Cheap Folder Lens Tests

I don't typically do "lens tests" and these are actually just the result of film tests to confirm that I had adjusted focus

correctly on these four cameras (all except the Moskva taken at 6ft and the specified aperture, the former at 2m):

 

<img src="http://www.geocities.com/markhahn2000/temp/folder_tests.jpg">

 

I'm going to call the Moskva-5 vs Radionar results a dead heat since the Moskva was shot at f4 and enlarged slightly

more...

though the Radionar seems to have better contrast. Given that the Moskva-5 has a rangefinder, I'm certain that just

for focus accuracy that it will beat the smaller Rolfix in actual usage.<br><br>

 

The uncoated Agfa Anastigmat seems to beat the coated Agnar by a bit, but neither is in the same league as the

other two. Everyone seems to bag on the Agnar and comparitively it seems to deserve this, but I have used that

camera in the past and it did quite decently well stopped down to f11.<br><br>

 

 

The Moskva was stopped down to f4 (from f3.5) to match my flash settings, while the others were shot wide

open.<br><br>

 

 

I went out and actually shot the Moskva today (finally fixed all the light leaks too!!)... so hopefully I'll have something

more interesting to post soon.<br><br>

 

:)

Stop them down to around F/8 and re-run the test. Bet you that all the images improve and the differences become smaller.

I may be missing something here, but it seems to me that you have two different variables that need to be sorted out

in order to make comparisons. One variable is lens quality as expressed in sharpness and contrast. The other

variable is lens collimation, or infinity focus. I don't know how you would sort out the one from the other by just

looking at images from film. It seems like one would first have to establish correct collimation, and then to proceed

with image comparisons. If you use <a href="http://elekm.net/zeiss-ikon/repair/collimate/" target="new">the simple

slr collimation technique</a> illustrated on Mike Elek's site, it takes a lot of the guesswork out of the process

compared to squinting at the image on a ground glass.

No, the lenses were adjusted for infinity focus and these tests were performed at a distance to confirm that the focus was good (the real test was a bunch of staggered cans, ala. Maizenberg), so the focus variable was sorted out to my satisfaction (the whole point of the test)... but in checking the focus from the scanned negatives I realized that I also had a lens test that maybe someone else would be interested in.

 

Same roll of film (Delta 100 in Rodinal), same scanning and processing... it gives a good relative comparison only.

 

I had also commented that the I had used the Isolette before and had gotten good results at f11 (so the point wasn't to say anything was bad or good), but it was nice to see that my until then untested B2 Speedex (which is a more handsome camera) seems a little better... and it was also nice to see how much better the Moskva-5 and Rolfix lenses are, since I am really more interested in shooting them seriously.

I probably shouldn't comment at all on this subject as I have a bias toward skepticism regarding the

transportability and practicality of lens tests. That said, I also think it is pretty important to have

confidence in your equipment, and the kind of systematic examination you've done seems like a good

way to build that confidence.<br>     Your recent thread about the Clack inspired me to

take a closer look at my assumptions about that camera. Since the Clack has a curved film plane, I

used a flexible panel of plastic with some Scotch Magic tape on it to actually examine the image at the

film plane, and I concluded that the actual sharp focus distance at the near setting was about 7 feet,

and the minimum sharp focus at the far setting is around 12 feet. It's a tricky business at small

apertures and somebody else will probably come up with other ideas, but I'm going with that for

now.<br>     Anyway, I hope you'll show us some pictures from that Moskva-5.

Yeah, I probably should have shown more how I tested. I had adjusted the cameras for infinity on ground glass, then

re-checked at 10 ft and then shot a single frame at 6ft:<br><br>

 

<img src="http://www.geocities.com/markhahn2000/temp/rolfix_test_setup.jpg">

<br><br>

This shows how small a section was cropped for the examples.

<br><br>

 

I do think that my test is good enough to show the differences between my cameras/lenses, but not as an absolute

test of any kind.

<br><br>

I'm looking for a Series 6 adaptor so I can shoot the Moskva with one of my hoods... don't know how much I trust the

lens not to flare... but most FSU coatings aren't all that good... but shooting the camera now that I confident it can

perform.

Thanks for checking your Clack and sharing the results! My first test was inconclusive:<br><br>

 

<img src="http://www.geocities.com/markhahn2000/temp/clack_test_close_web.jpg">

<br><br>

 

But this shows the close focus seting and cans lined up from 3.5-5.5ft and it appears that 5.5 ft is about the closest

limit of DOF so my guess was 6.5 ft for actual focus distance (very close to your 7 ft estimate). If the near limit of

DOF for the distance setting is 12 ft, then that should be about 16 ft for the actual focus distance. I guessed that the

lens is about 100mm since I couldn't find any documentation... still narrow DOF at f11. I'm thinking of changing the

aperture for far-sunny and near to be f16 or f22 just to increase the DOF and more optimize the camera for ISO 100

films... though I'm more excited shooting the 6x9 folders at the moment.