Paper Flashing.

[Andrew Moxom]

not to hijack this trhead, but what about the Daux Lite selective flasher tool? Anyone used it as there is one for sale on the APUG classifieds.

 

[tim rudman]

Tim, what flashing system do you use, and how does it link into your StopClock?

It's very simple. Instead of plugging my enlarger into the enlarger socket on the timer, I plug in a multi gang switchable extension cable (cut down to about 12 inches for tidiness). My enlargers and my distant 'omni flash/fogger' light are all plugged into the multi gang. Each one is switchable so when I hit the foot pedal any combination that is switched to 'on' will come on under the control of the timer.

I use a low wattage night light bulb in a flexible small desk lamp on a shelf at the back of the darkroom. The hood faces the wall/ceiling, thus dimming it further to allow quite long flash or fog times to use whilst burning in impossible areas. (i can move it easily to give a brighter light but then need a new flash strip, so mostly I don't, as i have it adjusted as I like it). This is some 12 feet behind me and the glow is omni directional by the time it gets to the paper. this is incredibly useful for flashing or fogging whilst burning in. I improvised this system almost 20 years ago and haven't improved on it. If you have my 1st printing book you can see an example of burning+fogging on page 83. it's an eye-opener what this can do.

I use also an enlarger adjacent to the one I am printing on for simple quick max-flash exposures through the second channel of the stop clock. This is hugely convenient as again I can switch enlargers on/of and switch channels in a moment.

I find this works so well for me that I have no need for the RH flasher, but I know many people like it and I don't want to give the impression that I have anything against it - I am a declared RH fan. For me though, having a flasher on the enlarger head would be a nuicance as I would have to re-calculate the flash exposure every time I move the head up/down.
Tim

 

[ChuckP]

not to hijack this trhead, but what about the Daux Lite selective flasher tool? Anyone used it as there is one for sale on the APUG classifieds.

I have one and use it often. Great for toning down those bright areas. My use is not very accurate as far as exposure goes. I just use a best guess to start with and work from there. You can also get some variation between prints if you don't get the distance the same each time. This is usually not noticable unless you compared two prints side by side. The object is to get distracting hot spots toned down. I usually also do some burning in the area.
The Duax Lite exposure is normally done during the print exposure so you can easily see the area being exposed. If not you have to guess at the right location.

For flashing a full sheet or large areas using a mask I use an enlarger and timer. You can use an old print to cut a rough mask that allows only a certain area to be flashed. Move the mask during exposure like in dodging. You could setup a holder for the Daux Lite and use it to flash the larger areas but turning it on and off is a problem. Would need to uncover and cover the print by hand to do the timing.

The light is really an advancement of the old penlight used for years by people for small area flashing. You could easily build something out of a penlight to try. The big advantage of the Duax Lite is the easily adjustable intensity and various spot sizes.

 

[tim rudman]

I have one and use it often. Great for toning down those bright areas.
SNIP SNIP
The light is really an advancement of the old penlight used for years by people for small area flashing. You could easily build something out of a penlight to try. The big advantage of the Duax Lite is the easily adjustable intensity and various spot sizes.

Ah, this brings back memories that I had long forgotten.
Gene Nocon showed me threshold flashing back in about 1980 (ish). I had not heard of the concept 'til then. But I had previously devised my own system for small hot spots, which started with a penlight and black paper funnel and then got adapted to a fibre optic 'wire' (or whatever it's called) taped onto a penlight with black tape and used as one would a dodger but to burn or fog small areas accurately.
Back in the 60's and 70's it was common practice to slightly overdevelop film. Since I improved my negative processing from the late 80's on I don't get such hot spots and my printing is more interpreation than rescue I'm glad to say.
Tim

 

[tim rudman]

Why do you flash the paper? What is the effect on the image? Thanks!

Janet

This is the into para on one of my printing workshop handouts Janet. I can send you more info if you want.
Tim
...
Printing paper has an ‘inertia’ when first exposed to light. It requires a surprising amount of light exposure before it will register any tone at all on development.

‘Pre Flashing’ is a technique of exposing paper to a carefully controlled and measured amount of uniform ‘white’ light up to, but not exceeding, the paper’s inertia threshold.

The effects of pre-flashing are:
- To shift the overall image-forming exposure away from the toe of the paper’s sensitivity curve.
- Altering (lowering) contrast – useful for in-between grades with graded paper
- Extending tonal range– graded & VC papers
- Improving detail or tone in highlights – graded & VC papers
- Making subsequent highlight burning-in easier, with less risk of ‘dark haloes’– graded & VC papers.

NOT all prints require or benefit from flashing.
continued ...

 

[pentaxuser]

Janet. Tim maybe can't plug his book or feels it inappropriate but I can. Get hold of the "Photographer's Master Printing Course". It was always good value but is now sold at prices which make it amazing value. It'll cover everything and more that most printers will ever need to know.

pentaxuser

 

[tim rudman]

Janet. Tim maybe can't plug his book or feels it inappropriate but I can. Get hold of the "Photographer's Master Printing Course". It was always good value but is now sold at prices which make it amazing value. It'll cover everything and more that most printers will ever need to know.

pentaxuser

Thank you. You're a Gentleman sir (or Lady - I can't tell )
Tim