Another Crazy Project.

[Don Hoey]

Experimental tabletop macro set-up Part 1

I have been a bit slack on the picture taking front so far this year. Lots of other stuff to do and then I got involved in another workshop project that is photography related, the results of which may be of interest to some. So here goes.

It all started in early June when I picked up a dead bumble bee in the garden, and had a good look at it with a workshop magnifier. Saw lots of detail I had never seen before like the hairs on its tongue. So the obvious question was how to photograph at sufficient magnification to show that level of detail without spending on more kit. A net search came up with a dedicated forum for this type of photography ........ Photomacrography.net. I found a thread detailing several set-ups ....
Link http://www.photomacrography.net/foru...pic.php?t=2825
Eeeek !!!!!! some serious cash has gone into most of those setups. Generally those guys are primarily using microscope lenses, also the final images are stacks between 50 and 100+ frames. All pretty daunting stuff, but even at lower magnifications a challenge I just had to pick up. Especially as I was not looking at spending anything like their budget. I was not sure how I would get on but I thought it would be an interesting exercise anyway. Last year it was Infrared on a budget, so this project could be this years photographic 'never done anything like it before' challenge.

I set an initial buget of £10 and make use of whatever I had around just in case the whole thing turned into a total disaster.

Starter was the base and that is from my old Phillips PCS2000 enlarger. To this I could attach stuff as I went along, and it could sit on the workshop bench as I cobbled bits together. First up was a precision slide for stacking and for this I picked on part of a swivelling vertical slide from my lathe. A mod to make the slide lockable and bolts to attach it to my Manfrotto sliding plate and I was off to the races.

Next up the subject table. I was looking for movement in 3 orientations, so I used the compound table from my bench drill ( workshop steadily being dissmantled ). To save the compound table scratching the enlarger base it is mounted on 4 rubber feet I bought in Maplins. Bolted to that is a vertical rising table to sit the subject on. This is the focus stage from my enlarger topped of with a bit of aluminium held in place by electrical tape.

I had to do a mod to my 1980's Panagor Auto bellows. In its native form this is not stiff enough to resist vibrations at high magnifications. So the front standard was drilled and tapped and the bellows attatched to a length of aluminium. The rear standard has the main fixing point and a groove was cut in the ally base to allow the front standard a degree of front rear movement before it is locked down. The bellows gave 150mm extension to which I could add a further 94.5mm using my Nikon PK12, 13 and PN11 extension tubes, and of course I could add a teleconverter for even greater magnification.

Next up was lighting, and for that I spent the last of my buget on a gooseneck microphone stand also from Maplins. As bought this was not stiff enough to support the flashgun so I inserted 6 lengths of fencing wire to stiffen it up. This is topped off with a ball head taken from an old Jessops mini tabletop tripod.

To test it I used a ballpen tip as the subject and a few things came out of that shot.
1) DOF is so thin that lots of frames would have to be taken for focus stacking and the micrometer collar on the slide did not have fine enough graduations as I might need to get to 5 or 10 microns.
2) Vibration. A major issue at these magnifications. My setup fell down in two areas. a) The Manfrotto Micro plate just did not tighten up sufficiently so would have to go. b) The bellows mounts are a cheapy aluminium jobs so did not provide adequate rigidity.
3) Getting the lens lined up and focused on the subject was another issue to be solved.

The story will continue as soon as I take some pics of the latest version ( still not quite finished ), but by now the spend has gone up to the dizzy heights of £117. Still I have spent so much time in the workshop I have saved more than that in petrol money.

Don

[andy153]

Carry on Don, this is very interesting - I wonder what the final budget will be though.

[robski]

Don £117 is a hell of a lot of blu tack, tin foil, card board and paper clips

But it sure look great - explains the long silence

[yelvertoft]

Welcome back Don. Good to see you haven't lost your spirit. Excellent project, keep it up.

[surfg1mp]

facinating read and project don! keep up the good work and i look forward to the next installment. Great looking rig by the way...

[Don Hoey]

Originally Posted by robski

Don £117 is a hell of a lot of blu tack, tin foil, card board and paper clips

Good one Rob.
This part shows where the money went.

Used Nikon PB-5 bellows + Nikon M2 ring, another Manfrotto long sliding plate, a shorter Maplins gooseneck microphone stand, one of two mini ballheads, ( taken from Hama mini tripods ) from London Camera Exchange in Norwich 'make us an offer' bin, and a bit of aluminium from the auto jumble at a steam rally.

