itai195 wrote:
So I'm still left wondering if there is a decent 35mm RF lens to use on the A7... Keep hearing mixed reports about the Leicas, and the CV 35/1.2 is a little larger than I'd like but it looks like it works okay?
"We are currently working on our next project, the wide-angle IBEGON lens. With Sony releasing the new full-frame mirrorless A7/A7R camera, we have designed a high-speed telephoto APO mirror lens called the IBECAT, named for its sharp image capture, its lightweight construction and fast glass. Additional lenses are in development for full frame mirrorless cameras, including a tilt-shift lens and a compact fixed focal length lens."
philip_pj wrote:
A 3rd group Rich, a large one numerically - those with or happy to use beautiful legacy SLR lenses bought cheap, like Pentax and Canon FD, Contax etc. at all FLs until Zeiss really deliver the goods in native FE next year. A perfect mix and match for many of us.
+1
If it has already proven itself on 24x36 digital before ... imo, there's little reason for it to not perform well on 24x36 again.
The registration distance being further back (typically) than RF glass tends to make for more favorable angles of incidence. It comes as little surprise to me that the Leica R 28 and Leica R 19 are renowned as superior WA/UWA optics. The Leica R being some of the farthest back (Tamron Adaptall, also) registration of the SLR glass.
Starting farther back means you may have a bit of difference in contrast (how terrible is that) compared to the RF glass that starts so much closer to the film plane (somewhat slightly akin to how using tubes lowers contrast or MF glass is lower contrast than RF glass), but your Zone C angles of incidence are are going to be much more sensor-friendly.
If you want smokin' hot central contrast I'd go for the RF / M's, particularly if you can accept/tolerate shortcomings in Zone C. If you want great full frame coverage, I'd go for the SLR glass ranging from Oly's to Distagon's to Leica R's (et al). The TS-E's also start from farther away optically and have every reason to play nice in Zone C as well (+ the larger image circle).
Imo, it is easier to bump contrast a touch than it is to correct for smearing, vignetting and color shift. Are those fewer ounces and centimeters of weight and size really worth all that to achieve varying degrees of usability? For some, the answer is emphatically yes. For others, not so much. We'll see what the native glass brings, but I wouldn't expect it to be as small as the RF glass if it wants to perform well across the entire 24x36 frame ... imo, the trig just doesn't support it.
As always ... when it comes to WA/UWA, choose your poison(s).
turnstyle wrote:
Can you cite any examples of lenses that work on A7r but not A7? I've certainly seen examples the other way around. (Or was that possibly just a typo?) Or did you possibly mean "where it may work on one A7r and not another"?)
It was probably a typo, or not clear, but the intent of my comment was for both A7/A7r there does not appear to be any issues with R and DSLR lenses. The comparison with M lenses on the A7 and A7r has somewhat of a mine field. Statements by Sony to the contrary, and the variability of results we are seeing just comparing M lenses on A7r's. There are a number of lenses that do work well, but it not the range I was hoping for
I have just read on the LUF forums, that someone has noted that the Metabones works better than the Novaflex adapter!! I have both, and I find the tolerances better with the Metabones from Sony, and there maybe the issue of internal dimensions that may affect some of the corner smearing? Interesting!
charles.K wrote:
I have just read on the LUF forums, that someone has noted that the Metabones works better than the Novaflex adapter!! I have both, and I find the tolerances better with the Metabones from Sony, and there maybe the issue of internal dimensions that may affect some of the corner smearing? Interesting!
Charles,
I saw that too. Interesting about the Leica M to NEX adapters but this may be reversed with the Novoflex being better for the Leica R to NEX adapters (from what I have seen on-line, but I am not sure if those were consistent for the results).
charles.K wrote:
I have just read on the LUF forums, that someone has noted that the Metabones works better than the Novaflex adapter!! I have both, and I find the tolerances better with the Metabones from Sony, and there maybe the issue of internal dimensions that may affect some of the corner smearing? Interesting!
Sample variation on these things is so high (far higher than it should be given their price - Fotodiox's $40 adapters should have the kind of tolerances I'm seeing from Metabones $90 ones) that such an assessment is meaningless unless his results are the average of testing half a dozen or more of each brand.
