gdanmitchell
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 Re: fuji medium format compared to others | |
Steve Spencer wrote:
gdanmitchell wrote:
Steve Spencer wrote:
gdanmitchell wrote:
Wow. A whole thread of posts saying much of what I''ve been saying about miniMF for most (but not all) photographers for the past few years.
The format offers some potential objective improvements for a certain small set of photographers, but they come at a cast in performance and lens options, and the IQ differences are only going to be significant if your output is of a certain sort.
And this post is a great example of something else you often discuss: confirmation bias. You see what you expect to see.
I fail to see what evidence there is of confirmation bias in my post. Are you sure you understand what the term means?
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quote]highdesertmesa wrote:
gdanmitchell wrote:
Wow. A whole thread of posts saying much of what I''ve been saying about miniMF for most (but not all) photographers for the past few years.
The format offers some potential objective improvements for a certain small set of photographers, but they come at a cast in performance and lens options, and the IQ differences are only going to be significant if your output is of a certain sort.
In all fairness, when you first started saying this in 2017, the only competition to the GFX 50S was the lower dynamic range 5DsR. It's a different full frame and APS-C environment today.
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True to some extent. But the GFX of that period was also rather different. I recall extensively testing one of those early 50MP gfx bodies against the 5DsR and doing a public A/B/x test with images from both at a range of sizes. Viewers’ ability to distinguish which they preferred didn’t rise above random until we got to about 30”x 40” where the percentage of people whose choice leaned toward GFX began to be slightly above 50%.
Again, the point isn’t that AOS-C or FF can equal the performance of miniMF, but that the differences are not noticeable until we get to some edge cases… which seems to be the general sentiment in this thread.
Dan I trust you understand that failing to see the evidence of confirmation bias is typical with confirmation bias. I trust you may even know about some of the studies that first demonstrated confirmation bias. A study by Darly & Gross (1980) is generally regarded as the first to demonstrate of confirmation bias. In that study they had Princeton students evaluate a young girl named Hannah's performance on a math and a reading test. In the video that depicted the test they saw Hannah get picked up by for the study at her house and that house was either a mansion or a trailer park. Hannah was in fifth grade and when they ended the video before watching her take the test it didn't matter whether she was rich (was picked up at a mansion) or poor (picked up at a trailer park). They thought she was probably about at a fifth grade level in math and reading. When they saw the same video or Hannah taking the test (and her performance had both some really good answers and some really bad answers), they judged her school ability very differently thinking she was reading at the sixth grade level and doing math above the fifth grade level when she was rich and that she war reading at the fourth grade level and doing math even lower when she was poor. They saw what they expected to see in her performance. None of the students evaluating Hannah thought they were being biased by the preconceptions about wealth and academic performance.
Your response reminded me of this study. You have argued for a long time that the GF system doesn't add that much and may not be worth it for a lot of photographers. That is your preconception, like the idea that wealthy kids are smarter in the study. I think the thread was a lot like Hannah's performance. There certainly were people arguing for your point of view, but there were people arguing for the utility of the GF system as well. Both sides were argued, just like Hannah doing really well on some questions and really badly on others. You perceived, however, that everyone was arguing what you believed before the thread just like the students saw Hannah as smart when she was rich and pretty dense when she was poor. You think that you are just reflecting what was in the thread, just like the students thought they were just basing their judgments on her performance on the test. It seems to me a pretty classic example of confirmation bias.
I know exactly what confirmation bias is and how difficult it is to fight. We all contend with it to some extent, and that’s why things like peer review are critical in the academic world, for example.
But holding a position is not the same as exhibiting confirmation bias.
In fact, the experiment I did with print files from FF and miniMF systems several years back was designed specifically to avoid confirmation bias. It was what is sometimes called an ABX test, in which observers who are not told the objective of the test nor the sources of the samples to compare are asked to compare three samples A, B, and X. A and B come from different sources, and X comes from either A or B, but is not identified as such.
Observers are asked to note differences they observe between A and B and to express a preference for one or the other. Then they are asked whether sample X is from the same source as either A or B. As you can probably anticipate, their ability to correctly answer that second question tends to cancel out potential confirmation bias in their answer to the first A/B question.
In my test, participants were provided with three image samples — in some cases in the form of prints, in. other (online) cases in the form of print files that they could print themselves. The samples came from a 50MP 5DsR and a 50MP GFX50S, both with roughly equivalent native lenses. The test images were shot with the systems on tripods and with all available procedures to ensure stability and accurate focus.
Then the images were prepared for printing in usual ways, at a range of sizes from (IIRC) 12 x 18 (or a f 4:3 equivalent, I’d have to look it up again) up to 40” x 60”. Then equal sized crops were produced from each of the full size images, in sizes that could be printed on letter-sized stock.
I was interested in seeing at what print size observers, as a group, could reliably express a preference for one source (A or B) over the other, with reliability determined in part by their ability to accurately determine whether X matched A or B. In the end, if memory serves, it wasn’t until we got to the 40” x 60” sourced images that the percentage choosing the sample from the miniMF image began to be higher than random probability.
So, yes, I understand what confirmation bias is, how susceptible we all (including you) are to its effects, and how we can try to see past it.
And, again, your point about this bias was also essentially irrelevant to the post your replied to.
I had a funny revelation the other day while thinking about some of my interactions with you on FM. I am, admittedly, a bit (I can see the eye rolls) a “bit” pedantic about some things here. And, yes, my posts can be pretty long and may require more than a cursory scan to understand.
The revelation was that you might be one of the “select group”here who can compete with and even exceed on occasion my level of what some will describe as pedantry… ;-)
Congratulations.
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