Blurring around complex shapes

Shooting in macro mode, techniques, tips & tricks
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RemBrand
Posts: 1
Joined: 18.02.2022 22:11

Blurring around complex shapes

Post by RemBrand »

Hi all! Recently started playing with macro a bit more using my old Canon 50D and a wemacro rail. One of my hobbies are carnivorous plants which is my current subject to take pics off at the moment. When taking stacks of sundew plants, you have the lovely dew drops. Around these complex shapes there's a blur most of the time which I can't seem to get rid of whatever setting I pick. Any suggestions?
Cheers,
Remco
  • 51 stack
  • Canon 50D
  • 100mm macro lens
  • f2.8 - 1/40s
  • WeMacro rail with 100um steps via Helicon Remote
  • led lights
fuzzy.jpg
(301.06 KiB) Not downloaded yet
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PhilS
Posts: 32
Joined: 12.10.2020 21:41

Re: Blurring around complex shapes

Post by PhilS »

Hi Remcon,

I've spent a lot of time on this issue. But even so, I welcome others who are more knowledgeable about optics to correct or improve my answer.

The normal set up of a camera has the sensor fixed in place, and the lens moves when you refocus.

Distance to the image (Di) divided by distance to the object (Do) = Magnification

When you move the lens closer to the sensor to focus on the the farther object, Di decreases and Do increases. The magnification gets smaller.Apparently, HeliconFocus deals with this by changing images sizes to match the magnification. That's good, but it leaves a big out of focus foreground object next to the in-focus background in the faraway images. You end up with halos around near objects since you your faraway images have a big "shadow" of the nearby object blocking the in-focus far away object, and the nearby images have no in-focus pixels of the faraway objects.

I spend a lot of time and cloning background data onto the halos if they are annoying. I use some combination of the stamping tool and the spot healing tools in Photoshop.

See the images I am posting later today of the orchids for an example. Look at high contrast original and final, and compare the halos around the nearby leaves. It's not perfect, but it's a useful improvement.

Phil
Gregory
Posts: 2
Joined: 24.02.2022 22:15

Re: Blurring around complex shapes

Post by Gregory »

Hello Remco/Phil,
This is my first post. I agree completely with Phil on the Halos. It is quite frustrating. I was hoping to hear that Phil's Phase One would have solved the problem. What lens are you using, Phil? How are you advancing the setup? Is it the NovoFlex? I am working a number of different algorithms with no success yet. It has to be an Adaptive Interpolation. The only group that I have heard may be able to help after we use our Helicon is "Smart Edge", but I can't find out who owns it. It's not on the market yet. I know it is not Adobe.

I only photograph flora/grass. Mother Nature's middle name is Chaos. I have learned to smile, and I realize she will win most of the time, because I stack at least 200+ images into her final beauty. I adore the challenge.

Greg
Gregory
Posts: 2
Joined: 24.02.2022 22:15

Re: Blurring around complex shapes

Post by Gregory »

Hello once again Remco and Phil,
The concept of the halos is full of trade-offs. Could it be Blurring or maybe Alliasing? This seem to be similar to the complex nature of enlarging a photograph. Algorithms don't treat all pixels equally.

I decided to step away from the math for some experiments.

Light! I now only use macro flashes (2-4). Each can be calibrated to whatever the individual flower or grass tells me it needs. I then have found that the lower the better. Raising in Post. This improved the edge halo about 25%, if it is edge halo.

That led to 2 sleepless nights. Passive white reflection (small, 12"). The more the better. I need each of the 12" reflectors to have 100 tiny reflectors. You can probably understand where I'm going with this. I happens more with grasses or when there is a lighter object on top of a darker object. No body makes this type of reflector. I don't have time or the inclination to invent one at my age. It has solved another 25% of the problem.

I'm still not sleeping. So, decided to go crazy and really pump up the stacks. It has definitely helped.

I am still experimenting with all of these and other variables. Six more methods planned.

