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AgX
11-07-2012, 11:28 AM
The rotating dies method is the way to go if you are doing a lot of film and want to run fast. The flat die method would be easier for a hand operated, low quantity production run. We have small hand operated machines at work similar to this for punching polyester sheet.


The funny thing is that it is just the other way round the industry does it...

Actually it would be even harder to achieve high precision with rotating tools.

dwross
11-07-2012, 12:01 PM
Denise,

Can you point out which exact paper you are talking about? For a while, I've been contemplating to try to make a few rolls of 122 film for my Kodak 3A camera. It should not be difficult to manufacture spools from 120 leftovers, and I think I have most of the ingredients for the emulsion, but the lack of backing paper has been stopping me.

Thank you,

Eugene.

Hi Eugene,

I am very satisfied with Hahnemuhle Ingres (German Ingres). Black. 95 gm/m2. I got it from Daniel Smith Art.

As part of the "mission" of The Light Farm, I'm always on the lookout for the materials we need that cross-purpose from other fields. If I have any say in the matter, handmade silver gelatin emulsions will be make'able forever, with little to fear from disappearing materials. Beyond the sensitizing chemistry for modern color films, silver nitrate seems to be the one and only real issue, and that even can be made from basic components (note: I am absolutely not recommending that for the amateur.)

But, back to the paper. I also have many hundreds of feet of the the paper used for film backing (got it from a film company in Hollywood.) Email me at editor@thelightfarm.com with your address and I'll send you a length of it to try. I think you'll enjoy making your own film. Very satisfyingingly cool.

p.s. One minor issue with diy roll film is that the backing paper isn't as lightproof at the edges as commercial rolled film. I recommend changing film in very subdued light. With the Hahnmuhle, make that very, very subdued light.

d

Photo Engineer
11-07-2012, 12:09 PM
Just a note for Chris on the slitter and chopper. Much of the RIT equipment was made at EK and used there originally.

Also, the slitters and perfers became dull with use and had to be replaced on a regular basis. Kodak used rotating dies for all of this. As Chris said, this is all very simple in theory! ;)

Now, as for backing paper and etc, yes, paper is available and yes, 120 is a good target, but grain and sharpness are what might bite us even in 120 size, and so this is why I am targeting 4x5 and larger on film or plate. I have quite a few glass plate holders and hope to coat them and some film for use in my 4x5 camera.

BTW, Mark and I will be teaching a workshop on Bromoiodide emulsions in March 2013.

PE

dwross
11-07-2012, 12:24 PM
Ron.

When you say "120 is a good target, but grain and sharpness are what might bite us even in 120 size..." you make it sound like 120 fim is still theory. Nay, nay. I shot handheld with various 120 cameras all summer -- ortho film, approx ASA 100, almost indistinguishable from TriX grain under high magnification. I'm actually sitting here this morning writing a series of tutorials for TLF, including diy 6x9cm negatives enlarged onto diy ClBr paper (ordinary incandescent bulb enlarger.) In the meantime, I already have info on TLF, starting here and going for the next three pages. http://www.thelightfarm.com/cgi-bin/htmlgen.py?content=04Apr2012.

btw, congrats on the dry plate workshop. I'll be sure to get it advertized on TLF!

d

Photo Engineer
11-07-2012, 01:25 PM
Denise, I said "MIGHT", not will. You yourself have said here that the grain at ISO 100 is about like TriX. That is nearly 2 stops loss in speed / grain. Not very good but usable. You make my point. It depends on what you expect from your film. A lot has to be done on this. What you present is a very fine 4x5 emulsion in fact, but a just usable 120 emulsion, at least to some.

And, as for the workshop, I said nothing about dry plate. Please see the details here: http://www.eastmanhouse.org/events/detail.php?title=photo-workshop-3-2013

PE

anikin
11-07-2012, 01:25 PM
But, back to the paper. I also have many hundreds of feet of the the paper used for film backing (got it from a film company in Hollywood.) Email me at editor@thelightfarm.com with your address and I'll send you a length of it to try. I think you'll enjoy making your own film. Very satisfyingingly cool.


Denise,

Thank you for your offer. E-mail sent. I just wish I could visit and see in person how you coat your film. I'm sure there are a lot of tricks to learn...

Eugene.

dwross
11-07-2012, 02:05 PM
You're a hard man, Mr. Mowrey, but these days I just chuckle and move on. I'm having too much fun, and my harshest critic (me:)) is very satisfied with my progress.

re your workshop: You may want to reword the course description. It reads "...This is a silver bromide emulsion suitable for coating developed out printing paper or plates to be used in the camera..."

I would take that to mean students will be putting their emulsion on paper and glass (i.e. dry plate.) But if it's just emulsion making without a coating and processing component, it would probably be best to spell that out.

dwross
11-07-2012, 02:12 PM
Denise,

Thank you for your offer. E-mail sent. I just wish I could visit and see in person how you coat your film. I'm sure there are a lot of tricks to learn...

