Sawfly - First studio stack attempt

RichardF · Post by **RichardF** » Mon Jul 07, 2014 10:38 am

This is my first attempt at studio stacking photography that i am going to post on this forum. This forum has already helped me a lot with several aspects of this kind of photography like all the setups shown in several posts, and the lens tests.

The setup is a vertical setup and i used the following parts : Canon 5D, Nikon PB6 bellows, iris and mitutoyo 10x .
For lighting i used the Ikea Jansjo led lamps, 3 pieces of them and as a diffusor, i used a plastic hemisphere, cut off the top with a hole saw, and sprayed the inside of the hemisphere with white paint. (Thanks to Craig Gerard) link to hemisphere dome: http://www.photomacrography.net/forum/v ... 2fdccb5ea2

Image consists of 105 images combined in ZS PMax. Step distance is 8um.
The problem with this image is that i am not able to get the blacks of the sawfly black in the process of taking test shots to get the contrast right, thus before taking all the images. I am not satisfied with the contrast of the image.

The image below is a crop of the image above and just the part of the right eye is shown.

Looking at this cropped image, i see that a lot of detail is gone.
I think it has something to do with the lighting and the positioning of the lights, but i am not sure about this. For this setup the lights were positioned at 4, 6 and 8 o'clock.

All advise, opinions, input and critics are welcome.
My goal is to improve in studio stacking photography and hope someday i may get to the level of the pro's on this forum.

rjlittlefield · Post by **rjlittlefield** » Mon Jul 07, 2014 11:39 am

Looking at this cropped image, i see that a lot of detail is gone.

Yes. The blur is obvious even in the first image. You need to get this fixed before worrying about contrast.

The blur problem is not due to lighting. You have either severe vibration problems, or a damaged lens, or an incorrect optical setup.

One thing I notice is that you mention Mitutoyo objective and bellows, but nothing about a tube lens. Which Mitutoyo objective are you using? Exactly what do its markings say? How much bellows extension are you using?

You also mention an iris. What diameter is the iris closed to?

--Rik

Charles Krebs · Post by **Charles Krebs** » Mon Jul 07, 2014 8:11 pm

In addition to Rik's questions...

Is this the original 5D? If so what shutter speed were you using? Mirror lock-up? Good camera and still takes great pictures but nowhere near as vibration free as many of the more recent Canon models that have an electronic first shutter curtain.

RichardF · Post by **RichardF** » Tue Jul 08, 2014 10:48 am

Charles Krebs wrote:In addition to Rik's questions...

Is this the original 5D? If so what shutter speed were you using? Mirror lock-up? Good camera and still takes great pictures but nowhere near as vibration free as many of the more recent Canon models that have an electronic first shutter curtain.

Hi Charles, I am using the 5d Mark 3 and shutter speed was 1/6 sec. Mirror was not locked up during the stacking process and also i had no live view on.

I also ready your article about live view with an electronic first shutter curtain. (http://www.krebsmicro.com/Canon_EFSC/)
In the third paragraph you speak of "silent mode", this is where i am getting a little confused. After searching for more info on the internet and reading my camera manual, i read that my camera has a "silent" single shooting mode.
I have to change the drive mode to that "silent" shooting mode.

But when reading the live view shooting section of the manual, there is something what is called "Silent LV shooting" with 2 different modes.
In mode 1, the shooting operation noise is quieter than with normal shooting. And in mode 2, when the shutter button is pressed completely, only one shot will be taken. But then as long as the shutter button is down, the camera operation will be suspended till the shutter button is in it's halfway position, the camera operation is resumed.

This is probably where i got it wrong, i always thought that with "silent" mode, we were dealing with "silent lv shooting" mode 1 or mode 2. I have to change the drive mode to "silent" shooting mode, right ?

Rik wrote: One thing I notice is that you mention Mitutoyo objective and bellows, but nothing about a tube lens. Which Mitutoyo objective are you using? Exactly what do its markings say? How much bellows extension are you using?

You also mention an iris. What diameter is the iris closed to?

I am using the Mitutoyo Plan Apo 10x 0.28 f=200, see picture below. The tube lens is inside the Makro Extension locked by the screws. The tube lens is a Nikon MXA20696. In the picture you can also see the iris used, but i not know at what diameter the iris was closed to.

The picture below shows how the parts in the figure above are connected to the bellows i am using.

Rik wrote: How much bellows extension are you using?

