Mitutoyo 10X and 50X (need help with 50x)

leekekhuan · Post by **leekekhuan** » Fri Sep 11, 2015 5:14 am

Did some test with Mitutoyo 10X and 50X.
10X looks good but 50X is very soft, any advice what can i do to get better result with 50X.

Both taken with following setup

Raynox DCR-150
1/40, 100iso, mirror lock
.01mm set in Zerene stacker
Nikon bellows PB6
5D3

Mitutoyo 10X (un-sharpen except contrast and gamma fixed) - 144 clicks

Full Resolution
https://farm1.staticflickr.com/585/2069 ... 74bd_o.jpg

Mitutoyo 50X (un-sharpen except contrast and gamma fixed) - 45 clicks

Full Resolution
https://farm1.staticflickr.com/611/2113 ... dded_o.jpg

rjlittlefield · Post by **rjlittlefield** » Fri Sep 11, 2015 7:56 am

any advice what can i do to get better result with 50X.

Most important, try shooting with flash. That will freeze out most of the motion blur that may be coming from all sources, both environment and shutter. At 1/40 second you are currently in the range where shutter action alone can produce significant blurring.

Once you have the sharpness under control, you will also find that 0.01 mm is not a small enough focus step to capture all the detail that an NA 0.55 objective has to offer. To do that, you need more like 0.002mm or smaller.

--Rik

leekekhuan · Post by **leekekhuan** » Fri Sep 11, 2015 8:20 am

Thank Rik, tomorrow i am going to do second round. Will Zerene Stacker handle .002mm?
I remember you did a testing with Electronic shutter to get good result. May i know if Electronic shutter is better than Mirror lock?
EDIT
sorry forgot to mention, i was using flash at Manual mode 1/2.

rjlittlefield · Post by **rjlittlefield** » Sat Sep 12, 2015 12:12 pm

leekekhuan wrote:Will Zerene Stacker handle .002mm?

You mean as a StackShot step? Yes, that will work fine.

May i know if Electronic shutter is better than Mirror lock?

Electronic shutter is better than mirror lockup with mechanical shutter, IF you do not have environmental vibration. If you have environmental vibration, then flash is the only way to freeze that out, and you cannot use flash with electronic shutter.

It is hard to know whether environmental vibration is a problem, so I always recommend to start with consumer flash at low power, so that you get short flashes. Then once you know that the optics are OK, you can go back to working out any vibration issues with continuous illumination.

sorry forgot to mention, i was using flash at Manual mode 1/2.

For debugging the current problem, it would be better to drop the flash power to 1/16 or so, and do whatever else is needed to compensate for the reduced light. This is because the flash will produce much shorter pulses of light at 1/16 power than at 1/2 power.

Question: why were you shooting at 1/40 sec when using flash? I doubt that it affects the result, but I'm curious why not crank down the shutter to its minimum flash sync of 1/200 second or so.

--Rik

Lou Jost · Post by **Lou Jost** » Fri Oct 30, 2015 11:33 am

Rik wrote

you cannot use flash with electronic shutter

I was surprised to find my camera disabled its flash when the electronic shutter was enabled. I thought it was an idiosyncrasy of my particular camera brand, but your statement suggests it is a widespread limitation.

Is there some fundamental physical reason for this, or is it just that camera manufacturers didn't want to add a separate triggering circuit for the flash? If the latter, we could get around it by triggering the flash manually.

rjlittlefield · Post by **rjlittlefield** » Fri Oct 30, 2015 1:06 pm

Lou Jost wrote:I was surprised to find my camera disabled its flash when the electronic shutter was enabled. I thought it was an idiosyncrasy of my particular camera brand, but your statement suggests it is a widespread limitation.

Is there some fundamental physical reason for this, or is it just that camera manufacturers didn't want to add a separate triggering circuit for the flash?

The reason is a mystery. I am not aware of any fundamental physical reason. I have never seen a teardown or circuit diagram, to know for sure whether they would need to add another triggering circuit. My suspicion is that the required circuit is already present, and for some reason they choose not to use it. On the other hand, as far as I know EFSC+flash is not provided by the firmware hackers at Magic Lantern, so perhaps there really is some reason at the hardware level.

If the latter, we could get around it by triggering the flash manually.

That can definitely be done, but there are more devils in the details than you might expect. See http://www.photomacrography.net/forum/v ... hp?t=13726 for discussion.

--Rik

Lou Jost · Post by **Lou Jost** » Fri Oct 30, 2015 1:40 pm

Thanks for those links. Very strange. The camera I was referring to was a Panasonic FZ300, so this problem cuts across manufacturers. I think I can trigger a flash manually during silent exposure if I need to.