Luminous Landscape Forum
Equipment & Techniques => Mirrorless Cameras => Topic started by: Bob Rockefeller on September 08, 2015, 07:18:47 am
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It seems as if it's a rare lens indeed in the m4/3 lineup that is faster than f1.8. None of the M.Zuiko line is. Is there something that just makes it real hard to get to f1.4?
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Sensor is smaller than full frame which means that the f stop is smaller.
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Sensor is smaller than full frame which means that the f stop is smaller.
I don't think that's accurate.
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Lens size. To make faster lenses, they would need to make larger lenses, which is in contrast to one of the goals of the system, small size. So it is a balancing act. If they get more demand from people for the faster lenses, they will probably make them, but right now the demand is in smaller sizes.
That said, do you need the speed difference of f1.4 vs f1.8, or would you just prefer optically better f1.8 lenses?
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My guess is that it is a policy decision to keep the size of the lenses commensurate with the sizes of the cameras.
You can get native lenses in f/0.95 (the Voigtlanders, for example). They are manual focus but invaluable for certain applications.
You can also use adapted lenses - m4/3 is about the most flexible for taking other mount glass. Using focal reducers like the speed boosters can net you very fast glass indeed by using eg a full frame f/1.4 lens on a typical speed booster becomes an f/1 lens on m4/3, and an f/2.8 24-70 zoom becomes something like a 35-100 f/2 equivalent.
But if you've used such a combination you'll know they are bulky, heavy and unwieldy (which can cause problems with mount electronics, rigidity in the lens mount resulting in focus asymmetries and all manner of nasties- I wouldn't want to use my speedbooster off a tripod, really).
So I think that's the reason that the m4/3 manufacturers have concentrated on making physically smaller lenses at the expense of max aperture, rather than slapping an integrated focal reducer on existing fast 35 mm lens designs.
I certainly use m4/3 in the mountains precisely because the whole system- camera, lenses and all- are much smaller and lighter than the APS-C/FF/MF equivalents.
Cheers, Hywel
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Lens size. To make faster lenses, they would need to make larger lenses, which is in contrast to one of the goals of the system, small size. So it is a balancing act. If they get more demand from people for the faster lenses, they will probably make them, but right now the demand is in smaller sizes.
That said, do you need the speed difference of f1.4 vs f1.8, or would you just prefer optically better f1.8 lenses?
Lens size may well be the reason and they would like to keep things small. Faster lenses = larger diameter lenses, all else being equal.
Optical quality, of course, trumps all. But I sure would like to see an M.Zuiko 40mm f1.2!
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A fast lens is still a fast lens. Panasonic makes a 25 f1.4 and a 42.4 f1.2, very good ones.
Voigtlander makes several f0.5 lenses for m4/3 mount, big and expensive.
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It seems as if it's a rare lens indeed in the m4/3 lineup that is faster than f1.8. None of the M.Zuiko line is. Is there something that just makes it real hard to get to f1.4?
Panasonic has a lot of 1.7 lenses :-) for marketing purposes to be a little faster than 1.8 from Olympus... but if you need faster primes there are Panasonic 25/1.4 or 42.5/1.2 for example with AF.
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A fast lens is still a fast lens. Panasonic makes a 25 f1.4 and a 42.4 f1.2, very good ones.
Voigtlander makes several f0.5 lenses for m4/3 mount, big and expensive.
True, of course.
The "problem" I have with those is that they carry extra weight, size and cost to get OIS on the Panasonic systems. An M.Zuiko PRO 42.5mm f1.2 wouldn't need that.
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The "problem" I have with those is that they carry extra weight, size and cost to get OIS on the Panasonic systems.
they do not = see for example Panasonic 42.5/1.7 with OIS vs Olympus 45/1.8... what they carry indeed is market price premium when there is no direct competition... and when competition is available there is no real difference in price and as you can see in weight/size to speak about.
(http://i2.wp.com/www.mirrorlessons.com/wp-content/uploads/2015/06/Panasonic-42.5mm-1.7-vs-Olympus-45mm-1.8-product-1.jpg)
PS: and 25/1.4 does not have any OIS at all.
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True, of course.
The "problem" I have with those is that they carry extra weight, size and cost to get OIS on the Panasonic systems. An M.Zuiko PRO 42.5mm f1.2 wouldn't need that.
