Focus Stacking

Hi,

maybe this is question where the best answer would be: Go outside and try yourself. But unfortunately it's cold and grey outside so I decided to get some theoretical info first.

I found a lot of information about focus stacking when it comes to macro shots but less when it comes to landscapes.

Of course there's hyperfocal distance and one can stop down, but sometimes you must stop down to a level where diffraction sets in so it could be useful to use focus stacking.For example: Flowers in the foreground (maybe 3 feet away), then a lake, and behind the lake some mountain scenery.

My question: How many frames would you try in such a case? Of course one for the flowers closest to the camera and one for the mountains. But how many for the area between?

Thanks
Richie

That's the easiest part of focus stacking.

If using wide angle (lower than 24mm) set the lens to f5.6 or f8 or whatever is the sharpest across the frame. Take a photo of your nearest object with it in focus. Play back the image and find the point where you start losing focus again. You need to zoom in to see this. Then focus to that point. Repeat until your furthest object is in a focused frame. You need less and less photos as you gain distance.

For longer lens such as over 100mm, you may have to stop down to f13-16. Otherwise your DOF is way too thin and the high number of closely spaced stacks will be a nightmare and even impossible to stack. Focus stacking can only get you so far before digital artifacts and rules of physics diminish all returns.

You are best practicing indoors or somewhere not important, because you will screw it up for sure and regret not properly capturing great moments.

That should answer your question, but there is much much more to it if you plan on printing large, which is the whole reason for doing this in landscapes. It would take me writing a 100 page book on all the aspects of simple and advanced stacking to a finished product.

It depends.

So I'm a big fan of focus stacking for landscapes, and I agree, there s not much out there. So I'll give you my take (some things are mentioned in the post by Canon_Lover).

Two things you will notice about focus stacking:

1. if something in the foreground is very OOF when the immediate background is in focus you will have a 'dead' zone where you do not have anything in focus. The OOF foreground obscures the background that is in focus. Thus, sometimes you may want to stop down more than the optimum aperture of your lens to ensure this does not happen as it will create a halo. This may happen with long FL more than short ones, but can happen with wide angles too.

2. although you get some diffraction softening as you stop down, something in the focal plane at f16 will be a lot sharper than something at the edge of the DOF (even at f22 this is very true). Therefore, even if you can get everything in 'acceptable' focus at the hyperfocal distance, you will get an overall significantly sharper image (especially in the near corners) if you focus stack at that same aperture. Thus a focus stack of just two shots at f16 (one focused on the very near objects and one at infinity) will already produce a much sharper image than an f16 shot at HFD. This technique is also useful if something in the foreground is moving (e.g. grass in the wind).

Having said all that, for me a typical focus stack at f11 (FF) would be 3-5 shots depending how close the nearest object is - well usually I make sure the near corners are as sharp as can be. I might go 1-2 shots extra on the near end because that is the hardest to determine where to start/stop, even with LV.

If something is so close that hyperfocal focusing at f16 leaves the near objects obviously OOF, you may need more like 7 or more shots (more at the near-focus than at far). Notice that the focus ring distance scale is not linear - try to get each turn about the same amount between shots.

Personally I don't go more open than f8 because I find I just need too many shots and the corners of my lenses are not that sharp. For landscapes I prefer to rotate the focus by hand, rather than have Magic Lantern do it for me (or EOS or other computer-based program).

All else being equal, more shots is better, especially if you are automatically combining them. Perhaps start with twice as many shots for anything critical. But this also takes unnecessary time which can be at a premium at dawn and dusk. Another thing I do is take a dark shot (hand in front of lens) in between stacks when working a scene since it can be easy to loos track of the start/end of the stacks - especially is you make a mistake and have to start over. Also try to move focus only one direction, don't go past your next focus and more back - for some reason I find you don't always get to where you think you should be and the focus stacking software might have problems.

Hope that at least helps you figure out where to start experimenting.

EDIT: IMO focus stacking for landscapes is quite a bit different technically than for macro. I do use it a lot for macro, but the whole process and things to worry about are quite different.

Thank you guys. I guess when the weather gets better I will give it a try.

thanks. I was searching on this topic as the instructions from the web are getting me confused.

