Here is actual test in real life in comparison to Canon 5D Mark III
http://www.eoshd.com/content/9474/p...ster-equipped-nex-7-vs-full-frame-5d-mark-iii
http://www.eoshd.com/content/9474/p...ster-equipped-nex-7-vs-full-frame-5d-mark-iii
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I have been wanting something like this for ages (wide angle converter that's behind the lens)
- Thread starter Meuh
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http://www.eoshd.com/content/9474/p...ster-equipped-nex-7-vs-full-frame-5d-mark-iii
"On the NEX 7 the camera reports the maximum aperture as F1.3 and it is certainly brighter. The difference in exposure that the Speed Booster brings allows me to shoot at ISO 1600 on the NEX 7 where ISO 3200 is required on the 5D Mark III."
Even then it won't be worth it as Pentax FF lens line up is thin. That's adding a lot of cost to the camera body for little gain. Canon and Nikon, on other hand, have large FF lens line up (including full-frame manual focus Zeiss lenses).
Sticking with the K-mount for mirrorless camera itself makes it the number 1 limiting factor.
And there are others who are using Nex-7 with expensive M mount lenses.
And then there are videographers who are using the E-mount FS100 and FS700 in their professional work (and most of them own Canon lenses -- as most of them are previous owners of 5D Mark II). This adapter (especially the Canon to Nex version) is especially designed for those people, and the price (relatively) is very cheap.
Phillip Bloom is perfect example of type of people who would want this adapter .. he is already covering it on his site
http://philipbloom.net/2013/01/13/speedbooster/
FS100 is pretty close to 5D Mark III in price, and the image quality (for video) is way superior than DSLR. That's the market that would be #1 buyers of this adapter.
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Tan68
Veteran Member
At the end of the review, the fellow says "The high end photographic and videography market has really moved towards full frame sensors as the standard… And now… Do we need them?"
I do think the Canon took a prettier picture (color, etc.), but, setting that aside, this adapter looks like an interesting thing...
The point of the adapter must not be focal length equivalency. It is called Speed Booster, after all, and there are APS-C equivalent focal lengths for most lenses (16mm v. 24mm, etc.).
The device does feed more light to the sensor and so it makes lenses, as far as the camera and exposure are concerned, a stop faster. Appearing to the camera as a stop faster lens, the operator has a choice of a faster shutter speed or lower ISO. A stop lower ISO works toward negating the lower noise advantage full frame cameras have.
From the sample pictures, appears the thing reduces depth of field. Not sure how and I don't want to think about it right now.
So, it does seem to, for the most part, convert an APS-C into a full frame with respect to field of view, light gathering ability, and depth of field. Outstanding is how it performs image quality-wise and the real effects of pixel pitch. As I noted, the Canon samples looked prettier, but that may have nothing to do with either sensor size/ability or any unwanted effects added by the adapter and more to do with the Sony camera and its inherent abilities...
This thing is still not a magic bullet. The same arguments between APS-C and FF still exist. Say I am taking a picture with my APS-C + 16mm lens and am happy with my depth of field at f/8. If I use this adapter with a 24mm lens, i would want f/11 or so and use a higher ISO to keep my shutter the same. So, I end up with the same ISO and practically the same field of view and depth of field as I had with my 16mm lens. I know you know this, just pointing out where I think the adapter would be a waste of money for people.
As with FF, where the adapter is nice for wide angle lenses and narrow depth of field. That is pretty hard to come by with APS-C. Other focal lengths enjoy a reduction in depth of field with this adapter, but it is fairly easy to get narrow depth of field on APS-C as the focal length increases.
Ultra thin depth of field and wide angle + narrow depth of field make this thing pretty interesting... It may still have a limited market. I need full frame lenses to use it. I could add the $600 cost to some mirrorless and near the cost of cheap FF.. But the FF is bigger and APS-C has some benefits, too. Oh, conundrum. Why did they make this thing?
As outstanding, when I say image quality, I mean the adapter itself and when I say effects of pixel pitch, I mean the sensor size...
