I suspect he means F6 equiv, given he also lists the focal lengths as 24-120mm (which is not the focal length range of any Fujifilm zoom).
ie: 16-80mm F4.0 / 24-120mm F6.0 equiv.
Richard - DPReview.com
Last edited:
-
Welcome to the new forums! Please read this first. For known issues we are working to resolve, click here.
APS-C/MFT equivalent FF lenses
- Thread starter 4oliver2
- Start date
ie: 16-80mm F4.0 / 24-120mm F6.0 equiv.
Richard - DPReview.com
Many thanks for this detailed answer! While I think I understand most of it, a few questions remain.
Went back to re-read dpreviews noise primer part 2. Makes sense, but I'll do some more digging to (hopefully) really understand everything. I'm not sure if I yet properly understand how the second gain step interacts with either up- or downstream read noise differently, but maybe that's not that relevant, since from what I've understood, the second gain step generally reduces the impact of the read noise. So if the Z6III suffers from higher read noise, that's a proper explanation to what can be observed in the charts.
I was aware of the lower base ISO of the A9 III. If I've understood correctly, I should still be able to compare the cameras at the same ISO levels (that's what I've tried to express in my initial question).
The interesting thing is, that in the dynamic range chart of photonstophotos, the A9 III basically equals the A7 IV's dynamic range, as does the Z6III, after it's second gain step, and is only slightly trailing the A7 IV, even besting the Z6III at ISO 250. I do see however, that there seems to be some noise reduction (the "triangle down" symbol in the chart) which might skew the results. But still, according to this measurements, the A9 III performs visibly better than an APS-C camera in DR and only worse than the Z6III when the cameras are compared at their base ISOs.
Please excuse the extensive use of photonstophotos for making my point, this just happens to be such an easily accessible tool for objective comparisons. I'm not attempting to invalidate observations by you or dpreview, I'm just using the low hanging tools at my disposal.
But I guess, if I understand correctly (after writing all the stuff above, not willing to delete it anymore), your main point is that DR does not tell you where the noise is more prominent. So even if the A9III equals the Z6III's DR, it might show more noise in the more important tonal ranges.
For the third part of the noise series: I would definitely read it.
of course. without those assumptions, the whole discussion of equivalence doesn't make any senseI describe it as a potential advantage because, of course, it all depends on the f-stop and shutter speed one uses, how much total light is delivered to the sensor, and how much is removed from the image through cropping in post.Leaving the discussion of your actual observation aside (they are anyway ongoing in another branch of this thread) I think we can settle on something like "FF has an advantage of >= what equivalence tells us over APS-C" here.Forget about the theory. before Christmas i shot a formal couple. my a7iv with a 2.8 lens and my a6700 with a 1.4 lens, just to set the record straight. the a7iv walked all over the a6700 for IQ and lower noise. both cameras provided professional results and i sold images from both cameras as it was a 2 camera shoot so no lens changes. but dont kid yourself that smaller sensors can equal larger, and that includes macro. as for Richard's comment im still waiting for anyone to prove that MF can outperform FF at 10:1
again, of course
Not sure which ones you are referring to, but I would be surprised if I've missed them, assuming there are no lenses in Z mount which are not available as well in E mount (which I'm invested it) - native lenses aside of course (in my initial post, I'm trying to outline the zoom- and aperture-range I would be interested in. Haven't heard of any small third party 24-1xx zooms around)
In the abstract above the bullets, I write "Let's e.g. compare the Fujifilm XF 16-80mm 4.0 R OIS WR to the Canon Canon RF 24-105mm 4.0-7.1 in ff terms". With "in ff terms" I mean ff equivalency
Dual Conversion gain is a change in the pixel itself, so the reduction in noise (in exchange for a reduction in full well capacity) reduces the upstream read noise. But, as you say, what' matters is that it reduces read noise.
At ISO 250, the a9 III will perform much like any other full-frame camera. However, this higher base ISO is the cause of its lower peak DR AND lower peak IQ (it'll be comparable to the output of an APS-C camera at ISO 100, but will be significantly better if you use both at ISO 250).
But the higher base ISO is the reason for its lower peak DR. So it and the Z6III have comparable peak DR figures but for very different reasons, and the Z6III's base ISO images will look better than the a9IIIs.
The problem is that, while it's easily accessible, objective and very dependable (though using a cut-off of Bill's own invention, which makes it hard to compare), it's only showing one very specific aspect of IQ. As the Z6III and a9 III show, two cameras can have the same peak DR number for very different reasons.
