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Question of the Day: Which compact crossover would you choose?
Nikon tax?
- Thread starter bwana
- Start date
Who said you made a mistake?
Progenix Oj101
Dealer
Remind me then cause I can't find it. Mirrorless setup for shooting 400mm f/2.8 at 14 FPS with great high ISO performance (that Olympus EM-1 has a similar ISO score to the 600D, I'll be looking for at least four times that so two stops better high ISO performance please) so I can freeze motion and gets at least 1,000 shots from a single battery charge?
That's perfectly valid, but does not make DSLRs dinosaurs.
Pixual
Expert Member
Scores? Performance? Battery?
I take photographs. I am not flying a *****ing spaceship to Venus! You just don't get it. But carry on playing with your DxO scores and all that malarkey. Enjoy it if it gives you a boner. I'm off to make photos that neither you or anyone else will be able to discern what equipment they were taken from.
Not sure who you are replying to here, but I never said your move was a mistake.
DxO measurements were provided to back up a claim. I claimed that f/1.8 at m4/3 @ ISO200 gives the same DOF as 36x24 at f/4 @ ISO800, while providing the same amount of noise. Dismissing this as "measurebating" is rather rude, I think.
(Not that I am endorsing DxO "scores" --- but their individual measurements are above suspicion. You can perform the SNR experiment at home if you have an 18% gray card).
Why did I choose to reply to your post? Well, your post claimed that the Sigma Art 35 f/1.4 wide open produced worse results than what you obtained with your Oly 17 f/1.8 wide open. This claim is incorrect on several levels. Let us say you are printing an A4 photo from both systems. I note your objections to same-output-size comparisons, but in reality this is the best way to compare across systems with different sensor sizes. Let us just say your client wants an A4 wedding album photo. Here are the details (Using Lenstip's resolution results):
1. scaling up the m4/3 sensor photo to A4 requires a magnification factor of 16.5x
2. scaling up the 36x24 mm sensor photo to A4 requires a magnification factor of 8.25x
3. The Oly 17 mm lens obtains a centre resolution of 51 lp/mm (which is a pretty good score) at f/1.8, and 42 lp/mm at the edge of the frame. When printing at A4 size, this becomes 3.09 lp/mm in the centre, and 2.54 lp/mm at the frame edge. The centre resolution is about half of what a person with 20/20 vision can discern at normal viewing distances with the unaided eye.
4. The Sigma 35 mm at f/1.4 obtains 39 lp/mm in the centre, and 29 lp/mm at the frame edge. Printing at A4 size then gives us 4.73 lp/mm and 3.52 lp/mm at the centre and edge, respectively. A person with 20/20 vision will easily notice that the Sigma's A4 photo is sharper than the Oly 17 mm A4 photo.
5. If we move the comparison to equal DOF (as this seems to be you major objection to the 36x24 mm systems), we compare the Sigma 35 mm at f/4. According to Lenstip measurements, this yields 47 lp/mm and 32 lp/mm in the centre and edge, respectively, which translates to 5.69 lp/mm and 3.89 lp/mm in the A4 print. In other words, the Sigma 35 mm on a 36x24 mm camera produces a sharper print at the edge of the frame than the m4/3 system does in the centre. Yes, we have to use ISO800 on the 36x24 mm system versus ISO200 on the m4/3 system to keep the shutter speed the same, but as I have already demonstrated the apparent noise will be virtually identical (in the printed A4 photo).
You can claim that you do not believe in not comparing systems at pixel level, but I have just demonstrated a realistic example (A4 wedding album) that proves conclusively that the 36x24 mm system can indeed produce a significantly better final product. Your claim that the m4/3 17 mm lens at f/1.8 gives better results than the 36x24 mm system (wide open at f/1.4 or stopped down to f/4 to match DOF) is not supported by the facts. I have tried to keep this discussion objective, but I am forced to point out that your subjective experience was biased by a conflation of resolution and DOF. When you correct for this misunderstanding (comparing systems at equal DOF), then it is clear that the larger formats still offer better performance.
We can debate without end as to whether this better performance is desirable or even necessary for most people. I would certainly expect a professional photographer to use the correct tool for the job.
Of course not. I am not going to bother showing the math here, but since the magnification factor of web images is much lower than that of the A4 case discussed above, it is reasonable to expect that the effective resolution of both systems will easily exceed the resolution limit of the human eye (which happens to be about 6.88 lp/mm at A4 size).
No argument there. You are welcome to use whatever system you prefer --- but going around dismissing larger format systems based on a misunderstanding, and then refusing to consider the objective evidence is not the way to convince people to try out modern mirrorless systems.
