Please critique my plant photos

[Ysarex]

Edit: I tried again with different subjects. I'm really rotten at understanding exactly what I'm seeing in the monitor under such conditions. So I was a bit too close (smaller part of subject in frame) for the 70 focal length. But I think the result is still sound. If that had been correct, the effect would be slightly larger. As I would expect from my understanding of the theory, the background is most blurred for 28, 3.5, less blurred for 28, 5.6 and even less blurred for 70, 5.6

Yep, it's cold outside. So I shot it inside. I used a citrus tree we have indoors and focused on some leaves. You got to shoot both lenses at the same f/stop. I used a 21mm and a 100mm and took both photos at f/4. The out of focus background is blurry in both as it should be but because the background is so much larger in the 100mm shot the blur is enlarged and enlarged blur looks blurrier.

 

[mathbias]

I agree that your 100mm version has a blurrier background. I'll try to experiment more within the limits of my lens, to try to understand why our results are different. I'm confused about a couple aspects of your pair of photos.

1) The angles. I tried to keep about the same line of sight over a near-center part of my foreground subject to the background. I missed by a bit but not by a lot. Obviously off center things line up very differently, but near the center the line up is pretty good. In your photo the desk seems way too low in the far shot and/or too high in the near as if you were shooting downward in the near shot but level in the far shot. But I can't see that in the subject itself (the four foreground leaves). I can't work out what the change in angle did to the experiment. The experiment is more meaningful if the camera motion is along the same axis as the camera is looking (doesn't need to be level, just same).

2) The close background leaves aren't enlarged much in the far photo, which I think should mean they aren't much further away than the foreground. But they are out of focus. I don't understand how that happens. Further away somehow has less DoF?

 

[Ysarex]

I agree that your 100mm version has a blurrier background. I'll try to experiment more within the limits of my lens, to try to understand why our results are different. I'm confused about a couple aspects of your pair of photos.

1) The angles. I tried to keep about the same line of sight over a near-center part of my foreground subject to the background. I missed by a bit but not by a lot. Obviously off center things line up very differently, but near the center the line up is pretty good. In your photo the desk seems way too low in the far shot and/or too high in the near as if you were shooting downward in the near shot but level in the far shot. But I can't see that in the subject itself (the four foreground leaves). I can't work out what the change in angle did to the experiment. The experiment is more meaningful if the camera motion is along the same axis as the camera is looking (doesn't need to be level, just same).

I wasn't that careful. I didn't make measurements or calculations. I took the 100mm shot first and then tried to move the camera closer on a reasonably straight line. I just judged from the screen image size the distance for the 21mm photo -- same size image. When I got there with the camera I was high with the 21mm and rather than try and lower the tripod I just tilted the camera down a little.

2) The close background leaves aren't enlarged much in the far photo, which I think should mean they aren't much further away than the foreground. But they are out of focus. I don't understand how that happens. Further away somehow has less DoF?

I tried to focus both shots on the same place -- surface of the closer left side leaf. Probably should have used a smaller f/stop as DOF is pretty shallow at f/4. Because of the difference in the camera tilt the plane of focus is likewise a little tilted and not the same for both.

 

[mathbias]

I'm trying to learn a decent process for fairly narrow total angle panoramas, some of which will be plant photos. These would not look very different from just taking the same image either further away or less zoomed. But when examining the result on a computer it should be possible to zoom into more detail than would exist in the simple photo.

There are lots of different aspects to learn.

Today I had my first real alignment success with Hugin. I did multiple things different from past attempts. I'm not sure how critical each was, but each seems to be making at least some contribution to the improvement.
First panorama attempt with my 105mm lens.
First panorama attempt with the tripod accessories that I recently got for getting the axis of rotation more perfect.
First time in Hugin using the option to optimize all the parameters: the basics: yaw, pitch and roll, plus translate (correct remaining imperfections in the axis of rotation) plus several more that I don't understand despite reading the doc, some or all of which might be detecting and correcting geometric distortions by the lens (that I don't understand).

A short break in weather, slightly less bad for outdoor photography, let me rush out and take a few photos. That didn't give me time to try again for focus stacking (the Sony a7 doesn't do that for you and its manual focus design is aggressively user vicious making manual focus stacking far harder than it should be). I also forgot to check all the camera settings and messed up in managing my saved settings, so I accidentally wasn't saving Raw.

