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Free!... Lens test chart.

mowog
Posted 08/07/2010 - 19:01 Link
1970s Paterson Universal lens testing chart. - Never used.

I bought this a while ago, with the intention of testing all my lenses for sharpness. But quite frankly.... I can't be arsed!

According to the little booklet that comes with it, this chart is primarily used for testing Astigmatism, chromatic aberration and coma (whatever that is) rather than sharpness alone. I think one of the weight or pressure charts from work would make a better chart for sharpness, anyway.

So... Free to any UK based regular, who promises to use it for it's intended purpose.
No man is worth his salt, who has not been banned from at least one Forum, and two Flickr groups.

Mowog.
Algernon
Posted 08/07/2010 - 19:39 Link
I seem to remember there being two versions of this. One was rolled up in a paper tube and the second came as a folder with loose A4 sheets.

The second version had to be brought out because a lot of lenses were off the chart on the first version.

It is a resolution test chart and is the one that AP have always used. I think they have a PDF (scaled down version) for download on their site.

I've only ever used it once on digital it seemed to work OK, but the lpmm test is meant to be carried out on slow film.
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
mowog
Posted 08/07/2010 - 22:13 Link
Yes, I think there were a few versions. This one folds out to about 30 inches by 20. You pin it to a wall and photograph it at a distance, depending on the lens focal length. 4 feet 4 inches for a 50mm, and 11 feet 4 inches for a 135mm, for example.
No man is worth his salt, who has not been banned from at least one Forum, and two Flickr groups.

Mowog.
Algernon
Posted 09/07/2010 - 11:49 Link
That's 27x focal length. The later chart was 40x . If I were using that chart I'd try it at 50% more than stated = 6ft 6in and add 50% to the lpmm results otherwise everything will be resolved
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
paulgee20
Posted 10/07/2010 - 13:50 Link
Hi MO

If you still have this chaart i will put it to good use.


Paul
K5's (2)both gripped, K10d gripped, Pentax 28-90 f3.5, Sigma 18-250mm, Sigma 150-500mm. Sigma 105mm f/2.8 EX DG Macro, Sigma 10-20 f.4-5.6.EX DC, Hoya 135 f2.8, Take on 28mm f2.8 Pentax AF360 flash, 2 fill in slaves. 30 metre remote release, Rt angle viewfinder, Giotto NOT 3261B Tripod with Manfrotto 808Rd4 ball head, Manfroto 4861RC2 monopoly, shoulder stock, various filters etc, Panasonic SET HBS HD Video cam, Tamrac Explorer 8x backpack and a sore back.....
-------------------------------------------------------
Photography is an index for measuring futility and pride.......

Paul

:wink
http://s743.photobucket.com/home/pg20_photos/index https://www.flickr.com/photos/pg20
mowog
Posted 10/07/2010 - 14:11 Link
It's yours, Paul.

PM your details.
No man is worth his salt, who has not been banned from at least one Forum, and two Flickr groups.

Mowog.

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