Courtesy of Nikons statement that the PB-5 is not compatable with any digital cameras, and the fact that the mount was seized and slightly damaged I got this for a really good price . The M2 ring was thrown in with the bellows as I intend to permenantly sort the bellows mount problem by attatching it with bearing seal. As I cannot mount the D2X without it on the bellows as a spacer, its not a problem.

I guess Nikon declared the PB-5 as incompatable due to all the digital cameras having the handgrip which was absent on the Nikkormat's, F's, F2's and F3's so mounting can only be done in one orientation without the addition of a PK ring. The D2X just like any of the pro cameras, F5 through to D3X cannot move down the rail as the D100 can, due to the extra height from the battery box. In this case incompatable is not the same as useable with some additional extension. Ha,ha . To make up for some of that lost adjustment with the D2X I added an aluminium base and Manfrotto long sliding base.

Four pics attatched
1) D100 + PK12 ring mounted on the bellows to show available movement
2) D2X + M2 ring + PK12 mounted on the bellows. This shows how the camera cannot move down the rail. Also that the mount is now free to rotate for vertical orientation.
3) Closeup to show the damage to the lens locking pegs groove.
4) The head assembly including the new flash mount.

Don

[Don Hoey]

Precision dof stacking guide.

To overcome the problem of precision dof stacking I resorted to using workshop clocks otherwise known as dial guages. I have two of these. One with a max travel of 10mm with face graduations marked at 0.01 mm. The second unit is an imperial one with max travel of 1/2 inch with face graduations in 1/1000 inch. I just know my computer will struggle with massive stacks so they will do.

The clock stand is just a weighted steel base. The base is heavy enough not to move in use but easy to slide out of the way to set up focus on the front point . The base is then moved into position and the clock zeroed. A simple matter then to determine far focus by moving the whole camera/bellows/lens assembly forward using the chromed handle on the Myford slide. The total depth of the zone of required sharpness can then be read off the dial and some calculation made as to a suitable increment for each exposure. Move the slide back to the start position as indicated on the clock and snap away. The major advantage of using a clock as opposed to the micrometer dial on the slide, is that you do not have to take backlash in the slides leadscrew into account. Any movement of the slide will record on the clock.

Don

[Don Hoey]

Originally Posted by andy153

........... - I wonder what the final budget will be though.

This is probably the only area where I may spend a few bob. As can be seen in this shot of the reversed 50mm enlarging lens, it would be nice to have a 40.5 to 52mm adaptor rather than the electrical taped up job in this pic. Of course if I can get a couple of 40.5mm filters I will take out the glass and make my own adaptor. So I am not looking at spending that much .

For lower magnifications I have 105mm, 75mm and 50mm enlarging lenses, which when reversed should be excellent flat field objectives, while also being a lot smaller than camera lenses. Lots easier from a lighting front due to the smaller diameter as well. For larger magnifications then I will be into reversing 28mm and 24mm camera lenses.

Don

[Don Hoey]

The subject table.

This comprises the compound table used in the first version but makes use of the Manfrotto micro positioning plate for vertical movement. That is attatched via a ball head to a magnetic clock base. Lots of possible movements available there, even though I have added the second LCE bargain bucket ball head to carry the subject platform. Atop the mini-ballhead is a spigot to accept various holders so almost any subject orientation can be achieved. Albeit not expensively micro driven movements. Mounted to the table is the origional swan neck mic stand with a section of poly milk container for additional flash diffusion, and a device to hold a background card.

I have no idea of magnification factors so before the question is asked, I mounted a ruler in the subject position an checked how much will fill the frame on the long end with various combinations of lens and extension.

1) Maximum bellows extension plus the M2 ring = a total extension of 210mm
Reversed 50mm lens records 4mm
Reversed 28mm lens records 2.25mm
Reversed 24mm lens records 2mm

2) Adding PK12, PK13 and PN11 to that gives an extension of 304.5mm
Reversed 50mm lens records 3.25mm
Reversed 28mm lens records 1.75mm
Reversed 24mm lens records 1.5mm

Pics attatched
1) Subject stand
2) Subject holders to date
3) The whole set up in a single shot

The next post is the one dealing with subject framing, and in doing that I discovered another use for this outfit. Well chuffed with that one.

Don

[Peter Waites]

This is absolutely fascinating stuff Don. Please keep the instalments coming when you find time.