Anyway, in Hugin I just deleted several control point placed badly be the automatic process and added two control point. From there, everything was automatic. I can't see any hint of where the two seams are. I can't find any halos from imperfect sync in any in-focus parts of the picture. I can't find any flaws in the panorama construction.

In all past successes with Hugin, I never got near perfect alignment, so I was messing with masks to push the imperfect boundaries off of any subject details.

The full result is here. I don't have any good looking plant subjects at the moment. This one is extra ugly at the moment because I'm using posts and strings to bend it toward a better shape. But it was my best subject available today for practicing technique.

I really wish I had managed to get some photos taken to try mixing focus stacking with panorama construction. Hugin and associated tools do each of those but I can't find any info on combining them and my attempts before this have been total failure. Focus stacking needs really perfect alignment (that I never had before), while panorama doesn't typically have nor need quite that good. If the camera supported really good focus stacking, then two stages could make sense (focus stack and then build a panorama from the result). But with my camera, the two operations would need to be mixed together.

Here is a crop of one of the 3 images that made the panorama (so far as I can tell perfectly matching the same crop of the combined image) showing a place that really needed focus stacking: (I want the leaves slightly too far for this focus to be in focus, not the background even further out).

If I could have changed focus and taken the 3 shots again and still gotten the same great alignment, I think doing focus stacking and panorama construction together would work (but I still likely need to learn more advanced use of the software).

 

[weepete]

Glad you are starting to see results. Indeed I think this one is better than your first shot.

I don't think you should need to focus stack, just use a smaller aperture, and ballpark the DoF to cover the entire plant. Your acceptable focus extends roughly 1/3rd in front and 2/3rds behind your focal point, so focusing 1/3rd of the way in should get you good coverage. There are several calculators availible online for free, or apps that will quanify how deep your depth of field will be.

Don't worry about the background too much either. If your purpose is to document the progression of your plants, that's a different thing than fine art photography.

 

[mathbias]

Getting a sharper cutoff to the DOF still matters to me. I also what focus stacked panoramas when I take scenery photos on vacation, so I want to figure out the method.

For these very well aligned photos, I tried using just the focus stacking command rather than panorama merging, and still got the plant itself perfect (some serious problems with the sky that should be esy to fix once I understand what I did wrong). So I'm progressing slowly toward figuring it out.

 

[Lez325]

Plants = wide lens + small aperture

Sigma 70mm f2.8 ART lens and f2.8 - aperture - Enough said

Les

 

[weepete]

Fair play mate, if you want to find out how to do it just for the sake of knowing how that's cool. Just be aware that there's a simpler way to do it.

You may want to consider the angle you shoot from, as maximising the distance between your subject and background will also increase the amount of blur you get.

I had a brief look at the software you are using, looks a bit complicated to me. I just use lightroom and or photoshop to make mine and it's a lot simpler process. Might be worth considering some software that'll make this a bit easier to do!

I'd also suggest getting an indexing rotator, that makes it very simple to repeat your shots if you are determined to focus stack. Again, it's not really needed for landscapes unless you are extremely close to foreground objects, and normally you'd shoot them at f8-f16 to hit the sharpest spot on your lens, which maximises depth of field anyway.

 

[mathbias]

Plants = wide lens + small aperture

Sigma 70mm f2.8 ART lens and f2.8 - aperture

"small" aperture? Are we using the word "small" in the same direction? A small number for the aperture (f2.8) is a big aperture.

Once I have flowers again in my garden, I expect photos like that will be easier than before because of my Sigma105mm 2.8 Macro lens. With my Canon, I could never focus close enough. Similarly with the 28-70 zoom that came with my Sony. As you change the zoom, the minimum width field of view you can focus on doesn't change much (zoom to longer focal length increases the minimum distance away you need to be to focus).

Just be aware that there's a simpler way to do it.

