Lens Testing: Highest Resolution Developer for Tmax100

[Christiaan Phleger]

Aloha, I'm about to embark on a testing of 3 F2.8 180mm Nikkors, a rebuilt Nikkor P, a ED Ais and a current AF EDIF. I'm going to use Tmax 100, and I have a choice of Rodinal and Xtol. I am experienced in use of both, which would give the highest resolution? Rodinal 1:50, or Xtol 1:0 seem like polar opposites, as in diluted acutance vs surface solvent, but I'm trying to determine max resolution between these lenses. Any other developers I should also consider? Microdol-x? Many thanks and Aloha.

 

[Roger Hicks]

Aloha, I'm about to embark on a testing of 3 F2.8 180mm Nikkors, a rebuilt Nikkor P, a ED Ais and a current AF EDIF. I'm going to use Tmax 100, and I have a choice of Rodinal and Xtol. I am experienced in use of both, which would give the highest resolution? Rodinal 1:50, or Xtol 1:0 seem like polar opposites, as in diluted acutance vs surface solvent, but I'm trying to determine max resolution between these lenses. Any other developers I should also consider? Microdol-x? Many thanks and Aloha.

Regardless of what developer you use, remember that increased exposure and increased development both reduce resolution, so you need to keep both to a minimum when shooting test charts, whereas increased exposure (and sometimes, extra development too) will give superior tonality in a real-world picture.

If you want the maximum possible sharpness I'd go for Delta 100 instead of TMX, and I'd use one of Geoffrey's FX-series acutance developers -- which rather illustrates the fundamental point, which is, what will you learn from developers and films you don't normally use pictorially?

Cheers,

R.

 

[Bromo33333]

Aloha, I'm about to embark on a testing of 3 F2.8 180mm Nikkors, a rebuilt Nikkor P, a ED Ais and a current AF EDIF. I'm going to use Tmax 100, and I have a choice of Rodinal and Xtol. I am experienced in use of both, which would give the highest resolution? Rodinal 1:50, or Xtol 1:0 seem like polar opposites, as in diluted acutance vs surface solvent, but I'm trying to determine max resolution between these lenses. Any other developers I should also consider? Microdol-x? Many thanks and Aloha.

If you are testing a lens, shouldn't you keep everything else the same in the interests of science?

I mean if you changing 2 things (lens AND developer) you will not know if the new developer or the lens is the cause of the change. And if you see no change, how sure are you that the developer didn't cancel out the lens?

I'd do something like this:

TMAX 100 film, 2 rolls, Scenes to be constant, studio preferred due to lighting and subject control. And for lens testing, you will be shooting some stills and test patterns.

Roll1:
1. Series 1: Old lens, Old Chemistry
2. Series 2: New Lens, Old Chemistry
Roll2:
3. Series 3: Old Lens, New Chemistry
4. Series 4: New Lens, New Chemistry

This little design of experiments should be able to separate the effects of the chemistry from the effects of the lens.

Good Luck!

If you know TMAX, then you should stick to that unless you want to re-run the tests in their entirety with another film!

 

[kb244]

...

If you want the maximum possible sharpness I'd go for Delta 100 instead of TMX, and I'd use one of Geoffrey's FX-series acutance developers -- which rather illustrates the fundamental point, which is, what will you learn from developers and films you don't normally use pictorially?
...

I don't know about you, but I never really cared for Delta 100. I've always found that I've received the best results from stuff like PanF+ 50, Fuji Acros 100, Tmax 100, and possibly Ilford FP4+ for currently accessible film. I think the only thing Delta might of had was a strict consistency between rolls, but very very poor push/pull latitude.

But eh what do I know

If you know TMAX, then you should stick to that unless you want to re-run the tests in their entirety with another film!

I concur with this, since if you are developing your own film, you have a good idea what to expect from the film over a period of gained experience. If you start with either a new developer or new film, you'll have to re-learn the norm, and readjust your developing style before you can confidently base any conclusions of lens sharpness.

 

[kb244]

My co-worker says you should be using transparency film, such as Velvia 50 or 100 for testing lens sharpness. Since it would remove most if not all the 'variables', you can also see the color cast of the lens that way as well.

 

[Tom Hoskinson]

Aloha, I'm about to embark on a testing of 3 F2.8 180mm Nikkors, a rebuilt Nikkor P, a ED Ais and a current AF EDIF. I'm going to use Tmax 100, and I have a choice of Rodinal and Xtol. I am experienced in use of both, which would give the highest resolution? Rodinal 1:50, or Xtol 1:0 seem like polar opposites, as in diluted acutance vs surface solvent, but I'm trying to determine max resolution between these lenses. Any other developers I should also consider? Microdol-x? Many thanks and Aloha.

I recommend calibrating your exposure and development process before attempting to do any lens testing. I would contact print an Edmund's Scientific chrome on glass AF resolution chart on the film - . Developed In undiluted Kodak D-76, I would expect both TMax 100 and Delta 100 to resolve in the range of 100 to 130 lines per mm. You will find that exposure and lighting uniformity are critical.

