Some trouble with stacking artifacts...

[etalon]

Hi Jörgen,

Ok, I'll try it tonight (I hope, I have enough batteries for the flash)

Cheers Markus

[ChrisR]

Shutter vibration can affect a flash picture, but at the 10x I think you're working, I doubt you would notice it.
If you get the flash power to be low, it might be 1/10,000th of a second or even much shorter. (That helps with the flash batteries, too!)

Yes, rear-curtain in a darkened room will help ifyou are using longer duration flash (some studio flash is 1/300th second)
About shutter life -I haven't seen numbers for shutter life of the mirrorless cameras. I don't know af any which are completely electronic shutters (apart from video). (Maybe I saw something about one announced recently??) .

an unusual combined effect.

Well you have some or all of
- the usual stacking artifacts from overlapping details giving
- - halos,
- - transparent foreground and
- - "glowing" Pmax highlights ,
- perhaps(p) the perspective-shift-with-focus problem (unusual with a Mitutoyo 10x because it's close to telecentric).
That would be enough, but also
- an unusual jagged appearance in a few areas
- unusually blurred stack results
- assymetric affects.

That's quite a collection.
Hence, the suggestion of very diffuse flash to try to remove some of the usual troublemakers, and see what remains!

Later we shall be quoting from Shelock Holmes, but now, is really premature

"Sherlock Holmes: How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?"

[mawyatt]

Markus,

As Chris mentioned strobe exposure can be slow compared to speed lights, as slow as 3 milliseconds. I have many strobes that illuminate the setup and are triggered with RF triggers and optically (flash). So this can smear the exposure even longer, although I don't know long.

One of these days when I get some time I want to measure the flash duration of my strobes and speed lights as well as the timing relationships like delay from camera to flash peak with sync cord, RF and optically triggered.

So for now I just use the rear curtain camera sync via the hot-show RF trigger which triggers a single (or 4 in some cases) strobe which then optically triggers the other slave strobes. This has worked OK so far, but I am sure there is room for improvement.

Good luck and keep us posted on your progress.

Best,

Mike

[etalon]

Good afternoon, gentlemen.

Now I have the results from my flash-test

The test parameters are as follow:

All pics are ZS DMap stacks. They are 100% crops from all corners and the middle. Acquisition time with continuous light was 1/160sec.

With flash, acquisition time was 2sec, flash on the 2. curtain. Flash power was as low as possible.

All light sources was well diffused.

And here the results:

Mirror lockup, 10sec delay to the shots, continuous light


EFSC, 10sec delay to the shots, continuous light


Mirror lockup, 10sec delay to the shots, flash


EFSC, 10sec delay to the shots, flash



My conclusion:

The best result give EFSC with flash, but also with flash it seems, the lower left corner suffer quite a little bit. But, because this was always the first shot, it may be a bad focussing by me...
Well, shooting with flash is sadly no possibility for me. So I´ll try to improve the mechanics to avoid vibrations through the shutters of the camera. Further I´ve ordered yesterday a Olympus Em5 mk2 camera. We will see, how that improve the results.

Thanks for your help, guys!

Cheers Markus

[ChrisR]

EFSC with flash,

Did youyou use external timing/electronics to fire the flash? If you connect a flash to the camera, it disables EFSC.

[etalon]

I made it with Canon utility on my pc. There you can do the settings for the flash and when you use the live view window, you can do a testshot with flash and save it. So I do remote controled a testshot, drive the unit a step (also remote) and after a 10sec delay I made the next testshot... It seems to me as it work like in EFSC mode.

[JH]

Hi Marcus

When I take pictures I set silent mode (1 or 2) in camera if I want to use continuous light – if I want to use flash I disable silent mode or else the flash won’t work.

Regards Jörgen

[etalon]

Hi Jörgen,

yes, I do the same. But, as you describe, if you want to use the flash while using silent mode, you can do it like I describe it above. But it's very circumstantial, so it's ok for a test, but I don't want to do that for a huge stack...

Cheers Markus

[rjlittlefield]

But, because this was always the first shot, it may be a bad focussing by me...

It is good practice to shoot a few extra frames on each end of the stack, to avoid the possibility of starting too late or ending too early. Trying to start and end exactly on the correct points introduces a risk of wasting the whole stack, just to save what is literally a few pennies worth of shutter activations.

It seems to me as it work like in EFSC mode.

