New Macro Setup - Latest News

[georgedingwall]

Hi all,

I've now got all of the main bits and pieces for the new macro setup. The Nikon Lens/Pentax Bellows adapter arrived today from Hong Kong.

So I've now added a bellows and another set of extension tubes. The total length of the setup is about 50 cm from the front element of the lens to the sensor plane.

This is what it now looks like.


The field of view at the subject is now only 3 mm. Here's my first image with all of the bits fitted giving it's maximum magnification. I wont always be using this level of magnification, but I wanted to know what I could get.

This is also my deepest stack so far. The image was made from 100 frames with an adjustment of just 0.02 mm between each frame.



My setup.

Nikon D200 with 105mm Nikon Micro Lens
2 X teleconverter with 3 sets of extension tubes.
1/250 sec @ F8 ISO100
3 flash heads.
Home made focussing rail.
Stack of 100 images with 0.02 mm adjustment between exposures.
Stacked with Helicon Focus 4
Finished in Photoshop CS2.

[DaveW]

George

Trying to weigh up what the white stuff is. It looks a bit like dead skin peeling off. Also what looks like a mini woodlouse on the left hand side just above the eye?

DaveW

[georgedingwall]

Hi Dave,

George

Trying to weigh up what the white stuff is. It looks a bit like dead skin peeling off. Also what looks like a mini woodlouse on the left hand side just above the eye?

DaveW

It could be dead skin, if beetles have skin.

Under the microscope, it appears to be a translucent, almost crystaline, material. It is definitely peeling off, and it is over the eye as well. It has the impression of the facets in it. So it probably is skin, but could also be some some substance that has covered part of the beetle and is now wearing off.

The little woodlouse you spotted is actually just a bit of the skin substance which hs peeled off. Beetleman thinks this is a water beetle of some sort, so maybe this substance is something it picked up while swimming.

Fascinating image nevertheless.

[Carl_Constantine]

pretty impressive setup. What kind of lights are those, in particular, what is that center one?

Also, with a FOV of only 3mm and needing to adjust the focus by 0.2mm each pic, you can't really have a moving subject. I don't know that I could adjust the focus every shot of a subject (though that moth I took a pic of this weekend would have probably let me do it. It didn't move at all).

This setup definately takes patience, that's for sure, and lots of support for that extended lens setup.

Very cool Goerge, thanks for sharing.

[rjlittlefield]

George,

This is looking great!

A couple of comments...

1. Be sure to run a test sequence to determine optimum aperture for your lens. At this magnification, there's more than a factor of 2 difference in achievable resolution between f/8 and f/2.8 . (I'm speculating about how wide your lens goes.) With my Olympus Zuiko 38mm f/2.8 bellows lens, I get best resolution running it wide open.

2. Also test to see what your focus step needs to be. At this magnification and f/8, 0.02mm seems like a bit of overkill. My setup is similar to yours, and even at f/4, I get by pretty nicely at 0.001 in = 0.025 mm. So I'm thinking that you can either open wider and get more resolution at the same step size, or use a thicker step at the same f/stop. (Let me know if your tests indicate that this is wrong. I'm always interested to know where my thinking has gone wrong!)

Carl, you're exactly right that the subject has to be completely still. Some live subjects cooperate. Most of them don't. (See this article for examples. The subjects in figure 1-3 were alive, well, and potentially mobile, though they chose not to move while the stacks were taken.) Mark Plonsky uses a variation of stacking for live subjects under field conditions, but his technique relies heavily on manual editing of a few images. To handle the large number of images required for high magnification work, you really need a completely still specimen and a stable setup. Software like Helicon Focus can sometimes be used with a few images captured hand-held, but that's definitely pushing the envelope.

--Rik

[georgedingwall]

Hi Rik,

George,

This is looking great!

A couple of comments...

1. Be sure to run a test sequence to determine optimum aperture for your lens. --snip--

2. Also test to see what your focus step needs to be. At this magnification and f/8, 0.02mm seems like a bit of overkill. --snip--

--Rik

1. This was my first few test images with the new setup, so I just stuck with F8 as this is my normal aperture for macro shots. Now that I'm happy that the rig is stable and I can control it reasonably well, I will try stacks at different apertures and find which one is best.

