Easy way to perforate 35mm

[holmburgers]

Here's what you need... http://www.brianpritchard.com/WW2%20Perforator.jpg

[Scheimpflug]

Then, the actual perforating can be done in dark and is quite quick and easy to do with nitrile gloves etc.

Yes, last time we made emulsion was this; http://www.apug.org/forums/forum205/...t-results.html . And yes, we plan on making 35mm. I didn't buy this splicer just to test it .

If you are making & applying the emulsion yourself, is there any reason not to perforate the film base first, in the daylight, and then apply the emulsion afterwards?

It seems like a lot of extra work to have to perforate it in the dark...

[Rick A]

Sorta reminiscent of the 2000 elections, hanging chads as it were.

[dwross]

Cute! And just when I thought there weren't any more toys to buy.

To address two points: You wouldn't need to work in total darkness, unless you had panchromatic emulsion (probably unlikely). It's very easy to see in red light, especially if you're lit with red LED's. Unless you had a magic loop coating machine, you'd need to coat first, let the emulsion dry, and then cut out the film strip and perforate it. If you perforated first, the emulsion would fill in the holes. Dry emulsion is almost as tough as plastic.

Attachment: The selvage from a 32" strip of 120 film.

d

[hrst]

If you are making & applying the emulsion yourself, is there any reason not to perforate the film base first, in the daylight, and then apply the emulsion afterwards?

As Denise said, it's not possible because the emulsion flows in the perforations (and outside the film), making a mess. I coat with a coating blade and the requirement for usable coating is that the film base is flat (without any holes ) and wider than the coating blade so that the blade runs on the film base, inevitably leaving some uncoated area on the edges.

So, the easiest way is to coat a wider coating, for example, 15 cm wide coating on 20 cm wide film base, and then cut it down to e.g. 4 slices of 35 mm film, and then perforate. You'll also get more than one roll of film with one coating, which is very nice because hand-coating on the table restricts the length quite a bit (I'd say 135-24 is practical maximum).

It seems like a lot of extra work to have to perforate it in the dark...

Well, the coating has to be done in the "dark" anyway (and the final steps in emulsion making, after sensitizing dyes are added), and perforating is quite easy compared to that. This is why ortochromatic film is so much easier to make, as you can actually use red safelight. If you are going to do panchromatic, it's better to buy night vision goggles and use IR light. I have bought the goggles so I can do panchromatic one day, but it will take time before I'm at that point. I have actually done nothing regarding emulsion making in a past few months, but I'll be back at it again soon.

[vedmak]

I have 2 boxes of unperforated Agfa Copal, can any of the lucky splicer owners consider perforating those for me? Pm me for details :-)

[hrst]

The perforator I showed here is not very fun to use for larger amounts of film, and the result is not that good. I wouldn't consider using it for perforating long, existing rolls of non-perforated film... But, for your own coatings, it's completely different! When you have already done a huge amount of work when making the emulsion from scratch, and coating it, and it's your very own product and the quantity is low, then this kind of makeshift perforating is next to nothing to perform . Everything's so relative...

[onnect17]

Sorta reminiscent of the 2000 elections, hanging chads as it were.

I was thinking exactly the same !!!

I hope the education in this school is free. What a waste of time.

[dwross]

I have actually done nothing regarding emulsion making in a past few months, but I'll be back at it again soon.

Great to hear! You were making real progress. Looking forward to seeing more of your accomplishments!

[hrst]

Great to hear! You were making real progress. Looking forward to seeing more of your accomplishments!

Thank you for your supporting words!

I'm sure I will never give up emulsion making and coating, it's just so interesting and so much fun. And, it's nice to have this community here to share results with.

It is just that I have a bunch of other interests, too, to take my attention away from emulsions, but then after some time, I start feeling I want to get back to emulsions again for a while.

Heck, if I dedicated all of my time for emulsions, I'd already have a 3200 ISO color neg film with the grain of Ektar and sharpness of Technical Pan!! That'd be boring!

Currently I'm at the point that I should make my working prototype of corona treatment killing machine a bit more compact, reliable and safe, so the troubles in coating and the time wasted there would go down. I have already made my emulsion making so automated using the syringe pump...