Likewise I used to see a lot of people quote Bill or DxO's numbers for peak DR of the Canon EOS 6D and Olympus E-M1 and conclude that they had the same image quality, which isn't the case at all.
DR numbers can be interesting, but they can be a little bit like grabbing the tail of an animal while blindfolded: you risk making some distinctly spurious assumptions about what the animal is.
This three-parter isn't my best (I rushed to put it out when I thought we were closing), but it tries to convey what DR does and doesn't tell you.
All DR tells you is when noise (be that read noise or shot noise from lack of light) exceeds a specific threshold in the extreme dark shadows below what's typically used in a standard image. Two cameras with the same DR cut-off can have radically different tonal quality above that, depending on the cause.
Richard - DPReview.com
A74Me
Senior Member
- Messages
- 3,246
- Reaction score
- 2,246
not pushed in post ,i like to get my exposure close in camera, just saves me alot of time and money. im not real good at PP raw files with good exposure. i never bother with NR in post ever.Thanks for confirming that.no flash, i did have a trigger on top of the a74 but didnt take the off camera strobe in the gym. this is in a gymnasium the photos are groups of kids, which is why i cant show you the whole image just the background noise performance.It looks like the flash was on on the FF camera and off on the APS-C.both good images colour wise but when zoomed in to view noise levels and detail i was surprised how much cleaner the a7iv image was. the a6700 is the closest apsc sensor to FF i have seen, and dont hesitate shooting the 2 cameras side by side at an event or in my studio, now i know that the a6700 can be backed up instantly via usbc while shooting makes for a very good studio camera as well when i have twin studio set ups.
i actually have the drive with me i will post some head shot comparisons later
Following your example I did what I've never done before - looked at my images at 300% magnification, specifically, shadows in SOOC JPEGs at different ISOs. Despite having Noise Reduction dialled to minimum and having the default Sharpening setting (Fuji, APS-C, 24Mpx and 26Mpx sensors), I get to the same level of noise as seen in your images at about ISO 1600 - ISO 3200. My raw conversions are cleaner than SOOC JPEGs, as they should be.
This is also the case with the DP comparison tool for Sony A6700. Your ISO 320 shots look far too noisy. Something is amiss. Were the raw files pushed in post processing by a few stops?
A74Me
Senior Member
- Messages
- 3,246
- Reaction score
- 2,246
totally agree, tonal quality is what i look for in a camera, I was presently surprised how good the a6700 stacked up to my a7iv. if you look at numbers then you would think my old a6300 had equal/ slightly better IQ than the a6700 buts thats far from the truth in reality.
You might be surprised. A lot of photographers haven't made the connection between the amount of light energy used to make a photo and the quality of the resulting image. It comes from, candidly, a surplus of misinformation that's commonly presented or taught as gospel. As a result, it's not uncommon for some photographers to see the larger format as being inherently superior regardless of the settings, exposure and total light energy used to make photos.of course. without those assumptions, the whole discussion of equivalence doesn't make any senseI describe it as a potential advantage because, of course, it all depends on the f-stop and shutter speed one uses, how much total light is delivered to the sensor, and how much is removed from the image through cropping in post.Leaving the discussion of your actual observation aside (they are anyway ongoing in another branch of this thread) I think we can settle on something like "FF has an advantage of >= what equivalence tells us over APS-C" here.Forget about the theory. before Christmas i shot a formal couple. my a7iv with a 2.8 lens and my a6700 with a 1.4 lens, just to set the record straight. the a7iv walked all over the a6700 for IQ and lower noise. both cameras provided professional results and i sold images from both cameras as it was a 2 camera shoot so no lens changes. but dont kid yourself that smaller sensors can equal larger, and that includes macro. as for Richard's comment im still waiting for anyone to prove that MF can outperform FF at 10:1
It never hurts to remind folks that any image quality advantage a larger format system may have over a smaller format is dependent upon the light energy used to make the photos.
It's why micro four thirds, APS-C and full frame all have populations of dedicated users. With any of the above, great publishable award-winning images can be made...even if they don't match the dynamic range and image quality potential of medium format.
Sorry, I forgot you're in E-mount. I did a search in the B&H inventory for third-party lenses for (this time) E-mount, designed for full frame with maximum apertures of f/4.5 to f/8. You may be familiar with them, already. I can't speak to the build or image quality of any on the list. That said, there may be one or two you'll find of interest. Here's a link: E-mount primes at B&H
--
Bill Ferris Photography
Flagstaff, AZ
Last edited:
At the same exposure, the full frame camera collects more light, has less noise, and greater dynamic range.
