Focus bracket learning exercise - 5 botanical images

GardenersHelper

GardenersHelper

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These five images were created from sequences of focus-bracketed JPEG images captured in natural light with my G80 and Olympus 60mm macro on a tripod. The images were stacked and retouched in Helicon Focus and then given mild processing in Lightroom.

I have written up the background to these images and the techniques used to process them in this post in my Journey thread.

#1 - 74 images, ISO 800, f/5.6, 1/50 sec

1058 1 2017_01_08 P1190127-94 (B,Radius50,Smoothing3+Cetc) LR6 1300h by gardenersassistant, on Flickr


#2 - 34 images, ISO 800, f/2.8, 1/80 sec

1058 2 2017_01_08 P1190398-495 (B,Radius50,Smoothing3+A4,3) LR6 1300h by gardenersassistant, on Flickr


#3 - 89 images, ISO 250, f/2.8, 1/50 sec

1058 3 2017_01_08 P1190550-638 (A,Radius50,Smoothing3+C)v2 LR6 1300h by gardenersassistant, on Flickr


#4 - 98 images, ISO 200, f/4, 1/20 sec

1058 4 2017_01_08 P1190809-42 (B,Radius36,Smoothing3+C) LR6 1300h by gardenersassistant, on Flickr


#5 - 68 images, ISO 200, f/4, 1/80 sec

1058 5 2017_01_08 P1200112-85 (B,Radius50,Smoothing3+Cetc)v2 LR6 1300h by gardenersassistant, on Flickr
 
ChrisA said:
Some nice results with the stacking Nick. The first one seems to have some artifacts in the bubbles to me. Mind you stacking water can be tricky. Others all look nice.
Click to expand...

Thanks Chris. Inside the bubbles I'm seeing what I think are reflections and refractions. I did have to deal with artefacts around the edges of some of the bubbles. Is it around the edges and/or inside the bubbles that you are seeing artefacts? Could you possibly mark up the image to point to the artefacts you are seeing please? That would be very helpful.
 
lightshipman said:
Strangely the reflections are a very similar shape, even though they are on different sides of the subject. So where is the reflected subject? I do like the clarity, just getting into focus stacking my self.
Click to expand...

The camera was pointing almost vertically downwards. Here is what I think we are seeing in the reflections.


P1190127-94 (B,Radius50,Smoothing3+Cetc) LR6 Archive - Annotated crop by gardenersassistant, on Flickr

I'm finding focus stacking a bit of a mixed blessing. With the botanical images I've been doing there are often problems which can be tedious, difficult, time-consuming or impossible to solve. It seems that a few work nicely, some need more or less work to make them acceptable and some resist all (my) attempts to get something acceptable out of them. I don't yet know how invertebrate stacks are going to work out on this spectrum from easy through hard work to impossible.
 
I do like the results I have had from focus stacking, but I have been doing mine indoors, where reflections are more controllable, not exactly studio conditions, I have a landing with a velux window in the ceiling and I came across the 'brilliant' idea of using it as a bit of a studio for taking images , a black cloth back drop and a small table and I was away. When we get a bit more flora in the garden I will try some outdoor.
I never thought of the reflections in your image as cloud, but didn't picture it outdoors.

I couldn't imagine trying focus stacking on insects, though some togs do have some very successful attempts.
I have posted my last focus stack below, the first with a supporting plant stick 'removed' from the image, and the second with a protruding stem removed, this really made it more abstract as it is apparently floating in air and not really a true representation of a growing orchid. I was impressed with result though, editing done in Affinity Pro.

First focus stack by Andrew Wright, on Flickr


affinity stack 1 by Andrew Wright, on Flickr
 
Thanks for sharing your stacks Andrew. I hope you won't mind some detailed observations (extreme nit-picking probably), but I'm seeing evidence of an issue I have been battling with and it may help both of us and others to share what we know about identifying it and handling it.

Curiously, I got a strange result when I downloaded your images and looked at them in Faststone Image Viewer.


NOT MY IMAGE - lightshipman orchid stack by gardenersassistant, on Flickr

I imagine this is a colour management issue with Faststone because XNView shows the image correctly, as does Silkypix. Anyway, it was of interest because of the sharp boundaries around the edges. Did you do some manual masking or some such around the edges?

