Swapping film half way

[apdz]

Hey got an urgent question... hope this is the correct place to post.

I'm half way through a roll of film at asa400. I need to use asa800. Can I rewind the film half way and put in a new one at asa800, then to return to the asa400 film can I load it up and shoot with the cap on until I'm back to where I was? Shooting with the cap on should leave the photos I've taken untouched, right?

Seems like common sense but I'd just like to check with more experienced users - or are there any other methods (I'm using an m6) Thanks!

 

[awbphotog]

I've done this countless times, with varying results. Most of the time if it's the same camera, I can pretty well get back to the original spot on the roll, but make sure to write what exposure you're on on the outside of the roll. Leaving the cap on will most likely ensure that your exposures remain untouched, but just to be sure put your camera to the highest shutter speed/smallest aperture (highest f stop i.e. 22) combination to minimalize the chance of fudging your exposures. You may lose the one frame you left on due to overlap, but that's a small price to pay for being able to switch films mid-roll.

Also...make sure you don't wind the roll completely into itself. There are methods to get your rolled up film out of the canister, but in my experience it's rather frustrating and should be avoided if at all possible.

Good luck!

 

[mdarnton]

I used to do this all of the time, and was shooting slide film, so I got in the habit of winding the shutter, flipping the sprocket until it clicked in, and then always loading the film so that the first hole on the upper edge of the film is on the first sprocket tooth. That way, if your cameras are the same model, you can put the film back right in the same place, and not overlap or skip, and not end up with half a roll of slides mounted chopped down the center. I still do this, out of habit, but rarely change films in midstream anymore.

 

[Richard G]

This has worked best for me on the M2 and the Hexar. With the M2 I write the number of the frame on the canister, being the number of the frame just shot and the camera not wound on to the next shot. That number also depends on how many I wind on at the start of a roll, which is always standard, turning the counter to 1 for the first shot I am about to take. When I reuse the roll I trim a bit less than a centimeter from the leader and reload and cock the shutter to the next number on the frame counter than was written on the roll. This sees me lose less than a frame. Silly I know, but when I first started I was spending my father's money and I felt obliged to be as frugal as he was. And he gave me the camera.

The Hexar is even easier and when it doesn't matter so much I have reused a roll and lost barely a sliver as you can just lay the film leader a little beyond the mark when loading.

I know I have some tight fitting lens caps but they aren't all like that, so I prefer a body cap and pressing the camera against my thigh, set to maximum shutter speed, with my back to the sun if possible, to shoot the blanks. I always have a body cap in the bag.

 

[Papercut]

I do this rather frequently. As long as you don't fully rewind the partially used film, note the number of exposures, and shoot through the exposed frames when you re-load it with cap on and smallest aperture and fastest shutter speed, it should work fine.

I never bother trying to load the partially used roll so that the frame spacing is exact simply because I burn an extra frame (blank) to make sure there's no unintended double-exposures. One wasted blank frame won't break the bank and it's a good reminder when the film is developed that I did a film swap at that point.

 

[apdz]

Hey thanks everyone, this is just the info I was after! and good point papercut about leaving a reminder. Hopefully this should work out ok!

 

[Paul Luscher]

Trick I learned from Pop Photo years ago was this:

Wind the film back, leave the leader out. On the end of the leader (on both sides) I write the number of the last frame i shot, with a Sharpie.

When I put the roll back in a camera I wind the film on (lens cap on) to TWO FRAMES past the last frame shot. This prevents any possible double exposure on the last frame shot, even though you might lose a frame of two.

 

[kossi008]

When I put the roll back in a camera I wind the film on (lens cap on) to TWO FRAMES past the last frame shot. This prevents any possible double exposure on the last frame shot, even though you might lose a frame of two.

+1 on that, as it works also on cameras with not so reproducible film placing.

 

[River Dog]

I have done it too, into a different camera and exposed with the lens cap (on manual), three frames past the original frame count. Lost maybe four frames in the exercise but on a 36 I got back a couple at the end.

 

[sirimiri]

If you're talking about C-41 or B&W film, have you considered just setting your meter at 640 and "rolling with it"?

I feel that splitting the stop is pretty easy for modern films to handle, as long as your subject matter doesn't involve the utmost in contrast.

Of course if you need a wholly differnet emulsion, then you have little choice.

With the exception of a Bessa I used to own, all of my 135 camera bodies wound with a precision that made them easy to reload partially-shot film. sometimes you loose a couple of sprocket holes worth of film but you can easily avoid the overlap by the methods others indicate above.

*But* if the film will be machine cut or you haven't cautioned the lab, do so when you drop it off. That way they know to look for frame spacing oddities when they cut you roll into strips.

 

[rbsinto]

I was taught how to do this over thirty years ago and have been doing it ever since.
The techniques described here by others pretty well sum up how its done. However, there is one one more important point that should be made.
With slide film that has been loaded and re-loaded more than once, I always make a point of advising the lab to manually inspect the slides when cutting them for mounting. Otherwise a change in spacing of the frames beyond the point where I began shooting after re-loading may mean I get back slides consisting of halves of two different shots.
I only made that mistake once.