Here's a lady slipper from my collection. I'm using my MacBook Pro for the first posting on this site. Want to know how it looks on a PC. My technique is with a fill flash not natural lighting. Canon EOS- 1D, EF 100- 400 mm f/4.5 - 5.6 L, 550 EX flash and my tripod.
All photos of the orchid that I've seen look strange when judging sharpness. Does not look sharp to my naked eye either. The strips are not well delineated on the plant.
Enjoy
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Charlie Wesley
St. Augustine Beach, FL
Hi Charles,
Orchids are so 3-dimensional that depth-of-field (DOF) control and attention to the center of focus are critical. What were your actual shooting parameters (f-stop, shutter speed, exposure comp (on camera and flash), working distance, and actual focal length? In addition to using good camera steadiness techniques, any of these parameters will influence your image quality. For this lens, the IS should be turned OFF when using a tripod. The 100-400 can make some decent macro images, but a wider angle lens may work better if you have the option of moving close to your subject, since you will gain some DOF. Adding an extension tube will allow even closer focus, but on-camera flash then becomes problematic, since you may overshoot the subject. In that case an off-camera flash cord or a macro flash ring (such as the MR-14) would be needed. I suggest focusing manually for precise control of the central focal plane.
In this image, the hairs and stripes on the lateral petals and the stripes on the upper petal are good indicators of sharpness at different focal distances.
Here are all the details I can find. I always turn IS off on 100- 400 when on a tripod. Shot MLU and self timer set. Manual exposure was 1/3 sec. @ f/10.0 ISO 320. My 100- 400 was set to 250 mm. I think I had the flash set to 1/ 64 manual power and was definitely angled down onto the flower. I see the labellum, top sepal with white, green, burgundy lines and hairs on the lateral sepals in focus.
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Charlie Wesley
St. Augustine Beach, FL
Last edited by Charles Wesley; 05-14-2009 at 05:27 PM.
Charlie,
You did use a fairly long focal length with a slow exposure. That increases sensitivity to the blurring effect of any vibration. It's good that you used the timer at that shutter speed, but the shutter/mirror movement probably initiated enough vibration at that exposure to cause slight blurring. Here are some other things you might consider:
1. Using mirror lockup would eliminate vibration from that source (but not from the shutter itself). I'm not sure whether mirror lockup will work with the timer function. If you're doing a lot of macros like this you would find a cable release useful anyway.
2. Are you using a daylight or UV filter? That can degrade IQ slightly by introducing an additional optical element.
3. The zoom ring should be locked so the linkage is tight.
4. Make sure the camera/lens combo is well balanced over the tripod mount.
5. The tripod, ball head and all linkages should be rock solid. Try very lightly tapping the camera while you look through the viewfinder at a target. How much movement results? Also, watch through the viewfinder (without touching the camera or tripod) to observe whether there is apparent residual motion immediately following exposure.
6. Try damping vibrations propagated from the shutter with a beanbag or gel pack draped over the rig, as long as this does not overload your tripod.
7. The flower has a long stem and will be sensitive to the slightest air movement -- e.g., breath, convection or cross-ventilation.
8. If your camera has good noise control, you might increase the ISO a stop or so and increase shutter speed accordingly. Increased light would would also allow faster shutter.
Best wishes,
Craig
Last edited by Craig Markham; 05-15-2009 at 12:54 AM.
I think Craig has covered the technicals quite well so let me say that aesthetically I like this image. I am not overly fond of the BG color compared to the tones of the flower - I think it helps it melt into the BG instead of giving it that stunning punch that orchids tend to have. That said, I think you did a nice job on the focal points - these are VERY hard flowers to photograph because of all the different focal planes they cover and you did a really nice job on it.
Lady Slipper
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