john_griffin1

Several well respected people have physicaly measured the distance between the lens flange and pressure plate as well as been informed of the actual distance from Leica and Hexar. The difference is .05mm in this measurement. The difference of .2mm is the difference in two dimensions called the same thing (back focus) but refering to two seperate actual measurements; flange to pressure plate in the Hexar and flange to film surface or focus plane in the Leica. The only disscusion must be is an error of .05mm important? When you add film bulge, RF accuracy/calibration and manufacturing tollerance into the debate then it's not so clear cut.

Hexar backfocus 'error' is .2mm i.e 3x what I observed and

corrected on the Rokkor!

Thinking of getting one to partner my 40mm Rokkor on my M6. It seems

compact and should allow selective framing without producing

obvious 'tele photo' imagery. Just as My 40 is wide without being

obviously so. I would welcome opinions from owners. I thought long

and hard about a 90mm but with the .72 finder the frames are just

too small.

Just got my latest test film back after I DIY adjusted the back

focus on my 40mm Rokkor ( see previous posts). Looking at

them with my 15 x loupe on the lightbox they are a vast

improvement on the first test ( .07mm is a significant error!) -

sharp as a razor!. Only the very corners are slightly soft but

nothing that's obvious. Shots into the sun show no trace of flare.

I'm one happy guy with this tiny £200 wonder! ( when I get my

LS4000 back from Nikon service I will post some resolution

examples)

At a recent Leica open day the resident tech discovered that my

1000th was realy 500th on my M6! I was pretty sure it's been allright

before as I've used this speed quite a lot with tranny - however a

recent test film confirmed the worst. I watched as he tested the rest

of the speeds and they were all quite consistent - only out by 10-15%

( very good for a mech shutter!)

How can 1 speed be way off and the others OK and can it be fixed? -

preferably DIY.

The 50 has the most natural perspective when compared with

our own eyes but the world looks more natural through a .72

mag finder with the 35mm frame - depends how you take

pictures - do you see a picture independent of your camera and

then put it to your eye to capture it or do you look for the picture

through the viewfinder?

Mark,

Based on the Leica specs of a flange to inner rail distance of

27.75mm - placing a spacer on the inner rails of 0.05mm puts

the ground glass at the same plane as the film surface and the

plane at which ( give or take the errors induced by film bulge)

leica lenses are designed to focus which is 27.8mm. Using the

inner or outer rails as the register should produce a

misalignment with the RF. It's a common mistake to think that

the inner rails are in the same plane as the film surface. I found

some archival film sleeve which was exactly .05mm ( not .5mm)

as measured by my micrometer - works accuratley for me and I

can't see any reason why a GG screen in exactly the same place

as he film plane can be anything other than bang on accurate as

long as you use a powefull enough loupe ( 15x is what I use)

and use a very contrasty subject.

Andrew,

I have some test film in the camera at the moment - I 'll post

some tests as soon as I get it scanned etc.

After my initial disappointment with this lens (see previous posts) I

compared the RF focus with a ground glass screen at the film plane

(inner rails + 0.05mm spacer)to make sure it was aligned properly. I

found that the back focus was too long as the RF and ground glass did

not align at any distance. The rear helical which connects to the RF

cam on the body was spot on at all the distances and even though this

is adjustable in the lens it wouldn't get rid of the error (and yes

the RF mech on the body is spot on).When I dismantled the lens to

give it a regrease I found a spacer ring on the second helical that

sets the back focus and by gradualy grinding this down by 0.07mm) I

was able to bring the RF and film plane focus into alignment. So it's

got a second chance - which is nice because I really like it's small

size, it's accuracy in the 35mm frame and the quick focus from the

tab!

If the flange to film distance is greater on a Hexar than on a Leica (and there is plenty of evidence that it is) then you will never get it to focus properly at infinity (although by adjusting the cam you can get it to work at shorter distances). Although depth of field will mask small errors as you stop down - the critical depth of focus is very small on an ultra wide for critical work it will make a difference.

Unfortunatley on close examination of some high res scans of the

negs - it's a lemon! Fuzzy in the red end of the spectrum and no

where near as sharp as my 50 cron. My fave test is to switch between

the red green and blue channels at different areas of the neg on a

2700+dpi scan in Photoshop - with my 50mm summicron there is no

shift between channels and there is no fringing around the

highlights. With this lens you can see the image shift around

slightly and there is colour fringing on the highlights. Before you

blame the scanner - if examine areas of dust scratches these stay in

the same position through the channels and the image can be seen to

shift in relation to them.

Ah well - you don't get something for nothing I guess!

Picked one up today based on the many positive comments from owners I

got from my previous post. £199 from Classic Camera in London - which

seemed very fair. A quick look at a neg film test reveals sharp

definition wide open across the whole neg with only a bit of

softening in the very far corners.It also focuses accuratley from

infinity to under 1m (so the cam rate is a leica match) The threads

are a bit dry so there's a bit of play so my first job is going to be

a re-grease with Nyogel. The glass is flawless amd there are no signs

of use on the barrel. I can't believe how small it is - 23mm from the

flange at infinity - together with the tab it makes my M6 a very

compact and quick tool. I checked the 35mm frame lines with the

coverage on the neg and at infinity there is still a tiny bit to

spare on the neg. All in all I reckon I've done quite well - pre-

aspheric F2 35mm summicrons are up for 3 times this amount in the

same shop!