Well, this got me thinking. How can i determine what the best bellow extension is ?
I read that for these Mitutoyo objectives, an extension of 200mm is required. That's what is shown of several diagrams posted on this forum and is stated on the objective (f=200).
So which steps can be taken to determine what the best bellow extension is ?
Do you take an image at different bellow extension lengths and determine where you get the sharpest image ?

Or are the alternative ways to get to the correct bellows extension ?

Thanks
Richard

rjlittlefield · Post by **rjlittlefield** » Tue Jul 08, 2014 11:32 am

Because your blur is uniform across the frame, I suspect that it's due to vibration. 1/6 second with no mirror lockup and no EFSC would easily explain that.

That objective and tube lens should give excellent sharpness except at the very corners of the field. See http://www.photomacrography.net/forum/v ... hp?t=23898 for illustrations using a Nikon D800E (36 megapixels, full frame).

Or are the alternative ways to get to the correct bellows extension ?

The simplest method is to remove the objective and, using the tube lens by itself, focus on some object a few hundred feet or farther away. That way the tube lens will be focused near infinity, which is its design point. As a crosscheck, you can compare against published specs for the tube lens. Results should agree to within a mm or so.

--Rik

Charles Krebs · Post by **Charles Krebs** » Tue Jul 08, 2014 5:26 pm

You definitely want to shoot from "live-view" and you definitely want to set either Mode 1 or Mode 2 in the live-view menu settings. Think in terms of a single shot until you let up on the release (Mode 1) or continuous exposures if you hold the release down (Mode 2). I generally use Mode 1 to avoid accidentally getting 2 or more frames at the same focus setting.

The "Silent Shooting" drives modes that are not associated with live-view is something completely different and not something you need here.

Shoot from live view (with either Silent Mode 1 or 2 set in the live view menu) and get the Nikon tube lens at "infinity" as Rik suggested and you will see a huge improvement.

RichardF · Post by **RichardF** » Sat Jul 12, 2014 3:55 am

Next image is the follow up of the settings and suggestions taken into account. Objective used is a Mitutoyo Plan Apo 5x and three Janso lights were used.
It a stack of 160 images and step size is 7 microns. Substacks of 6 images with an overlap of 2. Dmap only.

In photoshop only removed the dust from the eye part, no sharping has been applied yet.

During the substacking process i have adjusted the treshold several times and was wondering if this could have an effect on the overall result of the image ?

Live view is in mode 1 and Nikon tube lens focussed at infinity.
PS : something went wrong with the legs of this robberfly during cleaning, the dark circles at the lower right part of the image is where the legs used to be.

Part of the eye details:

Next step is to get a subject that has black in it and see if I can get the blacks blacks. This is something that i saw in the sawfly posting, the sawfly has black parts but they were not black. Conclusion just by looking at the histogram of the image.

I read some post about the lens shade (cylinder or cone, i do not know if a cylinder or cone give different results), this is the next test that i will we doing. Hopefully the dark part will be darker.

Any suggestions, input, ideas, opinions are welcome.t

Thanks for the support,
Richard.

lauriek · Post by **lauriek** » Sat Jul 12, 2014 6:10 am

I just want to say this looks soooo much better than the first shot! A great improvement..

And the legs thing, yeah I think we've all had that problem!

rjlittlefield · Post by **rjlittlefield** » Sat Jul 12, 2014 8:06 am

RichardF wrote:Next step is to get a subject that has black in it and see if I can get the blacks blacks. This is something that i saw in the sawfly posting, the sawfly has black parts but they were not black. Conclusion just by looking at the histogram of the image.

The first thing to do is set up as if you're shooting, then remove the camera and look into the back of the bellows by eye. Look around the sides of the lenses, adapters, tubes, and bellows for any reflections. Almost certainly you will see light coming from places other than the open part of the lens, and then you'll know where you need to flock and/or mask.

During the substacking process i have adjusted the treshold several times and was wondering if this could have an effect on the overall result of the image ?

Wherever the image goes "black in preview", those are areas where you've said that you prefer smoothness over attempting to retain detail. If there really are details in those areas, they are likely to be lost or softened. It's a balancing act. Often the best results are obtained by combining parts of the image produced from different settings of DMap and from PMax. See the "Advanced Retouching" tutorial linked at http://zerenesystems.com/cms/stacker/do ... rialsindex .

--Rik