GH2 THE ULTIMATE FAST WIDE SHARP and CHEAP LENS FOR GH2 !!!!!!!!

S

seb33

Well-known member
AT LEAST I've found the PERFECT WIDE SHARP and CHEAP lens for the GH2 !!! It's a C-mount Pentax/Cosmicar 6mm 1:1.2 lens I've bought 9.99€ (12.50$) on Ebay !
The rear barrel had to be modified for 20€ (watch pictures below) to fit on the C-mount to micro 4/3 adapter (Kipon).
This 6mm focal lenght on the GH2 gives a huge vignetting on micro 4/3 sensor, but thanks to the new crop 1:1 GH2 function, the vignetting is disappearing completely !
This 6mm lens with the crop function gives nearly the same frame (same width but less height) than on the Lumix 14mm 1:2.5, but much much more faster.
It's a sharp lens, even with the crop. In 24X36 eq. it's a 30mm.
This lens is incredible for GH2, there is no other competition for such a fast lens !

In this movie you will watch daylight tests (always @ 1:1.2, 1/50 shutter speed, 160 asa) with a 22€ Polaroid 43mm variable ND filter and a 40.5 to 43mm step-up ring, there's my girlfriend preparing her new collection for children "Pitchoovintage".
Then you will watch night test, from 160 to 3200 asa, always @ 1:1.2 and 1/50 shutter speed.

GH2 24P
Crop mode 1:1
No CC
from 160 to 3200 asa
from 1/25 to 1/50 shutter speed
C-mount Pentax/Cosmicar 6mm 1:1.2
edited on Adobe Premiere CS5

music : Elusive "Intro" + "writing on the wall" from "Pressure Drop" EP
duration : 4mn49sec
 
Just goes to show that you can get nice "cinematic" images with a 2/3" format camera, pretty much what you get at the 2x crop on 4/3.
 
the rear barrel has been limed to fit and go enough deeply in the C-mount adapter for infinity focus
 
Don't get me wrong, I love the spirit of experimentation and the willingness to try new ideas. And the whole idea of adapting an old c-mount lens to my m43 camera is way too cool. Even the cheap CCTV c-mounts look bitching, never mind the collapsible rangefinder lenses.

The problem I have with all the c-mount m43 videos I see online including this one is that the end result just doesn't look as good as I wish it did. It's a low contrast, softish look, and frankly I can already get that with the full-size MF glass I already have, especially my $25 Vivitar 28mm f/2.8 Close Focus, without futzing with funky little CCTV lenses and paying someone to grind down an adapter ring.

Tip of the hat to seb33, though, very cool proof of concept.
 
shaveblog said:
Don't get me wrong, I love the spirit of experimentation and the willingness to try new ideas. And the whole idea of adapting an old c-mount lens to my m43 camera is way too cool. Even the cheap CCTV c-mounts look bitching, never mind the collapsible rangefinder lenses.

The problem I have with all the c-mount m43 videos I see online including this one is that the end result just doesn't look as good as I wish it did. It's a low contrast, softish look, and frankly I can already get that with the full-size MF glass I already have, especially my $25 Vivitar 28mm f/2.8 Close Focus, without futzing with funky little CCTV lenses and paying someone to grind down an adapter ring.

Tip of the hat to seb33, though, very cool proof of concept.
Click to expand...

Well it's been a while I'm experimenting C-mount lenses. This one is a little softish, but don't forget we are here in the crop mode. And this is the first time I have a "wide" and fast lens, there is no other option on micro 4/3, due to its 2X crop sensor. I've test the Olympus 9-18mm zoom, it's sharper but it's 1:4 minimum aperture. With the Pentax, this is for me the first time having an equivalence to the Lumix 14mm 2.5, but faster.
 
I want a wide/fast m43 lens too, but I want it without having to use ETC, which apparently comes with its own issues according to some who've tested it (I haven't as of yet).

I just don't think a true wide/fast lens is in the cards for m43, given the 2x crop. And I'm mostly okay with that. I like normal 40-50mm lenses best, and short teles around 70-80mm. A fast wide would be nice to have as an option, but it's never a lens I feel a pressing need for.