2. The setup used for the Beetle Head shot was the maximum possible magnification I can get using my camera/lens/accessory setup. I just wanted to use the finest adjustment setting and see if I could get a successful image from a 100 frame stack.

I'm going to run this stack again, and exclude some images to see what the results are. I suspect I could get away with every second or third image. I did a test run on this image of just 20 frames with an adjustment of 0.1 mm, but it seemed to me that the facets in the eye were not stacked very well.

Now that I have a good stable system, I can experiment as much as I want with different settings. The chase for perfection is half the fun.

Bye for now.

[georgedingwall]

Hi Carl,

pretty impressive setup. What kind of lights are those, in particular, what is that center one?

Very cool Goerge, thanks for sharing.

All 3 lights you can see are the same. They are cheap studio flash heads bought from Jessops, (UK Camera Store). The 2 side lights have soft boxes fitted to make the light less harsh. The top light just has a diffuser fitted.

They are all fitted to lighting stands, and the top light uses a boom arm so you can position it directly above the subject.

The heads have 3 power settings, 1/4, 1/2 and full power.

I have another 2 smaller slave heads which I could use, and I also have 4 floods from an old copy stand which could be modified to use on my setup. There are lots of options.

Bye for now.

[georgedingwall]

Hi again Rik,

George,

This is looking great!

A couple of comments...

1. Be sure to run a test sequence to determine optimum aperture for your lens.

2. Also test to see what your focus step needs to be. At this magnification and f/8, 0.02mm seems like a bit of overkill.
--Rik

I went back to the original stack, and re-ran it using every 2nd, 3rd and 4th frame. I could see no difference with every 2nd or 3rd frame but the quality dropped way off using every 4th frame. So, all things being equal, at this magnification using F8 and adjustment of 0.06 mm would be sufficient to get a decent stack.

I also did a setup to test your other gem of advice - Which aperture to use. I set up a 4 mm screw using the same setup as before, but this time did two stacks using 0.06 mm adjustments and repeating the process for F4 and F5.6.

As you can see in the example below, the F5.6 stack, (upper image), has come out way better than the F4 stack.

Form these results, I would say that a setup of F5.6 with and adjustment of 0.06 mm gives me very good results when shooting at the maximum limit of my setup.

Does that make sense



Bye for now.

[Carl_Constantine]

Just one more question george, how exactly do you make a 0.06 adjustment? or 0.02 adjustment for the beatle shot posted here a while ago? are you adjusting in/out/up/down/left/right/all of these?

[georgedingwall]

Hi Carl,

Just one more question george, how exactly do you make a 0.06 adjustment? or 0.02 adjustment for the beatle shot posted here a while ago? are you adjusting in/out/up/down/left/right/all of these?

If you look at the setup image in the side on view, you will see beneath the camera a 2 axis engineers milling/drilling table.

This table has an adjustment capability of 0.02 mm in both axes.

When I'm setting up, I put the subject on the scissors lab jack on the right of the picture and position it so that some part of the subject is in focus. I may have to raise or lower the jack to do this.

Once I have the subject in the view finder of the camera, I can then center it in the veiwfinder, using the lateral axis of the drilling table and the Z axis of the lab jack.

When it's centered, I then use the longitudonal axis of the drilling table to fine focus on the nearest part of the subject that I want in focus.

Once I'm all set, I zero the micrometer on the long axis adjuster, and then I can start exposing frames. Between each frame I move the whole camera assembly forward by any distance in multiples of 0.02 mm.

If I wanted to move the camera forward by 1 whole millimetre, I would have to make one full turn of the adjuster. It has 50 x 0.02 mm index marks on it so you can be very precise. I measured the movement of the table using an engineers micrometer, and it is at least as accurate as the micrometer.

Hope this helps.