I'm also seeing some chromatic aberration around edges. For example (and this is full size, but I can see this at normal viewing size), on the flower at the right, blue around the left side edges and orange/red around the right hand edges, and on the upper stem, blue along the lower edge and, much fainter, orange/red along the upper edge. I'm not sure about this, but my guess is that this is not in fact to do with the stacking; I think it can be pretty much removed using chromatic aberration adjustment.


NOT MY IMAGE - lightshipman orchid stack 100pc chromatic edges by gardenersassistant, on Flickr

There is something else I'm seeing which I think is stacking-related. It is something that has been giving me a lot of grief. It is very subtle here, and I think that is partly because of the dark background you have used and partly because of the geometry of the scene.

Note; In the next paragraph I talk of an in focus edge and an in focus area behind it. This is a simplification to make the explanation easier to write (it was getting extremely complicated). In fact, depending on the distance between the two elements and how much depth of field you create by stacking, this issue can arise when an in focus edge is in front of something that isn't in focus, and indeed this is what I think we can see in your image.

What I'm finding is that where there is one edge in focus in front of a surface which is in focus there can be out of focus halos around the edge that can only be handled, if at all, by cloning, as there are no images in which the area concerned is in focus. This is because as the focus moves away from the nearer in focus edge, the nearer edge goes out of focus and the out of focus edge expands, covering the area behind that you want to be in focus. By the time the rear area comes into focus the expansion of the front area's out of focus edge can be pretty large, and blocking the in focus area of the rear element behind it. As a result, there can be no image in which the area behind the expanded out of focus edge is in focus.

Whether this happens depends on the distance between the two elements and how far back from the edge you want to take the stacking. Like I said, it is very subtle here, and probably of no consequence because you may need to pixel peep to see it. But it is something to be aware of.


NOT MY IMAGE - lightshipman orchid stack 100pc slight edge halo by gardenersassistant, on Flickr

I have found this issue extremely troublesome for flowers, buds, seed pod etc images (clearly visible at quite small viewing sizes), and in some cases (well, a fair number actually) it has proved impossible (for me at least) to rescue an image.

Oddly, there are some other halos which seem to be artefacts of the stacking process, depending on what method you use, and in some cases I have found it possible to hide/remove these by blending stacks created using two different methods.

Happy, of course, to discuss all this in greater depth.
 
GardenersHelper said:
Oddly, there are some other halos which seem to be artefacts of the stacking process, depending on what method you use, and in some cases I have found it possible to hide/remove these by blending stacks created using two different methods.
Click to expand...

This whole reply is interesting, I've never seen anything like the first image you have posted in your reply, amazing.on the point of halo's, could this be anything to do with the fact the Nikon D7100 can show moire around the edges due to the lack of an OLPF. I've not got into such close inspection of an image before, interesting.
 
GardenersHelper said:
Did you do some manual masking or some such around the edges?
Click to expand...

All I have done is to remove some extraneous branches, near some of the petals, but I haven't tried to sharpen anything, if there're is any evidence of sharpening I assume it was done by the rendering process in the program. I was amazed really watching it happen as it is my first real attempt of this process, and a process I hope to use again in the future.
I probably need to treat my other half to a bunch of subject matter ( flowers).
 
GardenersHelper said:
I'm also seeing some chromatic aberration around edges. For example (and this is full size, but I can see this at normal viewing size), on the flower at the right, blue around the left side edges and orange/red around the right hand edges, and on the upper stem, blue along the lower edge and, much fainter, orange/red along the upper edge. I'm not sure about this, but my guess is that this is not in fact to do with the stacking; I think it can be pretty much removed using chromatic aberration adjustment.
Click to expand...

I will have another attempt at this and take note of the chromatic aberration issue. To be very honest with you this whole set up was done in about half an hour, I was home from work (dreaded 4 letter word), early, and just fancied taking a photo and having a play. The short days are very restrictive in that you run out of natural light, so things like this become rushed. The result of doing this excercise though has had a positive impact, that I want to do it again! Also I am very new to Affinity Pro, it has sat on my Mac book for about 18 months, not used, and I feel like getting more into it.
 
Nick,
I have just been reading some of your
https://www.talkphotography.co.uk/t...ey-of-exploration.531050/page-17#post-7691787

Thread, I think you use a lot more images than I have done in your stacks. The orchids I have worked with were three image stack. I focussed by eye using live view on my Nikon D7100, and just started at the rear working towards the camera. I have been thinking of buying a focus rail, and increasing the number of images per stack.
 
lightshipman said:
This whole reply is interesting, I've never seen anything like the first image you have posted in your reply, amazing.
Click to expand...

