Low tech lens testing suggestions

[weasel]

I have ended ups with 4 different LTM 50mm lenses; a 3.5 Elmar, a 1.9 Canon Serenar, a 1.5 Canon Serenar, and a j8 that has been adjusted to focus on Leica. I have shout all if these lenses, and while they do have different character, I would like to do something a bit more systematic to compare their performance.
I have no digital body to put them on.
What low tech methods do you all suggest?

 

[Alan Johnson]

I have used print outs of the 2.5mm 2003 Koren Chart. Skip all the MTF stuff and it is possible to estimate lppm resolution.
If lppm resolution is not needed just photograph the chart on film from the same distance with all lenses and compare results by your chosen method.

Lens testing

 

[weasel]

thank you for this

 

[Ardpatrick]

I vaguely recall that lens testing at 50x the focal length was preferential. So with a 50mm lens that would be 2.5 meters. Alignment is important and ideally use flash for illumination to avoid issues with camera shake.

 

[Korbel]

The simplest way is to shine light through them with a phone light or flash light and check for scretches, dust, fungi and other defects. You will certainly not find pristine glass in vintage lenses, but minor defects don't imo affect the performance in most cases and if they do it is noticable mainly when photographing against a light source

For a more rigorous testing I was thinking of making a DIY projector, but that would be quite complicated since you need the light to be parallel (I think because thats what the lens does)

 

[RalphLambrecht]

I vaguely recall that lens testing at 50x the focal length was preferential. So with a 50mm lens that would be 2.5 meters. Alignment is important and ideally use flash for illumination to avoid issues with camera shake.

good advice. Photographing a 1951 USAF chart at 100x focal distance will give lp/mm, but that number by itself won't tell you much. Creating an MTF tells you more, but its creation is complex.