Idiotically simple question on VC & Filters

[Mike Keers]

Hey gang,
If this has been answered before, I apologize, several searches didn't turn up an answer. I'm new to VC papers and filters after being away from the hobby for decades. I've had some fun blowing thru several hundred sheets of various old FB graded papers, and finally bought some VC stuff, and a filter set.

My simple question is really a clarification; I've read in several books and the paper data sheet itself that VC paper exposed with no filters can be assumed to print at about Grade 2.

I've also read that some people normally start out with a #2 or 2-1/2 filter.

So my question is, if the paper will print as #2 with no filter, what happens when you use the #2 filter? Is the contrast upped? No change? Simple minds need to know
mike

 

[trexx]

I've also read that some people normally start out with a #2 or 2-1/2 filter.

So my question is, if the paper will print as #2 with no filter, what happens when you use the #2 filter? Is the contrast upped? No change? Simple minds need to know
mike

The filter will cause the exposure time to, in general, double from the one with out a filter. If the filter brand is the same as the paper then with all else equal. A print with the #2 filter should appear the same as the print without. The reason to start and do all prints with a filter is so when you decided that the print needs more or less contrast the exposure dose not need to change.

The theory is that 00 to 3.5 have the same printing density and 4-5 have twice that. It may be a good starting point but filters can be off from that I reevaluate the exposure. So for me it does not matter if a filter is in place.

A real good book to pick up is Steve Anchell's Variable Contrast Printing Manual.

TR

 

[ann]

in theory one would think that a print made with a grade two filter and on made without a filter and the paper being a grade 2 default that they would look alike.


however, we have run test in our lab with several different enlargers and the prints do not look the same.

your milage may vary.

 

[JBrunner]

Different enlarger lamps and lenses are going to have subtly different "white" light, and different papers will respond in kind. All things being equal grade 2 +1 stop should print the same as white light, but all things are rarely equal.

 

[ann]

j,
isn't that the truth

one day just for fun, i took one negative and made a print from 11 different enlarging stations. Same fstop, same times, same grade, same development times, paper , etc.

And of course, none of them look the same.

I also show them to my students to remind them why they need to work at the same station and not move around from week to week.

 

[CBG]

Any two incandescent lamps* with a differing ratio of blue to green light will produce differing contrast - with or without a filter over them - at least in the middle contrast ranges.

*or any lamps that produce both the needed blue and green spectrum

C

 

[Vaughn]

Ann, you are correct, of course, but there are so many other variables that in the end it may not make a significant difference if a student uses the same enlarger. Bulbs age and change...so even the same enlarger will not give the same results over a period of weeks. Then there is the age and use of the developer, new packets of paper from different emulsion runs, age of the contrast filter, et al. But as much as I try to keep all the enlargers well maintained and aligned, each has its own "personality" and it does help to learn the quirks of the enlarger one is using (and also the timer that is tied to the enlarger)!

We have two banks of enlargers -- 23C's and D5-XL's. Students do tend to use one type over the other...and many students do have their favorite enlarger. But since we have 19 enlargers and about 125 students per semester, getting one's favorite enlarger is not a given on any open lab period.

Vaughn

 

[ann]

i understand that, that wasn't the point.
i is just that one can't always take theory as the absolute . there are many variables as you have already suggested, along with others not mentioned that will effect the process.

when one uses the same equipment it is easier to become more familar with it"s ever on going changes.

with our situation, it is easier to control who is using which enlarger at a given time .

 

[Vaughn]

Like I said, Ann, you are correct. And there might be a few out of our 75 beginning students who can actually see the subtle differences created by using different enlargers!

Vaughn

 

[Mike Keers]

Thanx for the helpful answers, all. Additionally, I hadn't realized that using the lower-numbered filters in the first place changed the exposure time--the literature merely pointed out that no correction was necessary up to #3, and then one stop for the balance upward. Being of simple mind and a trusting nature, I assumed they meant that literally, like with some camera lens filters. I haven't actually started using the filter set yet, so this little tidbit has probably saved me some backtracking and 'unlearning'. Thx!