Jacro 35mm UV Film

[Andrew O'Neill]

Jacro sent me several complementary feet to play around with... and I did! To familiarise myself with this stuff, I started off contact printing older 35mm negs. When we get some decent sunny days, I'll venture outdoors with the K1000 loaded up with this unconventional film...

 

[Neal]

Very cool.

 

[tom williams]

Andrew, you mention 26 sconds as an exposure time for the thinnest of the negatives in your video (thanks for that) - but Jacro mentions 10 minutes/f8 for an exposure, on a sunny day. You also have a walking person in one of your negatives, unblurred - also mysterious if the 10m/f8 figure is to go by. Even if the aperture opens 6 stops, the exposure would be several seconds long, starting from 10m/f8. No doubt I'm missing something - lay it on me!

 

[Andrew O'Neill]

Andrew, you mention 26 sconds as an exposure time for the thinnest of the negatives in your video (thanks for that) - but Jacro mentions 10 minutes/f8 for an exposure, on a sunny day. You also have a walking person in one of your negatives, unblurred - also mysterious if the 10m/f8 figure is to go by. Even if the aperture opens 6 stops, the exposure would be several seconds long, starting from 10m/f8. No doubt I'm missing something - lay it on me!

As mentioned in the video, I contact printed existing negatives onto the UV film. I show the negatives at 57 sec into the video... I also stated in the video, that I will be loading up a camera to take photos outdoors, once we get some decent sun

 

[Daniela]

Cool! Nice to see the process.

 

[Dustin McAmera]

Amazing! (Too bad we never get UV light in the uk!)

 

[Sirius Glass]

Amazing! (Too bad we never get UV light in the UK!)

Actually UV light goes through clouds which is why one can get a sunburn on overcast days.

 

[tom williams]

As mentioned in the video, I contact printed existing negatives onto the UV film. I show the negatives at 57 sec into the video... I also stated in the video, that I will be loading up a camera to take photos outdoors, once we get some decent sun

Right - I actually saw the preamble to the video but didn't absorb it (distracted by my donut). Thanks.

 

[grahamp]

Their web site indicates that letting the (latent?) image fade over seven days or so and then heat developing will generate a positive. Curious stuff.

 

[Andrew O'Neill]

Right - I actually saw the preamble to the video but didn't absorb it (distracted by my donut). Thanks.

Now I want a doughnut. Thanks a lot...

 

[Andrew O'Neill]

Their web site indicates that letting the (latent?) image fade over seven days or so and then heat developing will generate a positive. Curious stuff.

Something that I will most likely try....but I would have to be confident that my initial exposure was adequate.

 

[pentaxuser]

It's a cool and intriguing process and was completely beyond my ken until I discovered this thread but without wishing to sound underwhelmed by it I cannot work out what the advantages of it is beyond its ability to make a copy of a standard neg such as Andrew has done

What does it do beyond that?

Thanks

pentaxuser

 

[Andrew O'Neill]

It's a cool and intriguing process and was completely beyond my ken until I discovered this thread but without wishing to sound underwhelmed by it I cannot work out what the advantages of it is beyond its ability to make a copy of a standard neg such as Andrew has done

What does it do beyond that?

Thanks

pentaxuser

That is what I'm going to look into for part 2.
As far as copying negatives, to get another negative, you would probably have to make your exposure, then let the latent image fade of a seven day period (according to their website), then zap it with UV. Apparently you get a reversal, when you heat process it.
I would prefer it if they packaged up sheet film sizes.

 

[Rick A]

Great video Andy, had a cup of my favorite tea and an apple fritter whilst watching.

 

[pentaxuser]

That is what I'm going to look into for part 2.

I would prefer it if they packaged up sheet film sizes.

Yes part 2 might or might not be interesting. Strangely I thought immediately that one of the advantages of this stuff might be the ability to make large negatives such as 8x10 or even larger from even bigger LF cameras such as yours and develop without even having any of the equipment that is normally needed but lack of sheet film sizes means that this is not possible

Apart from a kind of "party trick " interest that may not last, I wonder if there is really anything else that makes it an advantage to have but I look forward to being informed to the contrary

pentaxuser

 

[Andrew O'Neill]

Yes part 2 might or might not be interesting. Strangely I thought immediately that one of the advantages of this stuff might be the ability to make large negatives such as 8x10 or even larger from even bigger LF cameras such as yours and develop without even having any of the equipment that is normally needed but lack of sheet film sizes means that this is not possible

Apart from a kind of "party trick " interest that may not last, I wonder if there is really anything else that makes it an advantage to have but I look forward to being informed to the contrary

pentaxuser

Well, I could easily take one of the 35mm contacts I made, stick it in the enlarger, and make an enlarged negative on xray film, then contact print that in the Alt. process of my choice (once the DR has been matched)... but then I could just stick any ortho 35mm neg in the enlarger and make an enlarged negative. Still looking forward to making some in-camera exposures (we finally have some sun!), party trick aside.

 

[Andrew O'Neill]

Great video Andy, had a cup of my favorite tea and an apple fritter whilst watching.

Apple Fritters are my favourite! Washed down with a white, Orange Pekoe.

 

[Chuck1]

That's it I'm going to get a fritter tomorrow!

 

[Andrew O'Neill]

 

[Daniela]

It's a cool and intriguing process and was completely beyond my ken until I discovered this thread but without wishing to sound underwhelmed by it I cannot work out what the advantages of it is beyond its ability to make a copy of a standard neg such as Andrew has done

What does it do beyond that?

Thanks

pentaxuser

In my case, I'd really like to give it a try because I work with kids and this would make the process speedier and easier. I'm waiting for sheet film, though.

 

[UnderwoodPhoto]

Nothing new. I still have a roll from 40 yeats ago thats still good. Only seen it in 35mm. Can not be used in a camera. Expose until there is a faint image on the film then develop using a hair drier. Here are the details.....

Vesicular films use an inexpensive process to create use copies of film and fiche. These films take advantage of the fact that diazonium salts produce nitrogen as they decompose when exposed to UV radiation. In vesicular films, diazonium salt coating is sandwiched between two base layers. The film is placed in direct contact with a master film, exposed, and developed by heating the film. As a result, the image will always exhibit slightly raised areas made of small bubbles.


The vesicular film base must be polyester because acetate cannot tolerate the heat used in processing. Mechanical pressure frequently causes damage to vesicular film, as pressure will collapse the bubbles. Another major vulnerability becomes apparent at high temperatures (such as those caused by heat-emitting viewing equipment or ambient air temperature) which cause the base material to soften, allowing the gas contained in the bubbles to expand. As the bubbles grow in size, they can rupture, leaving patches of clear film where the image was formerly visible. This is called bubble migration or movement.

 

[Rick A]

Apple Fritters are my favourite! Washed down with a white, Orange Pekoe.

Rooibos tea. I can take or leave donuts, but I can't resist an apple fritter.