Lens testing procedure USAF test CHART

[redstarjedi]

I intend to shoot a USAF test chart, following the methodology in the link below. I don't understand step 7, where i determine the distance of the chart from the lens using a formula. I will be using a contax G2 and 45mm lens.


Dead Link Removed

 

[Theo Sulphate]

With a 45mm lens, position the tripod and camera so that the front lens element is (55x45mm) away from the chart. That is 2475mm or <edit: error deleted>

Ensure the camera is parallel to the wall and chart.

Best to use a cable release to trip the shutter (or the self timer if the release isn't threaded).

 

[albada]

With a 45mm lens, position the tripod and camera so that the front lens element is (55x45mm) away from the chart. That is 2475mm or roughly 9 and 3/4 inches.

I get 8 feet plus 1.4 inches.

Mark Overton

 

[shutterfinger]

1 inch=25.4mm; 45*55=2475/25.4=97.44 inch=8 feet, 1.44 inch; 7/16=.4375
Distance should be 8 feet 1 7/16 inch.

 

[RalphLambrecht]

I intend to shoot a USAF test chart, following the methodology in the link below. I don't understand step 7, where i determine the distance of the chart from the lens using a formula. I will be using a contax G2 and 45mm lens.


Dead Link Removed

maybe this helps

 

[Theo Sulphate]

I get 8 feet plus 1.4 inches.

Distance should be 8 feet 1 7/16 inch.

Correct. My error.

 

[Dan Fromm]

Interesting. My copy of Edmund 83001 has instructions printed on it. They recommend positioning the camera 10 focal lengths from the target.

 

[Paul Howell]

Don't know why you are following the procedures listed, all you will be doing is comparing your Zeiss lens to Pentax lens, your 45mm will out resolve Kodakcolor 100, if you still find a roll, for matter it will out resolve TMAXX 100 200 L/MM or Ektar 100.

 

[RalphLambrecht]

Interesting. My copy of Edmund 83001 has instructions printed on it. They recommend positioning the camera 10 focal lengths from the target.

that is correct the distance should be a multiple of the focal length.this way you can use it as a multiplier for the resolution result.

 

[Les Sarile]

I intend to shoot a USAF test chart, following the methodology in the link below. I don't understand step 7, where i determine the distance of the chart from the lens using a formula. I will be using a contax G2 and 45mm lens.

Is it your intention to match up to their results?

If so, you won't find anymore Kodak Royal Gold 100.
Which of course brings up the next question on whether or not it is the film or the lens limiting the results?

 

[Paul Howell]

The site OP is following appears to be dedicated to Pentax lens, he will get a result to match his Zeiss 45 to a verity of Pentax normal lens, I think Ultrafine still has in date Kodacolor 100. In the old days, Modern and Popular Photography use slow black and white, including microfilm to test lens. I last tested a brace of 50mm I had with the last of my Adox Microfilm, I tested Pentax M42 and K mount, Yasicha, Mamyia, Konica, and Miranda, one lone Minolta MD, all exceeded 200 L/MM.

 

[Les Sarile]

I last tested a brace of 50mm I had with the last of my Adox Microfilm, I tested Pentax M42 and K mount, Yasicha, Mamyia, Konica, and Miranda, one lone Minolta MD, all exceeded 200 L/MM.

Do you have these available?

 

[Paul Howell]

I need to hunt them down, as I live in a smallish townhouse I had to put several boxes in storage, may take a few days to see what I have on hand. What I recall is that at F 8 all exceeded Tmax 100, some were better wide, the Konica 57 1.7 and Miranda 50 1.9 and 1.4 and Kowa F 2 on fixed lens RE were excellent as was the Pentax M42 and K, the others were a little soft wide or had some barrel distortion wide or at F16, but had to really look for it, in day to day operations not enough difference to worry about. I did not test Nikon or Canon or any German lens.

 

[Les Sarile]

I tested Pentax M42 and K mount, Yasicha, Mamyia, Konica, and Miranda, one lone Minolta MD, all exceeded 200 L/MM.

I was also curious about the performance of my bought used manual focus lenses so I use 12233 rescharts 1200dpi laser printed on tabloid size paper arranged in 4 X 4 using Kodak Techpan shot at ISO25 and processed in Kodak Technidol. I then examined the results and found that all my primes will not be the lowest common denominator when it comes to capturing details.

