Wood grain, 3rd pic added

rjlittlefield · Post by **rjlittlefield** » Mon Feb 25, 2008 7:47 pm

I was testing a new lens tonight, and rather than use the traditional moth wing, I thought I'd try something a little different.

This is end grain from a chunk of scrap wood, perhaps one of the local evergreens though I'm unclear about that. We're looking at part of a single tree ring, with the dark-colored summer wood at upper right and the lighter wood from next spring at lower left. The narrow bands slanting from upper right to lower left are radial rays, running perpendicular to the main rings.

Individual cells of the wood are clearly visible, and it's obvious what makes the ring structure: summer wood has small cells with thick walls while spring wood has larger cells with thinner walls.

The light regions between the cell walls are cell interiors. They are empty space in dried bulk wood but have been filled with sanding debris at the surface as I prepared the specimen.

I actually tried several different procedures, using various materials to impregnate the wood and fill the pores before sanding it. None of them gave the effect I wanted. In the end, what worked best was the simplest imaginable treatment: none!

So what you're seeing is just dry wood, sanded smooth with a progression of finer papers culminating in 1200 grit.

The lens is very nice -- sharp almost corner to corner and no CA that I can see. (Thanks for the tip, Charlie!)

I thought the pictures ended up pretty attractive and interesting also. Hope they sit well with you too!

--Rik

Technical: Canon 300D with Nikon CF N Plan Achro 10X NA 0.30 objective on 150 mm extension. Top image is about 70% of full field, rescaled to 800 pixels; bottom image is actual pixels. Stacked at 0.0002" to work around slightly imperfect alignment of the subject.

Edit: change title and clarify spring vs summer.

augusthouse · Post by **augusthouse** » Mon Feb 25, 2008 8:01 pm

Rik,
That is intriguing and interesting. There appears to be a smiling face in the first image. Wonder what caused that characteristic - top right, just where it should be for composition.

I can't stop looking at the lines - mesmerised. Such a distinction between spring and summer. Great subject.

If you still have the subject in place, how does the CF compare to the OM20 at 150mm extension? Does the OM20 begin to lose clarity at a certain point with regard to extension.

Craig

rjlittlefield · Post by **rjlittlefield** » Mon Feb 25, 2008 8:16 pm

augusthouse wrote:That is intriguing and interesting. There appears to be a smiling face in the first image. Wonder what caused that characteristic - top right, just where it should be for composition.

That's a hollow vessel of some sort, not sure what kind. The smiling face is just how the sanding debris happened to pack in. I liked the vessel and the pattern around it, but I didn't notice the face until you mentioned it.

If you still have the subject in place, how does the CF compare to the OM20 at 150mm extension? Does the OM20 begin to lose clarity at a certain point with regard to extension.

My OM20 doesn't begin to compare with a 10X microscope objective. See previous comparison shown here. This newer lens has central resolution that's very similar to the 10X NA 0.25 illustrated there, but the older lens has a smaller and more curved field, with noticeable CA.

--Rik

augusthouse · Post by **augusthouse** » Mon Feb 25, 2008 8:39 pm

Rik,
I want this on canvas and on my wall!

Craig

Mike B in OKlahoma · Post by **Mike B in OKlahoma** » Mon Feb 25, 2008 8:55 pm

Very impressive! Good subject well-executed.

Ken Ramos · Post by **Ken Ramos** » Tue Feb 26, 2008 4:53 am

This is impressive and very interesting. Wonder what I could do with the stereomicroscope, good project for today since it is raining out.

rjlittlefield · Post by **rjlittlefield** » Wed Feb 27, 2008 8:21 pm

Thanks for the comments, guys.

Craig, that is surely the most enthusiastic response I've ever received for an image from a lens test. Thanks for the email follow-up.

--Rik

Roy Patience · Post by **Roy Patience** » Wed Feb 27, 2008 10:04 pm

Rik,

Yet another superb image. The contrast and the patterns were stunning.

I am fascinated with the patterns in nature and, especially, in woods. One of my back-burner projects is trying to section wood samples for viewing with the microscope.

I have an interesting book that I found through the Quekett Microscopical Club that is full of practical advice on specimen preparation.

Roy

augusthouse · Post by **augusthouse** » Wed Feb 27, 2008 11:08 pm

Rik,
It is going to look great stretched on canvas and floating over a charcoal backing-board.

I showed the image to a few people. All were intrigued and I asked them to guess what they were looking at -they all had various interesting answers - and then I told them what it was and the actual size - while their jaw-dropped I was then able to go on and explain other aspects of it's 'story' as outlined in your post in regard to spring and summer... The smiling face completed the event. To me this is what it is all about and the reason why I originally became interested in photomacrography.

Let's talk about that CF. I have one with the following specs.

Nikon CF M Plan 10 MI 0.25 210/0

Does yours actually have CF engraved on the objective itself? Mine doesn't, but it does on the original Nikon container that it came in and was listed as a CF. The label on the container reads as follows: "CF PLAN MI 10x Discontinued"

The MI stands for "Interferometry, Noncontact, Multiple Beam (Tolanski)" as Charlie once explained to me. He translated the other specs and aspects related to my intended use.

Roy: That book sounds interesting. I was wondering about slices and backlighting and...and... and...