A74Me
Senior Member
- Messages
- 3,246
- Reaction score
- 2,246
6 years ago i used to fight tooth and nail for the m43 system, as i shot professionally with it for 5 years. and started shooting extreme macro with a em5mk2 and then an em1mk2 using a 4x objective. i thought it was the bees knees and i was shooting great images of live subjects and slowly designing new ways to shoot live, the forums all accepted that the smaller sensor could place more pixels on the subject with greater DOF and greater magnification. since buying the a7r2 and experimenting i started to shoot extreme macro that no one had ever tried before with results that were far superior to anything id shot before, what i discovered is diffraction with smaller pixels associated with noise(stacked) degraded images shot at 10x and then researched that 5 micron pixels are the smallest sized pixels to require diffraction free and noise free images (comes a7iv). to shoot 20x and you need pixels up to 10+ micron and 10 megapixel sensor which only specialized microscopes use. equivalence as i knew it went out the door because no one had actually experimented with larger sensors for large magnification images. you keep hearing that no one views images at 100% buts that is exactly what i want people to do with my images, they were designed and taken to be viewed at 100 to 200 % as then you enter a world no has seen before and the bugs are live and running around it can take up to 36 hours to complete a shoot with up to 400 images stacked.You might be surprised. A lot of photographers haven't made the connection between the amount of light energy used to make a photo and the quality of the resulting image. It comes from, candidly, a surplus of misinformation that's commonly presented or taught as gospel. As a result, it's not uncommon for some photographers to see the larger format as being inherently superior regardless of the settings, exposure and total light energy used to make photos.of course. without those assumptions, the whole discussion of equivalence doesn't make any senseI describe it as a potential advantage because, of course, it all depends on the f-stop and shutter speed one uses, how much total light is delivered to the sensor, and how much is removed from the image through cropping in post.Leaving the discussion of your actual observation aside (they are anyway ongoing in another branch of this thread) I think we can settle on something like "FF has an advantage of >= what equivalence tells us over APS-C" here.Forget about the theory. before Christmas i shot a formal couple. my a7iv with a 2.8 lens and my a6700 with a 1.4 lens, just to set the record straight. the a7iv walked all over the a6700 for IQ and lower noise. both cameras provided professional results and i sold images from both cameras as it was a 2 camera shoot so no lens changes. but dont kid yourself that smaller sensors can equal larger, and that includes macro. as for Richard's comment im still waiting for anyone to prove that MF can outperform FF at 10:1
It never hurts to remind folks that any image quality advantage a larger format system may have over a smaller format is dependent upon the light energy used to make the photos.
It's why micro four thirds, APS-C and full frame all have populations of dedicated users. With any of the above, great publishable award-winning images can be made...even if they don't match the dynamic range and image quality potential of medium format
A74Me
Senior Member
- Messages
- 3,246
- Reaction score
- 2,246
short answer, if my a7iv suddenly died, i would not hesitate in just shooting the a6700 for my pro work. great little compact camera matched to the 18 135 for a fun walk around kit, stick the raynox 250 on the front and take high quality macro as well.Leaving the discussion of your actual observation aside (they are anyway ongoing in another branch of this thread) I think we can settle on something like "FF has an advantage of >= what equivalence tells us over APS-C" here.Forget about the theory. before Christmas i shot a formal couple. my a7iv with a 2.8 lens and my a6700 with a 1.4 lens, just to set the record straight. the a7iv walked all over the a6700 for IQ and lower noise. both cameras provided professional results and i sold images from both cameras as it was a 2 camera shoot so no lens changes. but dont kid yourself that smaller sensors can equal larger, and that includes macro. as for Richard's comment im still waiting for anyone to prove that MF can outperform FF at 10:1
Further, something which actually favors FF even more compared to more compact sensors: Given you can work at base ISO, a FF camera will give you better dynamic range compared to more compact sensors with equivalent lenses.
But ultimate image quality is not the motivation for this thread, like I already mentioned, I just want to be able to use my most competent and enjoyable camera in as many scenarios as possible. Still, since it's also kind of a technical discussion, I thought it should be mentioned somewhere.
Sure, because it's a larger sensor. But when you put a lens on a FF or DX sensor body, the physical size of the aperture does not change depending on which body its on, so the lens still lets the same amount of light in and the DX sensor just does not use all of it because the smaller surface area does not require the same amount of light as a FF sensor to fill. The difference in physical size of the aperture only affects dof and possibly bokeh.
