HI, I have a M6TTL bought recently brand new, the pictures came out using 35mm, 28mm, 50mm lenses look great and sharp, but when I use it with my 90mmAPO lens, the print came out some how soft and not 100% focused, even the rangefinder is line up on the subject, but the picture is still not sharp, I try many times already, I don't know why, is it becasue of the 90mm lens got some problem? Please help, Thanks!!

-- Mitchell Li (mitchli@pacbell.net), April 23, 2002

Answers

Several factors could contribute to the soft appearance of your 90mm shots, Mitchell, including: bad lens, misaligned rangefinder, poor focus (user error), and camera shake. I'd suggest doing some testing by putting the camera on a sturdy tripod and shoot something that creates a continuous line going away from the lens, such as a picket fence. Label the point you're focusing on in some manner (a yellow PostIt note?), and then see how the focus matches to what you intended. On the same roll, from the same position, take a couple of hand-held shoots for comparison, as well. That should give you some answers. Or, more questions, depending on how your luck is going. ;-)

-- Ralph Barker (rbarker@pacbell.net), April 24, 2002.

Mitchell - in addition the Ralph's good suggestions:

1) What magnification finder do you have? The .58x is more likely to show focus problems with a telephoto, and the .85x is less likely, on average. A .72 should work with a 90 f/2, except....

2) ... be aware that there can be some variation (within specs) among rangefinders and lenses. If you happen to get a lens and body that are a little off in the same direction, the errors may add up to the point they shwo on film. I now always test a potential body or tele lens with the equipment I already have to make sure a nice 'marriage' is possible.

I have 2 90s and 2 bodies, and each lens "prefers" one of the bodies over the other; I have to use the f/2 on the M4-P and the 2.8 on the M4-2.

So, if possible, try your lens on another body and your body with another lens to see if any pattern develops.

-- Andy Piper (apidens@denver.infi.net), April 24, 2002.

Welcome to the 90SAA Focusing Problem Club. You need at least .85x magnification to get consistently accurate results, and more so required at f/2 to f/4. Get the 1.25X magnifier, which has helped me, but hasn't solved my handling lssues. Miss my Nikkor AF 85mm f/1.4D!

-- Kristian (leicashot@hotmail.com), April 24, 2002.

Or better yet, get a M3 with the .91 mag. DoF is down to nothing so you need all the help you can get...

-- Russell Brooks (russell@ebrooks.org), April 24, 2002.

The M6 I have is .72 ,the shutter speeds I used is 1/60 and 1/125 at F5.6 and F4, so I don't think camera shake is the issue here, I also notice the spot behind the subject I try to focus is always sharp, so must be the bad lens then.

-- Mitchell Li (mitchli@pacbell.net), April 24, 2002.

It happen.

Leica had to replace mine because of that.

-- Lucien (Lucien_vd@yahoo.fr), April 24, 2002.

Just because the 90 is always off in the same direction, don't assume it's all the lens's fault. The camera might be out a little and it wouldn't necessarily show with your 50 and wider lenses.

Remember that any 90 f/2 is the equivalent of a 45mm f/1 Noctilux magnified by a 2x tele-converter - =8^o - so it will show up a camera RF error that is fully invisible even with a 50 at f/2.

Try shooting something a mile away at infinity with the 90. See if the RF images line up right, and then see if the picture is also sharp.

Even an M3 isn't a guarantee - I put a 90 APO on an M3 in a shop the other day and the RF was off by a frames width at infinity. Without trying other lenses there was no way to know which was actually off - the lens or the camera.

-- Andy Piper (apidens@denver.infi.net), April 24, 2002.

Sorry, I was not clear.

It was impossible to have a sharp picture with my first Apo-Asph. Even on a bench. A scratched Thambar was much better. I think that one of the glasses was not at the right place.

It was replaced without any discussion by Leica.

The new one is still one of the sharpest lens I ever had.

I look forward to buy the future Apo-Summicron-R Asph. f/2/90 mm for my R8.

-- Lucien (Lucien_vd@yahoo.fr), April 24, 2002.