Enjoy,
Greg
shutterbug
Posts: 39
Joined: 17.12.2022 15:14

Re: Blurring around complex shapes

Post by shutterbug »

I know this is a year old thread but still:

If you have a lot of complex structures in the foreground and background you may want to use Method C (pyramid) instead of Method A or B.

Method A and B are great for flat surfaces without too many changes in dimensionality or rather geometrical figures. With complex overlapping, dimensional stuff Method C often gets better results, though the contrast sometimes suffers.

Personally I would suggest combining methods for the cleanest results and/or render the foreground and background objects separately and then combine them.You could even combine these rendered images again in Helicon Focus without resorting to Photoshop.

EDIT: as for the original image I would probably change your shooting parameters as well.
With a 100mm macro lens f 2.8 at 100um steps isn't quite necessary or beneficial unless you're shooting at 3x or 4x magnification and you're diffraction limited. At f2.8 you will have a very shallow DOF and that will cause a very sharp separation of foreground/background elements - which will make if more difficult to then stack them properly.
Instead you might want to try f4.0 or maybe even f5.6 - as a benefit you will need fewer images and your step size doesn't have to be quite as small.
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PhilS
Posts: 32
Joined: 12.10.2020 21:41

Re: Blurring around complex shapes

Post by PhilS »

Hello Gregory and shutterbug,

Continuing this antique thread. Sorry for not getting back to you soon.

I'll try method C, but I predict it won't help much because of the magnification issues I posted earlier.

Paraphrasing what I wrote in 2022:

As you move the lens closer to the object -- as when you focus on a near point -- the magnification increases. As you move the lens away from the object towards the sensor -- as when you focus on a far point -- the magnification decreases.

Consequence: Halos happen around nearby objects because the far-away in-focus pixels near the edge of the nearby objects are blocked by the in-focus nearby and larger objects.

The good news is I've found a new way to fix a lot of halos. With the combination of careful use of the lasso tool and "Content-Aware Fill", you can fake a lot of the halo into looking like the background.

Phil
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PhilS
Posts: 32
Joined: 12.10.2020 21:41

Using Content-Aware Fill on halos

Post by PhilS »

Example of Using Content-Aware Fill on halos

original draft image
https://www.dropbox.com/s/wxuy73g1igs4p ... y.jpg?dl=0

after two minutes of using Content-Aware Fill on the left and upper left halos:
https://www.dropbox.com/s/2z4zd3n0w57sl ... s.jpg?dl=0

A decent effect is sufficient for me in this image since I will darken the background to almost black and low contrast in the final image.
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PhilS
Posts: 32
Joined: 12.10.2020 21:41

Method B vs. Method C for fighting halos

Post by PhilS »

Method B, as I posted earlier today
/https://www.dropbox.com/s/wxuy73g1igs4p ... y.jpg?dl=0

Method C, as suggested by shutterbug
https://www.dropbox.com/s/c7gbdiiw1u42k ... y.jpg?dl=0

I was wrong. Method C is definitely better. Look at the left edge. And more interesting -- look at the horizontal curved line at the bottom of the top center large area. C made both of these better. Not perfect, but better in both cases.

I was wrong. shutterbug was right. C works better at decreasing halos! Thank you, shutterbug. I am switching to C for images like these!

Phil
shutterbug
Posts: 39
Joined: 17.12.2022 15:14

Re: Blurring around complex shapes

Post by shutterbug »

Hmmm well Phil you could also use Method B and increase the radius gradually and reduce smoothing until you're satisfied with the result.
That's a subject where I think both methods could work.

That too should prevent that sort of glow from occurring.
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PhilS
Posts: 32
Joined: 12.10.2020 21:41

Re: Blurring around complex shapes

Post by PhilS »

Thanks, shutterbug, I'll try that if I have the patience for the multiple experiments. As I was writing this note, my camera was making 76 images; each will be 907MB. Helicon Focus experiments take a long time. I am exploring getting a faster machine.

Phil
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