Tamerlin wrote:
I agree -- but also, building sensors in multiple layers is another nightmare, simply because every layer requires another pass through the process, which adds to cost... and combine that with the fact that the Foveon has its read circuitry on the back of the chip on the edges like most other sensors, and now suddenly you need MORE layers...
I only responded that way to the statement of Foveon being dumb because it's equivalent to saying we shouldn't bother climbing Mount Rainier, because it's hard.
I don't know for sure, but I'd expect so; being clever doesn't get them out of dealing with the same physics as everyone else
They do now, but Intel started off as a puny little upstart with a crappy chip. Intel wasn't a particularly large company as far as semiconductor manufacturers go when they started using bicMOS manufacturing. And AMD isn't exactly flush with cash, yet they're actually implementing immersion lithogrphy, which no one else had been able to do in a high-volume fab...
That's probably why Sigma made the DP-1 and bought Foveon; if Sigma can make enough sales volume with point and shoot cameras using Foveon sensors, they can start making some gains from economies of scale. That's obviously a big if and still no guarantee, of course....Show more →
Actually after the SD9 and SD10 Foveon could no longer afford to produce SD14 sensors at National Semiconductor, not least because of the comparatively tiny and hence highly expensive Foveon sensor production runs so they farmed it out to a cheaper far east outfit called Dongbu Electronics.
Given how much money Foveon lost on wasting their time trying to get into the mobile phone camera sensor market, a total failure BTW, it did'nt help inspire confidence in Foveons investors and many decided to pull out.
This left Foveon despiterately cash strapped and apparently Donbu are still owned lots of money which Foveon simply could'nt afford to pay them.
This dire situation was the only reason they considered selling the company and Sigma only bought Foveon to secure a supply of sensors for their up and coming DP2 and SD15 projects...NOT to allow them to produce larger sensors. If Foveon had declared themselves bankrupt the DP2 and SD15 projects would have been doomed so Sigma had NO choice...It HAD to buy Foveon, even if it was'nt exactly a good financial investment on paper.
Will there ever be a bigger/higher res Foveon X3 sensor now that Sigma hold the reigns of power?...Personally, I dought it, but if there is then I would'nt expect to see such a project come to fruition for at least another 3 years or so...About the same time Sigma launches the DP2 and SD15's successors, going by the rate Sigma releases new camera models.
Alf Beharie wrote:
Actually after the SD9 and SD10 Foveon could no longer afford to produce SD14 sensors at National Semiconductor, not least because of the comparatively tiny and hence highly expensive Foveon sensor production runs so they farmed it out to a cheaper far east outfit called Dongbu Electronics.
Some of the those eastern fabs are not only the biggest, but also the best, like Samsung, TSMC, and UMC... but Donbu definitely isn't among the elite... it's very unlikely that they have access to state of the art fab technology like what the big boys have.
Given how much money Foveon lost on wasting their time trying to get into the mobile phone camera sensor market, a total failure BTW, it did'nt help inspire confidence in Foveons investors and many decided to pull out.
That I don't understand. I can understand wanting that volume, but a sophisticated sensor in a cell phone camera just doesn't make any sense.
Will there ever be a bigger/higher res Foveon X3 sensor now that Sigma hold the reigns of power?...Personally, I dought it, but if there is then I would'nt expect to see such a project come to fruition for at least another 3 years or so...About the same time Sigma launches the DP2 and SD15's successors, going by the rate Sigma releases new camera models.
I personally hope that they pull it off, because I still think that it's the most promising sensor technology out there right now, but I'm not exactly holding my breath. I have a feeling that I'll be able to get a BetterLight before Foveons are available in larger formats, and BetterLight isn't exactly the sort of product that's going to come down in price in a hurry (their market's much too small to gain enough economies of scale).
Alf Beharie wrote:
Will there ever be a bigger/higher res Foveon X3 sensor now that Sigma hold the reigns of power?...Personally, I dought it, but if there is then I would'nt expect to see such a project come to fruition for at least another 3 years or so...About the same time Sigma launches the DP2 and SD15's successors, going by the rate Sigma releases new camera models.