Thanks Andrew. I have to say that I have been surprised by some of what I have seen (when it works ok).

The one below was one of several from my first attempt at hand-held focus bracketing with my new G80 and 60mm macro that made me think this technique has great potential. It doesn't look too special when looking at the whole image


1051 31a FB 40f +3 P1040633 (A,Radius3,Smoothing4) LR6 1300h by gardenersassistant, on Flickr

But when, for an illustration in a post, I did a 100% crop, I was astonished. It does have some faint halos, but I hadn't worked on it much and at that point hadn't become familiar with the tools and techniques for (where possible) dealing with them, and in any case as with your example it didn't matter at normal viewing size. There are three other 100% crops you might be interested to see if you haven't already in the thread this was posted in.

1051 31c FB 40f +3 P1040633 (A,Radius3,Smoothing4) LR6 100pc crop by gardenersassistant, on Flickr

lightshipman said:
on the point of halo's, could this be anything to do with the fact the Nikon D7100 can show moire around the edges due to the lack of an OLPF.
Click to expand...

I don't think so. The G80 that I used for these doesn't have an anti-aliasing filter (which is one of the reasons I bought it!)

lightshipman said:
I've not got into such close inspection of an image before, interesting.
Click to expand...

I've had to, unfortunately, to try to understand what was going wrong with my stacks.
 
lightshipman said:
All I have done is to remove some extraneous branches, near some of the petals, but I haven't tried to sharpen anything, if there're is any evidence of sharpening I assume it was done by the rendering process in the program.
Click to expand...

It wasn't sharpening I was thinking of. It was the areas that are white in the strange-looking (and incorrect) version I saw in Faststone, shown above. Given the sharp boundary between the blank white areas and the flower it made me wonder if you had selected around the outside of the flower and then filled the selection with pure black to get rid of any irregularity/flecks or whatever in the background.

lightshipman said:
I was amazed really watching it happen as it is my first real attempt of this process, and a process I hope to use again in the future.
Click to expand...

It is magical, watching the picture building up. Wwhat you see during the processing depends on the stacking method being used, and presumably also on the software you are using. And when using a lot of images you get a good long slow look at the build-up.

lightshipman said:
I probably need to treat my other half to a bunch of subject matter ( flowers).
Click to expand...

:D
 
lightshipman said:
I will have another attempt at this and take note of the chromatic aberration issue.
Click to expand...

I don't think that is a serious problem. Affinity Pro should be able to remove it from the final image. (It's an interesting question, to which I don't know the answer, whether it would be better to remove the chromatic aberration in the individual images before doing the stacking. I don't think I'd want to do that with the number of images I'm using. Much simpler to remove it from the single, stacked image at the end.)

lightshipman said:
To be very honest with you this whole set up was done in about half an hour, I was home from work (dreaded 4 letter word), early, and just fancied taking a photo and having a play. The short days are very restrictive in that you run out of natural light, so things like this become rushed. The result of doing this excercise though has had a positive impact, that I want to do it again! Also I am very new to Affinity Pro, it has sat on my Mac book for about 18 months, not used, and I feel like getting more into it.
Click to expand...

The lack of light is tricky. You might try doing some experiments using flash - I find that practising with any old stuff that is lying around the place as subjects can be very helpful. If the final image is going to be worthless anyway I find it easier to concentrate on the technical aspects and not get sidetracked by trying to make it look good as an overall photo.

The desire to have another go at it ... that's good! I'm finding it a whole new area of close-up/macro to play around in.
 
lightshipman said:
Nick,
I have just been reading some of your
https://www.talkphotography.co.uk/t...ey-of-exploration.531050/page-17#post-7691787

Thread, I think you use a lot more images than I have done in your stacks. The orchids I have worked with were three image stack. I focussed by eye using live view on my Nikon D7100, and just started at the rear working towards the camera. I have been thinking of buying a focus rail, and increasing the number of images per stack.
Click to expand...

Over the past few years I've occasionally tried capturing sequences of images manually, but the amount of time and care needed was more than I felt inclined to give. So it was only ever an occasional experiment. One of the advantages of the Panasonic G80 I'm using now (and one of the reasons I bought it) is that the camera can capture a series of images which are focused at increasing distance from the camera. I've found that it can be practical to use this hand-held, depending on the magnification, the ambient light level and the ISO I'm prepared to use. As the magnification goes up, and the light level goes down, some support for the camera becomes more important.
 
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