Category Archives: Photography

Gossen Luna-Pro F

Film

Handy.



Small it is not. Compare with the
Reflx meter in the camera’s accessory shoe.

Go to B&H and you will find no fewer than 51 hand held Gossen exposure meters listed. Gossen has been making light meters since 1932. Its major West German competitor was Metrawatt which made the various Leicameters and was absorbed by Gossen in 1992. You can view the full history here. And to this day you can blow upward of $2,000 on a fancy Gossen spot meter.

But there’s no need to spend that sort of money if all you need is a reliable, hand held workhorse.

My Gossen Luna-Pro F ran me all of $56 shipped, and arrived in mint condition. No case, but you really do not want one. It’s just one more time delay factor in the field.



The Luna-Pro F.
The green button is for checking the battery.

The meter was first sold in 1981 and is the last mechanical pointer meter made by Gößen, along with the SBC (scroll to the end). Now that’s retro.

You can download the user manual here and it’s an education in light measurement and beautifully written. I highly recommend reading this manual as the Luna-Pro F is a sophisticated, relatively complex instrument and repays a thorough understanding. Unlike its famed predecessor, the ultra sensitive Lunasix, the Luna-Pro F uses a regular 9 volt battery, not the discontinued dual 1.35 volt mercury cells used by the Lunasix. (The above Leicameter link will tell you all there is to know about the use of modern cells in meters which require 1.35 volts). Not that the sensitivity of the Luna-Pro F is poor, as it goes down to -8EV, which is ‘black cat in a coal cellar’ territory. -8EV is 16 minutes at f/2 with ISO100 film! Further the light sensor is a Silicon Blue cell, not the Cadmium Sulphide one used formerly. That mean that the CdS cell’s over sensitivity to the red spectrum is gone with a color response similar to that of the human eye. And of film.

Before inserting the battery take a look at the position of the meter needle. It should be centered over the small mark just to the right of the word ‘Under’ in the meter’s window. If it is not use a jeweler’s screwdriver on the screw in the back to adjust it. The battery must be disconnected. Connect it and the reading will change.

The battery compartment is well insulated from the internals of the meter so in the event of a battery leak there should be no damage to electrical components. The battery is a tight fit, so dress the two wires at the side of the battery, not underneath, to ease replacement of the sliding cover.

To test the battery, depress the large red meter reading button at left then depress the small green one at right. Mine needs a committed push. With a fresh cell the meter’s needle will move well past the right of the ‘Batt.’ inscription in the meter’s window.

Measuring 4.75″x1.75″x2.75″ the Luna-Pro F weighs 8.6oz/245grams with battery and lanyard. It will also measure flash exposures when the small mode selector switch at left is in the raised position. The coverage angle is 30 degrees for reflected light readings which is like a 90mm lens on the camera. Slide the white cone in front of the cell and the acceptance angle becomes 180 degrees for incident light measurement. The large red switch at left is depressed to take a light reading. Depress and turn it clockwise and the meter goes into continuous reading mode, switching off after 30 seconds to conserve the battery. Mine turns off exactly 30 seconds after taking a reading – there’s that famous German sense of humor at work for you.



The factory label was AWOL in mine, so I added an explanation.
When the smaller button is ‘out’ (right image) the meter will measure flash.

If you are seriously off your rocker you can even procure a tele attachment with a viewfinder which narrows the measuring angle to 15 or 7.5 degrees:



The Gossen Variable Angle attachment.

There’s a host of other attachments – one for microscopes, one with a fiber optics probe, one for copying and finally, for the seriously deranged, an Enlarging Attachment if you are seeking to emulate that darkroom doper and serial over-processor Ansel Adams. Funny cigarettes are extra. Come to think of it, AA would have benefitted from that attachment. Naturally Gossen thought of everything and has included Zone System settings for all the Zonies out there.

You see, those humorless Germans decided that this light meter would be a system not some poncy toy for poseurs.