Dec 14, 2013 at 09:59 PM
Steve Spencer Offline • • • • • • • Upload & Sell: On
philip_pj wrote:
A 3rd group Rich, a large one numerically - those with or happy to use beautiful legacy SLR lenses bought cheap, like Pentax and Canon FD, Contax etc. at all FLs until Zeiss really deliver the goods in native FE next year. A perfect mix and match for many of us.
It's good the Leicaphiles one percenters are numerically as few as their volume is large. Mainstream consumers, upshifters from APS-C and m43, cross shifters from DSLR will quickly appreciate the a7/r series.
As expected I found just now that the 21mm Distagon is breathtaking on the 36Mp model, I really don't how it avoided the dreaded 'Sony smear' TM../satire..
..and 1/50s are no problem at all hand held; and the shutter is not mushy or indistinct but works just fine, very nice in fact; and the shutter sound is very reassuring, you adjust to it fast; I saw no 11x jaggies; it's very easy to handhold as the adapter provides a good support base for the left hand; the 36mp files open out into .psd files very nicely, say no posterisation. No bad options here.
Anyone know what Lloyd Chambers complaint du jour is today? He has been hard at it, has he exhausted himself already? If so I am disappointed in him. I am enjoying shooting these 'issues' down right now. Where is Max when you need him...what else - yeah, tonal gradations are very lifelike indeed, but you need more attenton to histo tuning. Files are malleable like the RX1/a99. EVF is even better than RX1, noticably so in fact, very nice in all light tried so far. WB is fussy.
New lens maker sounds great, Jeff. More the merrier....Show more →
This second or third group (i.e., those who do not already own RF lenses) is likely to be diverse. I will very likely get one of these cameras (probably the A7r), but I am not in a big hurry. When and if I do I won't be too upset about the RF lenses that don't work well. I have a 5D MKII right now and it can use a lot of lenses, but even without the RF wides that don't work, I am excited about using lenses that will work on the Sony camera and don't work or only would work with major surgery on my 5D MKII. For example at 35mm I will probably pick up a Minolta MD 35 f/1.8--a lens I loved on my crop sensor Canon, but doesn't work past about 3 meters on FF. I am likely to also pick up a Voigtlander 35 f/1.2--a rangefinder that seems to work well and although considered big is about half the size of my ZE 35mm f/1.4, and when I save up enough money I would love to have a Leica M 35 f/1.4 ASPH (non-FLE) that I think will work well and is both tiny and a great performer. I can also use a Canon nFD 85 f/1.2L and I will likely get a Pentax 77 f/1.8 Limited (a very nice and tiny lens that would require surgery on Canon). So for those of us that do not currently own a bunch of RF lenses, the glass is at least half full. The cameras seem to offer a whole host of possibilities and if some of the wide angle RF lenses don't work that is too bad, but it still feels like there are a lot of quality lenses to work with. Much, much more that with any DSLR.
p.147 #11 · A7/A7r - performance with WA RF lenses
A7R <-Novoflex-> Leica Summilux 35 aspherical II
1/25th @ f/1.4
ISO 3200
For sure, this lens is astoundingly good wide open. I don't know what specific things about the lightpost provoked the flare at the upper corners. I saw it in the digital finder, though. So, I wasn't deceived.
p.147 #12 · A7/A7r - performance with WA RF lenses
Here is a ZM15 shot in full-stop increments, starting wide open at f/2.8 and shot at infinity without the center-spot filter.
I'm not really much of an image analyst, I just want stuff to look good and that means getting best possible raw files and optical solution to start from. Having said that, this blue sky shot won't tell us much about smearing in the corners.
But what's really odd, is this light piss-yellow bar at the top of the images. It seems to get worse as I stop down. For the moment, I'm stumped.
p.147 #13 · A7/A7r - performance with WA RF lenses
Please pardon my layman's question. If I shoot wide open, the dimension of the image is not restricted by the blades, whereas if I stop down masssively, I see just a small roundish hole for the light to hit the sensor.