[rjlittlefield]

Form these results, I would say that a setup of F5.6 with and adjustment of 0.06 mm gives me very good results when shooting at the maximum limit of my setup.

Does that make sense

Sure does!

Since you're a push-the-envelope type guy (like me ), I'll mention a couple of directions that you might go from here.

The key to high resolution is finding a lens that works well at wide aperture. Most lenses degrade near their widest aperture, due to aberrations of various sorts. Apparently your current lens is like all the ones that I used to use, becoming sharpest around f/5.6-f/8. But there are lenses that hold up at significantly wider apertures.

Some of those lenses are made specifically for macro use, like the Canon and Minolta lenses that Charles Krebs used for his recent yellow jacket photos (1, 2) or the Olympus (Zuiko) bellows lens that I used for the weevil (1, 2). These lenses are a bit hard to find, and pretty pricey.

Another possibility is to reverse a conventional lens, say 50mm f/1.8. A really good one might peak out around f/2.8, which would give you twice the resolution you're getting now. (Unfortunately, most of these lenses peak out around f/5.6 - f/8, which would be no improvement at all over your current setup.)

Finally, you might consider using a microscope objective instead of a conventional lens. Microscope objectives have no variable aperture, so they're designed to run wide open, and that can be very wide indeed. The highest I've ever gone is using a 20X N.A. 0.40 objective, which is equivalent to f/1.25 . It's challenging to illuminate properly, because of the very short working distance (about 6 mm), but the results can be rewarding. (See my click beetle posts for examples.)

Enjoy that search for perfection!

--Rik

[georgedingwall]

Hi Rik,

Some of those lenses are made specifically for macro use, like the Canon and Minolta lenses that Charles Krebs used for his recent yellow jacket photos or the Olympus (Zuiko) bellows lens that I used for the weevil These lenses are a bit hard to find, and pretty pricey.

Another possibility is to reverse a conventional lens, say 50mm f/1.8. A really good one might peak out around f/2.8, which would give you twice the resolution you're getting now. (Unfortunately, most of these lenses peak out around f/5.6 - f/8, which would be no improvement at all over your current setup.)
--Rik

I think I might start with the reversing ring. I can pick one up cheap on ebay, and I have a couple of Nikon lenses that I can try with it.

I have the Nikon 50mm F1.4 and 35mm F2, which both have the same thread size as the ebay adapter. It's certainly worth a try as the lenses are just gathering dust at the moment. The only lenses I've had on my camera recently have been my macro lenses.

When I was looking for the reversing adapter, I also came across 3 auctions for the OLYMPUS OM ZUIKO BELLOWS F4 LENS you mention. One of them is 135mm and the other two are 80 mm. I can't figure out how to connect this to either my Nikon F fit camera or my Pentax M42 bellows. I can't find any adapters that would do the job.

How do you connect your lens to the bellows.

I think I'll leave the microscope lens option on the back burner for now. My head is spinning with all of the options that are available. I think I might just put the "Envelope Pushing" aside for the moment, and enjoy the photography.

Thanks for all your help.

[DaveW]

George

You could try Macro Nikkors if you can find any secondhand ones. Few know about these as they pre-existed the present day so called macro lenses that go from infinity to 1:1. The reason the Micro Nikkors got their name was because Nikon already had this range called Macro Nikkors. See:-

http://www.macrolenses.de/start.php?lang=en

You can navigate the database by the tabs on the top of the web page or this is the macro lens page:-

http://www.macrolenses.de/objektive.php ... f84997b0c5

The Carl Zeiss Luminars were always one of the most sought after of this type of lens.

If you cannot get adapters made there is always superglue!

DaveW

[rjlittlefield]

When I was looking for the reversing adapter, I also came across 3 auctions for the OLYMPUS OM ZUIKO BELLOWS F4 LENS you mention. One of them is 135mm and the other two are 80 mm. I can't figure out how to connect this to either my Nikon F fit camera or my Pentax M42 bellows. I can't find any adapters that would do the job.

How do you connect your lens to the bellows.