There are wide angle adapters for mobile phones and the picture is still not nice. I realise this adapter is an entirely different beast from adapters strapped to the front of a lens.
The point I am trying to make is that, while the adapter converts three parameters to "FF-like" performance, there is still the difference in sensor size. Set aside any poor performance of the optics built into the adapter, and there may still be some benefits to a larger sensor. Seems this adapter negates most of them, though...
I couldn't guess what the advantages of a larger sensor might still be, but I intuit there would still be some advantages to larger pixels. I think any advantages might be in the 'splitting hairs' category and that the adapter will be satisfactory for most that buy it. But people still looking for the most performance will want the larger sensor...?
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leopold
Forum Pro
I'm not convinced, will have to wait real reviews and not publicity by a lens maker who wants to make money !!!
EOSHD isn't the lens maker, nor is Phillip Bloom
http://philipbloom.net/2013/01/13/speedbooster/
The adapter is shipping soon this month
http://www.metabones.com/sony/ef-e-speed-booster
So will find out how it performs
Most of the early buyers will all be FS100 and FS700 owners, because that's really the main target for the adapter (it's pretty cheap for people who own cameras like FS100 and FS700).
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MightyMike
Forum Pro
Russell, if you can believe that a 1.4x rear tele converter will lose you a stop of light and there is no one arguing that point. you then also have to believe a 0.71x rear wide angle converter will gain you a stop of light. a 35mm F2.0 on FF will give you x amount of light over a given area, that same 35mm F2.0 on APS-C will also give you that same x amount of light over a smaller area. the density of light hasn't changed. however when you take x amount of light on a FF sensor and compress it into a smaller area such as an APS-C sensor you're now all of a sudden increasing the density of that light by a factor of 1.5x (lets say 1.4x as thats what the adapter claims) essentially you're adding a whole stop of light over a given area. and that 35mm F2.0 becomes a 24mm F1.4 on an APS-C with a speed booster.
MightyMike
Forum Pro
nothing wrong with waiting however those who have dabbled in creating such things and have studied the idea don't need a review to convince us of what we know is possible.
Michael de Ruijter
Leading Member
Rod Herdman
Veteran Member
I really really wanted one of these when I got my first APS-C dslr, so I could use FF lenses without thinking about the 'crop factor'.
Of course I couldn't get one then (and since I have a mirror in the way I guess I still cant).
But, since then, I have got over this crop factor business and just got used to using my FF lenses by considering 35mm as my standard lens. I know if I take a film shot in 50mm I use 35mm on APS-C. I know if I use 28mm on film I use 18mm on APS-C. For tele shots I don't really care anymore.
As a mirror DSLR user the only thing this would do for me is give me an APS-C equivalent of an 18mm FF lens (i.e. a 12mm lens). But, if i really wanted a 12mm lens I could go buy one, as other replies have said.
One stop increase in light ? High ISO capabilities of sensors and shake reduction have gone much further in improving low light IQ than this.
Yes it's a nice idea and I can see the advantages in some situations but I think people who are using an APS-C dslr won't really look at this.
I also do have a 'fit-on-the-lens' wide adapter if I'm really desperate which cost 1/10th of this adapter. Yes the quality isn't the best but it does if I'm desperate.
This is just my 2c of course, not a criticism of the product by any means. If there's a market, they'll sell.
Thanks for posting Meuh, an interesting read whatever you're opinion. Cheers,
Rod
Of course I couldn't get one then (and since I have a mirror in the way I guess I still cant).
But, since then, I have got over this crop factor business and just got used to using my FF lenses by considering 35mm as my standard lens. I know if I take a film shot in 50mm I use 35mm on APS-C. I know if I use 28mm on film I use 18mm on APS-C. For tele shots I don't really care anymore.
As a mirror DSLR user the only thing this would do for me is give me an APS-C equivalent of an 18mm FF lens (i.e. a 12mm lens). But, if i really wanted a 12mm lens I could go buy one, as other replies have said.