That's probably an illusion. When you run with Canon flash in what would otherwise be EFSC mode, the camera realizes that there's a conflict and automatically pops back into normal mode just long enough to take the picture. You could see for sure what's happening if you set a long shutter time, like 1-2 seconds, and run the test while looking into the front of the camera with optics removed.

I´ve ordered yesterday a Olympus Em5 mk2 camera. We will see, how that improve the results.

We will be very interested to see the results. It would be even more interesting to see the results after having heard the shooting, but of course we will have to rely on you for your impressions of that. Ideally the camera will make no noise at all when each shot is taken.

--Rik

[etalon]

It is good practice to shoot a few extra frames on each end of the stack, to avoid the possibility of starting too late or ending too early.

Yes, normally I do that. Know the vulture why I didn´t it in the test...

That's probably an illusion.

No. You can hear it very clearly, what kind of shutter action in a 5D2 happens... But I did the test for you (which you mentioned) and it is exactly as I describe it above. You can make pics in silent mode with a Canon flash while using Canon utility software. But it is really manual work
If you are an owner of a Canon EOS with silent mode, you can easily do that test as well and we can compare our experience.

We will be very interested to see the results.

Me too!

Cheers Markus

[ChrisR]

I wouldn't be entirely surprised if there is a difference, between some cameras. My Canon EOS 600D doesn't behave exactly like some T3i cameras, in one or two minor respects.

Quite surprised, on EFSC + flash, though . Does it only work on rear-curtain sync? At any shutter speed?

[JH]

Hi Marcus

You have very good testing skills and a good testing target. It will be very interesting to see your results with a camera with a fully electronic shutter.

If you have time it would be interesting to know if there is a short enough shutter speed to eliminate the “EFCS” vibrations. A longer shutter speed will of course work but then there starts to be problems with all sorts of other sources of vibration than the shutter.

Regards Jörgen

[rjlittlefield]

That's probably an illusion.

No. You can hear it very clearly, what kind of shutter action in a 5D2 happens... But I did the test for you (which you mentioned) and it is exactly as I describe it above. You can make pics in silent mode with a Canon flash while using Canon utility software. But it is really manual work
If you are an owner of a Canon EOS with silent mode, you can easily do that test as well and we can compare our experience.

Interesting -- thanks for the clarification. I was not aware of that behavior in the 5D Mark II. My camera is only a Canon 500D, which does not have that feature.

So then getting the sharpest results with silent mode and flash does continue to suggest that your problem is with vibration. Because your EFSC result with continuous light is not as sharp as EFSC with flash, it seems like some of the vibration is probably environmental. That could be helped with isolation, such as Sorbothane feet under that breadboard.

--Rik

[etalon]

Does it only work on rear-curtain sync? At any shutter speed?

Chris, I don´t know, because I have only tested the settings which are reasonable for my test.

if there is a short enough shutter speed to eliminate the “EFCS” vibrations

Jörgen, thank you
Well, my vacation ends today, so I have to go back to work tomorrow, but if I have a little bit time, I will do that for you. But, I don´t think that it´s necessary to know, because for a good S/N, the ISO should be as low as possible. The amount of light is like it is, and the only possibility to do adequate acquisitions is to change the exposure length (or using more light, but this is in the most cases not possible). Therefore I think it´s important to have a setup, which can handle all exposure times without vibrations...

it seems like some of the vibration is probably environmental. That could be helped with isolation, such as Sorbothane feet under that breadboard.

Rick, maybe you are right, but I´m not sure. Normally, when external vibrations occur, I would expect that the whole sensor is affected. This is also what I would expect when intrinsic vibrations occur, because the sensor itself is a very stiff piece, which should vibrate as whole unit. So I don´t understand what happens in my case, where only parts of the pic are unsharp. Maybe it is a kind of tilting the sensor while the torque moment of the shutter motors affect the sensor board in the time of shutter action... I don´t know it, but because of the very small DOF, some micron would be enough...

I think about to build up the entire setup on my big main breadboard. This should prevent external vibrations. But handling is on the small breadboard better. As I wrote above, I don´t think of external vibrations... Well, we will see what happens with the new camera.

Cheers Markus

[Saul]

If you have Iphone or Android phone , you can use Sensors Kinetics app - you can see all your vibrations easily - after playing 5 mins with this app, I bought Pro version immediately, it helped to solve my remaining problems with vibrations . Even more - I could adjust my delay times in my PLC according real data - it means my stacking process became shorter.