Neither does the focal length, Bob, yet people keep saying that 35 mm on the APS-C is equivalent to 50 mm on full frame. Do you accept this?
per unit area
But since what matters for image quality is "all of the light", not the light per unit area, people use "equivalent f-number" that defines the total amount of light on the sensor, DOF and also diffraction blur. How convenient.
The equivalent f-number is just a number. A very useful number if you understand what it means. It doesn't describe the lens, it describe the image the lens produces on a specific sensor size.
Last edited:
That's what gives larger format systems the potential to make higher quality images; their greater light-gathering potential.
Correct.
Yes.
It's not a matter of how much light the sensor requires. When both systems are working with the same exposure, the smaller sensor is physically incapable of capturing the same total light energy as the larger sensor.
Not quite. The lens entrance pupil diameter (the size of the aperture) determines how much total light the lens collects from the subject. In addition to determining depth of field in the image formed by the lens, aperture determines the total light projected toward the sensor.
This is the central truth upon which equivalence works as a tool for determining the settings needed to make the same photo with different format systems. By definition, equivalent photos are made by systems working with different exposures (same shutter speed, different f-stop) but the same lens aperture; entrance pupil diameter.
--
Bill Ferris Photography
Flagstaff, AZ
Last edited:
This is false.
You could just as equally say: "Only if you care about the photographic impact of the results. If you like the values in your EXIF to be consistent, then FF of DX makes no difference."
It's well-established that equivalence is a 'whole-image' perspective and the traditional exposure model is a 'per unit area' perspective that's specifically designed to work across formats.
So it is senseless (and needlessly derailing) to say "but you could use the same exposure values," because yes, that's how the exposure system works (at the cost of disguising why you get images with different DoF, noise, tonal quality and diffraction when you match exposure values on different formats).
Saying it's just about DoF is false and (intentionally?) misleading.
The statement 16-80mm F4 on APS-C is equivalent to (a hypothetical) 24-120mm F6.0 lens used on FF is factually correct, its meaning is well understood and saying 'only in terms of DoF' is incorrect and profoundly unhelpful.
Richard - DPReview.com
Last edited:
chrisfisheye
Senior Member
- Messages
- 2,005
- Solutions
- 4
- Reaction score
- 1,403
Exactly.
My answer about this topic is that equivalence means equal value. Exposure has no value per see, instead people should refer to total light.
So when people that that is is only partially equivalent when we say that f/2.8=f/5.6 (between m43 and FF) ant that this is only about dof, they are wrong. It is fully equivalent because exposure is NOT part of equivalence.
Another thing that I would like to add, I know it will surprise many people here, but it is absolutely wrong to say that there is a debate about equivalence.
The proof ? Honestly there is a consensus in the scientific forum. Really.
So it is more like a debate between people saying that the earth is flat and people understanding it is not. Strangely the first people can continue to pretend it is flat and even receive many likes, depending on which forum you are in.
But to be honest and I am surprised, the tendency in these forums is that equivalence is better understood. I thought it would never happen.
The values listed in exif of my APS-C and FF sensor cameras list the aperture value as the same no matter which format I am using as set at lens, but the exif does list the focal length as concerns lens design "and" the 35mm equivalent focal length. Equivalence is great for us old devils that. shot 35mm for so many years to keep things in a relationship with what we have becomes engrained with. But for newer photographers, I see it becoming a maze of confusion in many realms. Kinda makes one wish we as a whole had never coined the phrase. Way back, we never discussed equivalence much when swapping back and forth between MF and 35mm or even 4x5. We just knew what lens focal length was used for what purpose on each format we used.
We also were aware of the different quality of the results obtained with different formats (not just the different DOF) seen when the film type was the same, the shutter speed was the same, and the f-number was the same ... although we didn't know equivalence was a way to explain those differences.
Last edited:
That's my point. Matching exposure values in the EXIF is the main thing you get in common if you use matched exposure values on two different systems.
And is the key concept here. A lens is one thing and can be equivalent to another. Both can be true.
Not helped by people spuriously saying it's about DoF.
There's nothing to stop one doing that now. But people did talk about magnification or enlargement when trying to explain the magnitude of difference in quality between formats. Equivalence is essentially the same thing.
Richard - DPReview.com
Similar threads
- Locked
Keyboard shortcuts
- f
- Forum