What went wrong?
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What went wrong?
Trying to improve the lighting, this stack was shot 1:1 with a Canon T3i/100mm macro lens and 3 Ikea LED lamps shining on a paper diffuser at f/7, 1/4 sec, ISO-100. Is the blurring due to vibration?
Martin
Martin
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- Posts: 145
- Joined: Sat Feb 09, 2013 4:54 am
- Location: Ipswich, Suffolk, UK
Much better though not exactly pin-sharp, here is the aligned version:
This is as sharp as the best bits of each of the individual shots, which still isn't exactly pin-sharp. I'll relocate the stacking setup to somewhere where I think it will be less likely to move about.
Is 1/4 sec an appropriate exposre time for a continuously lit subject? i chose it as it seemed to be the longest time that didn't over-expose with a small (f/7) aperture. Maybe it would have been better to increase the time and compensate by reducing the light by adding a layer or 2 to the diffuser?
Martin
This is as sharp as the best bits of each of the individual shots, which still isn't exactly pin-sharp. I'll relocate the stacking setup to somewhere where I think it will be less likely to move about.
Is 1/4 sec an appropriate exposre time for a continuously lit subject? i chose it as it seemed to be the longest time that didn't over-expose with a small (f/7) aperture. Maybe it would have been better to increase the time and compensate by reducing the light by adding a layer or 2 to the diffuser?
Martin
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My experience is primarily with continuous (non flash) illumination. I have always photographed with a "mirror up delay" mode on my Pentax cameras. I have found by testing with my rig that I get the best sharpness when I use longer (2 sec) rather than shorter (1/5 sec) exposures.
This link allowed some interesting discussion on the topic.
http://www.photomacrography.net/forum/v ... =vibration
And this link is where I actually measured the "thumps" from the various mechanical processes in my camera.
http://www.photomacrography.net/forum/v ... =vibration
I suggest you try longer exposures.
More modern cameras than the Pentax *ist DS I used on this test have been redesigned and don't thump as hard. The design has improved.
Flash illumination avoids this mostly as the flash period is so short, much shorter usually than the vibration frequency.
Good luck!
Keith
This link allowed some interesting discussion on the topic.
http://www.photomacrography.net/forum/v ... =vibration
And this link is where I actually measured the "thumps" from the various mechanical processes in my camera.
http://www.photomacrography.net/forum/v ... =vibration
I suggest you try longer exposures.
More modern cameras than the Pentax *ist DS I used on this test have been redesigned and don't thump as hard. The design has improved.
Flash illumination avoids this mostly as the flash period is so short, much shorter usually than the vibration frequency.
Good luck!
Keith
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- Posts: 145
- Joined: Sat Feb 09, 2013 4:54 am
- Location: Ipswich, Suffolk, UK
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- Posts: 145
- Joined: Sat Feb 09, 2013 4:54 am
- Location: Ipswich, Suffolk, UK
I've now fastened everything down and adjusted the diffuser so I could shoot at f/5, 0.8 sec. Taking great care not to jiggle anything, I shot this stack of 35 images using same T3i with the 100mm 2.8L macro lens lit with 3 LED lamps and paper tube diffuser. The output is PMax with no retouching then levels, saturation and sharpness adjusted.
I'm much happier with the result now, even though this battered dusty fly is hardly a work of art...
Martin
I'm much happier with the result now, even though this battered dusty fly is hardly a work of art...
Martin
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Thanks for your comments Here are a couple of 100% crops, which demonstrate as usual that there is always room for improvement...
Suggestions on how to improve welcome... It's great not to have to worry about batteries, and to be able to preview the lighting in real time with the LED lamps, but there something very sharp about a flash, isn't there?
Martin
Suggestions on how to improve welcome... It's great not to have to worry about batteries, and to be able to preview the lighting in real time with the LED lamps, but there something very sharp about a flash, isn't there?
Martin
Are you sure those are 100% crops and not upscaled? They look very much like something has scaled them to beyond 100%.
Edit: Doing some calculations - your 100% fits 8.4 times across the width of your first image. Meaning that assuming the first image was uncropped, the original image must have been 8595 pixels wide. Which results in a 47MP image... The T3i is 18MP.
Edit: Doing some calculations - your 100% fits 8.4 times across the width of your first image. Meaning that assuming the first image was uncropped, the original image must have been 8595 pixels wide. Which results in a 47MP image... The T3i is 18MP.
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