philip_pj wrote:
It is difficult to tolerate visible CA in an APO lens, and lens makers are routinely hauled over the coals for even minor trangressions. Right or wrong, people associate APO with perfection. Ted does a small amount of apologia which is understandable for reviewers. But high contrast is ever-present in a lot of outdoor shooting.
The CA he sees in his images are not something we'd be happy with in say, the CV 50/2 or the SL APOs, and the better commercial lenses also, Sony's GM 50/1.4 and GM 50/1.2, others too. They are rather obvious, even in YT's compression. A related finding is that the lens at f2 sees a significant lift in performance, indicating its main role might be wide open, dreamy trad sharp plane - smooth bokeh portraits, in *controlled* lighting.
The reason Cosina and Leica use f2 as their main max apertures for their numerous APOs is that they can engineer them to perform as well at f2 as any subsequent aperture setting. Here are a few snips courtesy of Ted's YT video to show what is meant here:
I see the glass as half full with these examples. Yes, the lens does have some axial CA in some shots at f/1.4. Yes, the lens does sharpen up a bit when you stop down from f/2 from f/1.4. What that means to me is that it has a different and I think really pleasant look at f/1.4 and a different really sharp look when you stop down. In many ways this reminds me of my favorite 50mm lens--the Leica M 50 f/1.4 Asph (note Peter Karbe has said it could have been labeled as APO but wasn't). That lens certainly has as much axial CA at f/1.4 as this Milvus lens, but if you know how to use it you know how to avoid the axial CA. It has a beautiful look at f/1.4. It isn't unsharp, but it does sharpen up as you stop down. I think this 50 Milvus ML will be like that lens, but will be better in not having the Leica's field curvature, which is another aspect of the lens you have to work around.
Simply put, I am not worried about these examples of axial CA. It can be handled in two ways, I suspect--but time will tell. First, you can avoid harsh contrast lighting. In my use that often involves moving to the shade for the outdoor portraits. Second, you can simply stop down to f/2 with this lens and you will avoid the axial CA even in the worst case lighting. That makes this axial CA an issue, but not one that can't be dealt with and I think I really like the look of the images and especially the bokeh, but I still want to see more examples of the lens' performance and hear more from people who have used it more. Personally, I think it might well become one of my favorites, but we'll see.
Mar 02, 2025 at 04:39 PM
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