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Dark Orange
12-26-2007, 02:39 PM
There have been a couple of questions off-list that I will address here in the public area along with the other questions.

By the looks of things, many here may not be familiar with the workings of my image hosting site. I link to the image pages rather than the images themselves, which means you can get larger images by clicking on the little magnifying glass above the image and choosing the image size you want. This allows finer details (if any) to be read.

On my next visit, I shall attempt to document the emulsion manufacturing technique and equipment involved. While the builder has a top quality lab built for the task, with all the flasks and glass tubes and stuff, he is building special reaction chambers that sounds like it would be of interest to many of the posters and lurkers here. I'll put it in a new thread obviously. :)

I am not sure the bubble-trap and filter have actually been used yet. As for the bubble-trap, it is a simple chamber - emulsion/bubbles flow in, bubbles rise in the chamber, emulsion flows out. The screw in the top allows release of the air if too much accumulates. I'll make the assumption that they would go between the pump and the coating head, but shall get confirmation on that.

Finally, I wish to take this moment to thank Photo Engineer for filling in the details that I do not know. He is definately an asset to this forum.

PS. Did nobody notice the Kodachrome statement I made earlier? ;)

Photo Engineer
12-26-2007, 02:54 PM
I read it, and I know the problems having worked on it a very little bit.

PE

Dark Orange
12-26-2007, 03:22 PM
All problems are surmountable if you try hard enough. ;)

tim_walls
12-26-2007, 03:28 PM
PS. Did nobody notice the Kodachrome statement I made earlier? ;)

I read it, and cool though it sounds, I must confess I sort of wondered "why?"

I mean, making your own reversal process sounds very cool, but why would you base it on Kodachrome style technology other than, say, E6? Kodachrome seems colossally complicated.

Or is a Kodachrome type emulsion actually easier to homebrew?

If it's some particular image characteristic of Kodachrome you were after (e.g. colour balance say,) is there no way of trying to reproduce that characteristic but using an E6 type approach?


Of course, I accept as a perfectly valid answer to the "why?" question "because he can." That's the best reason going as far as I'm concerned :)

Dark Orange
12-26-2007, 03:43 PM
Of course, I accept as a perfectly valid answer to the "why?" question "because he can." That's the best reason going as far as I'm concerned

That's the whole reason behind the existance of this forum, innit? ;)

PHOTOTONE
12-26-2007, 04:05 PM
I don't think KODACHROME as an emulsion would be considered more difficult than E-6 emulsions to "make", rather the difficulty is in the processing, and the many more tightly controlled steps needed to successfully process it. Isn't Kodachrome actually three b/w emulsions (with carefully controlled characteristics) with filter layers in-between?

dmr
12-26-2007, 04:23 PM
PS. Did nobody notice the Kodachrome statement I made earlier? ;)

Yes, I did. :)

Although I will probably never coat film (my times in a wet darkroom can be counted easily on your fingers) I find threads like this fascinating.

What impresses me is that while many attempts to coat film or paper seem to result in so-so quality at best, this magic machine seems to be at least an attempt to get a reasonable degree of quality and consistency.

Even before you mentioned Kodachrome, when I saw the remarks about different layers being coated, I thought "Color, maybe?" :)

What impressed me most about this thread and this magic machine is that maybe a few companies whose business is dwindling don't have the strangle-hold on film use that we think they have! :)

Photo Engineer
12-26-2007, 05:11 PM
Kodachrome will require at least 9 emulsions and 6 layers to be coated. It will need either rem-jet on the back or AH under the emulsion layers. It is not a trivial task and will have to be built in groups of layers to get it right.

Good luck.

PE

Gatsby1923
12-26-2007, 06:35 PM
WOW I love this thread! I have been following it from day one. I almost want to build my own. I don’t have the know how but still this is a fun thread.

Dave M

Photo Engineer
12-26-2007, 07:06 PM
Hey, I would park my car in the driveway and put this in the garage just to have one. But, since I cannot, I'm doing the best to do it in a way that everyone can use.

But I sure do miss the coating machines. Quality is so much better.

PE

Photo Engineer
12-26-2007, 07:08 PM
I think that one of the moderators should make this a sticky!

PE

Dark Orange
12-26-2007, 08:02 PM
, I would park my car in the driveway and put this in the garage just to have one.

Funny you should mention that...