Progenix Oj101
Dealer
And once AGAIN you've dodged the question. If I need the specification I mentioned, which mirrorless setup should I go for? That's not needed for flying a spaceship to Venus, that would be for shooting high speed sports in bad lighting for a living.
I'll tell all the professional product, landscape and fashion photographers I can find to move away from their medium format Hasselblad, Pentax and PhaseOne systems (medium format is still DSLRs) to pick up a compact camera.
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aleksandar
Expert Member
Bad fvdbergh, spoiling argument with sensible data.
Just few side notes:
Reason why many years ago I selected canon was due to larger lens selection and price. Also take note that in SA canon second hand marked is much bigger. Otherwise for normal shooter there is not much difference.
About focusing and shallow DOF, do not rely on AF, install custom focusing screen and use MF. Works great for portraits and mainly static objects. Spray and pray does not work in this case.
There is no substitute for a fast lens and it is nice to know that you can shoot at f/1.2.
About different formats, well we are moving on and stuff is getting smaller and better but as pointed by both sides there are circumstances when we will not see difference and then there will be cases where difference will be visible. Question is what is good enough and that largely depends on shooter and audience.
So is this P*** contest done and can we tell all the people that canon is way to go ;-)
Just few side notes:
Reason why many years ago I selected canon was due to larger lens selection and price. Also take note that in SA canon second hand marked is much bigger. Otherwise for normal shooter there is not much difference.
About focusing and shallow DOF, do not rely on AF, install custom focusing screen and use MF. Works great for portraits and mainly static objects. Spray and pray does not work in this case.
There is no substitute for a fast lens and it is nice to know that you can shoot at f/1.2.
About different formats, well we are moving on and stuff is getting smaller and better but as pointed by both sides there are circumstances when we will not see difference and then there will be cases where difference will be visible. Question is what is good enough and that largely depends on shooter and audience.
So is this P*** contest done and can we tell all the people that canon is way to go ;-)
I aim to please
Excellent point about the custom focusing screen. Not 100% sure about full frame bodies, but to my knowledge the APS-C cameras actually have a Fresnel lens built into the focusing screen. This increases the apparent brightness of the focusing screen, but this focusing screen Fresnel lens has an aperture of f/2.8. The implication is that focusing errors on a f/1.4 lens will be evaluated at f/2.8 through the viewfinder, leading to rather spotty manual focus accuracy.
You can verify this (as I should have done before this post, but it makes for a good story ...) quite easily on a body that has DOF preview. Pick a subject with sufficient detail (Lensalign target, or a newspaper viewed at an angle). Now look for visible differences in the DOF as you step from f/1.4 through to, say, f/4 (i.e., compare the image in the viewfinder with and without DOF preview). If this Fresnel lens theory holds, you will not see any differences between f/1.4, f/1.8 and so on, with visible DOF differences only showing after f/2.8.
To cross check, compare the photos captured at these apertures.
Progenix Oj101
Dealer
Or... Use live view. Goes all the way down to f/1.
Pixual
Expert Member
It's very easy to regurgitate scientific proclamations on the internet as the gospel when it comes to photography. Practical experience quite often shows that said proclamations of increased visual acuity are not actually repeatable in the field. This is my experience.
I do not care what DxO or any other scientifically based argument says: I base my arguments on real world field experience as a professional photographer.
If you shoot the Sigma Art 35/1.4 wide open it will not be as sharp as the Olympus 17/1.8 is wide open. Where I will concede something in this regard it is that human and machine error in the use of the Sigma (camera dependent) might factor in the ultimate sharpness of the output. For example, if you are shooting hand held the Olympus will always be sharper for two reasons: 1) the in-body-image-stabiliser of the OM-D cameras will compensate for your movement, and 2) the depth of field of a 17mm f/1.8 lens is greater than that of a 35mm f/1.4 lens. Something else that often comes into play is that the mirror slap of a DSLR most definitely does affect sharpness if you are not using a delayed shutter release or electronic first curtain.
The only time the Sigma might be sharper than the Olympus in the real world is if you are using it on a tripod with a super high res camera like the Nikon D810, which in my experience completely defeats the purpose of having a super fast lens in the first place.
So in a situation where you need a 35mm angle of view in low light conditions, which is the better option to have? The Olympus is hands down the winner, every single time. I base this on real work I have done with both lenses in very low light.
I do not care what DxO or any other scientifically based argument says: I base my arguments on real world field experience as a professional photographer.
