Leica: Good News from PMA

[leicapages]

To add to this focusing issue, some DMR users have told me that focusing requires much more precision than with film. Somehow this sounds strange, but it seems true. As a result, the average "hit" rate is quite lower than corresponding use with film. If confirmed, then this IS a major issue for a digital SLR. Hence why a digital R10 would require focus confirmation to be a serious contender in the market.

[topoxforddoc]

With the R9/DMR, focussing was a major problem esp with longer lenses eg 280/2.8 or at the 200 end of my 80-200/4. However, I bought a Brightscreen 1.75x viewfinder magnifier recently having read Guy's posts and it's made a big difference.

Charlie

[leicapages]

I heard it is also quite an issue with lenses like the Vario 21-35mm f/3.5-4.0 (an ideal lens to use with the crop factor). Probably also with the primes wide-open.

[telyt]

Originally Posted by leicar7

Does anyone know if there is an engineering imperative that the quality of the viewfinder image deteriorate with electronic focussing aids?

Any electronic focussing aid requires a significant percentage of light be diverted from the viewing system to the contrast sensor. Result is a dimmer viewfinder unless the mfgr also reduces magnification or reduces the 'bite' of the viewscreen or both. Either of these changes results in poorer manual focussing.

BTW I've mentioned this before but in case some missed it, Canon's white paper on the effective use of AF systems specifically states that with large apertures and close distances (i.e., very shallow DOF) that not only is manual focus more accurate but also that the focus-lock-recompose technique will more than likely cause focus errors. In other words what they're saying is that AF works best where there's enough DOF to mask the AF system's errors. This has been my experience as well: I find that I get the best results focussing manually, as-composed. Focussing as-composed means being able to focus accurately ANYWHERE on the screen, not just at the mfgr's pre-defined focus points. I didn't spend a ridiculous amount of money on high-performance lenses to be content with 'pretty good' focus that appears to be accurate a few stops down from maximum aperture. I want to be able to use my lens' full performace at maximum aperture, that's what Leica lenses are famous for.

[hamey]

Originally Posted by ruiespanhol

People,

Stop the war M and R please!!
I like R camera much more than M but I like M too because I´m one Leica lover.
It was not the system who counts both have great cameras ,both have good points and bad points but the more important bouth are LEICA!!
So if we like to see one Leica brand so much strong they nead to support both systems.

Best,

Rui

Hello RuI.

Like you I love both my Leica R's and the M7, and I have always stated that Leica R and Leica M complement each other.
The R's I mostly use because I have many Lenses, and fits my style of photography, only yesterday I bought the 100mm APO ELMARIT 2.8
For general photography, I prefer Leica R.
But for low light, nothing beats the Leica M.
I find the M7 cumbersome compared to my Leica R but still IMHO I cannot praise the M7 enough as it has given me some fantastic low light shots, wish it was available 20 years ago.
I got my first Leica at the age of 22, I am now 58 and still buying the stuff, so you can still see my faith in the brand.

Ken.

[leicar7]

Doug,

What is a "significant" amount of light needing diversion to the contrast sensor? The SL/SL2 diverted 30% to the metering cell underneath the mirror.

[fotografz]

[quote=leicar7]How much of the R8/9 focussing is a function of the low mag factor, 0.75x, compared to the SL/SL2 with 0.86? My guess would be that it is measurable, maybe even significant. So one tradeoff would be to penalize eyeglass wearers with being able to see less of the frame edges in return for better focussing probabilities. The first time I looked through an R8, I was stunned at the apparent smallness of the image, even from the R4-7, which has 0.80x.

I suspect that's it ... along with a better screen.

When I purchased that magnifier and larger microprism that someone here suggested, I found that I didn't need the screen as much as needed the magnifier on the R9. It has definately increased the hit ratio of in focus images using the DMR.

[telyt]

Originally Posted by leicar7

What is a "significant" amount of light needing diversion to the contrast sensor? The SL/SL2 diverted 30% to the metering cell underneath the mirror.

The SL/SL2 diverted light only at the central metering spot. The rest of the mirror reflects 100% of the incoming light to the viewscreen.

[leicar7]

Doug,

True enough, although the light is diverted to a rectanglar secondary mirror, the dimensions of which I don't know, within which is the 7mm area that the meter reads. The 30% diverted into that rectangular area may be a nontrivial amount of the whole thing. If I remember my SL/SL2 days correctly, that secondary mirror was a pretty good chunk of the big mirror's dimensions.

But, anyway, does anyone know how much of the incoming light is diverted to FV/AV sensors in other cameras?

[telyt]

Originally Posted by leicar7

If I remember my SL/SL2 days correctly, that secondary mirror was a pretty good chunk of the big mirror's dimensions.

It looks like the secondary mirror is about 20% of the area of the main mirror.

[ruiespanhol]

Originally Posted by hamey

Hello RuI.

Like you I love both my Leica R's and the M7, and I have always stated that Leica R and Leica M complement each other.
The R's I mostly use because I have many Lenses, and fits my style of photography, only yesterday I bought the 100mm APO ELMARIT 2.8
For general photography, I prefer Leica R.
But for low light, nothing beats the Leica M.
I find the M7 cumbersome compared to my Leica R but still IMHO I cannot praise the M7 enough as it has given me some fantastic low light shots, wish it was available 20 years ago.
I got my first Leica at the age of 22, I am now 58 and still buying the stuff, so you can still see my faith in the brand.

Ken.

Thanks Ken

[leicar7]

Doug,

Whereas the R8/9 has a secondary mirror that is almost as large as the primary. The SL/SL2 are only losing about 6% of incoming light. It looks as if getting the same brightness to the eye in the R8/9 might be an interesting challenge, aggravated by the problem that when the viewfinder mag factor increases (gets better), the brightness dims.

It would still be interesting to see what would happen if the engineering of the SL/SL2 pentaprism and focussing screen were duplicated in a new camera.

Brighter and bigger is better with FF focussing capability, IMHO.

[zapp]

Originally Posted by visiondr

Gerry,

Here's the item I think was referred to (from DP review)

Since it was presented last year, I really dislike the idea that Leica placed two marks for chosing focal length on the viewfinder. Focal length does not change just because I change the sensor size (i.e digiatl to analog). This is simply unprofessional. Many companies still play the 35 mm equivalent game and are also dead wrong talking about focal length multiplication factors. You can read a lot of BS especially at the german Sony web site talking about Zeiss lenses (go there it is wonderful wordsmithing), Olympus is completely off (relating 4/3 to other digital and to 35 mm film, they even claim funny magnification factor magic for their macro lenses) and Leica is in line with all this at least for the viewfinder as well as typicl replies from Leica reps. What comptetence should I expect from Leica (my preferred company) in the future if they try talking me into focal length multipliers and things llike that? Photography is not limited or a function of 35 mm cameras. Nobody will ever tell you that a 80 mm lens on a medium format cameras is actually a 50 mm lens in some other system.