Paper sharpness

[Eric Rose]

I hope this hasn't been beat to death already, but I was wondering which B&W paper is considered the "sharpest" when used with an enlarger. Not talking about contact printing or litho stuff here, just what paper appears to be the sharpest. I would suppose edge effect etc might play into this, but I'm not sure. It seems silly to spend all this time, money and effort on getting razor sharp images on the neg and then getting less than optimal sharpness in the print. Again not counting the enlarging lens, shaking enlarger and such.

Thanks for your help.

Eric

 

[David A. Goldfarb]

There's this theory that graded papers are sharper than VC papers. It may be true, but it could depend on various factors other than the paper, like the light source and filtration.

My theory on this is that VC papers have a wider spectral response than graded papers (otherwise the filtration wouldn't work), so they will show up chromatic aberration in the lens more than graded papers, depending on the filtration, the lens, and the light source. If you use an apochromatic lens or a narrower band light source or a strong monochromatic filter, you shouldn't have a serious problem with chromatic aberration, so you might not notice a difference under those circumstances.

 

[Ed Sukach]

</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (David A. Goldfarb @ Feb 5 2003, 02:19 PM)</td></tr><tr><td id='QUOTE'>
My theory on this is that VC papers have a wider spectral response than graded papers (otherwise the filtration wouldn't work), so they will show up chromatic aberration in the lens more than graded papers, depending on the filtration, the lens, and the light source.&nbsp; If you use an apochromatic lens or a narrower band light source or a strong monochromatic filter, you shouldn't have a serious problem with chromatic aberration, so you might not notice a difference under those circumstances.</td></tr></table><span class='postcolor'>
Chromatic abberation as an error in a lens system affects black and white media nearly equally as severly as color media.

The Spectral sensitivity of "Graded" (non-variable contrast) paper is not restricted to a narrow spectral band ... and few enlarger light sources (actually, none that I know of ) are to any great degree monochromatic. Chromatic abberation is caused by a lens design that focuses different wavelengths of light to converge to differing points ... and the worst case of that I ever encountered was in a Kodak Contour Projector - where the edge of a silhoette projected to the exteremes of its 30" screen were red on one side and blue on the other. Another Comparator manufacturer (Jones and Lamson) offered a monochromatic light source - a mercury vapor lamp - to avoid just that effect.

Enlarging lenses -- every one that I've ever been in contact with - seem to have *very* little chromatic abberation - as a design criteria.


a defect

 

[SteveGangi]

Taking a different tack, to at least give the impression of greater sharpness, you probably would want to use a glossy paper. Apparently, any sort of texture will look a bit softer (but for portraits that would be good). The downside is that glossies have an "issue" with glare or reflections when viewed. To give the standard non-answer, our eyes can only resolve so far and anything more is gilding the lily. To further confuse things, higher contrast and colder tone can sometimes make a print look sharper, at least to some people.

 

[lee]

I have always used glossy paper because I just like the way it looks. I dry prints on fiberglass screens and they then have lost some of the "glossy". I am always amazed how good images dried that way look when matted and placed behing glass. It might just be personal preferance.

lee\c

 

[Thilo Schmid]

Eric,

sharpness is often a synonym for “detail contrast”. Sharpness is more often related to paper grades than to paper quality aspects. However, the surfaces of the paper and the viewing conditions (e.g. glass frames) have an impact on visual contrast, too. All modern papers have a resolution power far beyond what the lens will deliver.

 

[Donald Miller]

I know that this thread started with the caveat of no litho. But if one is attempting to gain the greatest impression of sharpness in a print then unsharp masking procedures are a definite boon to the impression of sharpness.

There are two factors involved with this impression of sharpness. The first is that there are edge effects that come into play. The second factor is that by using an unsharp mask the overall contrast of the camera negative is reduced. This reduction of the contrast level in the camera negative is offset by using a higher grade paper (either VC or graded paper). This increase in paper contrast brings into effect greater local contrast. This greater local contrast then brings about an impression of much greater sharpness into the print.

The procedure of unsharp masking is fairly simple and straightforward, as far as masking procedures are concerned. All that is required is some really inexpensive litho film and diffusion material.

Insofar as paper sharpness in and of itself, I think that in my experience, the effects of spectral diffusion are non apparent. One can not create any portion of the visual spectrum that does not already exist. In other words you can not create UV from either the visual or the IR spectrum. Todays papers have very well defined response sensitivities. So aside from possible flare (which is another matter in and of itself), it would seem that papers will only respond to the portion of the visual spectrum to which they are sensitive.

 

[Eric Rose]

Do they publish lines per mm ratings for paper?