For instance I have found that my Pentax M 50mm f4 macro lens never failed to deliver sharp results so I tested it and show one of the results below. Bottom left is the full target of 4 X 4 test charts. Above it are the 100% crops of the center of the target using a 14.6MP Pentax K20D + autobellows, Coolscan 5000 4000dpi and 36.3MP Nikon D800 + autobellows. To the right is about a 4.5X optical zoom of the center area and you can clearly see that there is quite a bit of detail unresolved.

Full res version -> http://www.fototime.com/8372250EA44CB06/orig.jpg

At this point I am not sure what is the limiting factor - test target, film, lens or a combination of factors?
But one thing I am sure of - even though the lens was bought used, it is not the weak link!

 

[craigclu]

Here's the old Modern Photography procedure, using the USAF targets. It may have some points to ponder and was part of a discussion awhile back:

[URL="https://www.photrio.com/forum/index.php?threads/resolution-chart-targets.67576/page-2#post-953334"]Resolution Chart/Targets[/URL]

 

[dynachrome]

Somewhere I have an old Modern Photography issue with tests of standard lenses. The highest resolution results were obtained by the old Kodak 5069 High Contrast Copy film. It had even higher resolution that Technical Pan. I have plenty of Tech Pan and ImageLink HQ on hand as well as a supply of 5069 in 35mm size as well as two different kinds of ImageLink in 120 size, cut down from 105mm wide stock. When a lens for 35mm film is being tested, you can get a good idea of what's possible without resorting to microfilms. If you really need a large print of a particular subject it is often easier to just use a larger format.

 

[Les Sarile]

Here's the old Modern Photography procedure, using the USAF targets. It may have some points to ponder and was part of a discussion awhile back:

Panatomic-X 400 film?
I wonder if theyr used viewfinder magnifiers?
I use a 40X microscope.

 

[Les Sarile]

The highest resolution results were obtained by the old Kodak 5069 High Contrast Copy film. It had even higher resolution that Technical Pan. I have plenty of Tech Pan and ImageLink HQ on hand as well as a supply of 5069 in 35mm size as well as two different kinds of ImageLink in 120 size, cut down from 105mm wide stock.

Of course now we have to have an index of the various films used to correlate results.

 

[Alan Johnson]

https://www.photrio.com/forum/index.php?threads/very-high-resolution-lens.52581/#post-768495
See esp post 10 by Henning Serger. I believe he carries out tests for a European publication.

 

[Theo Sulphate]

For Tech Pan in Technidol, what is the resolution in lp/mm? How does that compare with Adox CMS 20 II?

My 16x20 medium format prints from Tech Pan have astounding resolution (taken with Zeiss 50/4 CF FLE lens).

 

[Paul Howell]

This seems right, How high was the resolution of high contrast copy? Tmax 100 has better resolution than Techpan. I think Ultrafine sells ortho film in 35mm loads, I'll check to see if Ultrafine's web site lists the resolution. I have a number of charts, the USAF, along with a chart from Modern Photo and a recent chart I use for color.

 

[redstarjedi]

My goal is to take a sharp as possible slide of the test chart, and use that positive to scan on my noritusu LS-600 and use it as a guide to custom focus my scanner.

More on this scanner, below and their try and guess method to focus the scanner. Hence my desire to use high resolving lens and film
http://www.gostreetphoto.com/noritsu-ls-600-film-scanner-review/

 

[Les Sarile]

This seems right, How high was the resolution of high contrast copy? Tmax 100 has better resolution than Techpan. I think Ultrafine sells ortho film in 35mm loads, I'll check to see if Ultrafine's web site lists the resolution. I have a number of charts, the USAF, along with a chart from Modern Photo and a recent chart I use for color.

I also tested TMAX 100 and Fuji Velvia the same way I tested with Techpan and will follow up with the results too.

 

[RalphLambrecht]

The site OP is following appears to be dedicated to Pentax lens, he will get a result to match his Zeiss 45 to a verity of Pentax normal lens, I think Ultrafine still has in date Kodacolor 100. In the old days, Modern and Popular Photography use slow black and white, including microfilm to test lens. I last tested a brace of 50mm I had with the last of my Adox Microfilm, I tested Pentax M42 and K mount, Yasicha, Mamyia, Konica, and Miranda, one lone Minolta MD, all exceeded 200 L/MM.

do you mean lp/mm?

 

[Paul Howell]

do you mean lp/mm?

yes LP/MM