Focus stacking M1X - bracketing good, stacking broken

I got the hang of focus stacking on my E-M1 Mk.II, so went cheerfully ahead on the same lines with my E-M1X, enthusiastic about being able to stack 15 and not just 8 shots. The (poor) results surprised me, so dug deeper with some tests on the LensAlign hardware.

Used a 60 Oly macro lens at 2.8 and differential = 10 with the LensAlign target at 250mm from the focal plane. DoF with these settings around 2 mm. Here are the second and 15th shots, the others (shots 1, 3 to 14) quite nicely spaced between them:


Shot 2 has stepped forward to its maximum extent, about 6 mm in front of the nominal focus point.




Shot 15 has stepped back to its maximum, about 18 mm behind the nominal focus point.

The in-camera focus stack shows none of the range of focus from the 15 shots, as can be seen:


Resulting E-M1X in-camera focus stack, overall DoF around 7 or 8 mm.

Sanity check from Helicon Focus on the same 15 shots as below. The focus area is exactly as wide as the range from shot 2 to shot 15 gave (although we can agree that the bokeh is awful!).



Some good news is that the bracketing looks good, 15 nicely spaced shots. The algorithm for spacing seems to have changed a little, though, from the E-M1 Mk.II. First, it seems to me that a higher proportion of shots are taken in front of the nominal focus point, I'm guessing around 5 in front and 9 behind. With the 8 shots of the E-M1 Mk.II, it seemed that around 2 were in front and 5 behind. Second, the shots behind seem to have increasing spacing as distance increases, this wasn't so obvious with the E-M1 Mk.II.

I guess we'll be awaiting a firmware upgrade to get the in-camera stacking working properly with 15 shots....

--
Lester

Interesting find. Have you contacted Olympus to let them know of the problem?.

My initial thought is that the camera is taking 15 images but only stacking the first 8 of them (a la E-M1ii).

What happens if you stack the first 8 images in Helicon? Does it look like the in camera stacked image?

Did you try different interval spacing? Is 10 too big of a step. I use 3-5 for focus bracketing with my E-M5 MII.

****

Thanks for this report. A bit disappointing. Does the focus stacking still work correctly with eight photos? Is the problem confined to the choice of 15 photos instead of eight photos as in the past? Thanks, Joan

lester11 said:

I got the hang of focus stacking on my E-M1 Mk.II, so went cheerfully ahead on the same lines with my E-M1X, enthusiastic about being able to stack 15 and not just 8 shots. The (poor) results surprised me, so dug deeper with some tests on the LensAlign hardware.

Used a 60 Oly macro lens at 2.8 and differential = 10 with the LensAlign target at 250mm from the focal plane. DoF with these settings around 2 mm. Here are the second and 15th shots, the others (shots 1, 3 to 14) quite nicely spaced between them:


Shot 2 has stepped forward to its maximum extent, about 6 mm in front of the nominal focus point.


Shot 15 has stepped back to its maximum, about 18 mm behind the nominal focus point.

The in-camera focus stack shows none of the range of focus from the 15 shots, as can be seen:


Resulting E-M1X in-camera focus stack, overall DoF around 7 or 8 mm.

Sanity check from Helicon Focus on the same 15 shots as below. The focus area is exactly as wide as the range from shot 2 to shot 15 gave (although we can agree that the bokeh is awful!).



Some good news is that the bracketing looks good, 15 nicely spaced shots. The algorithm for spacing seems to have changed a little, though, from the E-M1 Mk.II. First, it seems to me that a higher proportion of shots are taken in front of the nominal focus point, I'm guessing around 5 in front and 9 behind. With the 8 shots of the E-M1 Mk.II, it seemed that around 2 were in front and 5 behind. Second, the shots behind seem to have increasing spacing as distance increases, this wasn't so obvious with the E-M1 Mk.II.

I guess we'll be awaiting a firmware upgrade to get the in-camera stacking working properly with 15 shots....

Click to expand...

Suggest you forward this to Olympus.

Peter 1745 said:

Have you contacted Olympus to let them know of the problem?

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Hi Peter

Wanted to float the issue first here, in case I was doing something wrong (smile).

Peter 1745 said:

What happens if you stack the first 8 images in Helicon? Does it look like the in camera stacked image?