 

[Donald Miller]

While I can not speak to all papers, I have never encountered a published criteria by any paper manufacturer that addressed "lines per mm". Most of the technical publications related to a given paper address matters such as spectral sensitivity, paper speed, and characteristic curves. I think that the resolving power of the paper is actually a stronger link then some of the factors contributing to the image such as lenses-both taking and enlarging, film and developer choice, and other factors such as flare. It is the last link in the chain and while an important link, every other factor which could be detrimental to the image prior to the printing is amplified in the printing process.

 

[Eric Rose]

I have emailed Ilford and asked them if they have any data they can share with us on the "sharpness" of their papers. If and when they reply I will share it with the group.

I won't hold my breath however.

 

[David A. Goldfarb]

They're actually pretty good about replying, though who knows whether they've actually tested papers for sharpness. If you hear from David Carper, make sure he knows about apug.org. He follows some of the online forums.

 

[Eric Rose]

Thanks David. I actually made sure I mentioned apug in my email. I was hoping they would check us out.

Eric

 

[RAP]

Some papers have a little more surface texture then others that can effect the impression of sharpness. I think Ilford Gallerie has the most. The sharpest paper I have ever used was the now discontinued Zone VI graded papers. Very little suface texture. It was a great paper. Now I think the best paper on the market is Oriental Seagull graded papers. Deep rich tones with excellant toning abilities. I do not use VC papers. They seem to lack the ability to give a real deep night sky like black that you can really look into. I have never seen any of Ansel Adams books where he printed on VC papers. Though in his darkrrom book, he has a photo of an old style VC head.

 

[GreyWolf]

Hi Eric,

re: "Do they publish lines per mm ratings for paper? "

I read that in order for an 8 x 10 print to be perfectly sharp we need to have 30 lp/mm. If the print has as few as 5 lp/mm it would be considered generally sharp for the casual viewer. Most of us probably like something in the middle and strive for closer to 30 lp/mm for perfect viewing pleasure.

To get that type of resolution at the 8x10 print level you need to get 200 lp/mm or more in a 35mm format. Hard to do. In a 4x5 format you'll need about 60 lp/mm in your neg which is quite possible and frequently achieved.

Color negative paper can achieve about 65 lp/mm and most quality B&W papers can easily go as far as 125 lp/mm. Even though all B&W papers are not equal, even with an average paper used correctly can easily reach 60 lp/mm , which is double the requirement to get crystal sharp prints.

If you are really interested in improving sharpness during the printing stage (aside from a very good negative, which is another topic) then your enlarger lens is the single most important element to consider.

The single simple thing that anybody should do is ensuring that your enlarger is properly aligned. The cost is only time and the improvement (if misaligned) is usually quite evident and a quick reward.

Hope this might help with your question. Sometimes folks seem to claim that one paper is sharper than another but I believe this is mostly due to other factors like acutance (perceived from the paper surface) and different contrast grading from manufacture to manufacture.

 

[Eric Rose]

Wow great reply GreyWolf! While I have been fairly happy with the sharpness of my prints, I am wondering if somehow I couldn't make it better. I know that I need to align my new enlarger. Time to get out the laser and mirrors! Oh and some bubble levels too. I would like to test out another 210 or 150 LF lens against mine to see if I can see any difference in neg sharpness. I can't wait to try out my new Rodagon 150, but have had a bit of a challenge getting it to fit to the enlarger lens turret. Maybe tomorrow night.

In another post on this board, and PN too, I have asked for some advice on adjusting my color head laterally. Still no replies so I guess I'm on my own. Since the move I can't find any of my tools so should be fun.

Good to hear from you again.

 

[David Hall]

Since I have been using Azo, I have noticed that the paper actually does seem significantly sharper than enlarging papers. And I don't mean maybe sharper, or sharper with a certain kind of print in a certain kind of light. I mean that when I compare my azo contacts to contacts done on enlarging paper, the azo really looks a whole lot sharper.

Why? I assume it's some kind of optical illusion. Is it because the blacks are much blacker? Local contrast greater? Some kind of edge effects?

dgh

 

[Donald Miller]

David, I concur with your experience using Azo. With Amidol, it is wonderful stuff. The best that I have used. The Amidol is pricey but the quality keeps me coming back.

 

[avandesande]

</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (dnmilikan @ Feb 20 2003, 05:19 AM)</td></tr><tr><td id='QUOTE'> David, I concur with your experience using Azo. With Amidol, it is wonderful stuff. The best that I have used. The Amidol is pricey but the quality keeps me coming back. </td></tr></table><span class='postcolor'>
The way Michael Smith describes it is that the development occurs on the very top of the emulsion (using amidol). Perhaps the extreme thinness of the silver layer contributes to the percieved sharpness.

 

[David Hall]

Maybe. There is also a depth that is more pronounced than with enlarging papers. I have NO idea how that happens. But I know that when looking at a well printed Azo print, the thing looks like it's three feet deep. I have noticed this with Azo and other developers too, like Ilfobrom and Neutol WA, but it is clearly the most obvious with Amidol.

dgh

 

[Ole]

Resurrecting old threads again...