Now, the new 25mm f/1.4 native m43 lens Panasonic says will be available this summer? That's a lens to lust for. I love the 20mm f/1.7, but an even faster native "nifty fifty"? Done and done.



seb33 said:
Well it's been a while I'm experimenting C-mount lenses. This one is a little softish, but don't forget we are here in the crop mode. And this is the first time I have a "wide" and fast lens, there is no other option on micro 4/3, due to its 2X crop sensor. I've test the Olympus 9-18mm zoom, it's sharper but it's 1:4 minimum aperture. With the Pentax, this is for me the first time having an equivalence to the Lumix 14mm 2.5, but faster.
Click to expand...
 
I've worked few days with the 20mm 1.7 and the 14mm 2.5, filming rehearsals and lyrics singers, at the end I've noticed that I shoot mostly with the 14mm, its wider was more convenient, and it gave me good results.
 
shaveblog said:
I just don't think a true wide/fast lens is in the cards for m43, given the 2x crop.
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Actually this thinking is backwards. It's easier to design a wide/fast lens for a smaller sensor than it is for a larger sensor. True, nobody's made one yet, but it's not that it can't be done. Look at the Olympus zooms, the 14-35 is twice as fast as any comparable zoom for any full-frame camera.

I've got a 5.9mm f/1.8 lens on my 16mm movie camera, which would be equivalent in field of view to about a 9mm on m43 or 18mm on a "1.0x crop" sensor. I don't think there's any such thing as an 18mm f/1.8 lens for "full frame" out there, is there?

The smaller the sensor, the easier it is to make a faster lens for it. My set of prime lenses for 16mm are all f/1.1 to f/1.25. You don't find those in "full frame" very often, those would be extremely rare and wildly expensive.

Another example -- Red makes an 18-85 lens for the Red One and other PL-mount 35mm cine cameras... It's a foot long, probably 7 inches in diameter, and weighs 10 pounds, and opens to f/2.8. I just picked up a Super16 lens which is 17.5-70 (so almost exactly the same focal length). It opens to f/2.2, it's six inches long, it's two inches in diameter, and it weighs about 20 ounces. Granted, it only covers Super16, which is too small to fully cover the entire GH2 sensor, but it's surprisingly close, and covering a smaller sensor even with the same focal range lets the lens be practically microscopic as compared to the larger-sensor lens, and much faster. And a ton less expensive, this S16 lens is brand new and was literally less than 1/10th the cost of the Red zoom (which, by the way, is incredibly inexpensive for an S35 zoom lens!)

So -- point being -- while nobody's done it yet (a truly-fast, truly-wide lens that compares to the 14mm Canon f/2.8), it's not far off. The 7-14 is just as wide as that Canon, and just one stop slower. They could probably match or exceed the Canon's performance in m43 easily, if they'd just make the lens a little bigger, and if they thought people would pay for it. Keep in mind that the 14mm Canon f/2.8 is $2,359.00. Would an m43 user, buying a $350 GF2 or whatever, really spend $2359 for a single lens (and not even a zoom at that?) The 7-14 is a zoom that costs about a third of what that prime lens costs. Is one stop slower performance really that much of a tradeoff, to get an equally-wide zoom?

Point being, if customers show that there's a demand for it, I have no doubt that it can be done, and actually done easier and less expensively than for the larger-sensor cameras.

Case in point -- the 25mm Voigtlander f/0.95 lens. Same field of view as the Leica Noctilux 50mm f/0.95. Same f-stop. 1/10th the price.
 
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Not sure my thinking is backwards, just the interpretation. The 2x crop doubles effective FOV, which means lens designers need to shoot for 10mm to hit 20mm, 12mm for 24mm, etc. If you're saying that's not an issue, that's good news. But it still seems reasonable to assume that the 2x crop might have something to do with the lack of fast/wide native m43 glass.

