PDA

View Full Version : Need super bright LF lens for macro



aopie
12-Dec-2016, 14:12
I'm shooting extreme macro 4x5 tintype with a copy camera I've rigged up. It has 62" of bellows draw :). I'm working on achieving the range of magnification up to 20x (is the goal, more would be fine).

I have shot a lot of 4x5 and 8x10 tintypes mostly on a horseman 8x10 and have a bunch of lenses but nothing that will let me get as much magnification as I want AND be bright enough to work easily in this configuration.

I just bought a Nikon Nikkor 75mm SW - without thinking through how bright it would be - it's physically small and so at my extension it's a bit dim.

Does anyone have a suggestion of a physically large lens that would work for my needs?

Lenses I have to work with and have tried:
Ilex Optical 6 1/2 - great up to 8x
Schneider-Kreuznach 360mm - up to 3.3x
Schneider-Kreuznach 135mm Enlarger Lens Backward 4.5x
Fujinon W 250 - 4.5x - nice for smaller magnifications as well
Front Element Ilex Oscillo Paragon 75mm - up to 16x with possibly serious chromatic aberration, not yet tested

Ones I own but have but haven't tried yet
Ilex Copy Paragon 9"
Ilex Calumet Series 2 215mm
Turner Reich Anastigmat series II 8x10
Ross London 10" XPress
Ross Rapid Symmetrical 9x7

Thanks you,
Alexandra

Bob Salomon
12-Dec-2016, 14:22
A good reversed enlarging lens. Like the 50 mm 2.8 Apo Rodagon.

Dan Fromm
12-Dec-2016, 14:34
The relationship between extension (lens’ rear node to film) and magnification is e = f*(m + 1) where e is extension, f is the lens’ focal length, * is the multiplication operator and m is magnification. This is true for all lenses, regardless of pupillary magnification. When the lens is focused at infinity, m = 0.

For a symmetrical lens, with entrance and exit pupils the same size, i.e., pupillary magnification = 1, effective f/ number is f/ set * (m + 1) and the exposure increase factor is (m + 1)^2. Read f/ as “f over.” ^ is the exponentiation operator. So with a lens whose aperture is set to, say, f/4 the effective aperture when magnification = 1 is f/8 and, equivalently, the exposure increase factor is 4.

For a lens with pupillary magnification <> 1 mounted front forward, effective f/ number is f/ number set * ((m/p) + 1 ) where p is the pupillary magnification. With the lens reversed, effective f/ number is f/ number set * (1/p)*(1 + pm).

All of these relationships are well-known. Emmanuel Bigler, professor of optics and microtechniques at École Nationale Supérieure de Mécanique et des Microtechniques de Besançon recently derived them from first principles just to check.

In plain English, Alexandra, you're toast. At 20:1, for a symmetrical lens (many, not all, lenses for LF are approximately symmetrical) effective aperture will be aperture set * (20 + 1). Fast macro lenses for high magnification (think MacroNikkor, Luminar, Photar, ...) are no faster than f/2.8. 21 * 2.8 = 58.8. Sorry, toast.

Pere Casals
12-Dec-2016, 14:35
Does anyone have a suggestion of a physically large lens that would work for my needs?




Hello Alexandra,

I've a suggestion that I think is to work fantastic for your needs, I think: if you want to go 20x your filed of view has to be small.

This an SLR camera lens: Nikon 50mm f/1.8 , use it reversed, of course.

If you invert the lens... what was normally the field size it will be the negative size, so it vill cover well 8x10", and what was the negative size (24x36mm) it will be your field.

After focusing you can close diafragm in order to increase DOF.

The f/1.4 version may be less suitable because it has some distorsion and it is a tinny bit less sharp than the cheap f/1.8. Also you can use Nikon enlarger lens, EL-Nikkor 50N, as Bob says, the f/2.8 is the right one.

Best Regards,
Pere

Will Frostmill
12-Dec-2016, 14:46
Some people have had luck with reversed 35mm lenses. Working distance is very poor - basically flange focal distance, so for Nikon, 46.5mm. T-mount is 55mm, and Mamiya RB/RZ67 lenses are right around 100mm.

The field of view is going to be 24mmx36mm, (except for the Mamiya) so I don't know if your subjects are going to fit. But the angle of view directed toward the tintype is going to be as wide as the native angle of view, so you don't need enormous lenses.