One stop increase in light ? High ISO capabilities of sensors and shake reduction have gone much further in improving low light IQ than this.
Yes it's a nice idea and I can see the advantages in some situations but I think people who are using an APS-C dslr won't really look at this.
I also do have a 'fit-on-the-lens' wide adapter if I'm really desperate which cost 1/10th of this adapter. Yes the quality isn't the best but it does if I'm desperate.
This is just my 2c of course, not a criticism of the product by any means. If there's a market, they'll sell.
Thanks for posting Meuh, an interesting read whatever you're opinion. Cheers,
Rod
Tan68
Veteran Member
kinda like the light emitted by a maglight covers a certain area.. then you zoom in with the maglite reflector zoom ring and the circle of light decreases in size.. but there is still the same amount of lumen going in that direction. so it gets a bit brighter
perhaps?
perhaps?
Michael de Ruijter
Leading Member
Yes. Same amount of light over a smaller area = brighter area.
Russell Evans
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This is gain applied to the sensor data. Camera manufacturers set the ISO range on a camera and there really isn't a standard scale; we know this from DXOMark. A f2 lens is a f2 lens, but that doesn't mean the gain applied to the sensor data is the same in a APS-C camera and a FF camera. The only way to reset the APS-C ISO range, or effect the gain applied, outside of the manufacturer doing it, is to report the aperture of the lens incorrectly to the camera. That doesn't change a f2 lens into a f1.4.
I guess I didn't understand how you were using "brightness"? There is more light hitting the sensor as light that would normally fall outside the APS-C sensor area is being concentrated on the sensor now and the scale the sensor uses to determine the gain needed on the sensor data needs to be adjusted. "Brigthness" as used to say a lens has a larger aperture, isn't correct, which comes to the DOF confusion, at least for me.
I think people are thinking a f2 lens that is reporting f1.4, is giving f1.4 DOF as well, but it again depends on what scale you are using since we have a APS-C scale for DOF and we have a FF DOF scale. People seem to be slipping into the FF scale in posting as the lenses are FF and thus thinking f1.4 FF DOF. There is a stop of difference in the APS-C scale and the FF scale, right? So if people are talking about the DOF using the APS-C scale, then the practical output is like a f1.4 lens. If people are talking about the DOF using the FF scale, a f2 lens is a f2 lens.
You're only considering the current lenses. There is such an array of older lenses to put into the equation as well.
The issue with FF has always been that the market is too small for a small player like Pentax. With something like this for a mirrorless k-mount APS-C camera, you now have a larger market for new Pentax FF lenses to be sold to and thus spread out the R&D costs across two market seqments. It seems like it could be a very good strategic move in K-mount to me.
Thank you
Russell
Russell Evans
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Sure. I think I was reading "brightness" in a different way, more as it has been used in the past as aperture. I probably am also looking at it a little differently as well as a change in the scale in the gain applied to the output. Aperture is a physical measurement or definition, so to me is seems wrong to use nomenclature that perverts the meaning. That's my point I guess, although I can't really come up with a better way to talk about it. It just seems from reading a lot of different posts, that people are switching back and forth, even in the same post, when talking about aperture or DOF and making the adapter sound like it is doing a lot more than it is.
Thank you
Russell
MightyMike
Forum Pro
its doing the opposite of a 1.4x TC so all the negatives of the 1.4x become positives of the 0.71x.
Wrong. All camera companies use a standard definition of ISO based on exposure (shutter speed + plus F-stop). Here is a quote from Andy Westlake
>"In the simplest fashion, according to SOS if you point the camera at a grey card, meter and shoot it should be rendered as middle-grey (50% luminosity). This makes sense - it's the way most photographers think about exposure.
>DxO's method is based on something different - highlight clipping. This is useful for comparing raw sensor performance but doesn't reflect how cameras will render the image. Expose cameras from various manufacturers based on DxO's measured ISO and they'll all clip whites at the same point, but give images of different brightness.
