Sharpness Issues

[Don Parsons]

I'm not getting the IQ that my setup should deliver. I'm using an Olympus BH2 polarizing scope with an Olympus 4X S Plan APO. My camera is a Canon 6D, and I use mirror lockup.
Looking thru the eyepieces the image is quite sharp, but when I'm trying to focus the image using Canon live view on my computer I just can't get the sharpness I want.
Hopefully there is a simple and inexpensive answer.
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[Pau]

Hopefully there is a simple and inexpensive answer

Maybe, but likely we need more info (camera settings, optical and mechanical camera coupling...) and maybe sample images

- Do you have enough microscope illumination?
If the microscope illumination is too low the LV image has lots of noise and this noise seems to move. The eye/brain combo is superior.
Do you have the same issue without cross pol? Are the pictures fine?

- Is your camera set at Silent Shutter mode?
If not, the shutter induces enough vibration to blur the images. In Silent Shutter mode you have EFSC and the only main vibration happens after the end of the exposure. Most modern Canon DSLRs produces a much lighter vibration at the beginning of the exposure but this is not going to blur the image with a 4X, I've tested the 6D at much higher magnifications directly coupled to the microscope with no issues.
This would affect the pictures but not the live image

- Do you have other sources of vibration at your studio?

[Alan Wood]

Don

Is your problem that nothing is sharp, or that only a limited area is sharp?

Depth of field is very small, even with a low power objective. For most subjects, you need to use a technique called stacking (or image stacking or focus stacking).

Take a series of photographs. Start just above the specimen, then change focus a little and take another photo, change focus a little and take another photo, and carry on until you are just below the specimen.

Then load the set of images into Zerene Stacker or Helicon Focus, and they will pick the sharp bits from each photo and combine them into a new image with everything in focus.

http://zerenesystems.com/cms/stacker
http://www.heliconsoft.com/heliconsoft- ... con-focus/

There is a phenomenon called diffraction that softens photographs taken through a microscope, so after stacking you need to sharpen your new image to compensate. Probably all photo editing software can sharpen images, just experiment until it looks right.

With EOS Utility software, you should not use mirror lock up. With Live View, the mirror is already up and the shutter is already open, and the exposure is started electronically. So there should not be any vibration until the shutter closes, at which stage it doesn't matter.

Alan Wood

[Don Parsons]

The images aren't as sharp as they appear in the eyepieces, I can't seem to get the same level of sharpness as I view. I have taken your suggestion of not using mirror lockup and it may have made a small improvement. I am quite familiar with stacking images, I use a StackShot and Zerene stacker for my high magnification photos of the scales on Lepidoptera wings.
I'l just keep trying different things until I get razor sharp images.
Alan, thank you for being a wonderful resource for Olympus scopes.

Don Parsons

[Don Parsons]

This is a sample of the problem I'm having in regard to sharpness. It doesn't have the crisp quality I want.

[rjlittlefield]

Don, is this the image you intended to post?



Please see the detailed instructions for image posting at http://www.photomacrography.net/forum/viewtopic.php?t=7 , especially noting steps 5 and 6.

--Rik

[Don Parsons]

Yes, that's the image.

[Tom Jones]

If it's just the monitor resolution you're using to focus, and not the photographs, it's probably because the 6D Live View resolution is 960 x 480. Pretty miserable compared to the view through the eyepieces.

http://breezesys.com/DSLRRemotePro/liveviewfinder.htm

I believe the 6D has HDMI output. You might try using that.

[Don Parsons]

I've never had a problem using live view on my Canon 6D. I have shot thousands of frames of Lepidoptera scale and stacked them with Zerene stacker and a StackShot. No problems.

[Tom Jones]

So what changed when you started having problems?

[rjlittlefield]

In the image that you posted, at the resolution that we can see, there are parts that look sharp and other parts that look blurred. I assume the difference between those is just a matter of focus with a non-planar subject. I also assume what you're concerned about is that the sharper areas in the captured image are still not as sharp as what you see through the eyepieces.

It would help a lot if we could see actual-pixel crops of the troublesome areas, since the exact appearance may suggest a cause. See https://www.photomacrography.net/forum/ ... hp?t=36168 if you have any doubt about what I mean by "actual-pixel crops".

--Rik

[Don Parsons]

I seem to be making some progress in resolving my lack of sharpness. Some of the problem is related to the position of the sub-stage condenser and the size of the condenser diaphragm. I'm continuing to make adjustments to the condenser and hopefully that will help with IQ.