You can get really nice macro lenses in those mounts for cheap. The Micro Nikkor 55/3.5 has a great reputation, and I think there's a 90/2.5 in T-Mount. I would also try a straight Nikkor 50/1.4, or especially a Pentax SMC 50/1.4.

aopie
12-Dec-2016, 14:51
Dan,

Ha! Toast. I usually operate best struggling against the limits of possibility....got myself there as usual. My math skills are so limited that I use online calculators, experience and testing to figure things out. Thanks for the plain English summary!

My understanding is that lenses with a certain aperture should give the same amount of illumination in spite of size but I don't find this to be true - that or the principle I think I understand is totally wrong. Working with 8x10 and long bellows extension it has seemed to me that the physical size of the lens does make a difference. I was hoping that someone knew of a 75mm lens that is huge that I could look for.

Thanks

aopie
12-Dec-2016, 14:52
I have a few and have used them for other macro work but find them too small - not bright enough in this application.

aopie
12-Dec-2016, 14:54
Will,

I have never tried any small or medium format lenses for this. I have a bunch of those I can try. I worry about size and therefore smaller illumination. Also working distance can get to be a real pain.

Pere Casals
12-Dec-2016, 15:10
Some people have had luck with reversed 35mm lenses. Working distance is very poor - basically flange focal distance, so for Nikon, 46.5mm. T-mount is 55mm, and Mamiya RB/RZ67 lenses are right around 100mm.

Just I've tested with the Mamiya RB67 Sekkor 65mm f/4.5. It looks great, two stops less bright but better working distance, as you pointed.

158623

Dan Fromm
12-Dec-2016, 15:27
Alexandra, magnification, slow emulsions and an apparent aversion to turning the lights up are what's toasting you.

A magic formula of some importance: Extension = focal length * (1 + magnification). Whence focal length = extension/(1 + magnification). You have 62" of bellows, you want to shoot at 20:1. The longest lens that will give you this has a focal length of 62/21 = 2.95" = 75 mm.

Will Frostmill made a good suggestion. A reversed 55/2.8 MicroNikkor AIS shot at f/4 will give superb results. At f/2.8, ok results that will be more than good enough for tintype. Will suggested a 55/3.5. We have one in the house but since I've never tested it I can't say much about how well it performs reversed at high magnifications. But I have tested our 55/2.8. Will is mistaken about image circle. It grows with magnification. Following Emmanuel Bigler's reasoning in http://www.largeformatphotography.info/forum/showthread.php?67361-Calculating-lens-coverage, at 20:1 a 55 mm macro lens for a 35 mm camera will cover 43 * 21 mm = 903 mm. That should be enough for you.

At 20:1 you'll need to use flash -- quite small flashes near the subject will do, so will hot lights at a greater distance -- or very long exposures. Focusing and composing may be a little difficult.

Do yourself a favor. You've asked a short apparently simple question that really needs a book length answer. Buy the book. Lester Lefkowitz' The Manual of Closeup Photography.

Pere Casals
12-Dec-2016, 15:30
Will,

I have never tried any small or medium format lenses for this. I have a bunch of those I can try. I worry about size and therefore smaller illumination. Also working distance can get to be a real pain.

What Dan says about effective aperture is the reality, enlarging x20 you spread photons in a large area... Also if you want a sharp result you'll end stopping diafragm.

So if you need more light then illuminate with more light, with a really powerfull light source (or flash for the shot). This is what it has to be done with microscopes to see something at great enlargements.

A Nikon f/1.8 will deliver near most brightness possible. A f/1.0 lens will not be sharp wide open. If you make x20 the light intensity it will be 400 times smaller. One full stop delivers 1/2 the light intensity.

So the thing has to be solved by strong light source.

ic-racer
12-Dec-2016, 15:49
Understand what Dan posted and realize diffraction is a function of the effective aperture. Therefore, consider the use of a smaller negative and camera. Enlarge negative to positive film and contact print that large negative to your alternative process of choice.

xkaes
12-Dec-2016, 15:55
You don't need that much extension to get that much magnification. Use a shorter focal length lens. For example, with a 12.5mm f2.0 lens you don't need much bellows at all to get to 20X. And if you increase the illumination you are all set. And a 12.5mm lens will cover 4x5 at that magnification.

THINK OUTSIDE THE BOX!!!

aopie
12-Dec-2016, 16:09
Thanks Dan,

I do have the book and it's been helpful as have your suggestions.