Eugene.

We'll have to make that a date after the Rainy Season! If nothing else, I'm thinking about something insane like an Open Studio Saturday with demos sometime early summer 2013. I'm hoping that could be a fun and useful addition to the web tutorials I'm trying to pull together by New Year's. But, typing here won't get it done!

Best of luck and fun,
d

anikin
11-07-2012, 02:27 PM
We'll have to make that a date after the Rainy Season! If nothing else, I'm thinking about something insane like an Open Studio Saturday with demos sometime early summer 2013. I'm hoping that could be a fun and useful addition to the web tutorials I'm trying to pull together by New Year's. But, typing here won't get it done!

Best of luck and fun,
d

What a great idea! Let me know if you need help with organizing that.

Photo Engineer
11-07-2012, 02:51 PM
I hope you all have fun at the Open Studio Saturday.

As for being hard, I am merely being accurate in terms of "might" vs "will" in what I write. As for the workshop, it is intended to be very comprehensive. Please note that it is 4 days long, not 3. And, common sense would tell us that making an emulsion and then doing nothing with it would not be very useful. Of course we will expose by a variety of methods and then process the exposed materials.

We made a batch of the emulsion last week here at my home for testing, and we are training two interns to work with us during the workshop, which we expect to be a big success. The person in the photograph is from the west coast and is an avid photographer.

AAMOF, I have a lot of 120 coating and "packaging" material here, but I do believe that 4x5 plates and films have a very big future in analog photography, both manufactured and do it yourself. One of the big problems with 120 is, as you say Denise, edge fog. Real 120 backing is feathered along the edge and is overwidth to prevent fogging. Take a look at real 120 paper and you will see what I mean.

No Kodachrome yet though! :D

We are pretty far off topic.

PE

kb3lms
11-07-2012, 03:16 PM
For backing paper, try Pacon 57305 Fadeless Art Paper, 48" x 50' roll, Black. You can get it from Amazon or any number of other places fairly cheap. A roll should last a long time.

It is an opaque 20lb paper, like stadard white office paper, black on one side and white on the other. One layer will pass some light but two will not. You cut strips to the same shape and size as a manufactured backing paper and put the black side towards the film and the white side out. You can write frame numbers and whatever else you like on the white side. Put a layer of scotch tape around the ends where they fasten to the spools as the paper is not as strong as regular backing paper and will tear if you don't give some reinforcement but that was the only strength problem I have had.

I have changed homemade several 620 size rolls in room light with no problem. (The emulsion used was a batch of TLF#2 @ ISO ~20.) I had no issues with the red frame number window on the camera but the emulsion was not spectrally sensitized, either. There were no problems with edge fog.

-- Jason

kb3lms
11-07-2012, 03:29 PM
IDK about being able to produce acceptable grain for smaller sizes. As I have mentioned elsewhere, I take scraps from my 120 size coatings and cut them up as sigle size 35mm frames. The grain is certainly noticeable, but not that bad. "Front Flower Bed" is my favorite 35mm example:

https://www.dropbox.com/s/jmljo9oh57utf14/FrontFlowerBed.jpg

This was scanned on my Nikon LS-40 through Vuescan. It's been printed as an 8x10 and the grain is OK. Being non-modern film it is a little hard to print, though, and I don't feel that I've gotten a really good print but that's OT.

It seems logical to me that as we all gain more experience the emulsions will get better. What is important is for all of us trying these things to keep posting / sharing what we learn.

-- Jason

kb3lms
11-07-2012, 03:46 PM
Yesterday at GEH I actually got to lay eyes on an old Kodak perforater ...... in the labs down here I've come across these two little film splitters with stickers that say RIT on them. They are for splitting 4" film down to 35mm, and the other is for splitting 35mm down to 16mm....

Hey Chris,

Could you snap some pictures of these gadgets? It would be great to see what they look like.


Now, as far as punching is concerned, making a small punching block may be harder than you think. One of my projects that has held up my emulsion work was trying to punch 35mm because that is what I ultimately want, too. I was trying to punch acetate with 6 pairs of holes spaced for 35mm. Have not yet tried PET but I would expect it to be harder to do. Issues I came across:

1) Quite a bit of pressure is required to punch more than about 6 holes so you need a fixture with some leverage. I would expect PET would need more pressure.

2) Hanging chads are a real problem and they are hard to avoid without having to cut them off manually. Chads may be less of a problem with PET.

3) Round holes did not work reliably in any (Pentax SLR) camera I tried. Lot's of problems with jamming. You need a rectangular hole but I don't think it needs to exactly match the ANSI spec. There is some tolerance.

I had no real machining tools to do this and was just working with a dremel tool, nails (with the point cut off and then modified with a v-notch in the face) for the pins and aluminum for the die. So, I am not saying it cannot be done, these were just some issues that I found.

