70mm with mag track, splicing.

[Tom McGarrity]

What’s best, tape or cement ?

[Don Furr]

What’s best, tape or cement ?

I would recommend tape.

[Jim Cassedy]

I often handle/run 70mm magnetic film and all my old projection manuals recommend tape splicing.
Those same manuals also recommend deguaussing the splicer to prevent 'pops' at the splice point.

[Steve Guttag]

What's best? Between perf cement, if done well. Remember the direction the film travels across the heads...you don't the heads (or anything else) trying to peel the spice apart. So, the tail goes on top of the head so the film falls down to the next piece, not step up to it.

If you are scared about your cementing abilities, you can reinforce with tape on the emulsion and carefully reinforce on the base so as to not obstruct the tracks. If you tape over the tracks, you'll get the tell-tale sound drop 1-second before the picture change.

If you want to be different, you can try and find an Imax style zig-zag taper (think pinking shears) and use 8mm tape...it will look a little strange on the top/bottom for those two frames (on Imax, it looks like "dots" on the sides) but the sound drop should be negligible.

[Sam Chavez]

I believe there were 70mm prints released on polyester film so at least those will not work with film cement splicers.

[Steve Guttag]

Sam, do you know of many/any 70mm MAGNETIC prints released on polyester? If it were polyester (and no mag) I would change my stance and switch to ultrasonic splice (for permanent attachment). And, if it is non-mag (and presumably DTS)...no audio drop out, tape or ultrasonic.

[Brad Miller]

If you want to be different, you can try and find an Imax style zig-zag taper (think pinking shears) and use 8mm tape...it will look a little strange on the top/bottom for those two frames (on Imax, it looks like "dots" on the sides) but the sound drop should be negligible.

Oh please do not do this. It looks AWFUL and then the next guy will cut those 2 frames off to prevent his presentation from looking bad. Stick with tape, period. It can be removed with no frames lost. Plus I've seen too many times where people will cut out a cement splice, and then there goes 2 more frames.

[Sam Chavez]

Sam, do you know of many/any 70mm MAGNETIC prints released on polyester? If it were polyester (and no mag) I would change my stance and switch to ultrasonic splice (for permanent attachment). And, if it is non-mag (and presumably DTS)...no audio drop out, tape or ultrasonic.

There may have been one mag polyester print but long ago. Did receive 70mm mag test film with images for sure on polyester though. Still have some around. Had one where they striped and recorded the test reel on the emulsion side and tails up which drove the projectionist crazy.

[Steve Guttag]

Stick with tape, period. It can be removed with no frames lost. Plus I've seen too many times where people will cut out a cement splice, and then there goes 2 more frames.

So, were talking about building a print up on a larger reel/platter? Again, presuming a mag print, this is going to be something that is likely not being built up. I'd take a cement splice still. It is, by far, less obtrusive than a tape splice for both picture and sound.

[Leo Enticknap]

As others have pointed out, there is a higher likelihood that you'll have to sacrifice frames to make it (or that another projectionist will do so to save time and for convenience, even if the cement could be scraped away and the splice remade without losing any), which, given that any remaining 70mm mag prints are irreplaceable, is a major consideration.