Putting aside this insanity the core instrument is a delight to use. Unlike most meters which indicate a reading from the galvanometer needle, the Luna-Pro F uses a ‘null reading’ design. After taking the light measurement you rotate the large dial until the needle is centered, and all the resulting shutter speed/aperture combinations are easily seen. Want to overexpose a stop? Or two? Or three? Simply rotate that dial until the needle points to +1, +2 or +3. It’s the same for underexposure, with the needle the other side of the ‘0’ mark. (There are small 1/3rd stop dots between the major intervals for obsessives).

Simple, elegant, uncluttered, with nothing left to chance. How a machine should be.

And that rotating dial is big and bold, leaving no doubt as to the result. While there are scales for ciné and all sorts of funky corrections, these are about as useful as the markings on the rotating dial on your overpriced sports watch. No one understands them and even fewer use them. These are yours to disregard.



A null reading. What could be simpler?

One beauty of the null reading design is that once you have established a mid-tone reading you can point the meter at the lightest and darkest areas of your subject, take light readings of both and immediately see what the exposure range is based on the +/- reading of the needle. With slide film, for example, where over-exposure is a killer, you may want to elect to under-expose, based on what those readings tell you, recovering shadows in post processing.

Battery life? I have no idea but suspect it’s huge. Those 9 volt cells pack a punch. And there’s a battery check function to tell you how it’s doing. And you can probably even find this battery in sub-Saharan Africa. It’s the same one used in your home’s fire alarm.

The Gossen Luna-Pro F is the last hand held meter you will buy, with mint used versions under $60 representing one of the great photography bargains. While listings for the predecessor Lunasix are much more numerous there really is no need to go there with all the related battery problems. Some patience and a Luna-Pro F will turn up. (The meter is known as the Lunasix F outside the U.S.). Later digital versions? Oy! Digital schmigital. Humans are analog beasts. This analog device pairs nicely with your retro film camera whose meter died long ago.

Don’t get caught out: There’s an Exposure Factor adjuster (for things like filters) on the dial’s outer periphery:



The hidden EF adjustment – the setting is circled.

You want this set at ‘1’, doing so by rotating the adjustment using the arrowed tab. It has a detent you can feel. Set this at anything other than ‘1’ and your exposures will be shot in the worst way – overexposed – unless you really are using a filter. With the adjustments available in LRc who needs a filter?

The Lunasix Pro F is not only a competent daylight meter. It can also measure flash, and I recommend reading the manual about how to do that. The speedy response of the silicon blue cell permits this function and the meter can measure either reflected or incident light. Try that with your fancy DSLR! I have tested the meter in my flash equipped studio and can confirm it’s accurate.

An alternative: Recognizing that not everyone needed flash measurement, Gossen released the Lunasix Pro SBC. It’s far easier to find on eBay than the F model and except for the deletion of the flash measurement capability is identical, using the same Silicon Blue Cell and a 9 volt battery. It uses the same wonderful ’null’ method of metering and includes the incident light sphere. The operating manual can be found here. Excellent examples can be found for under $50.

Adding indexes to LTM lenses

Film, Leica, Lenses

Tricky.

For an index of all Leica-related articles click here.

Having added two Canon Leica Thread Mount lenses to my little Leica M3 outfit, I found it difficult to easily align the lenses properly when fitting them to the M3. There’s a small red index line on the LTM-to-M bayonet adapter but it’s very hard to see when the adapter is mounted on the lens.

What I was missing was the red index hemisphere (“dome”) found on all Leitz M mount lenses, like on my 90mm Tele-Elmarit. These are absent from LTM lenses from any manufacturer:



The indexing dome on the 90mm Tele-Elmarit

In addition to providing visual indexing when mounting the lens, these domes also provide ready tactile guidance so that you can literally change lenses in the dark almost as easily as in daylight.

A couple of minutes on eBay and I was hosed down $10.23 for two minuscule red plastic indexing domes, arguably the costliest plastic per ounce on Planet Earth. Still, watcha gonna do? (I searched for “Red Dot Marks for Leica Lenses”). Be sure to clean your lens’s mounting surfaces with some isopropyl alcohol before proceeding.