Well, Sigma did keep the chip design team around after the acquisition and if you go to Foveon's web-site they have job listings for chip designers and test techs. So clearly they are designing something. Furthermore, my understanding was the cell stuff died awhile ago and transition to Sigma related development began before the acquisition announcement. So personally I would expect something new. That said, who knows how fast or slow it will happen. As you say, things have never been super fast over at Sigma.
veroman wrote:
I speculated about all this when I owned a Sigma SD9 and had high hopes for at least a 1.3 crop as Foveon advanced the design for Sigma. But they really didn't advance it very much during the 5 or 6 years since its introduction. The SD14 has the same sensor as all of the previous models (there were only 2) with just a few more MP crammed in there.
So why no full-frame or even 1.6 or 1.3 crop? I personally have concluded that there three issues that prevent them making a Foveon sensor of larger physical size:
1) Too much heat generated by the sensor, which results in dramatically increased noise
2) Too much data being passed through, resulting in a painfully slow camera that simply could not compete with even a Canon x-series. Frame-rate would probably be something 1 every two or three seconds. One thing about the Foveon sensor: it does produce very large files due to the amount of data and detail each file contains. I think Sigma would have to invent a new kind of buffer to accommodate the data transferred by a true 20MP, full frame Foveon. In fact, I do think that this is the primary reason they've kept the sensor small to this point.
3) The cost of producing a 20MP full frame Foveon sensor may be prohibitive, perhaps resulting in a camera costing as much as a Canon 1Ds III, but without most of the 1Ds III features. Would you buy an $8,000 bare-bones camera from Sigma just because it was 20MP and full frame?
I believe there is a 4th reason, that being because the sensors are "stacked" the Foveon sensor is much more affected by off-axis light rays and therefore more suppeptable to vignetting in a full frame. Keeping the sensor small prevents vignetting to an extent by not allowing the light rays to hit the sensor at much of an angle.
And Yes, I would purchase a "Bare Bones" Full Frame Foveon camera ( FPS is irrelavant in my type of photography ) - IF the sensor actually displays higher resolution and lack of morie patterns when compared to a bayer sensor. The only other item on the camera would have to be the availability in other mounts ( Nikon F or Canon EOS ) as I would not want to be stuck having to use Sigma lenses.
ACElkins wrote:
I believe there is a 4th reason, that being because the sensors are "stacked" the Foveon sensor is much more affected by off-axis light rays and therefore more suppeptable to vignetting in a full frame. Keeping the sensor small prevents vignetting to an extent by not allowing the light rays to hit the sensor at much of an angle.
And Yes, I would purchase a "Bare Bones" Full Frame Foveon camera ( FPS is irrelavant in my type of photography ) - IF the sensor actually displays higher resolution and lack of morie patterns when compared to a bayer sensor. The only other item on the camera would have to be the availability in other mounts ( Nikon F or Canon EOS ) as I would not want to be stuck having to use Sigma lenses.
Your would'nt be...I use lenses ranging from 14mm to 1100mm on my SD14 and only one is a Sigma lens, the rest are Carl Zeiss, Canon, Nikon, Tamron, Tokina etc.
Alf Beharie wrote:
Your would'nt be...I use lenses ranging from 14mm to 1100mm on my SD14 and only one is a Sigma lens, the rest are Carl Zeiss, Canon, Nikon, Tamron, Tokina etc.
Adaptors are available. SA mount is essentially EF mount with the bayonet replaced by a lightly modified K mount bayonet, so adaptation of many mounts is fairly easy.
mawz wrote:
Adaptors are available. SA mount is essentially EF mount with the bayonet replaced by a lightly modified K mount bayonet, so adaptation of many mounts is fairly easy.
Had not realized the Sigma mount allows other lenses to be used via adapters, must be fairly similar to EOS mount. However must be some other difference either in backfocus distance or mount diameter as it seems there has to be major modifications to make the sigma mount work with Leica R lenses.
ACElkins wrote:
Had not realized the Sigma mount allows other lenses to be used via adapters, must be fairly similar to EOS mount. However must be some other difference either in backfocus distance or mount diameter as it seems there has to be major modifications to make the sigma mount work with Leica R lenses.
Mount diameter, SA mount uses a lightly modified K bayonet with EF register and lens communication protocol. The K bayonet has a notably smaller throat than EF, making some adaptations much more difficult.
