![]() ![]() I'd be tempted to open a dialogue with you off-line if you like, so we don't distract from the OP's direction. Your illustrations are immensely informative. Quote from: Hank Keeton on January 19, 2014, 01:29:22 pm -Hopefully this is not too off-point for the OP, but Doug, I'd like to congratulate you on your very systematic presentation and discussion of "Extreme" macro work. ANY bump in the camera left or right, even lightly tapping on the highly-levered-due-to-extension rear standard would chance registration by several pixels.įor what you're doing I'd focus more on the basics - high shutter speed, sharp aperture, solid tripod, repeated practice to find the various pitfalls. Remember that at the magnification I was shooting I had maybe 5000 pixels going across a 2mm area of subject matter, which means each pixel covered less than a micron of subject matter. ![]() It's also difficult to turn the focus wheel on a large-extension view camera 100 times, in even increments, without ever accidentally bumping the camera slightly left or right. moving a view camera on a linear slide, especially if its' pointed down at an angle. For instance it's a lot easier to move the weight of a fly's eye forward and backward in even increments on a linear slide vs. There are pros and cons both optically, mathematically, and in practicality. You use a motion table to move the subject through the plane of focus, is this to avoid having to touch or disturb the camera or do you feel that there is some optical advantage over moving the plane of focus through the subject as I do by adjusting the lens?īoth methods work, but moving the subject IMO becomes preferable as you get into very high magnification. I had to turn off the A/C, take shallow breaths, use a sturdy table (and not actually touch the table at any point) and work some zen in the way I actuated the linear slide.Īt lower magnifications the requirements to reduce vibration are not nearly as onerous. At such high magnifications and with so many frames required for the stack, ANY vibration is severely detrimental. My article was specific to macro magnifications in the ball park of 10:1. "Macro" photography covers a lot of technical range. I note that you shoot in the dark to avoid shutter 'shake' but do you feel that extraneous ambient light or slight over exposure will reduce the clarity of the image? I slightly underexposed the bike shots to test this (although it's in no way a true comparison) for the brighter areas of the lichen shots appeared the least sharp. Even f/8 might prove to be too narrow to allow low diffraction blur levels. Indeed, I think we are being painfully confronted with Diffraction limited imaging, at high magnification factors.īy calculating the actual magnification factor, you'll be able to more accurately estimate the actual DOF and diffraction limitations, and required focus bracketing intervals/quantities. Quote from: Justinr on January 19, 2014, 12:45:07 pm -I have posted the latest attempt at the lichen below, the discs are approx 1mm in diameter. I also still wonder if you couldn't be getting sharper images. My point here is that you can get plenty of detail if you back off enough to fit the subject within the DOF in a single frame. This time on a tripod.įirst full frame, then a 100% crop which you have to click and enlarge to see fully. Here's another shot this time with a Rollei 6008AF body and the Hasselblad 528c back and 90mm lens at that terribly diffraction ridden f-stop of f/16. Equipment & Techniques > Medium Format / Film / Digital Backs – and Large Sensor Photography
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