Using grains focuser with or without paper on the easel

[Bill Burk]

DOF at the subject (paper) is a mere 0.016mm in front of the subject and 0.017 behind the subject.

Was this confirmed or found to be a mistake? If it was a mistake what was the DOF found to be?

 

[wiltw]

Was this confirmed or found to be a mistake? If it was a mistake what was the DOF found to be?

Bill, the unit should have been 0.016 'meter', but I erroneously stated it as millimeters.
With correct units, it would be 16mm to one direction from plane of focus.

 

[Bill Burk]

Bill, the unit should have been 0.016 'meter', but I erroneously stated it as millimeters.
With correct units, it would be 16mm to one direction from plane of focus.

Now that makes sense. And we know DOF assumes you are willing to compromise the image at a viewing distance. What kind of “quality” improvement do you get by aiming for tighter circle of confusion?

Suppose we are looking for “practically indistinguishable” when print is viewed at six inches?

This all assumes perfect enlarger parallelism as well, where 1mm error at the negative stage will use most of the paper plane tolerance.

 

[MattKing]

wiltw's numbers relate to the "standard" circle of confusion, which I understand to be associated with 20/60 vision.
Using another calculator and the circle of confusion associated with 20/20 vision, I get DOF of 5mm each way.
In each case, that is in reference to an 8x10 print viewed at one foot.
But more importantly, because of issues of practicality, there really is no way to convert those results into something more demanding, because you aren't able to modify either your visual acuity or the magnification of the grain focuser in any way that will permit you to actually see a difference when you look into the grain focuser.

 

[Adrian Bacon]

I watched that and wasn't surprised. I never put paper under the grain focuser, but am usually printing at at least f8 or f11.

 

[cliveh]

I started watching this video and lost the will to live.

 

[Bill Burk]

I made two claims in my video:
1- That the internet (ie, Photrio) makes this into a multi page argument
2- using paper doesn’t make a difference

Whether you agree with claim 2 or not, claim 1 has been proven true.

Depends what you mean by multi page.

I started watching this video and lost the will to live.

Just close your eyes during the intro

 

[Adrian Bacon]

@MattKing is not saying anyone needs to stop using paper under a grain focuser.

There is a difference between saying there is no demonstrable reason to do something and saying that you should stop doing it.

Anyone here can demonstrate to him or herself whether or not paper/no-paper makes any difference.

Exactly. If you can see a difference (or even if you can't), and you want to do it, go right ahead. If you can't see a difference and/or just don't want to do it, then don't.

Personally, I can't see a difference either way, and I've looked. I don't do it because I don't need to put a sheet of paper down to compose, so putting a sheet of paper down to focus is extra effort for my particular setup. Extra effort for something that I can't see a difference with means I'm not doing it.

 

[faberryman]

I started watching this video and lost the will to live.

Me too. He started hawking that composition tool he sells and I was toast. But, I buckled down and watched the whole thing. It was excruciating. My takeaway is that he says he can’t see a difference. I give more credence to Matt’s mathematical approach. By the way, does he have any clothes on under that apron? If he does, why is he called The Naked Photographer? More importantly, why should I believe some naked guy on YouTube?

 

[Don_ih]

I made two claims in my video:
1- That the internet (ie, Photrio) makes this into a multi page argument
2- using paper doesn’t make a difference

Either my first or second comment was that this is not worth arguing about. There is not even the hint of visible difference looking through a focuser with or without paper under it, but people are going to do it anyway because the base of the focuser should sit at the paper emulsion plane. You cannot dissuade people of things they believe are rationally true. If experience won't do it, math sure won't.

 

[faberryman]

Thank you both for you rude comments about me as though I’m not right here. Very classy.

Don’t take it personally. I would find it excruciating to listen to myself for 15 minutes. The problem with YouTube is that it takes about ten times longer to say something than it does to read the same information on the printed page, so I just don’t have the patience for it.

As to your first point about the internet making this a multi-page argument, it is still quicker to read all five pages of this thread than to listen to your video, and in addition to saving time, I get views from a lot of different people.

 

[Don_ih]

Youtube is for people to get subscribers, get views, make money. The more time passes, the less there is that isn't already beaten to death a hundred times. Most videos are about as informative as a laxative commercial.

 

[wiltw]

Youtube is for people to get subscribers, get views, make money. The more time passes, the less there is that isn't already beaten to death a hundred times. Most videos are about as informative as a laxative commercial.

It's what you get out of 'em that the authors (or drug compnies) care about.

 

[Don_ih]

It's what you get out of them that the authors care about.

That is, ... well, ... naive.

 

[wiltw]

That is, ... well, ... naive.

If you come back to view another YouTube posting, they win. If not, no skin off their back.

When you get something out via laxative, you win.

 

[Sirius Glass]

You do realize how absurd this statement is, don't you?

Of course as are some statements of others.

 

[Sirius Glass]

Heck, if you don't want to put a piece of paper in your easel to focus on, just glue a small piece onto the bottom of your grain focuser and be done with it forever; and be as precise as you possibly can be.

Doremus

But sometimes I use RC paper and other times I use double weight FB paper.

 

[MattKing]

Greg's collection of YouTube videos are excellent. They cover a really wide variety of subjects, and they show people things that they have only read about somewhere, because they have no direct source of in-person experience.
Here is a link to all the links he has posted as Resources here on Photrio (click on the Resources tab):
https://www.photrio.com/forum/members/greg-davis.1392/
If someone asks you for a video reference on a photographic topic, there is a good chance you will find a useful reference among Greg's work.
For those of us who have worked for a significant period of time in a variety of different darkroom situations, the subject of this video may seem boring. Those of us who have a breadth and depth of experience aren't Greg's main intended audience.
But if the only things you know about using a darkroom comes from the internet, then you are bound to run into internet arguments about just this subject. So Greg decided to illustrate the answer to the question.
In an incredible feat of naiveté, I tried to add to the value here by addressing the "why", as well as the importance of understanding the limits of the tools we use, rather than just the simple answer itself. I clearly need to be punished for that sin!

 

[RalphLambrecht]

I guess I am relieved that people are actually using grain focusers instead of just eyeballing it. If you’ve gone to all the trouble of using a grain focuser, why not go whole hog by placing a piece of enlarging paper under it? As long as you are thinking about trying to make your images sharp, you also might want to align your negative carrier and baseboard. For extra credit, you could place a piece of heat absorbing glass between your light source and negative carrier so your negatives don’t buckle. I am sort of picky and use a glass negative carrier.

good man because, that actually makes a difference.

 

[Bill Burk]

Greg! I love your videos. The paper under grain focuser deserves a sequel based on everything new that’s been brought up in this thread.

Ralph! Of course look at things that actually make a difference. Like stopping down “as mentioned in the video”.

 

[radiant]

I think I’ll cover a less controversial topic like “should you pre wet your film or not”.

Do a video on tonality. Just tonality, nothing else.

Or maybe compare Ilfords new multigrade RC deluxe (V) to fiber paper ..

Also video of "is photography art"?

 

[Craig75]

Thank you both for you rude comments about me as though I’m not right here. Very classy.

I like yr videos. Well presented and informative.

Photrio peanut gallery can suck it

 

[Old_Dick]

Craig75, +1

 

[ruilourosa]

Did anyone here read ctein free post exposure?

 

[bdial]

I think I’ll cover a less controversial topic like “should you pre wet your film or not”.

Or, the age-old should I use water or acid stop bath with my film?

FWIW, I thought your test and presentation was excellent.