I'm not convinced. Hugin and associated tools have poor documentation and a rotten UI, and take a lot of learning to figure out what you need to do. But comparisons I've seen online seem to show they ultimately are better tools.
Also, I'm a retired software engineer. The instructions for rebuilding Hugin and associated tools from source code are worse than the documentation for using it (a pile of out of date instructions most of which tell you to get critical libraries, tools, information, etc. from broken links). But I'll probably figure it out. I like the fact that if some feature really annoys me, I can go into the source code and fix it (such as the 200% max image zoom when setting control points).

If letting a program do the whole job did as good a job, that would be great. But these programs aren't that good. If you took pictures with an imperfect pano axis (even just a few pixels imperfect) and the program selects control points that vary widely in distance from the camera, then the alignment will be off and the best a "do it all" program can do is reduce the impact of the misalignment to modest halos on many edges. Now that I know which few clicks to use to get that behavior from Hugin (annoyingly not available in Hugin's easy mode) I could easily get near-zero-work results from Hugin that I'm pretty sure would match the low-effort results from purchased tools. If your photos are good enough, then your post processing doesn't need to be.

You may want to consider the angle you shoot from, as maximising the distance between your subject and background will also increase the amount of blur you get.

I have always considered the angle and its impact on the background. That also should be easier with 105mm 2.8 (small change in angle is a big change in background but the aperture can still be wide enough to avoid sharp focus on the background). But in many cases, no angle has decent background. In other cases (such as that shrub I did that test pano on) there are other considerations forcing the choice of angle.

I'd also suggest getting an indexing rotator, that makes it very simple to repeat your shots if you are determined to focus stack. Again, it's not really needed for landscapes unless you are extremely close to foreground objects, and normally you'd shoot them at f8-f16 to hit the sharpest spot on your lens, which maximises depth of field anyway.

A few pixels of yaw (out of a 4000 pixel portrait mode width) seems to be enough to wreck the idea of doing focus stacking before panorama construction (rather than during) and a few pixels of pitch or roll is even worse, and sideslip even worse. I don't think the ground is firm enough for an indexing rotator to solve that problem. If the camera supported focus stacking (zero touch between the shots varying focus) that would be OK. But taking the whole panorama at one focus, then the whole again at a different focus puts enough pressure on the tripod feet to compress the ground by more than the error I have in yaw when repeating the same positions.

Some landscapes do work simply by selecting a wider depth of field. My vacation photos often don't.

I still need to learn a lot more about enfuse and enblend (and maybe even modify their source code) to get a decent workflow that does focus stacking together with panorama construction. But I think I understand the theory well enough to know what software could do to get that right.

 

[weepete]

Well mate, I'm just trying to help you out a bit. It's up to you if you listen to the advice or not.

I've been shooting panoramas for the last 10 years, so I do know a little bit about how to set them up. Right now it seems like you are determined to plow your own furrow, so I'll leave you to it.

 

[mathbias]

I do appreciate constructive advice, even though I tend to question it. I may circle back to entirely taking some of the advice and/or it may influence what I do despite my not taking it as immediate marching orders.

 

[weepete]

That's cool mate, I'm an engineer too. Though I am mechanical by trade, I've moved into civils work wise. I don't mean any offense by my last post, just recognising that you are on a journey you need to folow, and you are determined to see that through. So crack on matey!

 

[Lez325]

"small" aperture? Are we using the word "small" in the same direction? A small number for the aperture (f2.8) is a big aperture.

Small as in NUMBER my f2.8 is the smallest number on the lens I used, but the WIDEST aperture

It seem to me you ask all the questions = then ignore any advise given by any member here ? Despite, in my comments on my image,
I actually quote part of the EXIF "Sigma 70mm f2.8 ART lens and f2.8 - aperture - Enough said "

I shall refrain from any future comments- as I feel I'm wasting my time & looking at your images you need all the advice you can get

Les

 

[Lez325]

Well mate, I'm just trying to help you out a bit. It's up to you if you listen to the advice or not.

I've been shooting panoramas for the last 10 years, so I do know a little bit about how to set them up. Right now it seems like you are determined to plow your own furrow, so I'll leave you to it.

Why bother Pete - he doesn't want to learn, pretty obvious to me fella

 

[ntz]

A lot of has been said ... I am not going to read it but in my opinion important things are concise and short .. and if I look on your photos there's just one foremost important thing:

Light is missing there ... everything else is secondary