Ilford filter question

[redbandit]

If the enlarger is supposed to be "pure straight light" when set at 0 magenta 0 cyan and 0 yellow,,, and as well as being "contrast grade 2" at that setting in the beselar manual...

what happens if one uses an ilford contrast grade 2 filter in the filter drawer?

 

[MattKing]

If the enlarger is supposed to be "pure straight light" when set at 0 magenta 0 cyan and 0 yellow,,, and as well as being "contrast grade 2" at that setting in the beselar manual...

what happens if one uses an ilford contrast grade 2 filter in the filter drawer?

You end up with light that is of the spectral distribution that will give you something that approximates grade 2 contrast, and due to the use of the filter, your print will be approximately speed matched (on a high midtone) to the results you would obtain if you switched to other Ilford grade filters.
Without the filter, you lose the speed matching.

 

[snusmumriken]

If you use the Ilford filter, you will get grade 2, speed-matched as Matt says. What you get without the filter will be fairly close, but how close will depend on the enlarger. Colour heads vary in design. I find I get something close to grade 2 1/2 if I forget the filter.

 

[Doremus Scudder]

"Pure straight light" is what? The light coming from a tungsten-halogen bulb in a color head is somewhere in the neighborhood of 3200K, depending on which bulb you get. Non-halogen bulbs in condenser enlargers are around 2700K (approximately). If you're not familiar with "color temperature," it has to do with the spectral emission of heated objects; the hotter, the more blue component in the spectrum, the cooler, the more the spectrum is weighted to red.

Incandescent bulbs emit continuous spectra. Cold-light heads and LEDs do not, but those sources can be used as well for enlarging on VC paper. Ilford says this:

"Ilford Mulltigrade papers are designed for use with most enlargers and printers, that is, those fitted with either a
tungsten or tungsten-halogen light source. It is also suitable for use with cold cathode (cold light) light sources
and LED exposing heads designed for variable contrast papers. Other cold cathode (cold light) and pulsed-
xenon light sources may give a reduced contrast range."

As you can see, there can be a rather wide range of spectra getting to your paper from unfiltered enlarger light, depending on the light source you use. MG papers will deliver an approximate grade 2 from unfiltered tungsten light sources, give or take a grade. The variance is due to voltage fluctuations, age of the bulb, halogen or not, etc., etc.

Even with a Multigrade filter or using the filtration in a color head, the spectrum of the light source can make a difference, with the difference being greater for the middle-contrast filters that pass more of the complete spectrum available to it.

So, you may or may not get a print from unfiltered light that matches one made with an Ilford #2 Multigrade filter, and a filter made with either of the color head filtrations Ilford recommends for grade 2 from whatever color head your using may not match either of those. See here: https://www.ilfordphoto.com/wp/wp-content/uploads/2017/03/Contrast-control-for-Ilford-Multigrade.pdf And, you likely won't get prints that match from the same #2 filter used with different enlarger light sources. And then there's the age of your paper, etc...

There's a lot more variation in the whole process than we are often led to believe.

Best,

Doremus

 

[btaylor]

I find it convenient to just use the Ilford filters at all times for the speed matching feature. It makes it so easy to try another print with a different contrast without any messing around with the exposure. Grade 4 or above simply double the time or open one stop. A time and paper saver.