HubertChen

HubertChen

Lives in China Guangzhou, China
Works as a CEO
Joined on Jun 29, 2011

Comments

Total: 592, showing: 61 – 80
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On Sony Alpha A7 / A7R preview (2381 comments in total)

Sony 7 Cameras: Small, powerful and reasonably priced
Sony FE Lenses: Big, slow, expensive

I always use both: Camera + Lens. What is the point of a small camera with big lens? Seems Olympus, Fuji and Pentax have bigger camera bodies. But once lenses mounted to them, they have smaller and lower cost systems with faster lenses.

I am really impressed with the alpha 7 cameras. I applaud Sony. I worry the big, expensive and slow FE lenses will hamper the success.

Direct link | Posted on Oct 17, 2013 at 12:38 UTC as 369th comment | 12 replies
On Preview:canon-eos-70d (1333 comments in total)
In reply to:

HubertChen: There is a method to separate imagined quality differences from real quality differences: Double blind test: The test engineer does not know which sample he is showing / playing and the test person does not know. For each sample the judgment of the test person is recorded and later analyzed.

Have a large enough number of test persons, say 10, and you can clearly identify quality features that are recognizable. Say at least 8 out of 10 notice the higher quality.

As for harmonic distortions in audio, trained musicians can detect even minute distortions, regular people can't. So depending on who is the audience, low distortion is important or not.

Once a group of people start discussing relevance on a level where everybody seems to have a different opinion, it actually is becoming time to do double blind tests and see how in real life this quality difference can or cannot be recognized. Who continues talking at this point, loves to talk and actually does not care to find the truth.

My apologies for this post to show. I started writing my above posts based on this one which I posted elsewhere. By the time I was finished the post system had posted the original text. It did not allowed me to delete it, nor did it allowed me to post my final result with the error message something like this: "Your post can not be edit due to time out". If any dpreview admin is reading this, I suggest to change this behavior. I am not OK that a version of my text is published before I press the post button and then what I did not wanted to publish can not be deleted or edited. Such kind of behavior of your system makes me less motivated to use it.

Posted on Oct 13, 2013 at 03:54 UTC
On Preview:canon-eos-70d (1333 comments in total)
In reply to:

HubertChen: dpreview clearly formulated a question to which they wanted to find the answer: How does performance compare of the new AF system (Dual Pixel) versus the old AF system (View Finder PDAF).

I see dpreview to clearly express the test question, then design a series of tests to find the answer to the question. These tests are created in order of relevance and less important tests are left out to leave more time for the important tests. Then perform the tests with precision and analyze the results. Finally to back the findings of the lab with real world shooting.

dpreview earned my respect for doing an important job with integrity and accuracy.

I see many people in the forum to take the test results and formulate new questions, such as was the test procedure tuned to optimized precision of OVF PDAF? This simply is not meaningful.

The tests were not designed to answer these questions and as such the test results can not be used to be interpreted to find answer to these questions.

Yet a lot of discussions do just that. Such discussions are very harmful. They reduce motivation of dpreview to spend a lot of resources on thoroughly testing new technologies about fitness in real photography life.

Such discussions in this intensity also reduce motivation of the serious reader. In order to find meaningful posts, we have to wade through a huge amount of noise.

Make this Win-Win: It is obvious many posters here are interested in optimizing OVF PDAF precision with micro adjustments. Then why not create a forum thread and discuss it there. Keep information focused on topics to increase the Signal to Noise level for everybody.

Posted on Oct 13, 2013 at 03:49 UTC
On Preview:canon-eos-70d (1333 comments in total)

dpreview clearly formulated a question to which they wanted to find the answer: How does performance compare of the new AF system (Dual Pixel) versus the old AF system (View Finder PDAF).

I see dpreview to clearly express the test question, then design a series of tests to find the answer to the question. These tests are created in order of relevance and less important tests are left out to leave more time for the important tests. Then perform the tests with precision and analyze the results. Finally to back the findings of the lab with real world shooting.

dpreview earned my respect for doing an important job with integrity and accuracy.

Posted on Oct 13, 2013 at 03:46 UTC as 60th comment | 1 reply
On Preview:canon-eos-70d (1333 comments in total)

There is a method to separate imagined quality differences from real quality differences: Double blind test: The test engineer does not know which sample he is showing / playing and the test person does not know. For each sample the judgment of the test person is recorded and later analyzed.

Have a large enough number of test persons, say 10, and you can clearly identify quality features that are recognizable. Say at least 8 out of 10 notice the higher quality.

As for harmonic distortions in audio, trained musicians can detect even minute distortions, regular people can't. So depending on who is the audience, low distortion is important or not.

Once a group of people start discussing relevance on a level where everybody seems to have a different opinion, it actually is becoming time to do double blind tests and see how in real life this quality difference can or cannot be recognized. Who continues talking at this point, loves to talk and actually does not care to find the truth.