>"The difference between DxO's measured ISO and the manufacturer's recommended ISO gives an indication of what we call the highlight dynamic range of the camera. Ironically, the greater the difference (i.e. the lower DxO's ISO relative to the indicated), the larger the highlight dynamic range, resulting in smoother rendition and rolloff of highlight detail.
If you want to see the correct "measured" ISO, you should check DPReview who use a calibrated light meter to measure ISO (almost all cameras are similar).
Here is another proof that Dxomark's "measured" ISO doesn't tell you anything about shutter speed and F-stop in real usage (and their definition is not standard anyway to start with).
See Fuji X100
Now if we were to believe dxomark, X100 users won't see a change in shutter speed from ISO 1600 to ISO 6400!
Of course we know that is not true, and the camera behaves normally in real life. Here is X100's F-Stop and Shutter speeds in imaging resources studio
ISO 1600 - F8 - 1/250
ISO 3200- F8 - 1/500
ISO 6400 - F8 - 1 / 1000
Whatever happens under the hood is totally hidden to users. The camera behaves normally as far the user is concerned, and there is nothing wrong with X100's "ISOs".
The point is that if you want to see Nex-7 and 5D Mark III "measured" ISO (they way photographers understand ISO, you should check DPReview (not Dxomark).
Here is Nex-7 on DPReview
"we simply compare the exposure for each shot to the metered light level (using a calibrated Sekonic L-358), middle gray matched. We estimate the accuracy of these results to be +/- 1/6 EV (the margin of error given in the ISO specifications). We found that measured ISO from the Sony NEX-7 is roughly 1/3 stop higher than indicated across the ISO range - so ISO 100 indicated = ISO 125 measured."
Here is 5D Mark III
"In our tests we found that measured ISOs from the Canon EOS 5D Mark III match the marked ISOs within 1/6 stop accuracy, meaning ISO 100 indicated = ISO 100 measured."
If anything, you are going to see faster shutter speeds on Nex-7 at eqv ISO and F-Ssop (compared to 5D Mark III)!
But usually ((if you read DPreview), you should know that most cameras are within range of the calibrated light meter that DPR use. No cheating there by any camera company ...
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Silly statement, although with some sense.
I think the Speed Booster is a good idea - although I'm not interested in it - solving some practical problems but not something to be really excited nor a revolution.
If somebody could make a 0,2X converter for Pentax Q/Q10 - think of a 50 mm FA becoming f0,28 or the 60-250 becoming f0.8 - someone will say: "Do we need APS-C"?
Then somebody else will make a 0.12X adapter (I know, it's SF) for the iPhone - so you'll have a 50 f0.18 and a 60-250 f0.5 - and another guy will say: "Do we need Pentax Q?".
It's not that easy. Take a K5 and a Nikon D800. Pixel size is roughly the same. Put a 50 mm f1.4 in front of them. The 16 Mp Pentax image is similar to a 1,5X crop of the 36 Mp Nikon.
Now, use the Speed Booster with the K5. You have now a 33 mm f0.93 and an image with the same angle of view of the Nikon, only 1,5 times smaller. But the 1,5X crop of the Nikon uses 16 Mp, while the K5 with adapter only 7 Mp. So the winner is the Nikon.
Some can argue that you can make a K5III APS-C with 36 Mp. Yes, but it will have roughly 1,5x1,5=2,25 less ISO sensitivity, balancing the 2,25 "boost". And I'm sure that a 50 mm without a converter is better than a "converted" one. Yes, there is the chance that some aberration will be corrected, but others will sum, outweighing the casual enhancement. Same concept of digiscoping, where you use 2 unnecessary optical systems (when you could use a Q w/o lens!): you're lucky if you get decent results anyway.
So I think Eric (Viking79) is right when he says: "My guess is the adapter will work well with a few lenses and settings, but not all".
