Why are rangefinder lenses better?

[snaggs]

Yes, Ive read its because the rear element can be closer to the film plane. Why is this better? Wouldn't this make pre-TTL lens designs better than those which need 15mm in front of the film plane (i.e. Hologon vs Biogon?)

Daniel.

 

[RML]

Are they better?

I think things have more to do with design, machining, manufacturing and QC than that RF lenses are inherently better than other lenses.

 

[Huck Finn]

You've opened up a huge question with this one, Snaggs. And it would be an even more interesting question on a forum with a lot of SLR users - say Nikon or Canon. 🙄 It's especially interesting given the fact that many modern wide angle RF lenses use retrofocus designs to improve correction of spherical aberrations.

IMO, RF lenses show advantages over SLR lenses in many cases at or close to maximum apertures but not when stopped down. I would guess that RF manufacturers have maximized optical performance at these apertures in response to consumer demand because many RF users like to shoot in low light without flash. In contrast, this is not an issue for most SLR users who are more likely to be shooting with flash & therefore are not as likely to be shooting at maximum aperture.

My 2 cents . . .

 

[RubenBlaedel]

I have the almost rangfinder hasselblad swcm with a biogon 38 mm 4,5 and it is not retrofocused as there is no mirror it has to pass.
I have compared this to the 40 mm and 50 mm wides for hasselblad and the 65 mm for my fuji gx 680 - the fuji lens was so badly retrofucused with barrel like results that I sold it, the to hasselblad lenses were ok but not near as distortion free as the biogon.
The 35 mm summicron is far better lens then any glass i put on my slr canon eos camera including L series.
I do not know what RF lenses that are retro focussed but I would out of my own limited experience say that RF glas except for macro and tele - works and feels better for me.
I have a 120 mm s-planar (early c , non T* coated ) macro lens that is not optimized for infinity but for close up and a sonnar 250 mm (early c , non T* coated ) that is sharpest wide open - both lenses produce beatifull Bokeh - wicth I can not say about other zeiss lenses for Hasselblad. I have renamed Bokeh to SOFA - A sofa should be soft and comfortable and Soft Off-Focus Areas or Silky Off Focus Areas gives more meaning to me than Bokeh 🙂

 

[Pherdinand]

OK, dunno if they are REALLY better even wide-open...but do a simple idea:
Compare ANY manufacturer's 50mm f/1.4 SLR lens to leitz, voigtlander, zeiss, canon, etc corresponding fast RF normals. Normal lenses are said to be the easiest and cheapest to manufacture that's why i take them as example.
Then look at the prices.
You can do the comparison with less extreme speed, say f/2 - although not many SLR lenses are made today as 50mm f/2. They are considered too slow. But let's take a manual focus older type 50/2 lens, any of the existing ones. Well, same thing again: in RF world they are much more expensive unless you go for the FSU. I don't think the quality difference between, e.g. a Minolta Rokkor 50 mm f/2 SLR and a Sonnar or Voigtlander corresponding RF lens is really that big, both are well built, both are sharp and produce pleasant pics.

But you can go wide or ultrawide too. 28/2 SLR lenses are plenty and considered very good. 24mm and 20mm f/2.8 lenses are also quite common and well respected, although getting more expensive. Still far from the wide/ultrawide prices in the RF category.

You can also go towards longer focals. Take any top 80-85mm fast (f/1.4) lenses like canon L, minolta G category. They are expensive but also very good. Take then the Leitz corresponding and open a savings account.

I am not saying that RF lenses cannot be better than SDLR ones but honestly i don't think the large price gap is based on their superior quality.
Fact is, there are much more SLR lenses sold so their price can be much lower.
Quality control...i don';t think that's an issue unless you go the cheapest way and then, it's the same problem with RF lenses.

Finally...it's not only the lens that influences the end result. RF's can be focused more accurate in some cases, can be handheld easier etcetera. All contribute to the degree of sharpness.

My apologies to all the rf enthousiasts (like myself). 😀

 

[Pherdinand]

Ruben, i like that SOFA thing🙂 may i use it without paying you a fee?

 

[RubenBlaedel]

YES please do spread the word - I would love to see the Bokeh word replaced with SOFA. Would it not be great to be able to say - "...besides that this lens has a beatifull SOFA" - even the wifes would pay attention to what we say for once 🙂
-or even better start a new thread on the matter - my modisty prevails me from doing it my self! :angel:

 

[Pherdinand]

YES please do spread the word [...] -or even better start a new thread on the matter - my modisty prevails me from doing it my self! :angel:

Done🙂 with poll🙂

 

[berci]

I like the SOFA.
To tell the truth it's just a random posting, because my post count was 66 and i had to increase it.