Posted on Oct 13, 2013 at 03:20 UTC as 61st comment | 1 reply
On Preview:canon-eos-70d (1333 comments in total)
In reply to:

jkokich: This reminds me of stereo systems in the 70's. There was all this hype about distortion levels you needed an oscilloscope to measure; the human ear couldn't detect the difference.

There is a method to separate imagined quality differences from real quality differences: Double blind test: The test engineer does not know which sample he is showing / playing and the test person does not know. For each sample the judgment of the test person is recorded and later analyzed.

Have a large enough number of test persons, say 10, and you can clearly identify quality features that are recognizable. Say at least 8 out of 10 notice the higher quality.

As for harmonic distortions in audio, trained musicians can detect even minute distortions, regular people can't. So depending on who is the audience, low distortion is important or not.

Once a group of people start discussing relevance on a level where everybody seems to have a different opinion, it actually is becoming time to do double blind tests and see how in real life this quality difference can or cannot be recognized. Who continues talking at this point, loves to talk and actually does not care to find the truth.

Posted on Oct 13, 2013 at 03:19 UTC
On Preview:canon-eos-70d (1333 comments in total)
In reply to:

crackshooter: As soon as I learned that the camera rememberes the micro-adjustment of AF from lense to lense, (thanks Erik Magnuson and Bob Meyer), then I really see no problem whatsoever. I am used to, and expect to tweak equipment when it is brand new, be it bicycles or a kayak...
-Regards from first time DSLR buyer.

@ R Butler: I fully agree! May I suggest a third question?

3) After you tune the Micro adjustment, how long will it remain accurate?

The Mirror mechanism is mainly made of plastics. Pretty much all plastics have a thermal expansion coefficient, and worse, they expand with increased humidity and shrink with low humidity. Plus the reflex mirror is a moving part, which never can be so accurate. At the precision you have been testing, changes of the mirror position in sub micrometer will show as change in focus position. So if calibrating focus will only last for a few days or maybe even hours, and calibrating it takes you 20 minutes, then it would not be an efficient solution for most photographers.

For this reason I even never bothered to adjust my PDAF. I live in a place where humidity can change by 70% in only one day, which I am sure will ruin all micro adjustments. If I need this accurate, I shoot CDAF on sensor, which with my camera is super accurate.

Posted on Oct 12, 2013 at 07:51 UTC
On Preview:canon-eos-70d (1333 comments in total)
In reply to:

HubertChen: Canon made a dramatic technological breakthrough: Sensor based AF has now the speed of OVF AF and at the same time is much more accurate. If you put this sensor into an LCD Viewfinder camera, the advantages become more obvious:

1) Camera is about 100 USD lower cost, because the complete OVF, plus mirror mechanism, plus additional PDAF sensor is removed, plus great simplification in firmware.
2) New LCD viewfinder are becoming more appealing than OVF: Larger image, more display information, depth of field preview
3) More accurate AF. Important to anyone with fast lenses who like to shoot shallow depth of field

This will be the winning camera and Canon just delivered the last missing piece to the puzzle: Sensor AF with no compromise. Big news!

About the PDAF inaccuracies shown in the Article. Anyone shooting very fast lenses in close distance knows these problems. Any PDAF camera has it. It is an inherent System Problem, not a dpreview staff problem!

@ Ralf B
Exactly! The Sony SLT is an improvement over the conventional DSLR in that it makes the mirror mounted in a fixed position instead making it move. This is an important simplification and this will make for less discrepancy of PDAF with real focus on the sensor. But still you have two AF systems than need to be developed and manufactured, one of which still need to be calibrated, with calibration being an expensive process in production.

Instead once you go for electronic viewfinder and the new Canon Sensor, you remove the redundant development and production of 2 AF systems and remove calibration.

Considering that production cost of mechanical parts is getting more expensive and production cost of electronic parts is getting lower cost, it is clear where this industry is going.

Posted on Oct 12, 2013 at 07:42 UTC
On Preview:canon-eos-70d (1333 comments in total)

@ Andy Westlake, Shawn Barnett and Richard Butler

Great Article, great research, great testing. Thanks so much for identifying the dramatic breakthrough Canon delivered and for explaining it in great writing. I truly enjoyed it. Keep up your excellent work! You made me read a Camera review cover to cover of a system I do not have :-)

Posted on Oct 11, 2013 at 16:34 UTC as 80th comment
On Preview:canon-eos-70d (1333 comments in total)

Canon made a dramatic technological breakthrough: Sensor based AF has now the speed of OVF AF and at the same time is much more accurate. If you put this sensor into an LCD Viewfinder camera, the advantages become more obvious:

1) Camera is about 100 USD lower cost, because the complete OVF, plus mirror mechanism, plus additional PDAF sensor is removed, plus great simplification in firmware.
2) New LCD viewfinder are becoming more appealing than OVF: Larger image, more display information, depth of field preview
3) More accurate AF. Important to anyone with fast lenses who like to shoot shallow depth of field

This will be the winning camera and Canon just delivered the last missing piece to the puzzle: Sensor AF with no compromise. Big news!