The filminator was dragged to a corner of the garage and walls built around it. It's there to stay. :) And the car is outside...

BTW, the term "Filminator" is of my own doing. All my photo titles are instant thoughts, and when first posting this I had a flashback to the Futurama episode with the "Crushinator".

I am glad this has shown you all what is possible to do in your own garage with a little knowledge and a lot of time. I hope this acts as a catalyst to your own creativity.

While this project was started with the aim of creating a coating machine with the best possible output with the most reliable consistancy between batches, it is probably overkill for the average user in here. Maybe Photo Engineer can suggest ways that the unit can be shrunk and simplified while still giving more consistant results than hand coating.

Photo Engineer
12-26-2007, 08:47 PM
Actually, I cannot help shrinking it. All I keep thinking about is how to expand it to allow 8" coating.

Also, I have lots of emulsion formulas in mind that might work well on this machine. I'm thinking right now about this nice 400 - 800 speed emulsion....... Oh well.

PE

rmazzullo
12-26-2007, 09:16 PM
I am blown away by the realization that a coating machine such as this has been built and can be made by others. Just the small details revealed in the photos and discussed have answered some questions before they were asked. Things like the Zenith pump (http://www.zenithpumps.com/products/bpb.htm), and the inline filters and traps, for starters. If you go to the larger original sizes of the photographs on Flickr, you can see some of the paths the film base takes through the machine. I am sure as more details emerge and are discussed, this will open up new possibilities that were only talked about not too long ago.

I am itching to see photos of the emulsion preparation equipment and reaction vessels.

Can you imagine a bunch (a whole bunch?) of these machines being built, and configured for film and / or paper? Even attempting color film? How about IR film, or experiments to recreate Tech Pan? The list seems almost endless.

I have located a source of bulk triacetate 120 (and other sizes) film base in NYC, but they have yet to get back to me as far as their minimum order requirements.

I wonder if you can use the same machine to coat and prepare roll film backing paper? The patents describe in good detail how the backing paper was made, and the what and why of the coated layers.

Bob M.

ben-s
12-27-2007, 04:49 AM
...I'm thinking right now about this nice 400 - 800 speed emulsion....... Oh well....

Damnit, PE, did you have to say that ;)

In theory, an 8" machine wouldn't have to be any longer, just a few inches wider... Or would the dryer would need to have a longer path to cope with a greater wet surface area?

I've been thinking more along the lines of a small (as in benchtop) 35mm slitting/perfing machine...

Photo Engineer
12-27-2007, 08:55 AM
Ben;

Dryer capacity at 5" width is not sufficient to handle 10" width. You either have to run at about 1/2 speed or make the dryer cabinets longer.

PE

Neanderman
12-27-2007, 11:22 AM
I wonder if you can use the same machine to coat and prepare roll film backing paper? The patents describe in good detail how the backing paper was made, and the what and why of the coated layers.

Bob:

Do you have these patent numbers? I'd be very curious to read them.

Ed

rmazzullo
12-27-2007, 12:19 PM
Bob:

Do you have these patent numbers? I'd be very curious to read them.

Ed

Hi Ed...

Here you go. The inventor on all of them is Ernest L. Baxter, and the assignee is Eastman Kodak. The latest patent builds on the prior ones, so I have listed all of the numbers I found:

2751309, 2646366, 2646365, 2262986, and RE21268

Bob M.

P.S. When you see the term "transparent zein" mentioned in the patents, some further research seems to indicate that it is another name for confectioner's glaze, of all things. This needs further checking.

rmazzullo
12-27-2007, 01:05 PM
Something else that comes to mind regarding the film coating machine: that it should be possible to scale this concept down to coat 35mm film base...providing a source is available. You could (potentially) use 35mm film projector sprockets and rollers for film transport.

Just a thought.

Bob M.

Photo Engineer
12-27-2007, 02:21 PM
Something else that comes to mind regarding the film coating machine: that it should be possible to scale this concept down to coat 35mm film base...providing a source is available. You could (potentially) use 35mm film projector sprockets and rollers for film transport.

Just a thought.

Bob M.

Since coated width must be narrower than the support for technical reasons, and the edges are defective, this method would either be extremely messy causing loads of defects, or produce a product that is underwidth.

It is better to coat wider and cut down. This has been the experience of ALL manufacturers to date.

PE