George,

For the high resolution work you want to do, I don't see any good auctions going on right now. You wouldn't want those f/4 Olympus lenses. Much better to get the 38mm f/2.8 or even better the 20mm f/2. Again, maximum resolution depends directly on what f/stop gives the best performance. A lens that does best at f/2.8 will beat one that does best at f/4, and one that's best at f/2 will beat f/2.8.

About your mounting question... I use an Olympus bellows, so mounting the Olympus lens on the bellows is no problem. Connecting the bellows to my Canon camera takes an adapter, but that was easy to build because the back of the bellows is just a smooth round hole. I already had an M42 adapter for my camera body, so I just machined a chunk of black ABS plastic to have M42 male threads on one end, a properly sized cylinder on the other, and some fine threads on the inside to block glare. See picture here.

By the way, regarding the Zeiss Luminars... I have a Luminar 16mm f/2.5 also. I haven't used it since I got the Olympus Zuiko 38mm f/2.8 . There's no compelling difference in resolution one way or the other, but I find the Olympus much easier to work with because of its longer working distance.

--Rik

[Charles Krebs]

George... looks like you are having fun, and getting great results!
Rik has provided great advice. A few random thoughts on things already discussed and a few new points.

When lenses are used far differently than intended, results are sometimes better if you try to return the "geometry" closer to that intended. Basically this means to try it reversed, as you have discussed. As set up now, you have a bit less than 500mm between lens back and camera, and a vastly shorter distance from the front to the subject. Reversing it returns the "geometry" closer to design parameters-- a longer distance from the front and a shorter distance from the rear. Also, if you really enjoy "tweaking" you can try different focus settings on the lens. When used "normally" the 105mm AF micro Nikkor uses "floating elements" to compensate for different focus distances. You are getting magnification via the large amount on extension, so changing the focus on the lens will not vary magnification that much, but it is possible that at a certain focus setting, the position of the internal elements might provide better quality. For example, if the lens is reverse mounted with enough extension that your field width is around 3mm, you might get slightly better results if you turn the focus ring to a setting that would (if the lens were used normally) provide a magnification of about 1:8 or 1:10.

You mentioned a few other lenses...
50mm f1.4 lenses are generally not too good for this type of work. I suspect you might get better results with your 35mm. (But when do this type of thing, the only way to know is to try)

The Olympus 80mm bellows lens is designed to be best at a 1:1 (1X) magnification. As far as bellows lenses goes, it is excellent, but there are others that have been specifically designed to be used at the higher magnifications you are using. They would be better choices.

For this work, I think a real "sleeper" lens that provides great results and is very inexpensive is the 50mm f2.8 El Nikkor (or a similar higher end Schneider or Rodenstock enlarging lens). The Nikkors go regularly for less than $50 on ebay. They should be used reverse mounted. Image quality is first-rate! 50mm enlarging lenses were typically (but not all) designed to provide best results on an 8x10 inch print from a 35mm neg. So when used reverse mounted they do really well in the 7X to 10X range.

Among good quality optics that work well for this use, you might find that there is not a huge difference in image quality. So much is limited by diffraction effects. Sometimes, as Rik mentioned, the decision will be based on working distance and the amount of extension required to obtain the desired magnification. (I will reinforce Riks point about aperture selection. Testing to find the best is critical. It is amazing how rapidly the image deteriorates if you close down too far. The "sweet spot" is really obvious when you look for it.)

A last thought would be possibly rigging some support directly under the camera body. The shorter the "moment arm" between the support and the shutter the better. Mirror lock-up is always used, but the shutter itself can cause some vibration. Most of the focal plane shutters used today are "vertical travel" so some support under the body (when taking horizontal images) can really help avoid shutter vibration. If your exposure times are around 1 second or longer is probably not necessary, as the vibration damps out rather quickly at the beginning of the exposure. But if you are in the 1/125 to 1/2 second range it can make a significant difference. (By doing a test where lights are dimmed to obtain a long shutter speed -- around 2 seconds-- and then comparing it to the shot with lights at normal settings, it is easy to test and see if this will help or not).

Charlie