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neilsphoto
03-03-2005, 14:38
I know, I know I have alot of questions for someone who hasn't even gotten an R-D1 yet but I am ondering what with all the glowing reports and lovers of this camera has nobody had focus problems wide open and close up?

I've read of focus being ahead and behind the subject, of Canadian Summicrons being apparently a poor match to the camera, of people going through multiple bodies only to give up etc...........

So of this group who has had problems and with what lenses? If I had an R-D1 I'd use mostly a 35 ashp 'lux (would behave like a 50 asph lux), a 50 summicron ( a 75mm 'cron on an RD) and I'd try for sure my 75 'lux. How well are these working. Wish I hadn't sold the 24 but I did.

Thanks

Neil

BTW those "tiny" in my first impression RD RAW files dowloaded made a sweet 8x12 print.

krimple
03-03-2005, 14:47
I have had trouble focusing quickly enough with a 50 f/1.5 sometimes, and maybe even accurately. But usually when I have time to set up the shot, even wide open, the RF focuses well enough. Don't forget also that wide open with most lenses the image quality is quite soft to begin with, which some interpret as bad focus.

I also shoot with a 15, 28 and 35mm lens, and the margin for error decreases proportionately the wider I shoot. I would be afraid to mount anything > 75mm or so on the R-D1 for anything but a static shot.

Ken

neilsphoto
03-03-2005, 15:09
But it is static shots in close at or near wide open that I've read aren't sharp. A 35 asph lens is sharp side open, can't blame that lens for soft focus. My 50 'cron wide open is also very very good. If it's good on film on an M camera it ought to be good on an R-D1 right?
I was asking about missed focus where repeatedly the focus is wrong even on a tripod and a fixed subject. Reports of this are out there yet seldom here. So I'm just wondering as I know I'd be doing close tight portraits in low or available light with an R-D1 just as I do on film now.

Ed Schwartzreic
03-03-2005, 16:22
After having my rangefinder adjusted perfectly by DAG, there are 2 lenses I wanted to use which do not couple correctly, although they do so on my M's: one is my Canadian 35/1.4 and the other is a 75/1.4 which Leica Germany had brought up to specs a few years ago. I have posted about this before; DAG stated to me about this in an email: "even Leica Cameras have a problem with cams lining up. Some lens cams couple to the top of following arm, some more in the middle & others couple to the lower part of the cam, if the cam is slightly tilted then there's a problem. If one keeps looking into the possible areas of problems like this one can easily wonder how a camera can work correctly."

The other M lenses I use regularly all couple well.

Ed

krimple
03-03-2005, 16:30
Maybe for those users... It could be that their rangefinder is slightly out of alignment, or that they have a wider aperture and therefore the rangefinder can't focus accurately enough for that lens. My f/1.9 Ultron 35mm lens and f/1.5 Nokton 50mm lens generally focus well enough. I don't own a Summilux or anyhing < f/1.5.

Ken

krimple
03-03-2005, 16:37
As an example--with the 50mm f/1.5 Nokton focused wide open at 1/11th of a second handheld. I focused on the nose:

http://www.pbase.com/krimple/image/39950138.jpg

And another example -- I think this was the 50 and I'm pretty sure it was close to f/1.9...

http://www.pbase.com/krimple/image/37551038.jpg

jlw
03-03-2005, 18:02
I'm attaching test pictures with three of my own lenses, so you can form your own opinion!

These were made via the 'ruler test,' which is a very sensitive measure of focusing-system accuracy. You mount a ruler at about a 45-degree angle to the camera, at a close distance (1 meter in this case) then focus very carefully on the center point (in the case of my ruler, the 6-inch or 36-pica mark.) You make a test picture at full aperture, then look at the ruler markings in the image to see how the actual range of best focus compares to the intended focus point.

Depressing fact you'll learn: If you perform this test several times in succession, each time removing and defocusing the lens before replacing it, you'll get slightly different results each time! There are a lot of factors being tested besides rangefinder accuracy, one of them being the acuity of your own eye!

Quick verbal summary of my results: the 35/1.7 Ultron seemed to be focusing accurately, although its relatively wide DOF gives it a lot of margin for error. My 50/1.4 Canon seems to be focusing slightly in front of the intended plane, although keep in mind that because the ruler is at an angle, the actual amount of "miss" is only about 1/2 inch. And the 85/1.5 Canon seems very nearly bang-on accurate -- hmmm, not what I had expected, but nice!

