What went wrong?

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martincito
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What went wrong?

Post by martincito »

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?
Image

Martin

ChrisR
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Post by ChrisR »

Try running quickly through the preview images in ZS. You might see the subject wiggling as you go, if he moved while you were shooting.
At (only) 1:1 you get more dof, which makes it worse - detail from several slices.

Do you see something sharp in each individual image?

martincito
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Post by martincito »

I just realised I'd turned off alignment :o. I'll redo and post the outcome...

martincito
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Post by martincito »

Much better though not exactly pin-sharp, here is the aligned version:
Image

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

ChrisR
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Post by ChrisR »

Are you shooting from Live View (which uses Electronic Front Shutter Curtain)?

And it's not disabled, eg by having something (anything, even a piece of plastic) in the hot shoe?

martincito
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Post by martincito »

I'm using Live View but I don't think I had anything in the hot shoe. However there is a chance I left a Chinese-made "E-TTL Cord for Canon OC-E3" in place without a flash on the end. I didn't realise that made a difference...

BugEZ
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Post by BugEZ »

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

martincito
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Post by martincito »

BugEZ wrote: I suggest you try longer exposures.
Keith
I certainly will! I guess the trick is to dim the light level by adding a few layers to the (paper) diffuser...

Thanks for your suggestion.

Martin

ChrisR
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Post by ChrisR »

If you're using Canon's EFSC mode there's no vibrations to die down, so I don't think it would help?

martincito
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Post by martincito »

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.
Image
I'm much happier with the result now, even though this battered dusty fly is hardly a work of art...

Martin

ChrisR
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Post by ChrisR »

That's better!
Go on, show as a crop at 100% ;). It should be pretty sharp. Ray would probably the best judge at 1:1!

killawatts
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Post by killawatts »

Wow its light night and day! Looks great. I'd like to see a 100% crop as well.

martincito
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Location: Ipswich, Suffolk, UK

Post by martincito »

Thanks for your comments Here are a couple of 100% crops, which demonstrate as usual that there is always room for improvement...

Image
Image

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

pwnell
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Post by pwnell »

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.

martincito
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Location: Ipswich, Suffolk, UK

Post by martincito »

pwnell wrote:... assuming the first image was uncropped...
The first was cropped to remove the white space around the insect. Here is an uncropped version, reduced to 1024 x 683. The original is 5184 x 3456.

Image

Martin

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