BTW, if you are looking for a acutance developer, I recommend Crawley's FX-2

Kodak Microdol-X is not an acutance developer.

 

[Roger Hicks]

I don't know about you, but I never really cared for Delta 100...

Nor I. But it is probably the sharpest film you can buy, which is the only reason I suggested it. Mind you, I like TMX even less, and Acros less still.

My sole point, really, was this question: what are you testing? If it's the overall effect (sharpness/tonality/grain size & shape/pushability/whatever), stick with the film/dev you like best. If it's resolution, test resolution with the sharpest films and high-acutance developers.

Cheers,

R.

 

[kb244]

Nor I. But it is probably the sharpest film you can buy, which is the only reason I suggested it. Mind you, I like TMX even less, and Acros less still.

My sole point, really, was this question: what are you testing? If it's the overall effect (sharpness/tonality/grain size & shape/pushability/whatever), stick with the film/dev you like best. If it's resolution, test resolution with the sharpest films and high-acutance developers.

Cheers,

R.

In my opinion, if you are testing a lens for sharpness for your own personal use, then its best to stick with whatever the slowest speed film that you would typically use.

Out of curiosity, how are you figuring that Delta 100 is the sharpest you can buy.

Edit Oh and if its for personal use... Don't make this test more complicated than it has to be.

 

[Eric Rose]

I shot some Delta 100 souped in Xtol and I almost cut myself on it. Darn sharp it was!

 

[Gerald Koch]

The film/developer combination that Leica used to illustrate the sharpness of their lenses was ORWO 17 (now Efke ISO 25) developed in Ethol T.E.C. This developer is still available from www.bkaphoto.com. If you are doing this type of testing then you want a fine grain contrasty negative.

 

[sanking]

Aloha, I'm about to embark on a testing of 3 F2.8 180mm Nikkors, a rebuilt Nikkor P, a ED Ais and a current AF EDIF. I'm going to use Tmax 100, and I have a choice of Rodinal and Xtol. I am experienced in use of both, which would give the highest resolution? Rodinal 1:50, or Xtol 1:0 seem like polar opposites, as in diluted acutance vs surface solvent, but I'm trying to determine max resolution between these lenses. Any other developers I should also consider? Microdol-x? Many thanks and Aloha.

In resolution tests using an AF chrome on glass resolution chart with potential of up to 225 lppm I found that PMK 1:2:100 and Pyrocat-HD 1:1:100 gave higher resolution than Xtol 1:2 and D76 1:2 with every film tested, including FP4+, Delta 100, TMX-100, and TMY. For every film exposure was optimized to give the highest possible resolution, and development was optimized to give approximately the same CI.

The differences noted were not great, say 155 lppm for TMAX-100 with the pyro developer versus 130 lppm for Xtol and D76, and might not be of any practical meaning for the type of testing you plan, but nevertheless if you are interested in maximum possible resolution you should consider one of these pyro developers.

Please note that I am not addressing issues such as grain and sharpness here, only *resolution*.

TMAX-100 is a very good film for your testing since its potential in resolution in lppm is very high, around 175 -225 lppm as I recall from Kodak literature, and my tests don't miss this much. Resolution is actually much higher with TMAX-100 than with the slower Pan-F. I don't know the characteristics of the Efke 25 film mentioned.

Sandy King

 

[Kirk Keyes]

Fuji Acros is listed as having a high contrast (1000:1) resolution of 200 lp/mm.

 

[Michel Hardy-Vallée]

You can also get Adox CMS 20 w/ Adotech developer from J&C photo. The resolution of this film is scary: (there was a url link here which no longer exists)

Also, wouldn't a microfilm emulsion developed for high contrast be an even better way of testing lp/mm?

 

[Tom Hoskinson]

I develop Efke 25 and TMX-100 in 1:1:100 Pyrocat-HD. and 1:1:100 Pyrocat-MC The TMX-100 resolution is higher than the Efke 25 resolution at the same CI.

 

[Tom Hoskinson]

You can also get Adox CMS 20 w/ Adotech developer from J&C photo. The resolution of this film is scary: (there was a url link here which no longer exists)

Also, wouldn't a microfilm emulsion developed for high contrast be an even better way of testing lp/mm?

Depends on your goals - i.e, what subjects you intend to photograph and the lighting conditions.

 

[Ed Sukach]

If you are testing a lens, shouldn't you keep everything else the same in the interests of science?

Absolutely correct! In the "Old Days - BMTF*, LENS resolution was determined on an Optical Bench with a proper Resolution Target (that Air Force target was widely used) and a microscope, focusing on the aerial image (a la' Grain Focuser) and nothing else. As soon as film, or a ground glass, or anything else is introduced it becomes SYSTEM resolution.

