I just received my Zhongyi 20mm 4-4.5X lens a couple of hours ago, and this is my first try with it. Subject is part of an old dried up flower of some kind. Lens was set to f/2 and 4X. Camera was set to manual and live view. Camera was mounted on my SWEBO focus rail and moved in 0.1mm increments, 34 times. Only minor edits were made in post. It appears that I didn't go far enough to catch everything in the lower left corner. This reminds me of using my large format camera and having to look at everything closely.
If I'm not mistaken, I think that f/2 at 4x is equivalent to around f/8 on a "normal" lens. Please correct me if that's not true. Apparently, many of these high magnification lenses are sharpest (least diffraction) at the smallest f stop.
I think I'm going to like this little $150 lens. There's an old dried out mushroom head that I'm going to take a look at later tonight.
Very interesting and intriguing lens.
--Bob
jackm1943 wrote:
I just received my Zhongyi 20mm 4-4.5X lens a couple of hours ago, and this is my first try with it. Subject is part of an old dried up flower of some kind. Lens was set to f/2 and 4X. Camera was set to manual and live view. Camera was mounted on my SWEBO focus rail and moved in 0.1mm increments, 34 times. Only minor edits were made in post. It appears that I didn't go far enough to catch everything in the lower left corner. This reminds me of using my large format camera and having to look at everything closely.
If I'm not mistaken, I think that f/2 at 4x is equivalent to around f/8 on a "normal" lens. Please correct me if that's not true. Apparently, many of these high magnification lenses are sharpest (least diffraction) at the smallest f stop.
I think I'm going to like this little $150 lens. There's an old dried out mushroom head that I'm going to take a look at later tonight.
I just received my Zhongyi 20mm 4-4.5X lens a coup... (
show quote)
Very good. I like the minute textures.
rmalarz wrote:
Very interesting and intriguing lens.
--Bob
Thanks Bob. I think it will take a while to get on top of it. Fairly soon I want to determine how far, if at all, I can stop down before seeing serious diffraction.
Thanks for the interesting article, including the calculator. The calculator indicates that at my usage (f/2, 4X) I need 0.027mm increments. I will examine this image more carefully to see if there are some out of focus areas that I didn't see.
Mark Sturtevant wrote:
Very good. I like the minute textures.
Thanks for looking in Mark.
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