Dan Fromm
12-Dec-2016, 16:09
You don't need that much extension to get that much magnification. Use a shorter focal length lens. For example, with a 12.5mm f2.0 lens you don't need much bellows at all to get to 20X. And if you increase the illumination you are all set. And a 12.5mm lens will cover 4x5 at that magnification.

THINK OUTSIDE THE BOX!!!
Hmm. The grass isn't greener on the other side of the box.

More seriously, effective aperture is independent of focal length. Using a short lens instead of a long one saves extension at the expense of working distance. Can't have both. At 20:1, Alexandra is cooked regardless of the focal length she chooses.

Jim Andrada
12-Dec-2016, 16:27
Microscope????

Dan Fromm
12-Dec-2016, 16:35
Jim, a 'scope might do, there used to be 4x5 photo attachments for compound microscopes. I'm not aware of any for 8x10, but as we all know I don't know everything. But 20x is on the low side for a compound microscope. Maybe a good grade of dissecting microscope ...

faberryman
12-Dec-2016, 16:39
At 20:1 you'll need to use flash -- quite small flashes near the subject will do, so will hot lights at a greater distance -- or very long exposures. Focusing and composing may be a little difficult.
Ring light.

Pere Casals
12-Dec-2016, 16:52
Microscope????

Yes... with microscopes it happens same than extreme with macro when you attach a camera to the microscope (Nikon FX-35a... or DSLRs) you need powerful condenser illuminators, and much more because the X factor.

Pere Casals
12-Dec-2016, 16:55
Jim, a 'scope might do, there used to be 4x5 photo attachments for compound microscopes. I'm not aware of any for 8x10, but as we all know I don't know everything. But 20x is on the low side for a compound microscope. Maybe a good grade of dissecting microscope ...

Yes... 4x5 were quite common. Now it is cheap:

http://www.ebay.es/itm/Olympus-Microscope-PM-PB20-Camera-Attachment-PM-DLF-4X5-Filmback-PM-VS-3-Lens-/121769221900?hash=item1c5a02df0c:m:mFukjNnVeZgBkL8CZ-jqnqQ

Following rules, Olympus Microscope PM-PB20 Camera Attachment, PM-DLF 4X5 Filmback, PM-VS-3 Lens , $150

158624


Here digital improved a lot the results, as digital cameras are very convenient to make focus stacking and enhacing observation in this way. A lot of systems automate that, combined with multispectral captures and combined fluorescence excitation/filtration in confocal devices.

Anyway some velvia slides from microscopes are pure beauty !!

Bob Salomon
12-Dec-2016, 16:56
Jim, a 'scope might do, there used to be 4x5 photo attachments for compound microscopes. I'm not aware of any for 8x10, but as we all know I don't know everything. But 20x is on the low side for a compound microscope. Maybe a good grade of dissecting microscope ...

Linhof made a Micro Board in both 45 and 23 Technika sizes. Any camera that accepts a Technika 45 board can use it. It consisted of the board, 0 shutter and a short tube that will mate to ant society size draw tube. With this it would be easy to get an 810 camera mounted to a microscope as long as that camera, or an adapter board, accepts flat Technika 45 lens boards.

BTW, Linhof also made a Macro Board, this board, depending on when it was made, accepted either Luminar from 16 to 100mm or, after Luminars were discontinued, 39mm Leica thread mount lenses like the M Componon or Apo Rodagon-D lenses. It consisted of a flat board with a long tapered tube with a 0 shutter. Extreme magnifications of up to about 16x were possible, depending on focal length on a 45 Technika. The tapered tube was very important as it allowed getting lights in close to the lens without casting a shadow from the tube and shutter. These were usually used with cold light light systems like the ones from Kaiser and Zeiss.

Pere Casals
12-Dec-2016, 17:53
Linhof made a Micro Board in both 45 and 23 Technika sizes...

Very interesting information !

Randy Moe
12-Dec-2016, 19:37
Good to know why those extended Linhof lens boards are tapered. Seems obvious now. :) I used to use a stereo microscope to look for tiny cracks in steel rings at 100/1 then used the scope third port to 'snap' a video camera still that printed to a Sony 4x5 digital printer. Not Polaroid but some expensive commercial Sony gizmo. Called micro sections cast into resin, cut in half and polished. Lit from below with fiber optic tubes. PITA

Bernice Loui
12-Dec-2016, 23:43
Suggest spending some time at this web page regarding macro-micro photography.
http://www.savazzi.net/photography/default.htm


High intensity lighting with low heat can be accomplished by using a fiber optic light source (Kilowatts easily possible, specially with flash) with the light source at one end and fiber optic directly at the subject at the other end. Fiber optic ring lights in a variety of diameters and working distances are readily available.

