What kind of filters are these?

[marciofs]

It came with the enlarger when I bought it.

 

[eddie]

Looks like a red filter, to keep the paper from exposure, while the enlarger is on.

 

[Bill Burk]

A red filter is included with many enlargers. It's meant for you to project a safe image on the paper for last-minute composition and focus checking before you make the white light exposure.

Funny thing is, I don't remember the last time I ever used mine - even though I go to some trouble to keep it handy and clean.

It would be useful if you use lightweight easels that move when you put the paper in, but my usual easel is solid and doesn't budge when nudged.

 

[Jim Jones]

In some enlargers, the negative pops after the lamp heats up. One way to avoid this is to leave the light on and use the red filter as a shutter. To prevent enlarger movement while swinging the filter under or away from the lens, hold the other hand under the lens while moving the filter, and control the exposure with that hand.

 

[marciofs]

Thanks,

But why two filter? One is dark read (the square one) and the other lighter red.

 

[480sparky]

For different kinds/brands of paper.

 

[Sirius Glass]

Looks like a red filter, to keep the paper from exposure, while the enlarger is on.

Wot he done did said by gum!

 

[marciofs]

Ok.
Thank you very much again.

 

[andrew.roos]

I find the red filter useful for positioning test strips - I like to have them covering areas of shadow, highlights and the subject.

Andrew

 

[StoneNYC]

I always wondered about the grain focusing part, you do that BEFORE the paper is added, FB is thick, this would seemingly "throw off" the "perfect" grain focus, and the red filter would alleviate this by allowing you to focus once the paper is laid down.

Am I the only one who ever wondered if the focus would be off since the paper wasn't down when you're using the grain focuser?

 

[MattKing]

I always wondered about the grain focusing part, you do that BEFORE the paper is added, FB is thick, this would seemingly "throw off" the "perfect" grain focus, and the red filter would alleviate this by allowing you to focus once the paper is laid down.

Am I the only one who ever wondered if the focus would be off since the paper wasn't down when you're using the grain focuser?

There are long, sometimes acrimonious threads on just this subject.

In essence, the thickness of the paper is well within the depth of focus of the process. If you do the applicable math, you will see that clearly.

The critical distance is the distance between the negative and the principal node of the enlarging lens.

 

[Sirius Glass]

The red filter allows one to get set up for dodging and burning small areas after the basic expose has been done. I would like one of these red filters for my enlarger.

What MattKing said about focus sensitivity to enlarger paper thickness is true, but out of habit and abundance of caution I still put a sheet of enlarging paper under the grain analyzer first. Also my easel have a yellow painted surface which makes it harder to see to align the easel and using a sheet of enlarging paper makes easier to see.

 

[eddie]

There are long, sometimes acrimonious threads on just this subject.

There is a lot of disagreement on this, as Matt states. For me, though, the issue isn't the thickness of the paper. I use fixed out paper to focus on (or dried reject prints) as I find it much easier to see the image against white than against yellow, or gray. I have a much easier time straightening horizons, and seeing what's at the edge of the easel blades.

 

[Bill Burk]

The red filter allows one to get set up for dodging and burning small areas after the basic expose has been done.

That's it!

I knew there was a practical use that made more sense than what I imagined so far. With a red filter you can find/position the hole in the dodger (cardboard with a hole in it) without burning everything around it as you aim.

I don't know why there's two of them, maybe one is built-in and the other was added later.

p.s. I've read the "focus with or without paper threads"... The arguments convinced me that the zone of sharp focus is so deep at the paper easel, that I no longer hunt down a scrap of paper to focus on.

 

[Arklatexian]

The red filter allows one to get set up for dodging and burning small areas after the basic expose has been done. I would like one of these red filters for my enlarger.

What MattKing said about focus sensitivity to enlarger paper thickness is true, but out of habit and abundance of caution I still put a sheet of enlarging paper under the grain analyzer first. Also my easel have a yellow painted surface which makes it harder to see to align the easel and using a sheet of enlarging paper makes easier to see.

The question asked about "filters". I have never seen more than one on an enlarger but this one had two. Why?
I don't really think "for different papers" is the answer but don't know of any other answer.
As for using grain analyzers, I keep a 4x5 piece of whatever photo paper that I am using and put the analyzer on that when focusing. I know people who use the same paper all of the time will actually glue a piece of the paper to the bottom of the analyzer. This works also....Regards

 

[marciofs]

Somebody wrote me and told me that some modern papers have some sencibility to red or maybe some renge of red. If correct each filter could be for diferrent kind of papers.