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Not the first 8 images, but the middle 5, shots 5 to 9, give a result in Helicon that looks something like the OOC stack.

Digital **** said:

Did you try different interval spacing?

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Hi ****

Yes, tried my usual 3 or 4, similar issue, the full focus range of the 15 shots were not incorporated into the stack. My guess is only the middle 5 or 6 shots...

Digital **** said:

Is 10 too big of a step.

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I don't know that 10 is technically or computationally too big. Of course, the results are usually rather ugly, but in the E-M1 Mk.II the full range of front to back focus from the 8 shots was incorporated into the stack.

JoanKauai said:

Does the focus stacking still work correctly with eight photos?

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Hi Joan

The stacking still fails with 8 shots, but it isn't quite so obvious that the full focus range was not included.

Yikes! I tested the Focus Stacking feature on my M1X and it appears to work fine with the 12-40 PRO lens. I used the same parameters; just shot a ruler so nothing fancy. Focused on the "10" mark.


Lens set at 40mm F2.8; Focus Stacking 15 shots; Focus parameter at 10 (wide).


Lens set at 40mm F2.8; Focus Stacking 15 shots; Focus parameter at 5.

Looking at "Focus Stacking" on the specification page of the Oly web site, I notice that for the E-M1 MkII it clearly states,"8 shots are taken at different focus points and automatically composited together into a single image" yet for the E-M1X there is conspicuously no comment on the number of shots, so yes, it would seem there is something in the wind on this this.

OMforLife said:

Yikes! I tested the Focus Stacking feature on my M1X and it appears to work fine with the 12-40 PRO lens. I used the same parameters; just shot a ruler so nothing fancy. Focused on the "10" mark.


Lens set at 40mm F2.8; Focus Stacking 15 shots; Focus parameter at 10 (wide).


Lens set at 40mm F2.8; Focus Stacking 15 shots; Focus parameter at 5.

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Me too... set EM1X to optional 15 shots and great results straight up.

--
M43 equivalence: "Twice the fun with half the weight"
"You are a long time dead" -
Credit to whoever said that first and my wife for saying it to me. Make the best you can of every day!

BobT3218 said:

Looking at "Focus Stacking" on the specification page of the Oly web site, I notice that for the E-M1 MkII it clearly states,"8 shots are taken at different focus points and automatically composited together into a single image" yet for the E-M1X there is conspicuously no comment on the number of shots, so yes, it would seem there is something in the wind on this this.

Click to expand...

The E-M1X manual lists 3-15 shots. Olympus' latest marketing collateral in support of the E-M1X/E-M1ii that I picked up at WPPI also says 3-15 shots for the X. There isn't "something in the wind."

. . . Steven

OMforLife said:

Yikes! I tested the Focus Stacking feature on my M1X and it appears to work fine with the 12-40 PRO lens. I used the same parameters; just shot a ruler so nothing fancy. Focused on the "10" mark.

Click to expand...

Hi, er, OM

Good to try a different lens. I set up the LensAlign (ruler at a 30 degree angle) with my 12-40 extended to 40 mm at f2.8, around 10" from the sensor plane, and took 15 shots. I found that the M1X refused to stack, giving "Focus Stacking Error" until the differential was no more than 2, although it bracketed perfectly well. The resulting stacked image with diff = 2 looked perfectly plausible, as here:

[ATTACH alt="Result of a 15 shot stack, differential = 2. Nominal focus point "0", around 10" from sensor plane, 40 mm at f2.8. "]2154474[/ATTACH]
Result of a 15 shot stack, differential = 2. Nominal focus point "0", around 10" from sensor plane, 40 mm at f2.8.

The thing is, if I look at shot 2, the maximum forward (nearest) shot, the small "2" and "3" are well in focus, as below, but this does not show up in the stacked image, which only shows the smallest lower (nearer) "1" as in good focus.

[ATTACH alt="Shot 2 of 15, maximum forward focus point, smallest digits "2" and "3" in good focus, smaller "4" also OK. "]2154476[/ATTACH]
Shot 2 of 15, maximum forward focus point, smallest digits "2" and "3" in good focus, smaller "4" also OK.

Then, when I look at shot 15, being the furthest focus, digits "5" and "6" are nicely in focus with "7" OK, as below. However, they do not show in the stacked image, which only shows the upper (further away) smallest digit "1" in focus.