The Voigts are f0.95, not f0.5, my bad mistake... these are large and heavy, once you go beyond f1.4, lenses are bigger...
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they do not = see for example Panasonic 42.5/1.7 with OIS vs Olympus 45/1.8... what they carry indeed is market price premium when there is no direct competition... and when competition is available there is no real difference in price and as you can see in weight/size to speak about.
Interesting! I guess I was reacting more to the larger aperture, creating a larger lens, as expected. I thought the OIS would be adding even more, but it looks as if it does not have to.
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Sensor is smaller than full frame which means that the f stop is smaller.
If anything, smaller sensors often carry surprisingly large f stops.
If we try to compare the equivalent aperture, i.e. the aperture that will give similar DOF, diffraction and light at the sensor, smaller sensor cameras come out quite poorly. My RX100 max aperture of f/1.8 is comparable to a measly 1/(1.8x2.7) = 1/4.9 for 24x36 cameras. My cellphones f/2.0 becomes comparable to a f/11.3 for 24x36 cameras.
-h
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Interesting! I guess I was reacting more to the larger aperture, creating a larger lens, as expected. I thought the OIS would be adding even more, but it looks as if it does not have to.
pictures of OIS solutions on internet when lens is teared apart do not indicate any significant contribution to the size or weight of the lens ... more so m43 lens when optics is lesser in size than FF.
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but what is important - if you use Olympus body then there are reasons to use Olympus lenses - there were topics @ dpreview illustrating that Panasonic lenses do not filter some spectrum close to UV counting on sensor toppings to do the job and Olympus does count on lenses... so when you mount Panasonic lens on Olympus body in certain conditions you can have ill effects - do search m43 section of dpreview forums...
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Even if the lenses are made fast, lets not forget that the light gathering is still at the rated speed. So having an f/1.8 lens or faster means a giant pain to use in bright daylight wide open. You will definitely be at the upper limits of shutter speed considering the low ISO on these cameras is generally 200. I personally don't like carrying around screw-on ND filters unless I really really need to.
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the low ISO on these cameras is generally 200.
used to be, nowadays, since 16mp generations of Sony & Panasonic sensors (as in GH3/GH4, E-M1, etc) it is below SSat ISO 100
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Even if the lenses are made fast, lets not forget that the light gathering is still at the rated speed. So having an f/1.8 lens or faster means a giant pain to use in bright daylight wide open. You will definitely be at the upper limits of shutter speed considering the low ISO on these cameras is generally 200. I personally don't like carrying around screw-on ND filters unless I really really need to.
Is it any harder to reduce aperture on large-aperture lenses than on smaller-aperture lenses?
-h
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My E-m1 is base ISO 200. As are the other olympus cameras ive seen. There is a "pull" or "low" iso setting...but that is just a modified 200 even if it says its 100. You loose dynamic range. The highlights clip way faster. I generally like the most data I can get from the sensor, and that's usually only found at the lowest true ISO. (unless im totally wrong!)
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My E-m1 is base ISO 200. As are the other olympus cameras ive seen. There is a "pull" or "low" iso setting...but that is just a modified 200 even if it says its 100. You loose dynamic range. The highlights clip way faster. I generally like the most data I can get from the sensor, and that's usually only found at the lowest true ISO. (unless im totally wrong!)
I'm not personally sure of what the E-M1 does to get to 100 ISO. It appears that they might get somewhat better dynamic range at 100 vs. 200.
But I do know that all cameras lose dynamic range as you increase ISO.
There are some nice charts on DxOMark that show the effect:
http://www.dxomark.com/Cameras/Olympus/OM-D-E-M1---Measurements
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My E-m1 is base ISO 200.
that is a nominal ISO, based on the brightness obtained during raw conversion to OOC JPG... same Panasonic sensor in GH4 implementation has SSat ISO = 88 @ nominal ISO100 and SSat ISO 122 @ nominal ISO200 in Olympus implementation in E-M1 - that's what counts for a raw shooter.
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that is a nominal ISO, based on the brightness obtained during raw conversion to OOC JPG... same Panasonic sensor in GH4 implementation has SSat ISO = 88 @ nominal ISO100 and SSat ISO 122 @ nominal ISO200 in Olympus implementation in E-M1 - that's what counts for a raw shooter.