The system resolution (duplicating something of "real life") may in fact be more coherent for most photographers, but remember that many variables... film, exposure, developer, mechanical misalignments, etc., all have an effect on the results - and cause and effect may be difficult to "sort out".

* "BMTF" = before Modular Transfer Function applications.

 

[Alan Johnson]

Microfilm or ordinary film?
T-max 100 developed in Acutol was formerly used by Amateur Photographer magazine for resolution chart lens tests,the result usually came out at 120-130 lppm max for good lenses.I believe they knew it was film-limited but they said to the effect that it applied to practical situations.
Using Spur Orthopan (believed similar to Adox CMS20) IIRC a new Zeiss rangefinder lens tested at 400lppm on this microfilm but Leica expert Erwin Puts disputed this:www.imx.nl/photosite/technical/bwstateofart.html
If microfilm is used,more lppm will be obtained,but is it realistic? A matter of choice.

 

[Christiaan Phleger]

Wow, and here I thought I'd maybe just get a few responses. Let me clarify some perhaps relevant points.
The lens testing is testing a new aquisition versus two known lenses, not the outside theoretical limits of all the combined optical/mechanical/emulsion/chemical systems.
The Tmax 100 choice is because I had it loaded in the bulk loader, versus my usual Neopan 400 or lots of other choices too numerous to mention in the freezer, and pulling anything out of there would be a time thing due to the de-freezing (quite important out here in Hawaii, RH right now is 70+).
The lens test is already done, all three at the same subject, wide open, one stop down and three stops down, infinity, about 60 ft, 20ft and about 8ft.
The roll is finished and about to be loaded. I have at my easy reach Rodinal and Xtol. Both are developers in regular use, with various emulsions and dilutions, and I'm quite familiar with both. I'd say I'm still learning TMX, relatively speaking. I was looking for the highest resolution between Xtol 1:0 and Rodinal 1:50, and I guess the differences between the acutance and solvent are just two different paths. I'm now leaning towards Xtol unless the Rabid Rodinal's speak now...

 

[Bromo33333]

[...] The Tmax 100 choice is because I had it loaded in the bulk loader, versus my usual Neopan 400 or lots of other choices too numerous to mention in the freezer, [...]

You can use TMAX100, but I would use the film you feel most comfortable making a judgment about.

But anyway - good luck and let us know what you find out!

 

[Tom Hoskinson]

Wow, and here I thought I'd maybe just get a few responses. Let me clarify some perhaps relevant points.
The lens testing is testing a new aquisition versus two known lenses, not the outside theoretical limits of all the combined optical/mechanical/emulsion/chemical systems.
The Tmax 100 choice is because I had it loaded in the bulk loader, versus my usual Neopan 400 or lots of other choices too numerous to mention in the freezer, and pulling anything out of there would be a time thing due to the de-freezing (quite important out here in Hawaii, RH right now is 70+).
The lens test is already done, all three at the same subject, wide open, one stop down and three stops down, infinity, about 60 ft, 20ft and about 8ft.
The roll is finished and about to be loaded. I have at my easy reach Rodinal and Xtol. Both are developers in regular use, with various emulsions and dilutions, and I'm quite familiar with both. I'd say I'm still learning TMX, relatively speaking. I was looking for the highest resolution between Xtol 1:0 and Rodinal 1:50, and I guess the differences between the acutance and solvent are just two different paths. I'm now leaning towards Xtol unless the Rabid Rodinal's speak now...

Rodinal is not a solvent developer, nor is Xtol.

Of course, I would use Pyrocat-MC myself - but if all I had on hand was Rodinal and Xtol, I would go with the Xtol.

Take a look at Kodak's Xtol tech pub: http://www.kodak.com/global/en/prof...9/j109.jhtml?id=0.2.20.14.18.14.7.20.14&lc=en

Xtol Tech Pub Excerpts:

Very high image quality at full emulsion speed.

Fine grain and high sharpness.
Enhanced sharpness, especially with 1:1 dilution.
Enlargeability of negatives 10 percent greater with equivalent sharpness and grain (image quality).

 

[Christiaan Phleger]

As per my original post, the choice was between Rodinal 1:50 (acutance) and Xtol 1:0, which I believe is a solvent developer at that dilution.
No matter, the film's been done and the lenses tested, and some intriguing observations arise. The ED AiS version and the AF EDIF version of the Nikkor 180mm both exhibit a very slight focus shift when used one stop down, wide open and three stops down are precise, and the shift is consistent over medium to long distances. The older, P version does not have this shift. Sharpness among the versions was not an issue, with mostly minor variations. I've done some scans and will figure out how to post.

 

[Christiaan Phleger]

Ok, here goes. Crops are from mostly center. F4, tripod, cable release. Image sharpness is reduced due to more haze than usual for Hawaii, I'm certain that I can squeeze out a sharper image with more fine detail.

 

[Christiaan Phleger]

Here's the full neg image. Sorry, first time posting, still trying to get the sizes right. Scanned from print, no sharpen in PS nor on scanner.