The domes measure 3.2mm in diameter (0.1255″), identical to those used on Leitz rangefinder M-mount lenses.



The domes with the 35mm and 50mm Canon optics.
Miniature tweezers are essential for easy placement.
Red circles indicate correct locations.

As you can see these are very small and you must use a pair of miniature tweezers to place them in position. The red circles indicate the installation points.

While some use cyanoacrylate glue I find it’s far too runny and impermanent for this purpose. Those domes are going to get knocked about in use and CA glue just does not cut it. What is needed is two-part epoxy and there’s none finer than regular JB Weld. Avoid the quick setting version (weaker), go for the real thing:



One rivet for mixing, the other for application.

Next it’s time to mask the rear rings on the lenses to avoid unnecessary and ugly over-application of the mixed epoxy:



Scotch tape masks. The adapter has been removed
from the 35mm as it overlaps the rear lens mount.
This makes for better Scotch tape adhesion.

You have two choices. Apply the epoxy to the dome (high risk of dropping the dome as you hold it in the tweezers) or apply the epoxy to the lens (far lower risk, and the Scotch tape mask further mitigates error). After applying the smallest amount of epoxy to each lens, the domes are placed in position using the tweezers followed by light finger pressure for a good seal. This is why you want to use as little epoxy as possible. Squeeze out is ugly. Maybe lay off the coffee before these steps?



The domes in place.

Yes, the dome on the 35mm lens overlaps the far f/22 depth of field index but I’m not about to use that optic at f/22 where diffraction ruins resolution. So it’s a non-functional issue.

JB Weld two part epoxy takes 24 hours to fully cure at 70F. Not 20, not 16 not anything lower. Put the lenses aside and come back a day later. You can hit the coffee now.

Keks M-meter for Leica M

Cameras, Film, Leica

Finally!

For an index of all Leica-related articles click here.



Finally!

If you like to use an exposure meter for light readings and use a film Leica M1, M2, M3, M4, M4-P, M4-2, MA, MD, MDa or MD2, you will be ordering one of these unless you are lucky enough to have a functioning Leicameter M/MC/MR/MR-4.

Finally someone has crafted an accessory shoe meter for the film Leica M which couples with the shutter speed dial.

By way of background I suggest you read my comprehensive piece on the Leicameter first.

Then if accessory shoe mounted meters are of interest read this. I have been using that minuscule Reflx meter with success but I would be the first to admit that speed is not its forte. As with all other accessory shoe meters it is not coupled to the Leica’s shutter speed dial. Decide to change shutter speed or aperture and you must first dial in the new shutter speed/aperture on the meter (slow), then take your light reading (fast) and transfer the indicated aperture/shutter speed to the lens (even slower). It takes time. And you have to struggle with that too small shutter speed dial on the Leica with its even smaller shutter speed engravings. This gets to be less fun and more challenging as anno domini kicks in.

By contrast the coupling Leicameter models attach to the shutter speed dial so you set your shutter speed using the knob on the meter (fast), take your light reading and transfer the aperture to the lens. That knob is large and easy to handle and the Leicameter’s engraved shutter speeds and apertures are large. Pretty speedy if you work in shutter priority mode.

Well, Keks has updated the Leicameter with a 1.3 inch OLED display while retaining the shutter speed dial coupling feature. With the Leicameter MR/MR-4 the angle of measurement is equivalent to that of a 90mm lens, which is 26 degrees diagonally. Thus you can use the 90mm frame selector lever for ‘aimed’ exposure measurement. The pidgin English on Keks’s site states: “30 average metering (Approximately 50mm Lens view)” which is wrong as 30 degrees is closer to the field of view of a 90mm lens. If it is 30 degrees that’s a good thing. (The diagonal angle of view of a 50mm lens is 46 degrees).

The battery, while rechargeable (ugh!) is said to deliver a 10 hour life after a one hour USB-C charge. Assuming that the display is set to stay on for 30 seconds – the period is adjustable – once a reading is taken that translates to 1200 ‘on’ cycles or 1200 exposures – call it 33 rolls of film. For me, with a 50% ‘keeper’ rate, that’s a long time and a lot of film. And Keks claims the battery is user replaceable, and while I see no hatch for the replacement, this is promising. See below for an image of the base retaining screws.