Craig

rjlittlefield · Post by **rjlittlefield** » Wed Feb 27, 2008 11:59 pm

Craig, it sounds like you've been having great fun with that image. You're right -- that's what it's all about!

augusthouse wrote:Let's talk about that CF. I have one with the following specs.

Nikon CF M Plan 10 MI 0.25 210/0

Does yours actually have CF engraved on the objective itself? Mine doesn't, but it does on the original Nikon container that it came in and was listed as a CF. The label on the container reads as follows: "CF PLAN MI 10x Discontinued"

Mine actually has nothing engraved on it. The markings are painted, and much of the paint has been worn off. The item was eBay 280200532261, titled "Nikon CF N Plan Achro 10x Microscope Objective" and described as follows:

The unique performance of Nikon CF (chromatic-aberration free) objectives is a result of Nikon's advanced technology in glass formulation and lens manufacture.

Nikon has pioneered multilayer anti-reflection coatings, computer aided lens design and unique extra-low-dispersion ED glasses with properties similar to flourite materials

Nikon CF N Plan Achromat Objectives offer the performance that was once associated only with Flour objectives. These objectives avoid the demerits of conventional Achromat objectives to ensure incredible image sharpness over the entire field of view. Superb resolving power due to higher Numerical Aperature (0.30) and high contrast are joined by excellent image-curvature correction, making possible ultra-wide field observation. Features 9.22 mm working distance. List Price: $608.00. Some of these objectives have cosmetic scratches on the outer case.

The labeling shown in the ad says only "Plan 10 / 0.30" and "160/0.17". That is consistent with what paint is left on mine.

Hope this helps. I'm sure that Charlie could give you more info about this beast, but I really can't.

--Rik

DaveW · Post by **DaveW** » Thu Feb 28, 2008 6:13 am

Even I like the pictures Rik and I am now fed up of looking at wood after being a carpenter for 51 years, you get less time in the UK for murder! Retirement this year thank goodness!

Great pictures!

DaveW

Charles Krebs · Post by **Charles Krebs** » Thu Feb 28, 2008 12:23 pm

Craig's "M" Plan is a "metallurgical" objective. Early ones were not CF, latter ones were. Unfortunately Nikon did not mark barrels of many of the latter ones with the CF designation. You need to have a product number or be familiar with the appearance of the mount. It is a "finite" type objective (no longer made) and needs 210mm extension to be at 10X.

Rik's is a "biological" objective... . 10/0.30 CF N Plan Achromat. It is also a "finite" objective, but requires 160mm extension to be at 10X.

Both have about 9mm working distance. They both do a great job on bellows. With my samples (My M=Plan is not the "MI" version) at a 10X magnification I'd give a slight edge to the 10/0.30. (Resolution is determined by the NA, which is slightly larger on the CF N... 0.30 to 0.25.

The "CF" part is very important as that is Nikon designation for objectives that are corrected for chromatic aberrations in the objective itself. Most objectives from this era were designed to be used with eyepieces that would provide final color corrections. As a result these "finite" CF can be good choices for bellows use. Working distance is an issue. In the "biological" objectives only the 4x and 10X have adequate working distance for bellows use. There were some LWD, ELWD, SLWD (long, extra-long, and super-long working distance) CF M-Plans made. I have a 20X ELWD and it produces quality images. But it is much harder to work with a bellows at those magnifications. DOF is a joke, and the stacks are usually more difficult to pull off as well.

Danny · Post by **Danny** » Thu Feb 28, 2008 9:52 pm

Well I'm not worried about what was used, but this is pure magic to see timber cells at this scale. Seen quite a few shots when I was going through an apprenticeship, but these are simply the best I've ever seen Rik. The most I remember was that parenchyma cells held the sugar...........I think

. I might have to do a google on it now.

Anyway, outstanding shots, exceptional lighting and very interesting from my point of view. Fascinating thanks.

All the best Rik.

Danny.

rjlittlefield · Post by **rjlittlefield** » Thu Feb 28, 2008 11:34 pm

Gosh, it's quite an accolade when even the wood workers think the wood works! Thanks, guys.

I'm almost afraid to polish up another piece, though, for fear the second one won't work as well as the first.

Ah, but that never stops the movie-makers, guess I won't let it stop me either.

Charlie, is there really any basic difference between a "metallurgical" objective and a "biological" objective, except that the biologicals nominally require a cover slip and the metallurgical's don't?

--Rik

rjlittlefield · Post by **rjlittlefield** » Sun Mar 02, 2008 10:55 am

After several confusing conversations on the subject of wood grain -- a couple of them with myself! -- I realized I needed to provide some more information to better explain the high magnification pictures that started off this topic.

What's shown here is an wider view of the wood around the earlier photos. The area outlined in black, at upper right, is what's covered by the first photo.

Hopefully this larger picture makes clear that the direction of growth is from upper right to lower left.

The transition from "spring wood" to "summer wood" is actually quite gradual, and is not what is shown in the first photo.

Instead, the first photo shows the end of one summer's wood, and the start of next spring's wood. That transition is very sharp, and corresponds to the times when the tree went dormant in the fall and started up again several months later.

I hope this is more clear -- at least now I understand it better!

I've tweaked up the text in the first posting to give a better explanation.

--Rik