The deep red is much harder to see the image on the easel than the lighter red which I can see much clearer.

 

[Bill Burk]

It could be as you say, the original equipment old red filter just isn't safe enough with modern papers.

 

[Sirius Glass]

The red filter allows one to get set up for dodging and burning small areas after the basic expose has been done. I would like one of these red filters for my enlarger.

What MattKing said about focus sensitivity to enlarger paper thickness is true, but out of habit and abundance of caution I still put a sheet of enlarging paper under the grain analyzer first. Also my easel have a yellow painted surface which makes it harder to see to align the easel and using a sheet of enlarging paper makes easier to see.

That's it!

I knew there was a practical use that made more sense than what I imagined so far. With a red filter you can find/position the hole in the dodger (cardboard with a hole in it) without burning everything around it as you aim.

I don't know why there's two of them, maybe one is built-in and the other was added later.

p.s. I've read the "focus with or without paper threads"... The arguments convinced me that the zone of sharp focus is so deep at the paper easel, that I no longer hunt down a scrap of paper to focus on.

The question asked about "filters". I have never seen more than one on an enlarger but this one had two. Why?
I don't really think "for different papers" is the answer but don't know of any other answer.
As for using grain analyzers, I keep a 4x5 piece of whatever photo paper that I am using and put the analyzer on that when focusing. I know people who use the same paper all of the time will actually glue a piece of the paper to the bottom of the analyzer. This works also....Regards

You will be glad that you asked about two filters. The reason that there are two filters is for stereo photographs. The problem is just where does one plug in the headset? :devil: My BAD!

 

[AgX]

Am I the only one who ever wondered if the focus would be off since the paper wasn't down when you're using the grain focuser?

If in doubt you always could place the focuser on a appropriate piece of photo paper.


Concerning framing/cropping with the red filter on:
one better use a piece of cardboard inserted in the easel and with the bordering lines for the respective format on it and adjust in plain light.

 

[MartinP]

It is a bit tricky to make out the details of the 'square' filter, but is it possible that it is an additional under-lens filter holder which currently has a red filter in it? This sort of holder/filter is one way of holding multigrade filters (and perhaps colour CC filters too) in the light-path when there is no filter drawer. I use the Ilford Multigrade under-lens filters, both with the supplied filter holder and a homemade foamboard holder on different enlargers.

 

[RalphLambrecht]

Looks like a red filter, to keep the paper from exposure, while the enlarger is on.

true but I find them to be useless.The image is so dimm.One can't see a thing. However, I bought a spare and installed a green and a blue filter into them to try split -grade printing with it. It was a waste of time.Under-the- len-filters worked a lot better.Keep it for resale but ,I doubt you'll ever need it .

 

[marciofs]

It is a bit tricky to make out the details of the 'square' filter, but is it possible that it is an additional under-lens filter holder which currently has a red filter in it? This sort of holder/filter is one way of holding multigrade filters (and perhaps colour CC filters too) in the light-path when there is no filter drawer. I use the Ilford Multigrade under-lens filters, both with the supplied filter holder and a homemade foamboard holder on different enlargers.

I just checked it and the it is a one peace tool. I mean, I can't take the red filter out of the square frame.

 

[marciofs]

true but I find them to be useless.The image is so dimm.One can't see a thing. However, I bought a spare and installed a green and a blue filter into them to try split -grade printing with it. It was a waste of time.Under-the- len-filters worked a lot better.Keep it for resale but ,I doubt you'll ever need it .

This is true for one of the filters that is dark red. The other one that is light red I can see very well the image.

 

[goros]

One thing that none has mentioned is that red light focus at a different plane than white light. Just try to focus with the red filter on and then check without it. You will see the difference. Personally, I focus without the red filter over a discarded paper sheet. I only use the red filter to practice the dodgings.

 

[marciofs]

One thing that none has mentioned is that red light focus at a different plane than white light. Just try to focus with the red filter on and then check without it. You will see the difference. Personally, I focus without the red filter over a discarded paper sheet. I only use the red filter to practice the dodgings.

Thanks Goros.