Eventually all batteries, rechargeable or not, die. Ask owners who laid down $7,000 for their Leica M240 digital not so long ago for which no replacement batteries are available. That’s a costly paperweight and Leica should be damned for no longer making the batteries. (The market is too small for Chinese aftermarket manufacturers). With the Keks M-meter, maybe you have to undo four screws in 5 years’ time? And they claim it uses a common rechargeable cell. It’s unclear from their images whether the four retainers for the base of the Keks meter are rivets or screws. Hopefully the latter, if their claim about the battery being replaceable is true.

This is not Keks’s first foray into light meter manufacture. B&H lists a couple of models in a variety of finishes, so there’s some reason to think Keks know what it is doing. Here are the specifications for the Keks M-Meter from their site:



Keks M-meter specifications.
That ‘Max/Min aperture’ customization setting is interesting.

Using images from Keks’s web site, here is my forensic analysis with thoughts and questions:



Keks’s meter is less wide (70mm) than the Leicameter MC and MR/MR-4 at 71mm.
At 17.3mm front to back it’s 2.7mm slimmer than the Leicameter.

That’s good news. It means more clearance for an aftermarket rapid rewind crank which I consider an essential enhancement to the stock M knob rewind. While the paper specifications suggest a 1mm width difference it’s clearly more like 5mm, looking at the above and top plate images.

It looks great:



On a Leica M2.

The display is big and clear. Lets hope Keks programs a black-on-white option:



The buttons on the right are for ISO setting.
If you use EVs those are also displayed.

You recharge it using USB-C:



Recharging. The rear button is for taking a light reading.
One press for instantaneous reading, two for continuous.

And you don’t even have to remove it from the camera. And there’s no funky specialized 1.35 volt battery considerations like with the Leicameter MR/MR-4. Looking at the images on the Keks site it’s clear that the socket at the meter end is USB-C, not the awful and fragile Micro-USB. Good:



USB-C recharging socket on the meter.

And here’s a surprise:



British (design) and Best.

It looks like the retainer, lower right, is a hex head Allen screw, but it’s hard to tell. Here’s another image – the same goes for the accessory shoe retainers. I have increased the contrast in their image to make things clearer:



Hex head Allen screw retainers?

The coupling pin for the Leica’s shutter speed dial is there – let’s hope they got the length and location right:



Coupling pin.

The various Leicameters had five screws in the accessory shoe – three to attach it to the meter and two to tilt the meter left to right to ensure proper coupling of the pin with the camera’s shutter speed dial. The Keks appears to have the three attachment screws only, no provision for tilt, but I imagine one could easily shim the shoe in the event of incomplete pin coupling with the shutter speed dial. It looks like they are using Allen head hex screws (hard to tell from their images), so this has to be determined in practical use.

And it looks like exposure compensation is a feature:



Exposure compensation setting.

If this meter functions well, Keks will sell a lot of these. And I will be one of their first sales. With a functioning Leicameter MR-4 selling for $200 and up, and they are all end-of-life, this is a bargain. Keks offers variants in black chrome or shiny black paint for those thus inclined. The black paint version is on brass for fetishists who like the worn/war zone look. The other two are on an alloy base.



My order.

The final icing on the Keks cake? If your early M3 has the 1/5, 1/10, 1/25, 1/50 etc. shutter speed progression you can set it up so. How cool is that? And you can limit the aperture and shutter speed ranges displayed to your specific hardware. For example, the aperture range in the Keks goes down to f/128 whereas the smallest aperture on any Leica lens that I am aware of is f/32. And you can switch between full stop, half stop and one third stop intervals. The same applies for ISO settings. Shutter stops are at full values only. Display brightness is adjustable in four steps (25%/50%/75%/100%) and Auto. The display ‘live’ time is adjustable from 30 seconds all the way to 5 minutes in seven steps. Hard to see using anything other than 30 seconds. A 15 seconds lower limit would be better. You can calibrate the shutter speed to correctly match that set on the camera in case it’s off. Nice.