I can't think of any other reason why Panasonic and Oly don't seem to be interested in doing fast wides for m43. Both companies "get" the marketing appeal of wide and fast glass. Panasonic proudly trumpets the fast/wide Leica-branded lens on my wife's LX5, so clearly the company gets the broad appeal of "fast" and "wide" when it comes to camera lenses. So why not for m43?

I nor any other straw man ever said it couldn't be done. Obviously it's possible to do a wide, fast (<f2) native m43 lens. That nobody's done one yet, though, even for gobs of money, begs the question why not? Why did Panasonic come out with a wider pancake for m43 but significantly slow it down (14mm f2.5) after the 20mm f1.7 has been such a widely-praised hit? The pancake isn't a must-have because of the focal length, but because it's fast enough to shoot indoors in practical light. That's a godsend to me, and I imagine most m43 shooters. It makes the pancake my default lens, the one I keep on my camera most of the time. When the new 25mm f1.4 comes out, if its IQ is as good as the 20mm's it will undoubtedly replace it as my leave-on lens. There is no way Pana/Oly don't understand this concept.

I'd love to see a fast wide m43 lens happen, and I'll buy one when it arrives if it's priced similarly to the pancakes. If it's so easy to make such a lens, it shouldn't be terribly expensive, right?
 
The pancake is nothing to do with performance, it's all about size. Look at the size of the Voigtlander 25mm lens, and compare that to the size of the Lumix 20mm. A faster lens has to be bigger. The pancakes are not interested in ultimate speed, they're interested in ultimate tiny size.

The Voigtlander costs $1,000 for a single-focal-length lens. I would dare say that in the Panasonic and Olympus marketing meetings where they considered new lenses, it never crossed any of their minds that someone would pay $1,000 for a single-focal-length lens for a tiny GH2 or G10 or GF1 or Olympus PEN or whatever all these cameras are. Voigtlander took a wild stab in the dark, and appears to have hit a home run. I can only hope that their success will get the other manufacturers to re-evaluate the feasibility of other types of lenses.

It is obviously possible to make a fast/wide lens, I'd go so far as to speculate that it can easily be done, but the lens will be bigger and more expensive. The whole point of m43 is smaller and cheaper. That's its marketing niche against the traditional DSLR. Smaller, thinner, cheaper. That's why the pancakes are such big hits -- smaller, thinner, and 1/3 the price of the Voigtlander.

and I'll buy one when it arrives if it's priced similarly to the pancakes.
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Case in point. A fast/wide for the Canon costs $2400, but you want one for m43 to cost $300. Therein lies the problem, and why nobody has made such a lens yet.

If it's so easy to make such a lens, it shouldn't be terribly expensive, right?
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Why do you think those two things are related? I would think that it would be (compared to all other lenses of similar type) terribly expensive, just like a fast/wide on a full frame camera is "terribly expensive" compared to normal focal lengths. What I'm saying is that it could certainly be done, it's not some big massive engineering feat, and it could probably be done easier for m43 than it could for full-frame. And maybe it would even cost less than the FF equivalent. But that doesn't mean it would be cheap, especially when you consider that it would likely be a much smaller target market. Sure, Cosina's selling every Voigtlander 25mm lens they can make, but -- how many is that, really, as compared to the 20mm? If I were to make a wild guess, I'd bet that there's a hundred 20mm pancakes being sold for every Voigtlander. And therefore, the Voigtlander costs $1,000, and the pancake costs $330. How many Nikon bodies are out there, as compared to m43 bodies? Probably 20 to 1 (considering Nikon's been out for decades) so there are probably a minimum of 20x as many customers who would be able to consider a fast/wide for a Nikon, as opposed to those who would consider it for m43. Bigger market = more economy of scale.

If the demand is there, someday someone will make the fast/wide you're asking about. And it will probably cost about as much as an equivalent fast/wide for other cameras, maybe a little less. Which would put it at about $1500-$2000. And now I have to ask -- would any reasonable mass-market customer buy a big, bulky, fat, $1500 lens for their pocket GF1? I think we all know the answer to that. And hence, that's why the pancake came out instead. Tiny, small, pocketable, kinda wide, kinda fast, and $320.
 
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