother to tap.

I have not noticed any problems with my negatives and I don't tap.

Ambrown31 said:

I have not noticed any problems with my negatives and I don't tap.

Click to expand...

There are two reasons I "tap."

First, depending on how I'm transporting and carrying holders, the film can work it's way up a bit, which then allows the code notches to impinge a bit on the image area. Most of the time, this isn't an issue, but I still like to have them squarely in the film rebate, not in the image area.

Second, and more importantly, during long exposures, especially if there is some temperature variation between holder and ambient temperature, the film that has not been seated properly can slide down during the exposure, ruining the exposure (don't ask me how I know...).

So, for me it's tap once with the flap side down to seat the film in that orientation. Then, if I'm shooting in "landscape" orientation, I'll tap again along the long side to make sure the film is all the way to the "bottom" for the shot. It just takes a fraction of a second: " tap-tap-insert-pinch-pull slide" and is good insurance.

Best,

Doremus