The only drawback I can think of, compared with the MR/MR-4 Leicameter, is that you have to turn the Keks on to change shutter speeds. Not a big deal as you will be taking a light reading before doing that in any case.

You can download the user manual by clicking here. It’s silent as to battery replacement.

Canon 35mm f/2 LTM

Film, Leica, Lenses

Small and highly regarded.

For an index of all Leica-related articles click here.

I wrote at length about the Canon 50mm f/1.4 Leica Thread Mount lens here. I was so impressed with the build quality and finish of the 50mm lens that I added the 35mm version to my Leica M3 outfit. Stylistically the design of the 35mm f/2 is identical, though the aperture ring and the focus distances have been switched to black backgrounds:



Identical ergonomics to the 50mm f/1.4 lens

The lens sports the same gorgeous, black, scalloped focus collar as the 50mm, a non-rotating focus mount, equally spaced apertures with whole click stops and a non-rotating focus cam at the back. Strangely, the infinity lock of the 50mm optic is missing from the 35mm lens which is very compact and weighs in at just 139 grams with a protective filter and bayonet adapter in place. This makes it a tad harder to mount or remove on the Leica though there is substantial knurling on the mounting ring to help with grip. (The 50mm has no knurling as with the infinity lock no additional grip is needed). I am mystified why Canon deleted the infinity lock from this lens.

Whereas the 50mm lens has a 180 degree focus throw from 1 meter to infinity, that on the 35mm optic is far shorter, just 90 degrees for a like range. This lens is better suited to the M2, M4, M5 and M6 with their included 35mm frame lines in the viewfinder. My Leica M3 has 50/90/135mm frame lines but rather than use a shoe-mounted auxiliary finder I use decades of memory about just how a 35mm lens captures images and can largely make do with the 50mm finder plus some imagination. The big benefit of the Canon over the Leitz 35mm Summaron, of course, is the absence of those clunky ‘goggles’ which rather take away from the ‘small camera, small lens’ concept of the Leica. That and it’s 1.5 stops faster.



The Canon, with bayonet adapter, alongside the 35mm Summaron RF

As is clear from the above image my version of the Canon is in beyond mint condition. After some 5 decades it looks as if it was just removed from its original box, and the functions are as good as the appearance. The optics are crystal clear and the diaphragm looks new. It’s as if the lens had been stored away all those years and never used, with pristine white and orange paint filling the engravings. Comparing the optical designs you can see that the Canon’s is a bit more complex than the Summaron’s, having added a 7th element to the simpler symmetrical Gauss design of the Leitz lens. Hardly surprising as the lens was computed a decade later.



The design of the 35mm f/2 LTM Canon.



The Leitz Summaron for comparison.

Purchasing considerations are identical to those I set forth in the earlier piece on the 50mm Canon. That means you will likely be buying from Japan, where there are dozens available on eBay, and most will have fungus (excuse me, “pinpoint fungus, does not affect image” as listing after listing would have it), haze or scratches. Many show the white lettering faded to a disgusting yellow and while the engravings can be cleaned and refilled there are probably better things to do with your time. As you can see mine has none of these issues but I had to screen many examples before finally paying $385 with tax and shipping for my mint copy. That’s a fraction of what even an f/2.8 Summaron costs (half a stop faster than my f/3.5, reckon on $1200) and if you start looking at f/2 Summicrons or f/1.4 Summiluxes well, there goes a couple of months’ rent money. Mine came from Japan and took a scant 4 days to arrive, just as with the 50mm, for a reasonable shipping cost of $35.

Canon actually had two different optical designs for this lens. The first had serial numbers from 10041 through 36967, made 4/62 to 12/70. The second was 37237 to 45064, 1/71 to 3/75. Mine is the second design and is reputed to be marginally improved in the corners wide open. An earlier f/1.8 version is reputed to be softer.

