Fast wide angle lens to use with GH1

joe1946 said:
So I guess my 55mm wide angle from my Pentax 67 will still be a 55mm wide angle on my GH2 , r i g h t.
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Even better example is my small digicam that has a focal length of 6.5mm at the wide end. Following this logic it should therefore have an ultrawide "look". Intead it has the same FOV and near/far relationship as a 35mm lens on a 35mm still camera. It has plenty of DOF however.
 
AFAIK, DOF means "Depth Of Field". So, it there is "plenty of DOF", it should mean that Depth of Field is large (so the answer is: deep). :)
 
Late said:
Not true.

http://dpanswers.com/content/tech_crop.php#per
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Let me clarify my statement here. What I meant to say was position the camera (not the foreground object) so that it's the same size. No matter what camera you're on (if you're comparing the two lenses on the same camera) a 20mm will always make the background appear further away than the 50mm. I can see how my statement was confusing because I said that it distorts space the same way as a fullframe camera, what I meant to say (was writing this very late) was that it distorts space the same on a fullframe camera relative to another lens on the same camera. Wide is a relative term.
 
ZeusFaber said:
I like all the explanations about FOV etc... But in layman's term I think the two photos above says everything.
Is there someone who sees some differencies?
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http://en.wikipedia.org/wiki/Perspective_distortion_(photography)

Look down on examples, the second example.

This is basically saying the same thing as the article, but shows that if you're comparing lenses on the SAME camera, and moving your camera, not the object, space distorts differently. Lens to lens on the same camera.
 
To get a decent FOV for indoor shooting, 14mm is the longest focal length one should consider.

Panny should release mechanical M43 primes for the GH1/2/3.
 
Still waiting to be corrected by the estimable LPowell.


shaveblog said:
LPowell, I have too much respect for your accomplishments to argue with you. Also you're much smarter than I am, so there's that, too.

If I'm missing something here, what is it? Am I perhaps not phrasing things accurately? I once got sucked into a similar argument with a pedant whose sole objection to my position regarding 2x crop factor as it relates to FOV was that it's impossible for a lens to literally physically change into a longer focal length, which of course no one has ever claimed but it does make for a nice straw man.

My eyes tell me that a 20mm lens on an m43 camera behaves more like a 40mm lens on a traditional 35mm camera than a 20mm lens on that film camera does. The math behind the 2x crop factor seems to support what my eyes see, and even the manufacturers themselves have agreed, across the board, to describe, say, a 20mm lens designed for m43 as a "40mm equivalent" or "40mm effective". All of this fits together nicely, and is repeatable when I mount a 50mm lens on my GF1 and the resulting image looks like that of a 100mm lens on a 35mm film camera.

But still there are some like you who dismiss the above and maintain that a 20mm lens always behaves like a 20mm lens no matter what the crop factor is. That merely cropping the image to the center portion of the lens doesn't result in the effective doubling of FOV. I have to admit that most who fall in this camp don't impress me with their arguments, which seem a sort of catch-all grumpiness about the digital erosion of photography in general. But you're not one of these folks, and I take what you say very seriously.

What's getting lost in translation here? I'm all ears. Thank you.
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I'll answer you:

Full frame 35mm, or Vistavision, is (roughly) twice the size of 4/3, which is the same (roughly) as 35mm academy motion film. So we can talk of doubles and halves freely, or else it's too complex.

A 50mm lens is a 50mm lens. Period.

On a full frame 35mm the 50mm lens will produce a normal field of view (or angle of view if you prefer) similar to that of a 25mm lens on a 4/3 camera. OK, easy we all get that now.

However, it is known that there are 4 things that affect depth of field:

1. Size of capturing sensor
2. Focal length of lens
3. Size of aperture
4. Distance at which lens is focused.

As far as I am aware, that's it. It's this first one we're changing. So the 25mm lens on the 4/3 camera will have much deeper focus at all apertures, and all focal distances than the 50mm lens on the full frame, despite the identical angle of view.

Now, LPowell is saying (I believe) that the 50mm lens used on a full frame will be cropped down on a 4/3 camera due to it's projection falling onto a smaller sensor, which will give the result of a tighter field of view, BUT the depth of field characteristics in the remaining portion of the image will be EXACTLY the same as they were on the full frame camera. Hence the notion that "a 50mm lens is a 50mm lens. Period"

In a very real sense, he is absolutely right.
 
of course,, its a f**k load easier to say a 20mm M43 lens gives a view like an old 40mm lens on the old camera's :) most people understand it that way.
 
Theres also teh Tokina 11-16mm f/2.8 for Nikon mount with the aperture adaptor. For that bower I would just go with the panny 15mm f/2.5
 
You're probably right... But I was thinking about full manual lenses, if the Panasonic 14mm f2.5 focus ring is anything like the 14-140 ring (focus by wire) it's a pain to use a FF with.

One can say you wouldn't need FF on 14mm, but you never know what are you going to need when making a film.
 
im looking to pick up the panny 7-14 mm. not the fastest lens out there but il be shooting solely mountainscapes with it. so light should be aplenty. i need that SUPER wide hehe
 
He is right. The end.
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Lol, well until the next episode

But I was thinking about full manual lenses, if the Panasonic 14mm f2.5 focus ring is anything like the 14-140 ring (focus by wire) it's a pain to use a FF with
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If you wanted a mechanical 14mm prime, there is also the Samyang 14mm 2.8, which is available in various mounts.
 
I just don't get why you would want to have follow focus on a super-wide.

If you look at the last range of Contax Zeiss rangefinder glass, the G series, which is really the best series they have ever made for stills 35mm, titanium bodied, rear element super close to the film frame etc. you find several interesting things. First is the 45mm f2 which is by some MTF tests I've read, (and by my own eyes when I owned one), the sharpest lens ever made (well, in the top 3 certainly) at any focal length. Then you look at the Super-wides - the 8mm and 16mm. they are fixed aperture f8. Literally, that's it! Why? Well, both for mechanical reasons, but also because when you're shooting that ultra-wide, you want sharp full depth of field images almost always if not always always. Shooting ultra-wide, depth of field is still very very deep anyway, even at f2.8, so focus pulling is a nonsense. If you already have 20ft of softish but in focus dof at f2.8, it pretty much always makes sense to make it 10000000ft of super sharp dof at f8, unless you want to do very barrel-distorted near-focus, focus-pulling tom-foolery, which is just a cranky reason to spend $$$$ on a wide lens.

I think that Panasonic have got it right with the 7mm-14mm at f4. I'd shoot it at f8 and hyper-focal distance every time I could.

On the other hand I would love for the 14-140 mark 2 to be f2.8 throughout the range though, even if the compromise was making it more like 14-85mm. It's sharp and good, but just too slow. 14-85mm f2.8 would be fine for everything I shoot. (Equivalent to 28mm-170mm fov) - A huge range, super practical, more creative zoom lens already! But that's for another thread...
 
Thanks for the responses, everyone. I am sincerely grateful to those who took the time to respond, especially Lucas. Thank you.

I guess in the end it's a matter of semantics. From my perspective as someone peering through an adapted Canon lens on my GF1, a 50mm lens offers a view comparable to a 100mm lens on a 35mm film camera. But I understand how field of view isn't the whole story for some, even as it pretty much is for the 98% rest of us.

Again, gentlemen, thank you.
 
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