Tag Archives: clean

Cleaning E. Leitz Wetzlar Summar Haze

Exterior mystery crust

The Leica lens, E. Leitz Wetzlar “Summar” 50mm (5cm) f/2 is notorious for having internal haze, clouding images sometimes giving a desired warmth called “Leica Glow”. Some desire it for using as a portrait lens or other such use as the effect is warranted.

Before I show you how I got my 1939 Leica Summar lens apart to clean the haze, I first cleaned some kind of dried gunk on the front element that resembled very bad cleaning marks.

I had seen it before on my former 1936 Summar and other people complaining about their’s calling it cleaning marks, so it must be a somewhat common thing. This time it was more crusty, uneven looking that led me to believe it wasn’t just the glass itself.

my former 1936 Summar with mystery crust around front element
my former 1936 Summar with mystery crust around front element

 

I looked at it with a loupe and could see it was raised, some kind of crust or crystallization. I scratched at it with my fingernail and sure enough it flaked slightly. Perhaps a buildup of years of cleaning fluid?

summar_gunk-01
here is my 1939 Summar with back light showing the mystery crust

 

I knew conventional cleaning wouldn’t work so I tried the method for removing Fungus on a lens. A 50/50 mix of household Ammonia and Hydrogen Peroxide then rinse with tap water. It immediately started working, almost foaming around the edge where it was thickest.

after cleaning the mystery crust
after cleaning the mystery crust

I had to repeat twice, as is usual, but a nice clean outer lens now with just a few true cleaning marks.

Clean the interior haze

Now I must say, while searching for tutorials and methods of cleaning the haze, it was kind of confusing because it was rarely stated that, in fact, the front name plate is attached to the front ring and the element itself.

It was also stated several times to unscrew the front element right from the lens base and people were having trouble because it would just unscrew the front group. I came up with a way to easily remove the front element.

 

First unscrew the front lens group from the base, just above the aperture ring.¬†Extent the lens tube fully so it won’t spin in the base and grasp the outer knurled ring and turn it counter-clockwise ‘ccw’ it should unscrew fairly easy.

hold the outer knurled ring in one hand and the base in the other (with lens tube fully extended) and turn ccw (counter-clockwise)
hold the outer knurled ring in one hand and the base in the other (with lens tube fully extended) and turn ccw (counter-clockwise)

 

Unscrew fully and remove from lens base.

after removing the front lens group. Mine could use some new black paint around the edge of the element (red arrow)
after removing the front lens group. Mine could use some new black paint around the edge of the element (red arrow)

 

NOW is the time to unscrew the set screw ‘ccw’ in the nameplate (red arrow) so it will separate from the front lens group. It’s tiny don’t loose it.

remove the set screw (red arrow)
remove the set screw (red arrow)

 

Now you need some kind of grip tool to aid in holding the front group housing while removing the front element. I used an electrical cable, about the same diameter as a pencil or slightly smaller but not too small.

‘Fire Wire’ cable I used as by grip tool. any cable with a rubbery shell will work.

 

not clear here but, the front lens group housing extends backwards with a nice metal tube to grab onto with your tool just behind the front element ring. Firmly grip your tool around the group housing and firmly grip the front ring and unscrew ‘ccw’.

make a loop and wrap it around the rear of the front lens group, behind the front element ring
make a loop and wrap it around the rear of the front lens group behind the front element ring

 

The entire front knurled ring, nameplate and front element are attached together. Mine came right off, I’ve read it could be difficult and a good soaking of the front element in isopropyl alcohol might help.

front element removed. now clean backside of front element and both sides of rest of the group front group
front element removed. now clean backside of front element and both sides of rest of the group.

 

Again, I used the 50/50 mix ammonia / hydrogen peroxide to clean the haze from all inner elements except the lens behind the aperture blades as I didn’t want to risk damaging the aperture unit/blades.

here is the aperture blade unit ij the lens tube. I cleaned this lens behind it with isop. alcohol
here is the aperture blade unit in the lens tube. I cleaned this lens behind it with isop. alcohol

 

Blow out any dust and fuzzies from cleaning before reassembly. I found what looked like dust in mine that turned out to be bubbles in the lens glass. I’ve read this is normal. ¬†Here’s a before and after the cleaning shot.

before and after. big difference
before and after. big difference.

 

It looks great mounted on my 1953 Leica IIIf. It does have a few cleaning marks and some mishandled scratches in the middle but it was cheap and it’s mine.

Summar mounted on my Leica IIIf
Summar mounted on my Leica IIIf