I'd liked to try for macro, shooting with a 100L & 180L lenses. Will have to use a tripod.

As I understand from the above, we should shoot at max DOF.

As for the number of pictures needing to stack, what are your normal #. I read 5 - 6 pictures. Is there any touch & feel guidelines on this ? Similar to HDR (where I will use between 3 - 8) ?

Here's a video tutorial for you to watch in the meantime... https://www.youtube.co​m/watch?v=IMiKUnVAFks

lensmen wrote in post #15526407
thanks. I was searching on this topic as the instructions from the web are getting me confused.

I'd liked to try for macro, shooting with a 100L & 180L lenses. Will have to use a tripod.

As I understand from the above, we should shoot at max DOF.

As for the number of pictures needing to stack, what are your normal #. I read 5 - 6 pictures. Is there any touch & feel guidelines on this ? Similar to HDR (where I will use between 3 - 8) ?

2-7 for landscapes, yes. For macro, no. You're looking at sometimes up to 90 shots. I think it is smart to use automation for macro stacking. That would suck to dO manually.

I am curious about focus stacking. I love the look that can be achieved when using it, but always assumed that one would need some kind of special photo editing software (like Elements or Lightroom, or worse yet, some type of "plug in") in order to do it. Is this the case, of can I just do it with my basic iPhoto program?

http://www.naturescape​s.net …o-avoid-lens-diffraction/


.

^^^
Good way of dealing with this.
I knew a free software just made for this reason, only if I could remember its name. But then as long as you have CS, it should be fine.

@Canon_Lover

Wow. thats more than I thought. thanks for the reminder.

Hopefully the full featured Magic Lantern for the 5D Mk3 will be out soon. There is a stacker function in the 5D Mk2 version, but did not understand what it actually does, until this attempt.

@ Motor On

Thanks for the Youtube link. Will check it out.

@ samsen

Freeware stacker ? You mean CombineZ ?
CombinZ

Let hoped that tomorrow morning, the weather and light holds. Will post an update here when I managed to do it. ^-^

Tom Reichner wrote in post #15526665
I am curious about focus stacking. I love the look that can be achieved when using it, but always assumed that one would need some kind of special photo editing software (like Elements or Lightroom, or worse yet, some type of "plug in") in order to do it. Is this the case, of can I just do it with my basic iPhoto program?

Really you do need special software unless you have a $40k cine lens. This is because the effective FL changes slightly as you focus at different distances, so each image needs to be scaled to match a master image. It is actually also a little-talked about point that does slightly affect the final image quality, but its minor compared to the benefits.

I use Helicon focus, but I hear that zerene stacker (http://zerenesystems.c​om/cms/stacker) is now a popular solution. The freeware might also be a good way to get started.

I think both non-freeware programs have 30day free trials, so you could have 2 months of trying it out. PS has something, but I don't think it has all the features you'd really want, I could be wrong, but is seems most people who really do a lot of focus stacking use other software (I don't have PS, so maybe it works just fine for landscapes).

And then for Macro, if you are doing anything where you don't want to hook up the camera to a computer, you really want Magic Lantern to drive the stacking. Personally I don't think I've gone to 90 shots, but I've certainly done 40-60 and 90 isn't outrageous, especially if you are using an MP-E 65. I can't see how it would be possible by hand.

So, yes it does really require some extra 'commitment'.

For those using PS, elements or similar, but don't want to focus stack, you might also consider aperture stacking - shoot at various apertures (say f8, f11 and f16) and blend in PP to get the best of each. The blending is usually fairly straightforward and the images line up perfectly, but obviously doesn't have the benefits of focus stacking. The shots could also be blended automatically by focus stacking software.

lensmen wrote in post #15526407
As I understand from the above, we should shoot at max DOF.

Well it's a trade-off. Large aperture may be sharper, but you might miss something or have to take a lot of shots (which can take a long time and might not be practical outdoors). Small aperture and you will reduce resolution.

With my 2.8 Macro, I will usually use between f5.6 and f11 for focus stacking macro. The lens is actually sharpest around f4.

Motor On wrote in post #15526483
Here's a video tutorial for you to watch in the meantime... https://www.youtube.co​m/watch?v=IMiKUnVAFks

Great video.

Thanks Lensman. That is correct. Wonderful 1.