If you shoot the Sigma Art 35/1.4 wide open it will not be as sharp as the Olympus 17/1.8 is wide open. Where I will concede something in this regard it is that human and machine error in the use of the Sigma (camera dependent) might factor in the ultimate sharpness of the output. For example, if you are shooting hand held the Olympus will always be sharper for two reasons: 1) the in-body-image-stabiliser of the OM-D cameras will compensate for your movement, and 2) the depth of field of a 17mm f/1.8 lens is greater than that of a 35mm f/1.4 lens. Something else that often comes into play is that the mirror slap of a DSLR most definitely does affect sharpness if you are not using a delayed shutter release or electronic first curtain.
The only time the Sigma might be sharper than the Olympus in the real world is if you are using it on a tripod with a super high res camera like the Nikon D810, which in my experience completely defeats the purpose of having a super fast lens in the first place.
So in a situation where you need a 35mm angle of view in low light conditions, which is the better option to have? The Olympus is hands down the winner, every single time. I base this on real work I have done with both lenses in very low light.
Not sure why you persist with the insults. I have replicated Lenstip's resolution measurements with my own lenses, using software I developed from first principles. If you have proof that these (e.g., Lenstip's resolution measurements) are defective in some way, I would like to see it.
Why do you reject the scientific method? It allows us to make repeatable measurements independently, so that when we start discussing things we know that we are talking about the same things.
There is no reason why "real world field experience" cannot be used to derive valid scientifically sound experimental results. It is, however, vital that the comparisons be performed in a fair way. For example, an f/1.8 lens on m4/3 is not equivalent to an f/1.8 lens on a 36x24 mm sensor when considering noise.
You will have to explain how you perform this sharpness comparison, because your claim contradicts objective evidence gathered using the accepted methods of sharpness measurement and comparison.
Indeed. IBIS is a great system, and with an EVF one of the disadvantages of IBIS is eliminated. But image stabilization on such a wide angle lens (35 mm focal length FOV) is not nearly as useful as it is on a 300 mm lens (I'd be happy to demonstrate this, but I trust you will agree on this). The only reason why Canon recently started introducing IS on wider primes is to aid video. Realistically, if you are in such low light that the combination of a large aperture lens and a high ISO capability requires IS to eliminate camera shake, then subject motion is going to be a much bigger problem.
We have been over this point before. Stopping down the f/1.4 lens to f/4 and bumping the ISO by two stops gets you to exactly the same DOF and image noise. If you cannot concede this point, then this discussion will never get anywhere.
Mirror slap only affects a narrow range of shutter speeds. The exact range depends on the camera in question. I know on my D7000 the mirror slap peaks somewhere between 1/15 and 1/60 s. Outside of this range it barely measurable, and definitely not something to be concerned with. Since subject motion is a significant problem in this shutter speed range anyway, I have no real loss of functionality.
Sorry, you will have to provide proof if you want to make such a strong (and frankly unbelievable) claim.
I have no doubt that you believe the outcome of your tests. The only way that you will convince me (or a large number of other forumites, it would seem) is if you describe the process by which you performed these real world tests.
Progenix Oj101
Dealer
DxOMark isn't the be-all and end-all of photography, but it does give directly comparable results that are completely objective and take all subjectivity out of the equation. It DOES have a use.
Pixual
Expert Member
-ignore previous comment-
I am a professional photographer who has used more cameras and lenses than you have probably ever held in your hands. Brands including Leica, Angenieux, Nikon, Canon, etc, etc.
I take photographs for people who pay me money to do that.
I know what works for me based on EXPERIENCE not some geek site where they take photos of newspapers and brick walls.
I have gotten better results with MFT than I have gotten with any other system. Period.
That's how I perform my tests.
I am a professional photographer who has used more cameras and lenses than you have probably ever held in your hands. Brands including Leica, Angenieux, Nikon, Canon, etc, etc.
I take photographs for people who pay me money to do that.
I know what works for me based on EXPERIENCE not some geek site where they take photos of newspapers and brick walls.
I have gotten better results with MFT than I have gotten with any other system. Period.
That's how I perform my tests.
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From what I've read many mirrorless cameras have vibration, the Olympus being one where it is a problem over a much wider range of shutter speeds. Their solution was to introduce a delay, something that can normally be done on DSLRs.
It was you who claimed that effectively DSLRs are useless, outdated, and people were stupid to buy them. Rather than that they had not worked well for you.
CAPS LOCK
Executive Member
You have an eye infection dude, relax..... YOU instigated this debate fueled with pepped-up anger - why all this emotion? Your subjective persistence taints your credibility... You were actually believable w.r.t to Mirrorless systems, you now simply off-putting, and whatever it is you trying to achieve is counter-productive by your endless diatribe of self importance..I'll take brickwalls to anecdotal evidence any day of the week..