About the PDAF inaccuracies shown in the Article. Anyone shooting very fast lenses in close distance knows these problems. Any PDAF camera has it. It is an inherent System Problem, not a dpreview staff problem!

Posted on Oct 11, 2013 at 16:29 UTC as 81st comment | 2 replies
On Preview:canon-eos-70d (1333 comments in total)
In reply to:

ijustloveshooting: what a lame that Conventional, OVF autofocus screws all the time...then what's the point of a dslr?

I have shot with a variety of cameras and if you use an extreme narrow depth of field lens at close focal distance every PDAF I have shot with was off, about the same as shown in the Article. So this Article is very much in line with reality. If you shoot with lenses of smaller apertures you will never see these problems.

Posted on Oct 11, 2013 at 16:16 UTC
On Preview:canon-eos-70d (1333 comments in total)
In reply to:

ManuelVilardeMacedo: It is ridiculous that some blame the test for the poor OVF AF results!
As for me, Canon can include their 'dual pixel' autofocus system among its least of Most Relevant Innovations. People should congratulate the ones who developed this technology, as it's definitely an advance for photography.
...Still it puzzles me to see manual focus works even better than 'dual pixel'. One would be forgiven to ask why they bothered inventing autofocus at all.

They bothered because of speed. Try to manual focus reaching the accuracy level as described in here on any moving subject and you will get dramatically better results with AF!

Posted on Oct 11, 2013 at 16:12 UTC
On Preview:canon-eos-70d (1333 comments in total)
In reply to:

57even: So to get this camera to focus properly you have to hold it in front of you like a compact and focus using the rear screen? I am the only one who thinks this doesn't really move the game forward in any meaningful way?

You can use an LCD viewfinder and use the camera same way as an optical viewfinder, except you have a much larger, more immersive viewfinder.

If not to your liking, you can at least recognize the progress in live view and look forward to the time when they combine this sensor with a great LCD viewfinder.

The time is near where LCD viewfinder will be preferable over optical viewfinder. Better user experience paired with lower cost.

Posted on Oct 11, 2013 at 07:23 UTC
On Curiosity in the WiFi Remote Capture challenge (3 comments in total)

This picture made me smile from ear to ear! Nice shot and congrats to deserved win

Direct link | Posted on Oct 11, 2013 at 06:56 UTC as 1st comment
On Images from the past: Circular snapshots from the Kodak 1 news story (89 comments in total)
In reply to:

mister_roboto: Accounting for inflation in USD it'd be about $600 today.

Thanks for these calculations. It puts the whole thing into a different perspective.

Direct link | Posted on Oct 7, 2013 at 07:56 UTC
On Images from the past: Circular snapshots from the Kodak 1 news story (89 comments in total)
In reply to:

SRT3lkt: people are happier back then

This always has been the excuse of the unhappy ones. Happiness is is the result of a person's hard work to become happy. It is not about a time or place.

Direct link | Posted on Oct 7, 2013 at 07:56 UTC
In reply to:

HubertChen: The facts make the intention super clear, that the intended use of the Memorial was Public domain:
1) The Artist Gaylord was paid 0.8 Million USD to create the war memorial for a public park
2) The Artist was contracted directly by US Congress

Leaders lead society by example. The Congress leading by example on how to make law (agreements) to create piece and understanding. The Artists lead by example on how to understand intention and express intention.

Example of Congress: Not capable to manage paperwork necessary to run a public park. Giving away 0.8 Mio USD for Art to be displayed in a public Park and still not having purchased the copyrights is embarrassingly stupid. Also not capable to have a friendly relationship with the Artist.

Example of the Artist: Greedy Slimy Snake. Even he already got paid 0.8 Mio USD and his work is used exactly as intended by his customer, he found a legal way to make something very clear becoming very confusing, complicating the future of others.

...
You can see in responses in this place that for half of the people here this whole thing is very upsetting. Those are the once inexperienced with intellectual property license agreements and they feel it to be counter intuitive and nonsensical.

The other half instead are professionals and they ask: What do you want, this is how it is done.

My point is that it is perhaps time to change the way it is done. To make the standard way of doing business intuitive and the way a paying customer would expect, even and especially he is inexperienced. This would make for a more friendly and happy life for all participants.

We changed it for us, and we and our customers are certainly more happy.