I had to add an LTM-to-Leica-bayonet adapter from Fotodiox for $16. This time I chose one which would bring up the 135mm frame in the M3’s finder to remind me that I have the 35mm mounted; that same adapter will bring up the 35mm frame, correctly, on an M2 and subsequent rangefinder body. Thus, should I receive a severe blow to the head and spring for a digital Leica M body down the road, I will save all of $16 on yet another adapter. An $8 multicoated UV filter in the strange size of 40mm (not the more common 40.5mm) completes the ensemble, for a total outlay of $409. Yes, Amazon carries the odd sized filter. As with the 50mm optic, the red lens mounting index on the adapter is very hard to see and I will be adding a big red plastic blob, epoxied in the appropriate location on the rear of the lens barrel.

I checked focus accuracy at infinity – perfect – and at 1 meter using a laser measure, where the rangefinder was just 0.3″ out. Not a material error. That’s the second under $20 Fotodiox adapter I have installed and both are well nigh perfect. Save your money and don’t spend more on used Leica or other brands purporting to be better. Cameraquest is asking $79 for the allegedly superior Rayqual. Well, there is one born every minute, I suppose.

Here is the Canon on the Leica M3. Can you spell ‘gorgeous’?



On the M3, with a slimline 40mm UV filter fitted.

Finally, here’s how the lens balances on the camera.



Balance on the M3.

Early results appear here.

A detailed resolution test appears here.

Sharpening the 35mm f/3.5 Summaron RF

Film, Leica, Lenses, Lightroom

Pretty easy.

For an index of all Leica-related articles click here.

The other day I was pixel peeping, at 100% magnification, images from the Leitz 35mm f/3.5 Summaron RF taken on Kodak Ektar 100 film. These would make 48″ x 72″ prints. Two things are obvious. There is minor red fringing chromatic aberration, easily removed with one click in the LRc Develop module. And while this image, taken at the lens’s sweet spot of f/8 will easily make a 13″ x 19″ print, start cropping and the definition is not quite there. Given that this is the least expensive Leitz branded 35mm lens you can buy (other than the poor earlier 35mm f/3.5 Elmar in LTM) and realizing it was first sold some 70 years ago, I’m not grumbling. But can we get a quart out of this pint pot?



1/250th, f/8, Kodak Ektar 100, Noritsu HQ scan.

Reading up on various sharpening applications I came across one named Gigapixel from Topaz labs, a long time maker of LR plug-ins. They offer 20 full trial attempts and place no watermark on the enhanced image. Nice. The cost is $100. The examples on their web site are startling, showing massive improvement in micro-contrast and detail. Using the above image I could not remotely get comparable improvement. Indeed, if there was any improvement I was very hard pressed to see it. Either Topaz Labs is using an especially ‘friendly’ image which supports their technology or this is pure snake oil. Either way, $100 saved.

Next I took a look at Affinity Photo 2, v.2.6.0, using their Develop Persona and Document->Resize Document, quadrupling the displayed pixel count, for a file which accordingly grew to four times the size:



The Document dialog in Affinity Photo 2.

Again, I could barely notice any difference compared with the original. Pass. Lots of disc space saved.

Next I tried LRc’s native controls. In the Develop module I went to Photo->Enhance where, for JPGs like this, there is only one active option named Super Resolution:



Super Resolution in LRc.

Well, the file size again quadrupled but the difference was again negligible.

Hmmm, none of this works.

Then I recalled that LRc has a simple Sharpen slider in the Develop module, one which I had not looked at in years as I was using good lenses with large digital sensors, no sharpening needed.



Optimal sharpen settings.

Now I really started seeing improvements. In the Develop module you can see ‘Before’ and ‘After’ images by hitting the ‘Y’ key, and here they are, at 100% magnification. Again, that translates to a 48″ x 72″ print:



100% pixel peeping, ‘Before’ (left) and ‘After’.
Click the image for a large original.

Look at the detail in the flag and in the fluting of the Grecian columns. A very significant improvement. Now I am not about to make prints that large but now I know I can crop images from this ancient optic and get great prints from the crops. Not half bad for an ancient bit of bottle!