On 7/12/2018 7:50 AM, Jan Steinman wrote:
From: Moose <olymoose@xxxxxxxxx>
I suspect this test is so compromised by these factors as to be useless in
evaluating differences between the lenses.
Don't you think this is a bit harsh?
I tried to think of another way to say it, but for me, not necessarily for anyone else, I could see no way I would
decide what lens to buy or not to use or buy from those pics. Honesty not the best policy?
Did I hurt your feelings by dissing the mighty Soligor 180/3.5?
I've never owned, or wanted to own, a Soligor. I devoured tests back when. Tamrons, Tokinas, Kirons, some Vivitars and
the occasional Sigma seemed to be the first tier, below/beside camera makers own lenses. Soligors seemed to be in the
swamp below.
So, OK, the Soligor was a dog, I didn't need the test to tell me I didn't want one. OTOH, many folks here and elsewhere
and published tests said that the Tamron 300/2.8 was a better lens than the Oly 300/4.5. So it seems most likely to me
that you had a bad example.
Did the wind or subject motion cause all that flare? :-)
I didn't pay attention to flare. I did notice some vignetting, but , like low contrast on some mirrors, that doesn't
matter any more, in the digital darkroom.
I agree with most of your criticisms, but I never claimed it was a definitive
test. More like an interesting data point.
There's one thing you can say about "the other" IQ tests: they select for
people who are good at taking IQ tests!
Certainly true; heaven knows I've known my share of high IQ people without, as my dad* used to say, "the sense God gave
a grasshopper". OTOH, if I want a person to do that kind of thinking, or a lens to capture fine detail, I look at the IQ
tests.
I had a job where I needed people who could both deal with all kind of people around NA, then do numbers analytical work
in the office. Without a certain minimum thinking ability of the kind measured by IQ tests, they couldn't do the
analysis. Without what Daniel Goleman called "EQ", they couldn't do the field work. Without common sense, or whatever it
is, they couldn't tell when the numbers weren't working.
I think the same is true of lens Image Quality tests. Pictures of test charts
bore me. If I want a copy stand lens, I'll pay attention to the chart photos...
and probably grab the Zuiko 28/2.
I had a 28/2 at the time I did a LOT of copying, making slides for a friend teaching art at UC. OM 50/3.5 and Tammy
90/2.5 did a wonderful job. (Tungsten slide film, continuous light, again, to avoid reflections off the varied source
material and occasional glass cover.)
But I don't do much of that these days. Give me something real to look at!
Yea, there may have been some air motion and subject motion going on. And the
600/6.5 that did so well in that test has consistently let me down since. But
the 500/8 Reflex continues to amaze me.
So you might agree - ish with me about this test for that lens? :-)
I did get rid of the Tamron 300 shortly afterward, but also got rid of a Zuiko
350 that left me consistently unimpressed.
It's still nigh impossible to make a crappy lens perform under difficult
conditions, while a good lens might be able to.
Agreed
And there's also sample variation to consider, as well as usability issues.
Certainly so. You may have noticed how careful I was in making a conclusion about Panny 10-300 vs. Oly 75-300. And the
mirror lenses are only usable under limited circumstances. That doughnut bokeh isn't nice, and the 1000/11 is a pain to
set up and use.
Just for fun, I included a beat up Tamron SP 500/8 that I acquired somehow/where. No doubt about it, it's junk, compared
to my pristine OM 500/8. But reading the old Modern Photo tests, they should be roughly equal in resolution, new, with
the Oly having much better contrast.
A friend rented a PLeica 12/1.4 to shoot aurorae in the far north, liked it, and bought one. After good, but not
outstanding results, sending it to Panny, who said it was fine, and checking with an independent tech, he bought the one
he had rented and sold the other one. Yes, he's a (now happy) fussy pro who makes a living at photography, but sample
variation is very real.
And don't even talk to me about 1:40 ratios for testing.
The charts are indeed boring, and yet, they can separate pure optical resolution performance that may be unclear in
field photos. Someone said "It's still nigh impossible to make a crappy lens perform under difficult conditions, while a
good lens might be able to.", and that's one way to be sure to have a good one on hand for the difficult conditions.
Not long ago, I set up in my driveway, and took a series of photos of the house and yard across the street and the trees
behind. Things moved, the light changed over that time. I learned what I needed to about several lenses and FLs, but it
was a pain. In particular, the Panny 12-60/3.5-5.6 was returned and I kept looking for a replacement for the Oly 12-50.
When the PLeica 12-60/2.8-4.0 came out, I did my testing indoors. Much easier to see IQ differences. It's ended up being
a big favorite of mine.
How many real-world subjects are shot at exactly 1:40?
Uh, the Meade 1000/11 in this test of mine. BTW, The air movement video I posted was taken with it. The still was poor,
worse than I know this lens can do, so won't see the light of day. Maybe on a cool, still, winter day? It did quite well
on a Super Moon.
It's an arbitrary number, is all.
Not logically so. At least back then, non-macro lens optical designs were optimized not for infinity, but for 1:40, so
it made sense to bench test at 1:40 and include sample shots of real stuff.
Bottom line: I hope nobody went out and bought or sold a lens based on my humble eagle
photos, but I also think this series was not entirely without merit. It answered the
question, "Under these conditions, which of these lenses would you consider
grabbing?"
Ah, well, I already know the answer to that, among the lenses I have. I also know what to do with it, take lots of
shots. In this test, the 100-400 @400 result was slightly off (remember, I've taken many thousands of shots with this
lens at that FL). Close inspection reveals it was slight back focused. Likely operator error in setting the AF point,
not using MF and magnification. But I also know that, at those FLs, with that lens and my cameras, slightly missed focus
with ridiculously shallow DoF is common, so I bracket in the field.
[If I bracket, the first shot is usually the best. If not, the only shot isn't
great. What's that about?]
To me, the biggest surprise of this test was that certain shorter lenses
CONSISTENTLY out-performed longer ones, even after cropping to achieve a
similar subject size.
This may drive you crazy. In astronomy, telescope lens/mirror size interacts with average air cell size. This is one
reason that the Questars have always competed well with larger 'scopes. Absent tests conducted in still, indoor air, I
can't tell whether that effect is in the optics, in the air or what the combination may be. I do know that in my 1:40,
indoor tests, I don't see that, but - no Soligors*, etc.
For the Super Moon, I intended to take several shots and combine them. When I overlaid them in layers, I found that
whole sections of the surface were in different places in different shots. I had to make do with one.
<http://galleries.moosemystic.net/MooseFoto/index.php?gallery=Lunacy&image=_MG_6617croof2n.jpg>
Combine some clear, evening desert air, whatever that means for cell size, with the 100-400, and the results aren't bad!
<http://galleries.moosemystic.net/MooseFoto/index.php?gallery=Lunacy&image=_B008015fp.jpg>
Moose d'Charts
* Phi Beta Kappa PhD from Berkeley.
** Poor Soligors! Not good enough for my conventional photography, too good for the
"Alt" work. :-)
Like Vivitar, Soligor was a marketing name for lenses sourced from different
makers.
--
What if the Hokey Pokey *IS* what it's all about?
--
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