p.3 #1 · RhinoCam: 645 Medium Format back with Sony NEX body!
douglasf13 wrote:
I don't know, the Voigtlander 35/1.2 is pretty good wide open, and the Mamiya 80/1.9 isn't particularly great at the edges on 35mm wide open, either, let alone on 645. I'm not sure that it's any more difficult to build a f1.2 lens for 35mm than it is to build a f1.9 lens for 645, is it?
Ok then try a 58mm f/.8 for full frame . 4x5 uber alles....except 8x10...and larger...
p.3 #2 · RhinoCam: 645 Medium Format back with Sony NEX body!
douglasf13 wrote:
I don't know, the Voigtlander 35/1.2 is pretty good wide open, and the Mamiya 80/1.9 isn't particularly great at the edges on 35mm wide open, either, let alone on 645. I'm not sure that it's any more difficult to build a f1.2 lens for 35mm than it is to build a f1.9 lens for 645, is it?
Yes, building an f1.2 lens is generally a lot harder than an f2 lens. Low f-number requires thicker, more strongly curved elements, where easy-to-make spherical lenses deviate more from "ideal" aspherical shapes. There are a whole host of off-axis aberrations that blow up quickly in faster optics.
With fancy enough optics, it's not impossible to build a decent fast 35mm lens. The CV 35/1.2 is a $1400 optic with 3 aspherical lens surfaces. The M645 85/1.9 goes for ~$300 used, and is a simple double-gauss design from ages ago. I wish I could find the thread, but I remember someone did recently post a direct comparison between the CV 35/1.2 (wide open) and a 'Blad 85/2.8 on 6x6 film: no contest, the 85/2.8 on 6x6 completely blew away the CV 35/1.2 for sharpness/detail at equal DOF. I don't specifically how the M645 85/1.9 stacks up, but remember that you get an additional advantage (beyond the slower aperture) once you shrink down the larger 645 frame to match 35mm: a lens with lower lp/mm can still provide more lp/image.
p.3 #3 · RhinoCam: 645 Medium Format back with Sony NEX body!
mpmendenhall wrote:
Yes, building an f1.2 lens is generally a lot harder than an f2 lens. Low f-number requires thicker, more strongly curved elements, where easy-to-make spherical lenses deviate more from "ideal" aspherical shapes. There are a whole host of off-axis aberrations that blow up quickly in faster optics.
With fancy enough optics, it's not impossible to build a decent fast 35mm lens. The CV 35/1.2 is a $1400 optic with 3 aspherical lens surfaces. The M645 85/1.9 goes for ~$300 used, and is a simple double-gauss design from ages ago. I wish I could find the thread, but I remember someone did recently post a direct comparison between the CV 35/1.2 (wide open) and a 'Blad 85/2.8 on 6x6 film: no contest, the 85/2.8 on 6x6 completely blew away the CV 35/1.2 for sharpness/detail at equal DOF. I don't specifically how the M645 85/1.9 stacks up, but remember that you get an additional advantage (beyond the slower aperture) once you shrink down the larger 645 frame to match 35mm: a lens with lower lp/mm can still provide more lp/image....Show more →
Good point about the Mamiya design. It is still relatively basic, although I would think that the sheer size difference would be an extra expense.
I agree about the medium format lenses, if we're talking about downsizing 645 to match 35mm. My 80/2.8 is great on my Hasselblads, but not exactly outstanding on my 35mm cameras. Since the smaller formats require more resolution, I would think it possible to get even better performance with this RhinoCam using some of the 35mm lenses out there, since they are often sharper than their medium format counterparts, but, like sebboh mentioned, you can frame the whole shot with the medium format lenses, which is nice. Cool gadget.
p.3 #4 · RhinoCam: 645 Medium Format back with Sony NEX body!
douglasf13 wrote:
Good point about the Mamiya design. It is still relatively basic, although I would think that the sheer size difference would be an extra expense.
I agree about the medium format lenses, if we're talking about downsizing 645 to match 35mm. My 80/2.8 is great on my Hasselblads, but not exactly outstanding on my 35mm cameras. Since the smaller formats require more resolution, I would think it possible to get even better performance with this RhinoCam using some of the 35mm lenses out there, since they are often sharper than their medium format counterparts, but, like sebboh mentioned, you can frame the whole shot with the medium format lenses, which is nice. Cool gadget. ...Show more →
Isn't the point of using the MF lenses in this RhinoCam that they are using the entire image circle and moving the camera sensor within that area? 35mm lenses wouldn't have that option, it would just be a pano mount in that case.
p.3 #5 · RhinoCam: 645 Medium Format back with Sony NEX body!
jctriguy wrote:
Isn't the point of using the MF lenses in this RhinoCam that they are using the entire image circle and moving the camera sensor within that area? 35mm lenses wouldn't have that option, it would just be a pano mount in that case.
Yep, that's what I was referring to in my last line above.
p.3 #6 · RhinoCam: 645 Medium Format back with Sony NEX body!
douglasf13 wrote:
My 80/2.8 is great on my Hasselblads, but not exactly outstanding on my 35mm cameras. Since the smaller formats require more resolution...
I guess it really depends on which lenses you're considering. At common apertures on FF DSLR, my Mamiya C 80/2.8N is just as sharp as, or sharper than, the Contax Zeiss Planar 85/1.4, Canon 85/1.2L II, and Leica-R 90/2. I've found similar results with M645 lenses at 35mm, 55mm, 120mm, 150mm, 200mm, and 300mm focal lengths.