Yes, there is also some sense in the idea "Do we need FF?" To get high IQ, basically you need big lenses in terms of effective aperture. Then (in theory) you can have high focal length, low aperture and low resolution (in lines/mm, lpi etc.) for FF; or shorter FL, higher aperture and res for lower formats. All at a similar production cost. That's not happening with FF and APS-C for commercial and practical reasons. If you share the same (or similar) lens, the winner is clearly FF.
It's happening with high level compact cameras. Panasonic LX7 and Samsung EX2F both adopt a 24 mm eq. f 1.4 lens. Their effective max aperture is 3.5-3.6 mm (like a 16 mm f 4.5-4.7), very close to the 4 mm you get with the DA 16-45 at f4.
But the small sensor with 600 pixel/mm gives a diffraction limit around f2.8, so you need excellent sharpness. And you get that with a wealth of ED and aspherical lenses rarely seen in very expensive DSLR lenses. While a similarly priced low level DSLR with a kit zoom is not that better in terms of IQ.
So the trend will be towards big ultrasharp ultra luminous lenses coupled with very small cameras? Something weird-looking like the first weird Sony Nex with kit lens (huge tube on a cigarette pack) or the Q10 with K lenses on? Don't know, but it's possible.
Alberto
That's a big IF. A converter that can shrink FF image circle to Pentax Q size will be too big/expensive, and most likely impossible.
See above.
That claim makes no sense. No, you still have 16 MP of K-5, but you are capturing all of the light from the lens, instead of wasting some of the light that fell outside of APSC sensor before the adapter. That's why you gained one extra stop and kept the same angle of view.
It's not the same thing. The 36 MP APSC will have smaller pixels. It will not capture more (or less) light from FF lens. The speedboster allows the APSC sensor to capture all of the light from FF lens (same amount as FF sensor).
No, he is wrong.
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The change to APS costs
Sell 15mm wide angle which didn't work well with digital $700
Buy 16-40mm $400.
Works for all three bodies no adaptors, no loss of functionality.
500mm lens now 750mm equivalent.
Made adaptor for Visoflex lenses from existing parts no cost.
Why would a Pentax user need one?
Sell 15mm wide angle which didn't work well with digital $700
Buy 16-40mm $400.
Works for all three bodies no adaptors, no loss of functionality.
500mm lens now 750mm equivalent.
Made adaptor for Visoflex lenses from existing parts no cost.
Why would a Pentax user need one?
Gerry Winterbourne
Forum Pro
"I tcan't be done for FF lenses on the K-01". ET has said several times in this thread that it's impossible but repetition doesn't turn wrong into right. Every SLR lens shorter that about 40-50mm naturally focuses in front of the image (film or sensor) plane and needs a retrofocus group to pull it back. Different makes have different flange distances but all manage to get 35mm (say) FL lenses to focus. Optical adapters are already available for Nikon (say) bodies to take lenses from shorter-flange mounts.
It's clear, therefore, that it would be feasible to design a version of this adapter that would include some retrofocus capability to allow for the small projection it would need in front of the body.
"Improved IQ part 1". Steeve says that every piece of glass in the optical train degrades IQ; a few others have said that it's possible for extra glass to improve IQ. There isn't actually a contradiction between these two statements. All of the lenses we use have multiple elements because there's no single piece of glass that can give sharp images across a frame with no aberrations or distortions.
It takes several pieces of glass with different characteristics, each counteracting the adverse effects of the others, to get decent IQ. Different lenses have different characters because different compromises are made in their designs. Usually the design considers all of the elements working together but it's conceivable that once the optimum IQ (by whatever standards - resolution, flat field or whatever - the designer chose) a single extra element might improve every aspect of IQ across the board.
On the whole, though, I think it's more likely that any improvement in one aspect of the design will be offset by a reduction in one or more others. I think Steeve's idea that in practice there will be loss of IQ is most likely true, with the possibility that there might be a few exceptions where IQ improves.
"Improved IQ part 2". The link claims improved IQ but doesn't go into detail. As I read it, things like resolution in l/mm improve. This seems quite logical, because the lens's natural resolution is being compressed into a smaller space; ditto aberrations. But then we hit the fact that the smaller sensor needs more magnification for the same output picture size.