I've been using a lot of different papers lately, including some very old and rare ones. In most cases the visible differences are in the tonality, and "feel", not sharpness. I have tried all the papers by enlarging the same 4x5" negative to 8x10", so the only difference is the paper.

There is, however, one exception: Ilfospeed G3, matte. This paper (bought around 1985) is visibly and obviously sharper than anything else I've tried. Looking at the print with a 20x loupe, the only "softness" I could see came from the negative (confirmed by checking the negative at 60x and 400x under a microscope).

Thinking that the higher contrast (compared to the other graded papers) could have caused higher apparent sharpness, I dug deep in the drawer and pulled out an ancient pack of Agfa Brovira grade 4. The Ilfospeed was still sharper.

Unfortunately I do not own this paper in any other surface than matte, or any other grade than 3. But I will try to get hold of some more.[/b]

 

[Jim Chinn]

As has been pointed out, there are a lot of variables to check before worrying about the paper. Quality of lens and coverage for the format, enlarger alignment and possible vibrations in the enlarger or table, the flatness of the negative during printing, the easel being used and is it holding the paper flat. After all those variables are controlled you could evaluate various papers keeping in mind that apparent sharpness is more important than LPM and needs to be evaluated with regard to the size of the print and the viewing distance.

Finally, you may find that your favorite paper may resolve less then other papers, but those papers produce inferior tonality or range for your application. If you are working with 4x5 and larger, you may want to explore unsharp masking techniques which do not actually produce a sharper image but do produce more apparent sharpness through control of local "micro"
contrast.

And of course one can eliminate several of the variables by contact printing.

 

[fhovie]

I have found that condenser enlargers make prints that appear sharper then diffusion enlargers. I also find that high accutance negative developers enhance the appearance of sharpness - As fas as paper goes - The sharpest looking images usually seem to be on contrasty ferrotyped FB or glossy RC papers although I find un-ferrotyped glossy FB and mat FB to be more desireable overall. It think the appearance of sharpness has less to do with lpm and more to do with grain and accutance. Tri-x has a gritty grain that looks very sharp although when developed in D76 doess't break any records for resolution. Tech pan may have the greatest resolution but may not always look sharp.

 

[Ole]

The sharpest looking images usually seem to be on contrasty ferrotyped FB or glossy RC papers although I find un-ferrotyped glossy FB and mat FB to be more desireable overall.

That's what I thought too, until I got out the microscope to check my first impression. Ilfospeed G3 RC mat really is sharper than anything else I've tried!

 

[Lex Jenkins]

The main factor I see in apparent sharpness of paper is related to the grain of the substrate (not the silver halide grain but the actual formation of the paper base, the "pores" for lack of a better term).

I was nattering about this with Lee over coffee the other day, specifically in relation to the Eliot Porter show earlier this year at the Amon Carter (which received the bulk of his estate).

What struck me about Porter's 8x10s (from 4x5 negs) wasn't a matter of extreme sharpness. It was the color - and I don't mean "bowl you over and assault your eyeballs" color. Just the natural, subtle and faithful color.

As for apparent sharpness, I didn't see anything that couldn't have been duplicated with medium format and possibly even 35mm.

WHAT! Heresy!!

Hear me out...

Below a certain size the grain of the paper interferes with fine resolution. For example, we were looking at a print in the 5x7 range from one of Don Miller's 4x5 negs. I was certain that if I'd had a loupe handy I could have read the name on the mailbox. I was also certain that name would appear to dip and rise with the grain of the paper. However, in an 8x10 or even larger print the name on that mailbox would actually *appear* sharper because with enlargement the paper grain becomes less a factor - it doesn't increase in proportion to the print size. Paper grain remains of a relatively fixed size, tho' this varies of course.

So up to a point we should be printing at a certain ideal (yet undetermined by me) size that would overcome the grain pores of the paper, yet would not exceed the limits of the negative.

Make sense? If not, feel free to dig in. This is just my pet theory backed up by nothing more than personal observations.

 

[fhovie]

I think you hit the nail on the head Lex - Apparent sharpness requires some grain. There are ideal formats/film-types/developers that will have a favorite print size for sharpness. I find that for what I do in 35mm looks great in a 5x7 and good in a 8x10 and then after that it is too grainy for my taste for most of the images I make - for 6x6 it is great in a 8x10 - good in a 11x14 and often acceptable at 16x20. But this is all considering the film and developer choice. Pyro makes bigger grain than Microdol no matter how masking the stain is and that sets up the enlargability of the negative -
Of course 4x5 negatives always print good! g

So up to a point we should be printing at a certain ideal (yet undetermined by me) size that would overcome the grain pores of the paper, yet would not exceed the limits of the negative.

Make sense? If not, feel free to dig in. This is just my pet theory backed up by nothing more than personal observations.