If I translate this into light ray angles hitting the sensor, my instinct (I am no engineer) says that the angles must be more acute from the small centre hole to the side of the sensor than if the lens is wide open. Yet I know that the smearing problems are at their worst wide open, meaning that the angles are at their most acute wide open as well, which means the opposite of what my instinct suggests is true. So where am I getting it wrong. Why are the angles more acute wide open?
p.147 #14 · A7/A7r - performance with WA RF lenses
philber wrote:
Why are the angles more acute wide open?
If I had to guess from a conceptual level, I would offer that one can trace the rays of a wide-angle lens, just as the designers do. But if one restricts that flow of light near the trunk, which is somewhat close to the sensor, I would hazard a guess that the most oblique stuff is bouncing off the blades and doesn't get into "Klub Fotowell" (cue populist Pacha/Ibiza mix) because the diaphragm bouncer says those photons are wearing the wrong shoes.
p.147 #15 · A7/A7r - performance with WA RF lenses
philber wrote:
Please pardon my layman's question. If I shoot wide open, the dimension of the image is not restricted by the blades, whereas if I stop down masssively, I see just a small roundish hole for the light to hit the sensor.
If I translate this into light ray angles hitting the sensor, my instinct (I am no engineer) says that the angles must be more acute from the small centre hole to the side of the sensor than if the lens is wide open. Yet I know that the smearing problems are at their worst wide open, meaning that the angles are at their most acute wide open as well, which means the opposite of what my instinct suggests is true. So where am I getting it wrong. Why are the angles more acute wide open?...Show more →
the problem with your thinking is that light at a given corner of the sensor comes from both sides of the hole (iris). light coming from the near side of the hole is at a steeper angle stopped down but light coming from the far side of the hole is at a steeper angle wide open. no matter the aperture it's always light coming from the far side of the hole that comes at the steepest angle.
p.147 #17 · A7/A7r - performance with WA RF lenses
philber wrote:
Thanks, Sirimiri. Much appreciated!
Remember, you're reading my ramblings...they are nothing more!
Today I also shot (during Ingress gaps) some images that I hope serve to get a better idea of the center-to-edge performance of the Zeiss Distagon 15mm (ZM).
I'd wager from my 100% views that there may be some edge smearing at 15mm. Part of my problem is that I don't necessarily have another strict 15mm to compare it to. For sure, the Canon 17mm and 24mm lenses are *very* good in the corners, even from wide open. But those are different lenses for a different system.
I do note that the odd "piss-yellow" block is present at the top of the frame. I'm still thinking about this one...
(I uploaded these at 1500x1000, I hope it stuck)
shutter speed in full stops to match f-stop variations, handheld at ISO 100, sans center-spot filter.
p.147 #18 · A7/A7r - performance with WA RF lenses
sirimiri; thank you for the images. I have a question: how are they processed? Maybe you can describe that in a few words. I have been part-time mentally engaged in the banding (or whatever it is) we see in the sky, maybe since sebboh showed us images with the problem but taken with the R1X. Raw, colour space, jpg compression?
The p-yellow block at the top is ugly but interesting. I have no idea. Maybe, how does this lens handle flare? See how it increases as you stop down.
p.147 #19 · A7/A7r - performance with WA RF lenses
Steve Spencer wrote:
(...)
For example at 35mm I will probably pick up a Minolta MD 35 f/1.8--a lens I loved on my crop sensor Canon, but doesn't work past about 3 meters on FF. I am likely to also pick up a Voigtlander 35 f/1.2--a rangefinder that seems to work well and although considered big is about half the size of my ZE 35mm f/1.4, and when I save up enough money I would love to have a Leica M 35 f/1.4 ASPH (non-FLE) that I think will work well and is both tiny and a great performer. (...)
Hi,
I have a Minolta MD 35/1.8 in the mail. Now you are saying it doesn't work from 3m and up? Oops. But it worked very well at longer distances on film, didn't it?
The CV35/1.2 is OK. The FA31/1.8 Limited is OK. None of them perfect, they will both require more PP than the RX1 (not always but in many situations). The Summilux-M 35/1.4 ASPH (non-FLE) make very beautiful images but doesn't work for all situations. The focus shift may be annoying or not depending on your "shoot-flow".
I'll try the Minolta when it arrives. If it doesn't work I'll have to go back to the Voigtländer 35/1.2 or skip the A7 for for 35mm focal length and just stick to my RX1.