 

[giellaleafapmu]

Yes, Ive read its because the rear element can be closer to the film plane. Why is this better? Wouldn't this make pre-TTL lens designs better than those which need 15mm in front of the film plane (i.e. Hologon vs Biogon?)

Daniel.

I guess this might be true for some wideangle design. For ultrafast lenses it might be true the opposite,
at least if the designer wants to keep the front element to an acceptable size (even thought in the field of low light photography rangefinders have other things to offer, like precision in focissing and possibility of shotting at slow speed hand held). In facts, many respectable people rate the Summilux R better than the M version (here I have to belive what others say because I could not afford any of them).

Giella lea Fapmu

 

[RML]

Where is the poll?!

 

[Nikon Bob]

For my use and limited experience level I can see very little difference between photos taken with my rangefinder lenses or my Nikkor lenses. RF lenses tend to be smaller and lighter than the equivilant focal length/speed lens in the Nikkor line. I can tell you which is more expensive secondhand, Leica. Either will take a very nice photo if I'm up to it (most times not), so I would say that RF lenses are not vastly superior for the average user. The RF system (camera body and lens together) is a better choice for handholding at lower shutterspeeds if focal lengths under 135mm are all you need.

Bob

 

[Huck Finn]

I do not know what RF lenses that are retro focussed

It is wide angle lenses where non-retrofocus designs matter. The 21/2.8 Elmarit, replacing the legendary Super Angulon, was the first retrofocus wide angle RF design from Leica. Most Zeiss wide angle designs, like the Biogons & Hologons, are non-retrofocus, but the Distagon, which will be used for the new Zeiss 15/2.8, is a retrofocus design. Typically the non-retrofocus designs, including the many Leica double Gauss variations, are symmetrical and the retrofocus designs are typically asymmetrical. Many of the CV designs are non-retrofocus. asymmetrical designs. In this case, they use the available space in the rear to introduce retrofocus element to correct for aberrations, an easier & therefeore more economical approach to lens design. However, it can also result in physically larger lenses like the 28 Ultron, which lose the rangefinder advantage of compact size.

 

[Pherdinand]

Where is the poll?!

HERE IS THE POLL.

 

[RubenBlaedel]

Pherdinand - it looks like SOFA is going into oblivion - it was to good to be true so cyberspace killed the initiative to once for all get rid of Bokeh - alas a secret poll sound like the oposiitons candidates on an election list in Bella Russ or Zimbabwe 🙂

 

[Roger Hicks]

Beyond about 50mm to 58mm there's no reason why they should be: you can use the same design and still clear the flipping mirror.

Below about 50mm you have to have quite a lot of retrofocus in an SLR lens to clear the mirror, and a good rule of thumb is more retrofocus = lower quality (more distortion, lower contrast, more aberrations).

Sure, you can get around this if money is no object, and you can gain a few advantages as well: better telecentricity, for a kick-off.

I think this is one of those things that used to be more true than it is now, but there's still a good bit more than a grain of truth in it. And some non-reverse-tele designs, such as the Biogon 38/4.5 (which I have on an Alpa on 66x44mm format) have never been bettered.

Cheers,

Roger (www.rogerandfrances.com)

 

[RubenBlaedel]

66 x 44 mm ??? is that on special roll film or ?? is it the same Biogon 38 mm 4,5 that is on my swcm - not the same but -- same size/costruction etc ?

 

[ddutchison]

While I'm not really convinced that RF lenses are inherently any sharper than SLR lenses, I am convinced that a hand-held RF camera will produce sharper images than a hand-held SLR due to the fact that there's no mirror flapping around in the body at the moment the shutter is fired.

That's why I like RF's. A camera on your shoulder, and two or three of those tiny lenses in your pockets is the pretty close to functional equivalent of an SLR, Camera bag, and tripod.

 

[Beniliam]

In my IMHO the best thing of the RF cameras is the relative compact size of the lens. But I dont think that the quality of Leica lens VS other companies is better. Because the size of thee negative is always the same, using Zuiko lens or Zeiss lens. Probably you can register more detail in the negative, but this detail make that the lens were more expensive...

The majority of the lens are better than our photos...

 

[Roger Hicks]

Dear Ruben,

Masked down 6x7cm (from Alpa). The Biogon has only an 80mm circle of coverage; yes, it's the same lens as on the SWC/M but on a format I much prefer and in a camera that most people find easier to hold steady. They are however very rare lenses: only about 100 in Alpa mount, in 2 series of 50, and little or no likelihood of a 3rd series.

And I completely agree with Beniliam that most lenses are better than most photographers.

Cheers,

Roger