When I was in my twenties I had a major lawsuit every year ( which I usually won). Now I am in my forties and I have not had a lawsuit in the last 10 years and I am a much, much happier person and so are my customers, staying with me for 10 years plus.

I hope this makes more sense now?

Direct link | Posted on Oct 3, 2013 at 15:31 UTC
In reply to:

HubertChen: The facts make the intention super clear, that the intended use of the Memorial was Public domain:
1) The Artist Gaylord was paid 0.8 Million USD to create the war memorial for a public park
2) The Artist was contracted directly by US Congress

Leaders lead society by example. The Congress leading by example on how to make law (agreements) to create piece and understanding. The Artists lead by example on how to understand intention and express intention.

Example of Congress: Not capable to manage paperwork necessary to run a public park. Giving away 0.8 Mio USD for Art to be displayed in a public Park and still not having purchased the copyrights is embarrassingly stupid. Also not capable to have a friendly relationship with the Artist.

Example of the Artist: Greedy Slimy Snake. Even he already got paid 0.8 Mio USD and his work is used exactly as intended by his customer, he found a legal way to make something very clear becoming very confusing, complicating the future of others.

Dear Enconmiast,

Thank you for your detailed and very precise response. I agree with all what you said. I apologize that my previous writing was not clear. I meant the intent of the customer, not the intent from the Artist. Customer being in this case the Congress and the extended customer being the public.

I have been on the selling and contracting end of such intellectual property license agreements for the past 25 years, so you can assume I am sufficiently experienced.

In all this time to anybody who was new to the method that the Artist / photographer remained owner of the intellectual property was not intuitive to the customer and in many cases once the customer understood the idea, he felt cheated.

For ourselves we eventually gave up using this license model, as we considered it more important to keep the customer happy and consider us reasonable and for that reason come back and give us repetitive business.

Direct link | Posted on Oct 3, 2013 at 15:25 UTC
In reply to:

Sirandar: There are 2 camps

Camp 1 will agree because they want creative works to generate as much income as possible in as many ways as possible.

Camp 2 doesn't want to pay directly or indirectly for this.

Basically the US gov made a stupid mistake paying 0.8 million for a public monument and not getting the rights and the artist is cashing in on it.

I would have been interesting to follow the flow of money all though this monument project to see how it flowed and into who's pocket but we will never know that.

Judging from the picture at least the artist is talented .... sometimes we pay 0.8 million for an eyesore.

Thanks Sirandar for this summary

may I add a Camp 3: This should not have gone to court!
Camp 3 agrees in principle on Camp 1. The agreement said that the Artist is still copyright holder. If going to court, copyright law must be uphold, or other Artists lose the only power they have to protect their intellectual property. However in this case the intent for the monument was for use in public domain and using a photograph of it is using it as it was intended in spirit when the whole project was started. That the Artist is now fighting his employer will make those even more hesitating who considered to contract an Artist. This simply makes life harder for those Artists fighting to make a living. More scared patrons = less earning. So Camp three is this should never has gone to court. Who plays on this level has the privilege and responsibility to be a role-model and show how to successfully build Win-Win relationships.

Direct link | Posted on Oct 3, 2013 at 04:03 UTC
In reply to:

HubertChen: The facts make the intention super clear, that the intended use of the Memorial was Public domain:
1) The Artist Gaylord was paid 0.8 Million USD to create the war memorial for a public park
2) The Artist was contracted directly by US Congress

Leaders lead society by example. The Congress leading by example on how to make law (agreements) to create piece and understanding. The Artists lead by example on how to understand intention and express intention.

Example of Congress: Not capable to manage paperwork necessary to run a public park. Giving away 0.8 Mio USD for Art to be displayed in a public Park and still not having purchased the copyrights is embarrassingly stupid. Also not capable to have a friendly relationship with the Artist.

Example of the Artist: Greedy Slimy Snake. Even he already got paid 0.8 Mio USD and his work is used exactly as intended by his customer, he found a legal way to make something very clear becoming very confusing, complicating the future of others.

@Enconmiast
The difference between agreement by the letter and by intent

By the letter:
You are referring to the letter of agreement. As it appears the government was stupid and signed an agreement with the Artist where he still remained sole copyright to the Artwork. But in this case clearly the letter of the agreement is in conflict with the intent of the agreement. This is why all parties involved thought they can take a picture without commission. They thought it is OK and inline with the intent. None of the parties ever had the intention to steal from the party.

Intent:
I am referring to the intent. The Spirit. The core idea. The heart and soul of the agreement. It is about two parties really understand each. They set out to make a Win-Win project and then continue to behave causing Win for the other party.

Win-Win works great. People working happy together. As a result there are usually many follow up projects

I hope this is something you feel is right?

Direct link | Posted on Oct 3, 2013 at 03:40 UTC
Total: 592, showing: 61 – 80
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