Note that the files are of different pixel sizes because I cropped them to show only the center part of the ruler; with different focal lengths, naturally, this results in files with different pixel dimensions.

Here are the pix:

krimple
03-03-2005, 18:11
jlw,

I see what you're saying here. And that's with a full tripod setup, etc. Maybe the short baseline of the rangefinder is causing the lack of accuracy in focusing with that level of accuracy. f/1.5 is as far low as I go. The f/1.9 Ultron I have rarely has a focus plane issue. The f/1.5 Nokton has it sometimes, but not usually. I really haven't had too many throw away images from that lens though (unless you count the ones with too slow shutter speed, etc..)

We went through the same round of issues with the Canon DSLR and the EF lens set at first, as digital shows all the imperfections that a 4x6 image print at a photo lab won't. Canon had a headache adjusting all those lens and body combinations. Maybe I'm just lucky (or not discriminating enough).

jlw
03-03-2005, 18:18
Another caveat about the ruler test: Very few lenses have a perfectly flat plane of best focus. In other words, if you were to focus very, very exactly with the subject perfectly centered, then pan the camera slightly from side to side, you might find that the plane of best focus would now be slightly in front of or behind the original spot. The ruler test is accurate enough to detect these small variations. So, if you put the RF spot on the center mark, focus carefully, then move the camera to reframe the picture, your focus may move even if the rangefinder is "perfectly" accurate.

In other words, there are lots of causes for small variations that usually keep any camera (yes, even ones whose names begin with "L") from being 100% accurate on the ruler test, even though it can produce perfectly good-looking pictures in the real world.

In other words, it's a useful test, but you don't want to sweat it too much. Normally, as long as my intended focus mark is about as sharp as the sharpest focus mark, I figure the rangefinder is doing its job and don't worry about it.

On the other hand, if various lenses are consistently off by several inches in the same direction, I suspect the RF setting or camera mechanics. If various lenses are off by different amounts in different directions, I suspect the lenses.

andrewch
03-03-2005, 22:24
I rountinely use my Noctilux at f1 indoor, and I have extremely high hit rate with it. Theoretically this shouldn't happen considering the short base length of the camera. But in practical use, I find that it can give very predictable result as long as you are careful with focusing. I am attaching 2 pictures that are both taken with the noctilux at f1, the one of my dog was taken very close to 1m.

Jim Watts
03-04-2005, 03:31
It was me that posted the examples of the front focusing problem with the Canadian 35mm f/2 Summicrons wide open. These examples were handheld as I was at my friends at the time and did not want to bother with a tripod (and it does create a typical 'real world' situation). I have carried ot a more controlled test on a tripod with the same results. These are the only lenses that I have tried that I have personally found a problem with.

My Wetzlar 50mm f/2 Summicron is fine wide open and close-up with accurate repeatable focus. My 90mm f/2.8 Tele-Elmarit (the lens that should suffer most from the short rangefinder base) wide open is the same. I am current borrowing a friends VC 40mm f/1.4 Nokton and have Ruler/Newspaper tested this wide open at 0.8 meters and although the depth of field is incredibably narrow used like this, again if one has the time to focus it carefully, it is accurate and repeatable.

In general I don't think I am seeing more error in my focusing (as distinct the forward focus issue, which like Ed I put down to the lens cam's), other than caused by myself, due to the shorter rangefinder base than with my M4. The 1.0x viewing against 0.72x helps compensate for the shorter base I think. If you are wide open, working close and fast with a non static subject you are always going to get a high number of misses. At least it at zero film cost with an R-D1. ;)

I asked Epson U.K. about the front focus (and hot pixel) problems at 'Focus on Imaging' earlier this week, they seem totally unaware of any problems despite the posts on this and other forums including one I made on their own forum. I tried to speak to their engineer who they referred me to, but in the end it was going to take too much time to find an opening. I just hope they took on board my comments that they should visit this forum to get an overview of the likes and problems with the R-D1.

Ed Schwartzreic
03-04-2005, 04:02
Tom Abrahamsson will be going to Japan next week and will be meeting with the engineers at Cosina, who of course make the R-D1's rangefinder. He is acutely aware of the focus problem and will definitely bring it to their attention, along with the photos which DAG took of the innards of the RF mechanism. How exactly this will filter down to Epson though is not clear. Stay tuned.

Ed