ACElkins wrote:
Had not realized the Sigma mount allows other lenses to be used via adapters, must be fairly similar to EOS mount. However must be some other difference either in backfocus distance or mount diameter as it seems there has to be major modifications to make the sigma mount work with Leica R lenses.
The registration distance of SA is the same as EF (44mm) but the bayonet is smaller is diameter, a tad larger in diameter than PK mount in fact but the Bayonet is similar enough to PK that PK lenses can be fitted onto SA mount cameras, as long as you remove the protruding parts (The AA lever and AA lever protector moulding on the bezel ring), with varying degrees of play in the fit.
Nikon F lenses can be fitted onto the SD9 and SD10 via the Japanese JTAT Nikon-SA adapter but that adapter wont work on the SD14 or the upcoming SD15.
For the SD14 and SD15 you either use the non-optical Roxsen Nikon lens-M42 camera adapter plus an M42 adapter (For close ups and macros only) or the optical Roxsen Nikon lens-PK adapter (For infinity shots).
The former adapter combo is best for Nikon Micro Nikkors because even though you cant focus to infinity it gives a magnification advantage and there are no optical elements in line to ruin image quality...Its also cheaper than the latter adapter.
For fast, non-Micro Nikkors, Contax Carl Zeiss, Olympus OM and Canon FL lenses that I wanted to use at infinity without the need for an adapter I decided the easier option was to convert them to SA mount. I used the SA mounting plates off my two Sigma lenses, bought another 5 SA mounting plates from one Sigma user and obtained another 4 off another.
I have also converted a Carl Zeiss 50mm f1.7 Planar T* PK mount.
A C/Y mount Vivitar 35-200mm f3-f4.5 macro zoom to M42 mount and a Canon FD mount Sigma 14mm f3.5 (rectalinear) to M42 mount.
Tamron Adaptall lenses can be used via an M42-Adaptall adapter plus an M42-SA adapter or a PK-adaptall adapter...The M42 option is best as it ensures a perfect fit via an M42-SA adapter, wheras the Pentax adapter may need modding and it will have a comparatively sloppy fit.
T mount lenses can be used via a T2-M42 adapter or a T2-PK adapter. I use the latter on my MTO 1000A 1100mm f10.5.
P6 mount lenses, like the Carl Zeiss Jena 180mm f2.8 Olympic Sonnar, can be used via a P6-M42 adapter plus an M42 adapter.
I made my own adapter for Mamiya 645-SA.
If my supply of SA mounting plates ever run out, I'll simply use M42-SA adapters. instead.
Alf, great to see you back on FM forum - now i can show you and the rest of us who interested in the FL canon 55 vs rokkor 58 1.2 comparison. I have converted sigma sd14 to EOS canon mount, so it is possible to compare both on sigma sd14 as well.
Interesting results!...The exact point of focus was not the same, the Rokkor was focussed closer to the camera than the FL (Evidence for this is the OOF highlights being smaller on the FL samples than the Rokkor samples).
Taking this into account though I'd have to say there is'nt really much between the two. Strange how the FL thumbnails look more contrasty than the Rokkor thumbnails but there is'nt really a noticable difference in the larger samples.(?)
Did you use an optical FL/FD-EF adapter to mount the FL on your SD14?...I dont need an adapter to mount mine and therefore the image quality is not compromised by having additional optical elements between the camera and lens.
BTW, how long did it take you to convert your SD14 to EF mount?...I expect the hardest bit was fitting the EF electical block?
Alf, focus was in the center of the frame and shooting position was the same but 3mm focal length difference makes the OOF highlights bigger\smaller. Since i have modified FL 55 to ef mount and i have sd14 also with ef mount - i can use all ef bayonet lenses on my sd14 directly as if it would be eos camera.
I think one or two days would be enough to convert sd14 to ef. Previously the hardest part was full mirror box disassemble in order to put el. cable into the socket http://www.pbase.com/bigflat/sd14_disassembly&page=all, but i have found the way how to avoid this.
That sounds like an awfull lot of reall fiddly work...Rather you than me!
As you have both I wonder what is your personal opinion of the FL vs Rokkor?...The FL is best between f4-f5.6, and I should imagine the Rokkor is too so a comparison at those apertures would be very interesting.