I also found that the Hassy Distagon T* CF 50/4 and Planar CF T* 80/2.8 had similar, superior performance, in that they were as good as many of the best 35mm format lenses. I decided to stick with M645 lenses because they're generally smaller, lighter, and less expensive.
p.3 #7 · RhinoCam: 645 Medium Format back with Sony NEX body!
Make that back plate fitting a 6*7 Mamiya lens and I am in. Apparently it should accommodate for more pictures per Lens Frame, hence a higher pixel count, while using some of the best glass..
p.3 #9 · RhinoCam: 645 Medium Format back with Sony NEX body!
EB-1 wrote:
Wouldn't it be better to start with an FX sensor that there would be less frames to stitch?
EBH
Yes, assuming super-too-much-resolution isn't your goal. However, I suspect the mechanics of most FX sensor cameras --- specifically the protruding mirror box and grip --- would make this hard to work. You can squeeze a small shift adapter between the lens and mount, but not the large extended plate design that this uses, which only works with a camera with a flatter front and/or more distance from the mount flange (typical mirrorless).
p.3 #10 · RhinoCam: 645 Medium Format back with Sony NEX body!
EB-1 wrote:
Wouldn't it be better to start with an FX sensor that there would be less frames to stitch?
EBH
Yes the rumoured full frame NEX9 would be ideal for this, you could cover the 645 frame with overlap in just four images, massively reducing the time taken for a shot and therefore the chance of it being ruined by movement.
You could also get a near 645 image in just two shots.
p.3 #11 · RhinoCam: 645 Medium Format back with Sony NEX body!
mpmendenhall wrote:
The difference is that it's easier to design a sharp/clear/contrasty f1.9 lens that captures lots of detail on a 645 frame, than an f1.2 lens that squeezes the same amount of information into a 35mm frame. Super-fast lenses on 35mm typically have a distinctive "look" at wide apertures: high vignetting, low contrast, soft corners, etc. Now, consider how much better a lens typically is at ~f2 than ~f1.2, then improve the output image more by capturing over a whole 645 instead of 35mm: you get both super-thin DOF, and an extremely clean/sharp/detailed look not possible from the most expensive 35mm-format f1.2 lenses. ...Show more →
I take your point, but being sharper and more contrasty at the same or deeper DOF is not the same as offering shallower DOF.
If you want shallow depth of field using this technique you need to go past MF into 4x5 or 8x10 territory using a radioactive aero Ektar, or a pricey Xenotar 150mm f/2.8. But if you're that much of a shallow depth of field junky then shooting a multirow panorama with nodal head and fast short telephoto on a 35mm DSLR will get even better results at a significantly lower price tag - see the image posted in the first reply in this thread:
Jman13 wrote:
Hey....I've done this handheld on Micro 4/3 with no 'back' before.
Like this image, which is like using a 59mm f/0.9 lens on the RhinoCam, but was taken by merging 64 images on my GH2 with Rokinon 85/1.4. And my file was 465 megapixels!
p.3 #13 · RhinoCam: 645 Medium Format back with Sony NEX body!
I think it's an interesting proposition. Being able to frame the pano before shooting has its merits, though it places a limit on scope. The concerns expressed about timing are true regardless of how you shoot a pano, and this is just a pano tool. Or I guess you could look at it as a digital back with manual shifting multishot, but that still sounds like pano tool to me. However, I don't have any really special MF lenses. Not that the C 50/4, 80/2.8, and 120/5.6 are lousy on the 500, they just aren't anything I feel the need to use on any other camera. So I'm not seeing the value of using it instead of doing a pano the way I do them now.
p.3 #15 · RhinoCam: 645 Medium Format back with Sony NEX body!
steve.chang wrote:
This sounds very true and limited.
looks like it's only 6 frames and it's quick to move. that shouldn't be an issue for clouds or anything except the fastest of changing light. waves or people is another story...
p.3 #16 · RhinoCam: 645 Medium Format back with Sony NEX body!
I was wondering if any of the current owners/users of the Rhinocam could possibly share with us what are the maximum sizes (pixels) that can be achieved with the Rhinocam and Nex-7 in both 645 and pano mode? I have read somewhere that the resulting file would be in the neighbourhood of the 14,000 x 11,000 pixels for the 645 mode, but ignore if that figure is accurate. Also very interested because I want to know what aspect ratio the resulting panorama has.
p.3 #17 · RhinoCam: 645 Medium Format back with Sony NEX body!
645 format is roughly 56x42mm, IIRC, so knowing the sensor size, you can figure out what pixel count that would correspond to. The aspect ratio is 4x3.
p.3 #19 · RhinoCam: 645 Medium Format back with Sony NEX body!
Ben Horne wrote:
Great for shooting at noon when the light doesn't change. :-)
Yes, also when there is no movement in the foliage or any wave action.
Don't get me wrong, a sort-of new tool, but doesn't replace a "real" 4x5 for a number of compositions. But for relatively static scenes, could be useful.
p.3 #20 · RhinoCam: 645 Medium Format back with Sony NEX body!
carstenw wrote:
645 format is roughly 56x42mm, IIRC, so knowing the sensor size, you can figure out what pixel count that would correspond to. The aspect ratio is 4x3.
Thanks Carsten, should have thought that myself in the first place.. That means indeed roughly 14,000 x 11,00 pixels for the resulting stitch. I guess the panoramic format will be something close to the 6x12 format.
. 4x5 uber alles....except 8x10...and larger...
That means indeed roughly 14,000 x 11,00 pixels for the resulting stitch. I guess the panoramic format will be something close to the 6x12 format.