ImageCreator Loc: Northern California

This is a following up to my Aug 31st post on the same subject.
In my internet research I read an article on Flipboard where the photographer is using stacking photography in place of using an ND filter. His reasoning is that when using an ND filter you are subject to blurring due to the long exposure. Now this blurring might be what you want if its water, but you also get blurring from wind. Consequently, the image is not sharp. So, in the article the photographer takes a series of static photos from the same position, then stacks them together in photoshop to create a more dynamic, sharper image. His example showed a photo of the New York skyline with clouds and lightning. He captured 267 images and then used the best ones in a stack to create his final image.
Here is his photoshop process:
1. assemble your images
2. go to file, scripts, load stack (files need to be the same diminsions)
3. if the files are raw then click on "add open files."
4. click on auto align
5. in the layer menu, click on smart object, stack mode and choose either median or mean.
6. then wait while ps does its magic.

I have not tried this yet but will when I can shoot a bunch of the appropriate images.

I would imagine this would work best with a scene with changing lighting conditions, like a sunrise/sunset or cloudy storms.

It also looks like you will need to spend a lot of time recording the images, like and hour or more.

If any of you try this please show us the results.

Rongnongno Loc: FL

Not sure what you are getting at.

267 exposures for a single frame? Select the best ones to stack? Basically your guide is mass shooting then tosses most of his images. Not a good example to follow.

Stacking is not exactly hard to do if one respects simple rules. Freezing a scene for any stacking is one of them. Using the same exposure is another - including white balance. Using a tripod is not an obligation, but a must if critical for the final result.

The rest is simple processing, regardless of method used.

Stacking is usually used to:
- Remove sensor and/or some environmental noise
- Removal of objects from a scene, cars, peoples, whatever
- Augmenting the field of focus from landscape to macro subjects.
- HDR (Using raw offers better results)
- Panoramas (images are stacked before stitching for any of the reasons mentioned above)

In no case, there is a requirement for the hundreds of images mentioned, unless it is for a stacked panorama.

Quixdraw Loc: x

Or the Moon! https://www.diyphotography.net/this-epic-81-megapixel-moon-photo-was-stacked-from-50000-images/

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If you get wind motion blur from a slow shutter speed, you will get wind motion blur from stacking.

Stacking gives a slightly different looking blur than slow shutter blur, and acoarst the same applies to water motion blur.

BTW I concur that 267 images is absurd. But some writers really seem to invent their bizarre impractical techniques not for the images that result but to give themselves something to fill their blog pages, and to appear as wizards before their naive readers. It even occurs right here in Hawgland ! There are some who treat the open forum as if it were their blog space.

one_eyed_pete Loc: Colonie NY

I'm not understanding what this has to do with using a ND filter. Typically you would use a ND filter when you have so much light that you can't slow the shutter down enough or open the f stop enough to get the shot you want???I would think stacking would be the exact opposite technique to using a ND filter. What am I missing?

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If you can’t slow your shutter below 1/100”, you can shoot 25 frames at 1/100” each and then stack them. The effect as regards rendering motion will be similar to shooting at 1/4” cuz whatever moves is never quite the same from frame to frame.

You should notice that the *total* exposure time actually is 1/4” even though it’s the sum of many shorter exposures. Daylight could easily require f:45 or f:64 to shoot a single frame at 1/4”. This is where the comparison to a neutral density filter slips in. A 1.5 or 1.8 density would allow 1/4” in daylight at a more reasonable aperture, around f:8 or f:11 instead of f:64.

ImageCreator Loc: Northern California

I'm relating what the article said. Personally, I would probably use maybe ten images over an hour. Don't kill the messenger

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Fear not. The Hawgland Fraternal Order of Dead Messengers is THE most highly respected elite club around here.

one_eyed_pete Loc: Colonie NY

Thanks for the explanation, I get it now. The only application I can currently think of would be trying to blur moving water. I guess the still surroundings could be crisper but I don't know if which version of the moving water would be better? If you did shoot 25 frames at 1/100 sec the blur duration/movement would be equivalent to a 1.5 to 2.5 sec exposure depending on the frame rate of your camera. It would be an interesting test to see the difference.

tgreenhaw

I think there is some confusion about semantics. Stacking is usually used to describe techniques for HDR and increasing DOF. There are some other related techniques that are referred to as stacking.

Adobe has more Info on this: https://helpx.adobe.com/photoshop/using/image-stacks.html

According to Adobe, "You can use image stacks to enhance images in number of ways: To reduce image noise and distortion in forensic, medical, or astrophotographic images. To remove unwanted or accidental objects from a series of stationary photos or a series of video frames. For example, you want to remove a figure walking through an image, or remove a car passing in front of the main subject matter."

I plan to try this as well :-)

Rongnongno Loc: FL

rotflmao

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Very interesting point. There’s the actual “event time” passing by as separate from the total exposure time.

I never considered “event time”. While I hadn’t put a number on it, I can say my mental image of shooting 25 frames was approximately a heartbeat. Although I generally shoot in single frame, when I need burst, I need burst. It’s always set for the max. 1/100” should allow about 45fps. No AF, no mirror, no shutter, just continuous recording.

The idea that 25 frames could need over 2” simply never crossed my mind. To me, thaz like my old film era action cameras.

mikegreenwald Loc: Illinois

Right on. Very useful when you behave as stated in this reply!

SuperflyTNT Loc: Manassas VA

You’re wrong. Some people do stacking to simulate long exposures for smoothing out water and clouds. In that case it’s not uncommon to use 300 images. I’ve also used over 200 images for macro focus stacking. Another use of stacking with long exposure Ives used is light trails when there wasn’t enough traffic in one shot. Of course then I only be use a few frames. I’m looking forward to some light trail photography using Live Composite in my Olympus E-M1X. You can actually watch the light trails building and stop the exposure when you get the result you want.

Blaster34 Loc: Florida Treasure Coast

Thanks QD, one of the pretties images of the moon I've seen...