They are easily the cheapest in the UK as far as I have seen - I have bought from them in the past and their service is very good.

I'm toying with the idea of getting one in place of a 35mm lens - the

difference is very small by my calculations (6deg HFOV) and as the

framelines on my M6 seem very conservative the 35 frame could well be

bang on at all but close up? (a bit of filing needed on the mount to

make it bring up the 35 lines). The lens looks small and compact,

which is nice, and a tab for quick focusing and a F2 are further

attractions -as well as the low prices I have seen. Anyone use one of

these and how are they opticaly compared to a pre aspheric 35/2

summicron? sharpness, flare resistance and Bokeh?

Karl - never heard a good thing about Leica UK service.

Well done on doing your own repair - it's not rocket science! - as long as you understand what you are doing and have the right tools there should be no problem. With in-warranty equipment I always get the manufacturer to sort it out - as you would if you had new car. However I run an older ( way out of warranty) car and would'nt dream of sending it to a main dealer to have repairs and maintenance done at extortionate rates.

Keep getting a server error when I want to sign up with my home E-

mail address. There seems to be less new postings than on the

greenspun BB - who else is having problems - oh yeah, dumb question, -

if you cant get on you can't answer!

In 5 years time pictures taken with the latest digital cameras will

look primative compared to the new designs - you are stuck with

the original capture file. In the same time span there will be a

similar improvement in scanner and manipulation

software/hardware - the info is still on the film and can be

improved on.

There is a critical focus issue with this lens ( all wide lenses on

an RF camera IMO) - observe the actual amount of travel from

infinity to close up ( it's tiny!) - if the flange to film distance is even

a fraction out on your camera - see a previous thread on this

issue then you can get large focusing errors by trying to use the

lens scale. There is a large depth of field but it's the depth of

focus that is small and for best results a film test wide open on

focusing distances around infinity is advisable. Generaly I have

made the following observations on this lens ; a slight softness

at the corners but nothing obvious - this is a very sharp lens!.

Don't stop down beyond F8 as it gets soft all over due to

diffraction - F5.6 is best. There is vignetting ( a function of the

laws of physics rather than poor lens design)- slide film may be

a bit of a compromise in exposure in contrasty situations. There

is some compression of tone and loss of contrast in the middle

of the frame - but this is nitpicking when you look at the price/

performance equation! - if you need a 15mm you can't go wrong

but I find it far too wide -it screams 'WIDE ANGLE' at you!

Oh and watch where you put your fingers if you don't want them

in the frame.

"My guess is that you won't even know who those people are" - you

guessed wrong - Glinn and Hass belong to the very fine and long

tradition of documentary photography - Eggleston plays a different

game in a different ball park - not better(or worse)just different.

If Hass and Glinn did indeed refer to Egglestones work in such terms

it reflects a very narrow view of the photographic world on their

part.

"And he's boring, boring, boring. " - most good works of creative

endevour will to a large extent reflect the sensitivities and

perceptions of the veiwer.

IMO he's freed himself of the conventions and traditions of

photography - it's cliches and formulas of composition and subject

matter - to produce a totaly unique body of work.

He is, in his own words, "at war with the obvious" - and he's

winning !

I have just got a reply back from Solms and they are going to try to

get Leica UK to supply the pressure plate - nice!

The flange, as you have both pointed out, is more problematic. There

is a high spot at 5 O'clock where the brass is showing through -I

reckon a lens has been pulled up somehow (dropped or hit)as this part

of the flange is unsupported by a screw into the body and is easy to

distort. The flange itself is machined on the back face ( the only

place where the brass is bare) to give the correct flange to film

rail distance (27.95mm to outer rails) - assuming there is no damage

to the internal body It should be possible to give the thickness of

the flange ( via my micrometer) and get one as a replacement this

way? I know the 'right' thing to do is to get it to a tech but I

bought it cheap and with my DIY adjustments it now aligns with

infinity (stars) and at 1,3,5 and 10 m distances when I do a carefull

fine grain film test. I guess however it could be right on axis but

have a slight tilt.....?

Somehow the film pressure plate was bent on my M6 - and also the lens mounting flange! It's properly had a hard life in the hands of a previous owner I guess. I have bent the plate and the ring back to nearly true (RF and focusing checks out on carefull test film images now) but I would still like to replace them. I have just tried to order some new ones from Leica UK but was refused! - I can understand the reason for the flange as I was told it was machined to fit but the pressure plate just screws on so what's their problem. Anyone else had any success or faliure at ordering parts?

T-max 3200 'IS' a 1600 ISO film IMHO. Get it deved at 3200 but rate

it at 1600. I would'nt bother with trying to push TMY to 1600 if you

need any shadow detail - you won't get any.

You don't get a true 400 when you push - you will lose out detail in

the shadows compared to a true 400 film.

Same thing with my M6 classic and 50 cron - I DIY aligned it with

infinity but it consistently focused too near on every other distance

from 1m upwards - now I have adjusted it back and it's very slightly

off at infinity - I can live with it as any shots at this distance

are going to be stopped down quite a bit - I wouldn't mind it being

spot on though.