Ilford MG filters faded - how to know ?

[PeterB]

Hi folks,

I was printing today and when switching from an Ilford Multigrade (MG) filter number 3.5 to 4, the print suddenly went VERY flat and muddy rather than having more contrast.

I'm attaching two shots of my 12 filters on a light box so you can see the problem with #4 (and probably #4.5). One thing that had me thinking they were OK, is that some ads (like Dead Link Removed from Adorama) show the #4 filter as being more orangey/yellow than magenta in colour (as mine is).

I would like to check if my filters are past their used by date.
How can I know when they have faded out of specification so this doesn't catch me by surprise again ?

I can't believe I've had this problem for so long and not noticed it. Admittedly I don't use filter 4 much but even so....

I've had the filters for about 10-15 years, and use them only a few times each year (I also left one in the enlarger while it was on and hot for a couple of hours though - my enlarger takes incandescent tungsten globes)

rgds
Peter

 

[alkos]

My new #4 is quite transparent, "salmon" colour, as the one on the photograph you've attached. Your 00 looks much more yellowish than mine, though.

 

[Ian Grant]

When or if they fade it tends to be uneven, as in your images.

Back in the UK I have 4 or 5 sets of Ilford filters, one set from the 50's which are all still OK (the 50's set usest he reverse filtration - tyellow= contrast). But I have had a set fade badly stored in dampish conditions it's not just light that causes failure.

Ilford recommend replacement roughly every 5 years, but my two below the lens sets are still fine after about 15 yeras of use, and give a full range of contrasts.

Ian

 

[scinysnaps]

Hi folks,

I was printing today and when switching from an Ilford Multigrade (MG) filter number 3.5 to 4, the print suddenly went VERY flat and muddy rather than having more contrast.


I had EXACTLY the same problem as you did when I switched from 3.5 to 4 expecting more contrast... instead it got even muddier...
My filters are about 20 years old, and #4 is the same salmon color and not the magenta hue of 3.5

I have no idea what the problem is...

 

[Jon Shiu]

I think a number 4 filter (and 4.5 and 5) is calibrated to require 1 stop more exposure than a 3.5 filter (and lower). So, if one didn't know that, it might be part of the problem.

Jon

 

[ic-racer]

I did a number of tests on the Ilford filters and I believe the 4-5 filters are special 'narrow band' filters. If you measure them with a standard color densitometer or baseboard color meter the measurements don't make sense.

So, if the filters are old and not doing what you expect, I'd just get some new ones, they are relatively inexpensive. A set of new filters won't cost much more than a step wedge (which is what you will need to test the filters).

 

[erikg]

They shouldn't be much older than your underwear. Both should be swapped out for new every so often even if you don't think they need to!

 

[PeterB]

I had EXACTLY the same problem as you did when I switched from 3.5 to 4 expecting more contrast... instead it got even muddier...
My filters are about 20 years old, and #4 is the same salmon color and not the magenta hue of 3.5

Scinysnaps, it is reassuring to know you have the same problem I do.

I seems that #4 truly does begin life with less magenta than #3.5, evidenced by the Ilford site here and Adorama's here.

Thanks also to Alkos, Jon, Ian, ic-racer and Erik for your replies

I'll buy some more today and report back.

regards
Peter

 

[Mike Wilde]

On the testing front, a step wedge is a very useful thing.
Contact print the thing, and visually count the number of steps between first non white and first non black and know how the filter is working with known good paper

or, how old out of date paper reacts to given filtering,

or figuring out dichroic filtering needs to be give equal contrast steps with new or out of date paper.

I started with a 1/2" x5" one gifted to me , and found it so useful, that I bought a 6x6 one from Stouffer.

 

[Martin Aislabie]

I have had the same issue with fading Ilford Filters - see this thread - (there was a url link here which no longer exists)

I first noticed inconsistent results as I stepped up Filter Grades while printing.

I used a Step Wedge to judge the range of tones from black to white each filter would give me.

It took an afternoon of test work but it was worth while.

I bought a new filter set and have never looked back

Martin

 

[edtbjon]

Hmm...
I havn't used my densitometer for some time now. (Testing film after film after film for various developers just became too much...) But now I have found a very good use for it again.
Thanks guys and have a happy new year.

//Björn

 

[Simon R Galley]

Dear All,

It is highly dependant on the amount of use ( exposure to light ) and care of the filters, we always were told that they had a 5 to 8 year life and to change them for optimal performance after approx 5 years.

Simon. ILFORD Photo / HARMAN technology Limited.

 

[PeterB]

Thanks Simon ! My new ones are arriving tomorrow.

I have thought of an easy way to determine when the filters being fading. When I first take the new ones out of their packet, I take a set of photos of them on my light box as I did (there was a url link here which no longer exists), then every year I check to see how subsequent photos compare. With my dig*t*l camera I set it to do a custom white balance on the light box - this way it should take into account any changes to the light box's spectral composition over time. Visual comparison or even numeric comparison of the RGB values in an image editor will tell me plenty. Voila a poor man's colour densitometer !

regards
Peter

 

[Martin Aislabie]

Peter, it might not be quite so simple

I found my old MG Filters flared a bit too

So you might need to come up with a cunning flare test too

Martin

 

[PeterB]

I'm using my filters above the lense so flare shouldn't be a problem. Martin can you explain what changes about a MG filter over time to cause it to flare ?
rgds
Peter

 

[Martin Aislabie]

Hi Peter, I'm just guessing about the decay mechanism

I suspect the surface of the filter (gelatine?) starts to microscopicaly flake and becomes uneven - so would scatter light

My old bellow the lens filter set had a slightly milky appearance when compared to the new ones

Because the decay is so gradual its a bit hard to notice - only by holding the old & new filters next to each other were the differences apparent

Also looking at the filter surface at an oblique angle - the new ones were mirror like & shinny but the old ones were more of a semi-matt finish

Sorry, its the best I can do

Martin

 

[scinysnaps]

Peter,
Just got my new filters today..
The #4 was faded compared to the new set,so hopefully the problem is solved!

 

[PeterB]

Yeah, mine arrived yesterday too and my old#4 was really faded. In fact there were sufficient differences between the other numbers too to make me think I had the older style referred to here by Ilford which are "likely to give poor or unpredictable results" anyway !

Soon I'll post photos comparing the two sets.

rgds
Peter