At 20X, a proper microscope/microscope would be the better way. That branch of speciality has evolved specialty optical systems that work very well for that requirement. From optics to illuminate systems and more. One of the excellent 4x5 imaging microscopes from that time would be the Zeiss Untraphot system (Luminar was originally part of this system. Luminar was also used on Zeiss Universal and Photomicroscope) and the Leitz Aristophot. Zeiss Luminar & Photar were similar in optical imaging applications. Today there are specialty macro infinity correct, Plan, NIR, APO objectives made by Mitutoyo and others.


Bernice

xkaes
13-Dec-2016, 04:52
Let's not forget about Minolta's microscope lenses either -- which are basically Photars -- 12.5mm and 25mm. They have an RMS thread.

http://subclub.org/minman/macro.htm

vinny
13-Dec-2016, 07:12
get bigger lights

Bob Salomon
13-Dec-2016, 07:30
get bigger lights

Not bigger, much smaller cold lights on flexible arms that can easily get much, much closer to the object. Your way you would not be able to get most of the light onto the subject.

aopie
13-Dec-2016, 10:16
Thanks again all for this great information. I will look into the equipment you describe.

This has migrated from my question - which was really focused on achieving a particular setup for the hell of it - whether a good idea or not, to the best approaches. All of which are good information for me.

Thank you,
Alexandra

Myriophyllum
13-Dec-2016, 16:19
Hi Alexandra,

shooting 4x5" using a microscope and microscope camera is one of my favourite ways to get to negatives for alternative processes. Examples here:https://www.flickr.com/photos/136145166@N02/albums/72157676072065411.
I use a Zeiss MC63 camera with 4x5" back and a great Prontor magnetic shutter.
A magnification of 20x is on the lower site, a 2.5 (e.g. a Plan 2.5/0.08) lens could be used.
It sure takes some effort to get all the parts you need...
Greetings
Jens

Randy Moe
13-Dec-2016, 16:22
Very cool and that's LF!

Thanks for the link to your prints.



Hi Alexandra,

shooting 4x5" using a microscope and microscope camera is one of my favourite ways to get to negatives for alternative processes. Examples here:https://www.flickr.com/photos/136145166@N02/albums/72157676072065411.
I use a Zeiss MC63 camera with 4x5" back and a great Prontor magnetic shutter.
It sure takes some effort to get all the parts you need...
Greetings
Jens

Bernice Loui
13-Dec-2016, 23:23
Nikon has sponsored the "Small World" image contest for quite some years now. These are images made using microscopes and often complex microscope techniques.
http://www.nikonsmallworld.com/galleries/photo/2016-photomicrography-competition

Bernice

Pere Casals
14-Dec-2016, 03:47
Hi Alexandra,

shooting 4x5" using a microscope and microscope camera is one of my favourite ways to get to negatives for alternative processes. Examples here:https://www.flickr.com/photos/136145166@N02/albums/72157676072065411.
I use a Zeiss MC63 camera with 4x5" back and a great Prontor magnetic shutter.
A magnification of 20x is on the lower site, a 2.5 (e.g. a Plan 2.5/0.08) lens could be used.
It sure takes some effort to get all the parts you need...
Greetings
Jens


Great job ! I'll be following you in flickr, and asking...

Pere Casals
14-Dec-2016, 03:55
Nikon has sponsored the "Small World" image contest for quite some years now. These are images made using microscopes and often complex microscope techniques.
http://www.nikonsmallworld.com/galleries/photo/2016-photomicrography-competition

Bernice

Nice link !!!

Very complex works, some show combination of some fluorescence images and then focus stacking.

Also some captures seen in youtube are time lapse, one can see the different fluorescent channels, then focus stacking, and that for each frame of the movie, displaying cell division, etc.

This is digital advantage.

Anyway film captures have also a very special result.

aopie
15-Dec-2016, 22:19
Bernice, thanks for sharing that competition. Beautiful work there.
Here's an example of the look I'm working with these days
158737

goamules
16-Dec-2016, 11:50
Very nice Bernice, like the innovation and the art!