That agrees with DxOMark's measurements. Rated ISO 200 = Measured ISO 122.
For whatever that's worth. :)
Their measurements get progressively farther "off": Rated ISO 6400 = Measured ISO 3870. It makes the indicated ISO more of a reference than an absolute.
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It seems as if it's a rare lens indeed in the m4/3 lineup that is faster than f1.8. None of the M.Zuiko line is. Is there something that just makes it real hard to get to f1.4?
IMO f/1.8 (or 1.7) represents a sweet spot where you get speed and resolving capability while keeping lens size relatively compact. Faster lenses like the Voigtländers aren't really that much faster in terms of light-gathering ability (or, maybe more accurately, in terms of the sensor's ability to make use of the extra light gathered). Based on my own use of the Voigts you gain ~1 t-stop of effective speed between f/1.7 and f/0.95. You also get softer, hazier images along with that extra speed…which I like as an effect while realizing most folks don't. Panasonic's 42.5/1.2 is a good performer wide open but it comes with a significant weight/bulk increase over the tiny Oly 45/1.8.
-Dave-
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Voiglander f0.95 (http://www.stevehuffphoto.com/2011/02/28/the-voigtlander-f0-95-25mm-micro-43-lens-review-by-david-babsky/).
Cheer,
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It seems as if it's a rare lens indeed in the m4/3 lineup that is faster than f1.8. None of the M.Zuiko line is. Is there something that just makes it real hard to get to f1.4?
No reason at all. Why, do you want one?
Lumix 25/1.4
Leica DG 42.5/1.2
Voigtlander 10.5/0.95
Voigtlander 17.5/0.95
Voigtlander 25/0.95
Voigtlander 42.5/0.95
I don't see many Fuji's faster than f/1.2. Do you think there is something makes it real hard?
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No reason at all. Why, do you want one?
Lumix 25/1.4
Leica DG 42.5/1.2
Voigtlander 10.5/0.95
Voigtlander 17.5/0.95
Voigtlander 25/0.95
Voigtlander 42.5/0.95
I don't see many Fuji's faster than f/1.2. Do you think there is something makes it real hard?
Snark aside, these are, of course, viable choices. But only the first two ate auto-focus, correct?
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My point being made, though. There is clearly nothing stopping m43 lenses at f/1.8, because they don't stop at f/1.8. The question was ill-informed from the outset.
But it certainly is answered.
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I'm not personally sure of what the E-M1 does to get to 100 ISO. It appears that they might get somewhat better dynamic range at 100 vs. 200.
But I do know that all cameras lose dynamic range as you increase ISO.
There are some nice charts on DxOMark that show the effect:
http://www.dxomark.com/Cameras/Olympus/OM-D-E-M1---Measurements
Olympus camera's ISO100 is one of the strangest things in the digital camera industry. Unlike other camera manufacturers (Canon, Nikon), which implement ISO50 using the same ISO100 gain with an extra clandestine software exposure correction by -1EV (this doesn't prevent from blowing highlights since metering for ISO50 and capturing at ISO100 means 1 stop of overexposure), Olympus' ISO100 works at a different gain than ISO200, in fact it works at a nonsense ISO250 gain (1/3EV over the expected ISO200 gain), blowing even more highlights than the Canon and Nikon cameras in their low ISO modes.
If DxOMark would plot correctly Olympus' ISO100, it would fall as follows:
(http://www.guillermoluijk.com/article/lowiso/dxomark.png)
This means that if you shoot at ISO100 on an Olympus camera according to the camera meter, you can loose up to 1+1/3EV in the highlights vs metering and shooting at ISO200. A real example here:
(http://www.guillermoluijk.com/article/lowiso/iso200_clipping.jpg)
(http://www.guillermoluijk.com/article/lowiso/isolow_clipping.jpg)
RAW histograms of the previous shots (the ISO200 RAW file holds 1,33EV more information in the highlights):
(http://www.guillermoluijk.com/article/lowiso/histosmaz.gif)
I have studied this in deep and can assure it's like that:
http://www.guillermoluijk.com/article/lowiso/index.htm (http://www.guillermoluijk.com/article/lowiso/index.htm)
Regards