Fuji X mount lens announcements (June 2012)

[Shashin]

Noise is a product of the sensor size, though.

In what way?

Shashin, you were the one who said, "But they do have an f/0.95 equivalent. And who has a 35mm equivalent at f/0.95?"

You are reading either more into what I said or not getting what I said. Very simple statement: for an equivalent 35mm FoV, m4/3 has an f/0.95 speed lens. That is it.

Maybe I'm wrong, but your statement implied that m4/3 having a f.95 lens is some kind of advantage over a larger format that doesn't have such a lens. The simple point that we're trying to make is that there isn't usable advantage to the .95 lens on a m4/3 camera over an f1.9 lens on a 35mm camera if the end result is the same.

Not comparing formats. Just saying that for a certain FoV, this is the fastest lens out there. And there is one big benefit, it is two stops faster, which, if you really care about noise, lets you use ISOs two stops slower for a particular shutter speed under a particular luminance level.

I don't compare everything to 35mm. I use several formats, and, I'd imagine, like most photographers, I plan things in terms of field of view, DOF and the ability to enlarge (i.e. noise,) both of which are sliding scales amongst different formats, and both of which have general equivalents as the sensor sizes change.

Really? That sounds very complicated. I usually just take my best camera and control it to get the results I need.

A 6mm lens is still a 6mm lens on an iPhone and a 6x6 camera, and an f1.2 lens is still an f1.2 lens on an aps-c camera and a 35mm camera, but the results vary depending on the format, and it makes sense to understand that sliding scale as you move from format to format. It doesn't really matter to me what the lens says, as Paratom mentioned, but, rather, the final output. I think that's all we're trying to get at.

Right, so your choose the right format for what you need and you forget about equivalency when you use it. Actually, I find the focal length is important because it lets me know my FoV and the aperture lets me know how fast I can shoot. Most photographers I know feel the same way.

For my pretty innocuous post, it certainly has become very a complicated conversation.

 

[retow]

In what way?

Not comparing formats. Just saying that for a certain FoV, this is the fastest lens out there. And there is one big benefit, it is two stops faster, which, if you really care about noise, lets you use ISOs two stops slower for a particular shutter speed under a particular luminance level.

F 0.95 tells only part of the story. It's a specialty lens. Heavy, bulky and with an optical performance which is not among the best of breed. F 1.4 is the sweet spot where lenses can still be reasonably compact and have good peformance fully open.

 

[Paratom]

But the numbers on the lens are related to DOF/FOV, but not noise, which is not a product of the optics. The point which I think you missed was it is rather pointless to buy a format in the hopes that it works like a different format. Not only is it impossible, but it would take to much effect to do all the equivalency calculations. For example, if you need the fastest shutter speed from the system, then I would open the lens to the maximum aperture. If DoF is important, stop down. When you want to balance those two thing, find out the smallest aperture that will give you the shutter speed you need. All that can be done without reference to a different format and every photographer that I know does this.

Sashin,
I dont see I missed anything. It might be pointless for you but for me it is usefull to compare to 35mm/ff because that is what I know best. Specially because I have shot a lot of primes I understand what to expect. I dont like to buy something and the find out what would be the best I can get. I first like to have an understanding of what I need and then buy the equipment. There enough other factors which can not be judged upfront (specially regarding user interface). I dont calculate all the time when I shoot, but it helps me to get a better undertsanding what to expect. Thats also the reason why I do like to us primes very often, or when I use zooms I often first select the focal length and then zoom with my feet (when possible). After some time I usually get a good understanding for each lens. I know that f2.8-4.0 works good for shallow DOF portrait on my S2, and I also know that I like using the 45/1.8 near wide open when I want to seperate a portrait from the background with the OMD. I know I can generate some shallow DOG with the kit lens of the Nex, but I cant generate shallow DOF when I use the kit lens of the OMD. So I know which system can achieve which results for me and based on that I select.
By the way if you like shooting that 17/.95 wide open a lot I recommend buying a ND filter for bright days-thats at least my experience when I use the 50/.95.

 

[douglasf13]

In what way?
Not comparing formats. Just saying that for a certain FoV, this is the fastest lens out there. And there is one big benefit, it is two stops faster, which, if you really care about noise, lets you use ISOs two stops slower for a particular shutter speed under a particular luminance level.

Paratom pretty much answered all of this more eloquently than I could, but I wanted to highlight the above quote, since it is the crux of the whole thing. Yes, if you have a lens that is two stops faster, you can use an ISO two stops lower...however, the point is, the larger sensor's ISO is about 2 stops cleaner, so there is still no advantage.

Of course, this depends on sensor technology, but assuming that you're using relatively recent cameras in the comparison, it more or less holds true. Sometimes the smaller sensor is a little cleaner, sometimes the larger one is, depending on the cameras being compared, but it largely holds true these days.