I braved the heat today and only lasted 30 minutes before i came in soaked with sweat.
Weatherman said St Pete Fl would feel like 110 with the humidity today!
DavidBM wrote:
Mea culpa! I was going to do a comparative review of 1:1 lenses The phillipreeve.net site, but ended up concluding that I really needed an etched glass resolution target that could be used in a slide holder to get a repeatable target that is guaranteed to be more or less parallel to the sensor plane. Turns out they are expensive, and we haven’t done it yet. In any case in frustration at the non-repeatability I chucked out all the dull test images from the Sony 50, Sony 90, cv 110, anon MPE and Laowa 100 that I had taken intending to replace them when I get around to a serious (and more hassle free) macro testing rig.
So FWIW I thought that, based not on an etched target, that the Sony was a touch contrastier and sharper than the CV at 1:1, but the reverse was true at 1:2 to infinity. Of course this might be within sample variation.
I might also add that both are great, and I absolutely wouldn’t use the resolution differences to make my decision. I’d choose on preference for AF or not primarily. Or if you are allergic to a little residual loCA I’d get the CV.
The bokeh is a bit nicer on the Sony at 1:1... I think there is a small sample of that in Phillip’s and my review of the 110. But again, that’s distance dependent. ...Show more →
Bob Atkins used to sell slides he'd shot of test charts (if memory serves, the one shot with the 300/4L was the best of them) that made flat 1:1 comparisons relatively simple with an ES-2 like contraption. If that interests you, you could reach out to him and see if he still has the kits available.
Alternately, reproduction stands are relatively cheap and they make it easy to keep the camera in the same position and square with the target.
freaklikeme wrote:
Bob Atkins used to sell slides he'd shot of test charts (if memory serves, the one shot with the 300/4L was the best of them) that made flat 1:1 comparisons relatively simple with an ES-2 like contraption. If that interests you, you could reach out to him and see if he still has the kits available.
Alternately, reproduction stands are relatively cheap and they make it easy to keep the camera in the same position and square with the target.
Now that's a nice idea! If it's no trouble, I might well be interested in such a slide! I do have a repro stand in the garage somewhere. But nowhere where i'd get permission from the household gods to set it up permanently (and I can't see myself moving it and setting it up just for this purpose)
DavidBM wrote:
Now that's a nice idea! If it's no trouble, I might well be interested in such a slide! I do have a repro stand in the garage somewhere. But nowhere where i'd get permission from the household gods to set it up permanently (and I can't see myself moving it and setting it up just for this purpose)
I sent an e-mail to Dr. Atkins. I'll let you know what he says.
Another idea would be to print a test chart on transparency or backlit paper (frosted transparency, basically) at slide dimensions. My printers probably wouldn't produce anything usable at that size, but if you have access to a laser printer that will work with the unusual media, it might be worth a try.
freaklikeme wrote:
I sent an e-mail to Dr. Atkins. I'll let you know what he says.
Another idea would be to print a test chart on transparency or backlit paper (frosted transparency, basically) at slide dimensions. My printers probably wouldn't produce anything usable at that size, but if you have access to a laser printer that will work with the unusual media, it might be worth a try.
I considered doing that, but the problem is getting the resolution high enough in something so small.
I don't have access to anything that could do it.
I also worry about the slide idea, depending how Bob implemented it. Because the resolution of the image on the slide may be too low to be a good test of todays high resolution macro lenses.
That's why etched glass test subjects are the go-to solution. But Atkins knows what he is doing, so he may have it right (or he may have something that worked quite well a decade or so ago, but which won't distinguish much between contemporary macro optics)
DavidBM wrote:
I considered doing that, but the problem is getting the resolution high enough in something so small.
I don't have access to anything that could do it.
I also worry about the slide idea, depending how Bob implemented it. Because the resolution of the image on the slide may be too low to be a good test of todays high resolution macro lenses.
That's why etched glass test subjects are the go-to solution. But Atkins knows what he is doing, so he may have it right (or he may have something that worked quite well a decade or so ago, but which won't distinguish much between contemporary macro optics) ...Show more →
No matter what media is used, what you're going to see is the flaws in that media. Since it's less about the absolute performance metric of the lenses themselves and more about how they compare, it's going to be more about how detailed the flaws look compared to the others.
freaklikeme wrote:
No matter what media is used, what you're going to see is the flaws in that media. Since it's less about the absolute performance metric of the lenses themselves and more about how they compare, it's going to be more about how detailed the flaws look compared to the others.
If the lines on the chart aren't sharp enough, it becomes very hard to distinguish the amount by which the lenses you are testing soften them. In the limit, if lines aren't discriminable from each other in the test (which was the case with some targets I tried) you can't count them!
Perhaps the 110 apo is not the most suitable lens for making portraits, but I am curious how that would turn out instead of a more common 85mm 1.4
Can't find much about it on the internet, is there someone dedicated with portraits and the 110 apo?