Improve l/mm by 1.5X and then enlarge by an extra 1.5X and you're back where you started - except that you've go the likely overall degradation that I discussed in part 1.
"DOF". I think the same argument applies here. The way a lenses gives tighter or wider DOF is determined by its optics and what it projects onto. Compress that by 1.5X and then enlarge it by 1.5X and you are back where you started.
This is actually just the same as the normal situation with different print sizes: DOF calculations are based on defined "typical" viewing conditions. Equalise the conditions and shooting parameters and you get the same DOF.
"Faster speed". Yes, if you concentrate a given amount of light - the amount entering the front of the lens - onto a smaller area it looks, and is, brighter. So you can use lower ISO. So far, so good, because lower ISO means less noise; but then magnify the image by 1.5X to get the same picture size and you magnify noise. Hmmm ...
Conclusion. The device obviously works. For ordinary print or screen seizes it gives good results. But I think some of the claims made for it are illusory.
It's clear, therefore, that it would be feasible to design a version of this adapter that would include some retrofocus capability to allow for the small projection it would need in front of the body.
"Improved IQ part 1". Steeve says that every piece of glass in the optical train degrades IQ; a few others have said that it's possible for extra glass to improve IQ. There isn't actually a contradiction between these two statements. All of the lenses we use have multiple elements because there's no single piece of glass that can give sharp images across a frame with no aberrations or distortions.
It takes several pieces of glass with different characteristics, each counteracting the adverse effects of the others, to get decent IQ. Different lenses have different characters because different compromises are made in their designs. Usually the design considers all of the elements working together but it's conceivable that once the optimum IQ (by whatever standards - resolution, flat field or whatever - the designer chose) a single extra element might improve every aspect of IQ across the board.
On the whole, though, I think it's more likely that any improvement in one aspect of the design will be offset by a reduction in one or more others. I think Steeve's idea that in practice there will be loss of IQ is most likely true, with the possibility that there might be a few exceptions where IQ improves.
"Improved IQ part 2". The link claims improved IQ but doesn't go into detail. As I read it, things like resolution in l/mm improve. This seems quite logical, because the lens's natural resolution is being compressed into a smaller space; ditto aberrations. But then we hit the fact that the smaller sensor needs more magnification for the same output picture size.
Improve l/mm by 1.5X and then enlarge by an extra 1.5X and you're back where you started - except that you've go the likely overall degradation that I discussed in part 1.
"DOF". I think the same argument applies here. The way a lenses gives tighter or wider DOF is determined by its optics and what it projects onto. Compress that by 1.5X and then enlarge it by 1.5X and you are back where you started.
This is actually just the same as the normal situation with different print sizes: DOF calculations are based on defined "typical" viewing conditions. Equalise the conditions and shooting parameters and you get the same DOF.
"Faster speed". Yes, if you concentrate a given amount of light - the amount entering the front of the lens - onto a smaller area it looks, and is, brighter. So you can use lower ISO. So far, so good, because lower ISO means less noise; but then magnify the image by 1.5X to get the same picture size and you magnify noise. Hmmm ...
Conclusion. The device obviously works. For ordinary print or screen seizes it gives good results. But I think some of the claims made for it are illusory.
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This doesn't address my point that a universal speedbooster adapter that can be used with all Pentax full frame lenses can't be made with the K-mount mirrorless body. The flange distance needs to be smaller. The adapter adds thickness, which will make the flange distance larger than the K-mount specification. Cameras with smaller native flange are more flexible with adapters. No question about that.
Come back when you have one. The people who made the adapter claim this is possible due to new cameras with smaller flange.
We have to wait and see actual images. Hopefully DPR will post a review with studio images. All we know now is that the paper claims the image quality is improved.
Nonsense.
Actual test images (by EOSHD) show that the DOF is identical to full-frame camera. He tested 5D Mark III and Nex-7 side by side and DOF was identical. We obviously need more info and actual images
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