-- Jason

Photo Engineer
11-07-2012, 06:09 PM
Jason, that photo is quite good, but I can see the grain. Did you notice that there was quite a bit of flare as well? This would need a good AH dye or absorber dye. And, unfortunately would cost you up to 1 stop in speed. This increases the speed / grain ratio even more than I mentioned in my previous post.

Just FYI, the attached item shows how we make emulsions, coat film, and do the final operations of slitting, chopping, perfing and spooling. My thanks to the unknown artist who did this.

PE

Mr Bill
11-07-2012, 06:15 PM
Originally Posted by Steve Smith

The rotating dies method is the way to go if you are doing a lot of film and want to run fast. The flat die method would be easier for a hand operated, low quantity production run.


The funny thing is that it is just the other way round the industry does it...

Actually it would be even harder to achieve high precision with rotating tools.

AgX, the system I saw used rotary dies - they were trying to get out of the "flat die" method, which nevertheless was also used for automatic high production use. It's just that the advantages of the rotary system made it worthwhile; there is no risk of rubbing against machinery - with a rotary system, the moving film web can just "kiss" against the punch/die set which is moving at the same speed. Note that this was some years ago, when professional film production was probably at a peak.

kb3lms
11-07-2012, 06:21 PM
Hi PE, that frame was scanned at 2900 dpi or whatever the Nikon does so you get the warts and all. Optically printed at 8x10, it looks about like Tri-X. I consider this to be a starting point. At least this batch did not go through the spoiling dept like the last one. :D

The flare is what makes it different! Seriously, I have some thoughts on AH, but as you say they all would cost speed.

Brian C. Miller
11-07-2012, 07:07 PM
Just FYI, the attached item shows how we make emulsions, coat film, and do the final operations of slitting, chopping, perfing and spooling. My thanks to the unknown artist who did this.

The art style looks like it was done by one of the "usual gang of idiots" at Mad Magazine. The one I'm thinking about did the last page in the magazine, before the "fold-up" page.

(Memorable: man walking down the street past various shops and signs: "Phonebone's Glasses" with a huge pair of glasses, "Phonebone's Umbrellas" with a huge umbrella, "Phonebone's Wigs" with a huge wig, "Phonebone's Bandanas" with a huge bandana, "Phonebone's Shoes" with a huge pair of shoes. Then the fellow rounds the corner and there's a giant standing there wearing the glasses, holding the umbrella, wearing the wig and shoes, and the bandana is wrapped around his waist. Another sign reads, "Phonebone.")

Mr Bill
11-07-2012, 07:19 PM
Now, as far as punching is concerned, making a small punching block may be harder than you think. ... Issues I came across:
...
2) Hanging chads are a real problem and they are hard to avoid without having to cut them off manually. Chads may be less of a problem with PET.
...
3) Round holes did not work reliably in any (Pentax SLR) camera I tried. Lot's of problems with jamming. You need a rectangular hole but I don't think it needs to exactly match the ANSI spec. There is some tolerance.

I had no real machining tools to do this and was just working with a dremel tool, nails (with the point cut off and then modified with a v-notch in the face) for the pins and aluminum for the die. So, I am not saying it cannot be done, these were just some issues that I found.


Jason, thanks for the reality check. These are some of the issues I would expect. I think the solution to "hanging chads" is in extraordinary precision in the centering and clearance between punch and die. I'd guess that the speed of the punch is also a factor, as might be use of a high vacuum below the die set.

Re: round holes: I don't think these are at all desirable for film transport (in cameras, etc). But "round" makes it simpler for a home machine shop to make punch and die sets, and to have these precision-aligned (within reason). It wouldn't be necessary to have the rotational alignment near perfect, as it would be with rectangular punches.

I'm sure it can be done, I'm just saying the reality is a lot more difficult than it appears.

Steve Smith
11-07-2012, 07:20 PM
Something we are about to experiment with at work for cutting 0.125mm polyester is a chemical etched tool. This might be suitable for small scale perforation punching and would be cheaper than a traditional male and female die set and probably cheaper than a steel rule die.

Everything you ever wanted to know about cutting tools but weren't interested enough to ask: http://www.dieco.com/index.php/ddin-library/37-options-to-consider-in-diecutting


Steve.

Photo Engineer
11-07-2012, 07:34 PM
AFAIK, Kodak made or had made for them, custom perfing and slitting and chopping equipment. The dies were replaced on a regular basis. The ones I saw were rotary.

The cartoon style is Don Martin.

And Jason, yes, we lose speed and that is why I said that this puts us in a worse position for speed/grain. We would probably turn an ISO 100 material with TriX grain into an ISO 25 - 50 material with TriX grain. Then the question is, is this suitable for 35mm. Probably not. For 120, probably but maybe marginal. For 4x5? Probably just right. But, IDK until I do the experiments. I have the AH dye here. It is an Oxonol dye that dissolves in developer.

PE