[ATTACH alt="Shot 15 of 15, furthest focus point, smallest digits "5" and "6" in focus, "7" also OK. "]2154477[/ATTACH]
Shot 15 of 15, furthest focus point, smallest digits "5" and "6" in focus, "7" also OK.

So the stacked image has failed to incorporate the range of focus taken in the 15 shots. Looking at the 15 shot series, just the three shots 5 to 7 seem to have been used to give me the resulting stacked image.

Could you browse through your 15 shot series and tell us if the focused areas in shot 2 and shot 15 show up in the resulting stacked image, please?

--
Lester

glassoholic said:

Me too... set EM1X to optional 15 shots and great results straight up.

Click to expand...

Hi, er, glass,

Could you browse through your 15 shot series and tell us if the focused areas in shot 2 and shot 15 show up in the resulting stacked image, please?

lester11 said:

glassoholic said:

Me too... set EM1X to optional 15 shots and great results straight up.

Click to expand...

Hi, er, glass,

Could you browse through your 15 shot series and tell us if the focused areas in shot 2 and shot 15 show up in the resulting stacked image, please?

Click to expand...

My apologies... you are right! I used my 60mm Oly macro at f2.8 and there is basically no difference between a 15 shot on step 5 vs step 10! On step 5, shot 2 and 15 appear to be used but on step 10, it is only stacking about shots 4 to 12. The individual frames on step 10 show the correct range vs step 5 but the extremes on step 10 are not stacked!

Single shot non stacking mode had about 1mm DOF, stacking with step 1 about 3mm, step 5 about 6mm and step 10 also about 6mm... but individual frames on step 10 covered about 14mm!

Definitely a bug here. It appears to work normally until you analyze the individual frames.

And as you say, coverage now is about 35% in front and 65% behind focus point whereas EM1.2 it was about 15% in front and 85% behind focus point.

--
M43 equivalence: "Twice the fun with half the weight"
"You are a long time dead" -
Credit to whoever said that first and my wife for saying it to me. Make the best you can of every day!

Lester,

As you can see, there is definite focal point movement. However, shot 2 is in the stack but shot 15 is cropped away. I wonder why you can't adjust the Stacking differential more than 2. Are your lens firmware up to date??


Shot 2 - Lens set at 40mm F2.8; Focus Stacking 15 shots; Focus parameter at 10 (wide).


Shot 15 - Lens set at 40mm F2.8; Focus Stacking 15 shots; Focus parameter at 10 (wide).


Shot 2 - Lens set at 40mm F2.8; Focus Stacking 15 shots; Focus parameter at 5.


Shot 15 - Lens set at 40mm F2.8; Focus Stacking 15 shots; Focus parameter at 5.

OMforLife said:

I wonder why you can't adjust the Stacking differential more than 2

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Hi OM

Turns out the lens was too close to its minimum focus distance. Although I placed it with the sensor plane around 260 mm from the target nominal "0", having read that its min focus distance is 200 mm, it thought that a differential of 10 across 15 shots would bring it closer than min focus, so refused.

I placed the target at 300 mm, and now the camera and lens are happy in that they will take 15 focus bracketed shots, each shot with the expected focus point moving forward and back and with the expected depth of field for f2.8. The stacking, however, fails. For larger differentials the stacked images have obvious artefacts, so that is known from before, but even with differentials of 3 and 2, the closest and furthest images of the 15 are not included in the stacked image. Happens with a bracket of just 8 images also.

OMforLife said:

Are your lens firmware up to date??

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Yes, 1.3 for the 12-40 PRO.

Blimey. Everyone complains that you can’t get shallow depth of field with m43 and then when they enable it...,.

I really find it hard to believe that Oly has produced something with such huge potential but has released it essentially half baked with little or no explanation or support. Having said that, I use it a lot and sometimes it's magic but more often than not, dam frustrating.

BobT3218 said:

I really find it hard to believe that Oly has produced something with such huge potential but has released it essentially half baked with little or no explanation or support. Having said that, I use it a lot and sometimes it's magic but more often than not, dam frustrating.

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It works, albeit the same as the EM1.2 with 8 frame stacking. I am sure it will be fixed soon with FW update. There is a possibility the algorithms are too quality focused... if the EM1X sees too many artifacts in the full 15 frame stack at step 10, it might be binning the extremes intentionally