Steve Wake
Well-known member
@Mike: Minimum focus doesn't change because of a crop sensor. Technically, magnification doesn't change either (just like a crop sensor doesn't change the focal length of a lens), but the actual effect of a crop sensor is to increase magnification (just like a crop sensor gives the effect of increasing focal length).
So on a Zeiss 100, which has a maximum magnification of only 1:2 (not the 1:1 of most macros), the effective magnification would be 1.5 x 1:2 = 1.5:2 = .75:1 Similarly, a 1:1 macro would get multiplied to 1.5:1 Stills shooters who do a lot of macro sometimes favor crop sensors to take advantage of this effect, sometimes referring to it as increased pixel density (to distinguish the effect from an actual increase in magnification). (technical footnote: 1:1 magnification means the image of a 24mm high object would fill the height of a standard 24mm high FF35 film frame or digital sensor. With a 1.5 crop sensor, using a 1:1 macro lens set to 1:1, a 24mm high object still projects a 24mm high image at the focal plane of the sensor, it's just that the "image" extends beyond edges of the sensor, as if it was magnified by 1.5x).
I shoot Nikon, so I can get effectively over 1:1 with my ZF 100 by adding the very solid PK-13 extension ring.
I've never seriously shot macro video - only played with it a bit with my D7000 in (crappy hobbyist) video mode. I was really looking forward to the 2/3 Scarlet to take advantage of the ~3.8 x magnification multiplier, but .... oh well. I do have more experience with stills macro, so extrapolating from that, here's some food for thought:
1) get a long macro like a Sigma 150. I've never used it, but it has an excellent reputation and is a true APO lens. At 1:1 effective magnification on a S35 sensor (i.e a 16 mm high object more-or-less fills the height of the frame) your working distance from the front of the lens will be about 1 foot. If you get a 100-105 the working distance will be 7-8 inches. With a 55 or 60 you'll scare the critters or probably interfere with light.
2) I don't know what your plans for finishing are, but if you're finishing in 2K or HD, try framing extremely large in order to get more dof and minimize or preferably eliminate camera movement. Frame and track action in post.
3) Alternatively, control movement of your subject and plan a path for your camera to track the action. Just be aware that the slightest change in camera to subject distance could ruin a shot due to breathing (if you maintain focus) or losing focus altogether, i.e. simple tilting and panning might not work. You might also need a rack (like the geared focusing rail stills shooters use).
4) Consider a tilt/shift lens to adjust the plane of focus to include the projected path of movement. The Nikon 24mm T/S works well with a small extension ring. That's the only T/S I've ever tried that way, but others may also work.
Hope this helps.
So on a Zeiss 100, which has a maximum magnification of only 1:2 (not the 1:1 of most macros), the effective magnification would be 1.5 x 1:2 = 1.5:2 = .75:1 Similarly, a 1:1 macro would get multiplied to 1.5:1 Stills shooters who do a lot of macro sometimes favor crop sensors to take advantage of this effect, sometimes referring to it as increased pixel density (to distinguish the effect from an actual increase in magnification). (technical footnote: 1:1 magnification means the image of a 24mm high object would fill the height of a standard 24mm high FF35 film frame or digital sensor. With a 1.5 crop sensor, using a 1:1 macro lens set to 1:1, a 24mm high object still projects a 24mm high image at the focal plane of the sensor, it's just that the "image" extends beyond edges of the sensor, as if it was magnified by 1.5x).
I shoot Nikon, so I can get effectively over 1:1 with my ZF 100 by adding the very solid PK-13 extension ring.
I've never seriously shot macro video - only played with it a bit with my D7000 in (crappy hobbyist) video mode. I was really looking forward to the 2/3 Scarlet to take advantage of the ~3.8 x magnification multiplier, but .... oh well. I do have more experience with stills macro, so extrapolating from that, here's some food for thought:
- Anything moving, especially in unpredictable ways, like insects, will pose a lot of challenges given the razor thin dof you work with in macro.
- If you think AF will work, try it first - it may not work the way you like on every lens: speed, accuracy, and possibly major breathing issues.
- If you plan to manual focus, focus throw and breathing could be major issues.
- If you think you'll do this handheld, think again.
1) get a long macro like a Sigma 150. I've never used it, but it has an excellent reputation and is a true APO lens. At 1:1 effective magnification on a S35 sensor (i.e a 16 mm high object more-or-less fills the height of the frame) your working distance from the front of the lens will be about 1 foot. If you get a 100-105 the working distance will be 7-8 inches. With a 55 or 60 you'll scare the critters or probably interfere with light.
2) I don't know what your plans for finishing are, but if you're finishing in 2K or HD, try framing extremely large in order to get more dof and minimize or preferably eliminate camera movement. Frame and track action in post.
3) Alternatively, control movement of your subject and plan a path for your camera to track the action. Just be aware that the slightest change in camera to subject distance could ruin a shot due to breathing (if you maintain focus) or losing focus altogether, i.e. simple tilting and panning might not work. You might also need a rack (like the geared focusing rail stills shooters use).
4) Consider a tilt/shift lens to adjust the plane of focus to include the projected path of movement. The Nikon 24mm T/S works well with a small extension ring. That's the only T/S I've ever tried that way, but others may also work.
Hope this helps.
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