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03-07-2014, 06:48 AM   #76
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read noise and QE as well

QuoteOriginally posted by dtmateojr Quote
Finally managed to read that link you posted. I stopped at this:

The concepts of, and connections between, total light, DOF, and noise, are much more easily understood in terms of aperture rather than f-ratio, especially when comparing different formats. While the same f-ratio will result in the same exposure (where exposure is the density of light that falls on the sensor -- photons / mm˛), regardless of the format, the aperture diameter, together with the shutter speed, determines the total amount of light that falls on the sensor, where the same total amount of light falling on the sensor results in the same noise in the photo, for equally efficient sensors. In addition, for a given perspective, framing, display size, viewing distance, and visual acuity, the same aperture diameter will result in the same DOF.
Wow, you only got a few paragraphs down! (It was late, I understand.)

QuoteQuote:

Clearly, that does not take into consideration the intensity of light which is affected by distance. It is very easy to see the big flaw in that explanation. If you consider only the total amount of light as the variable that affects noise then I would have to ROFL. Do you do flash photography? Do you know what a guide number is?[COLOR="Silver"]
The photon shot noise is what he's talking about at first. If you would have read even a little further you'd have seen how he talks about the other factors, like read noise (the additional noise added by the sensor and supporting hardware) and QE (proportion of photons falling on the sensor that are converted into electrons.) When you're discussing sensors of the same tech (as you and I were - remember when I said K5 vs D800 up there?) then you presume the read noise and QE will be close enough that the other sources of noise besides shot noise are going to be about the same between both sensors. Your A900 is an example of a sensor that had read noise and a low QE dominating as the source of noise a bit quicker than say the D600 does, and that's why the D600 is a much 'cleaner' sensor even though they have the same MP (24) and size. The read noise really takes over as a factor when the light gets really low, and if the QE is low as well... that's probably a main problem with the older FF sensors, and it's why newer aps-c sensors hold their own against those despite the difference in sensor area.



QuoteQuote:
Is that an insult?
Just responding in kind. If you read back, I started out much more respectful in tone. After multiple flippant "LOL!" one liner posts from you in which you didn't even try to read what I wrote or linked, I decided you weren't worth the facade. (Also, just thought it was amusing that when your other misconceptions were challenged by someone else in that other thread, you didn't whip out the "I have a physics degree!" as a last resort then, you said you were just a physics major. Your bona fides seemed to have ramped up since then, is all

.


Last edited by jsherman999; 03-07-2014 at 06:59 AM.
03-07-2014, 07:08 AM   #77
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Don't feel bad dtmateojr, I've been through the same thing with Jay and he's also on my ignore list... funny, I can read your posts and know exactly what Jay is saying because I've been through it with him so many times before, including the innuendo and insults. He's not a bad guy though, he just seems to be a little confused in some technical concepts. If you can get him down to talking cameras and lenses and stuff he has things to contribute. But he's not at all knowledgeable about current Pentax bodies, or anything Pentax has released in the last 4 years.
03-07-2014, 07:53 AM   #78
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HI Norm! I'm hurt!

QuoteOriginally posted by normhead Quote
Don't feel bad dtmateojr, I've been through the same thing with Jay and he's also on my ignore list... funny, I can read your posts and know exactly what Jay is saying because I've been through it with him so many times before, including the innuendo and insults. He's not a bad guy though, he just seems to be a little confused in some technical concepts.
Norm, Norm Norm The FF threads won't be the same without you!

.

Last edited by jsherman999; 03-07-2014 at 08:22 AM.
03-07-2014, 01:15 PM   #79
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QuoteOriginally posted by normhead Quote
Don't feel bad dtmateojr, I've been through the same thing with Jay and he's also on my ignore list... funny, I can read your posts and know exactly what Jay is saying because I've been through it with him so many times before, including the innuendo and insults. He's not a bad guy though, he just seems to be a little confused in some technical concepts. If you can get him down to talking cameras and lenses and stuff he has things to contribute. But he's not at all knowledgeable about current Pentax bodies, or anything Pentax has released in the last 4 years.

I feel that he needs a big cluebat His myth is actually a good topic for discussion in my next blog post. I hope he keeps spreading nonsense so I don't have to think hard on what to post next.

03-07-2014, 02:40 PM   #80
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So what did I miss???
03-07-2014, 02:40 PM   #81
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bloggin' to oblivion

QuoteOriginally posted by dtmateojr Quote
I feel that he needs a big cluebat His myth is actually a good topic for discussion in my next blog post. I hope he keeps spreading nonsense so I don't have to think hard on what to post next.
Actually, I'm looking forward to it, because I still can't figure out what specifically you think my 'myth' is Maybe you'll be a bit more descriptive in your blog post. Will you allow comments?

---------- Post added 03-07-14 at 03:51 PM ----------

QuoteOriginally posted by Pepe Le Pew Quote
So what did I miss???
Where to start.... 'dtmateojr ' does not agree with what I posted here, although it's hard to tell what he specifically disagrees with. (My growing suspicion is that he didn't really read it carefully, and he may think it's saying something it's not, based on his pithy one-liners and follow-ups.)

Anyway. He also doesn't believe what his eyes are telling him in this post (and what any knowledge of downsampling algorithms like bicubic sharper should predict anyway.) And he doesn't think that higher resolution can compensate for noise, and shown (and linked and discussed) here and here (K3 post) and many other places. Finally, he seems to call Joseph James crazy and equivalence wrong here.

Oh, and he appears to have possibly received a physics degree between 2/23 and last night.

I think that pretty much brings things up to speed!

.

Last edited by jsherman999; 03-07-2014 at 03:19 PM.
03-07-2014, 03:28 PM   #82
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QuoteOriginally posted by jsherman999 Quote
Actually, I'm looking forward to it, because I still can't figure out what specifically you think my 'myth' is Maybe you'll be a bit more descriptive in your blog post. Will you allow comments?

---------- Post added 03-07-14 at 03:51 PM ----------



Where to start.... 'dtmateojr ' does not agree with what I posted here, although it's hard to tell what he specifically disagrees with. (My growing suspicion is that he didn't really read it carefully, and he may think it's saying something it's not, based on his pithy one-liners and follow-ups.)

Anyway. He also doesn't believe what his eyes are telling him in this post (and what any knowledge of downsampling algorithms like bicubic sharper should predict anyway.) And he doesn't think that higher resolution can compensate for noise, and shown (and linked and discussed) here and here (K3 post) and many other places. Finally, he seems to call Joseph James crazy and equivalence wrong here.

Oh, and he appears to have possibly received a physics degree between 2/23 and last night.

I think that pretty much brings things up to speed!

.

Usually I am the king of one-liners......

K-30 has worked very well so far (for me that is)........... No need to update just yet
03-07-2014, 03:56 PM   #83
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Anyone else feel that the last three pages or so could have (or should have) been conducted by PM? I mean, we all know these points, they've been hashed out thousands of times all over the net. Nobody wins these things.

03-07-2014, 04:00 PM   #84
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QuoteOriginally posted by filoxophy Quote
Anyone else feel that the last three pages or so could have (or should have) been conducted by PM? I mean, we all know these points, they've been hashed out thousands of times all over the net. Nobody wins these things.

Agreed....
03-07-2014, 05:14 PM   #85
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QuoteOriginally posted by filoxophy Quote
Anyone else feel that the last three pages or so could have (or should have) been conducted by PM? I mean, we all know these points, they've been hashed out thousands of times all over the net. Nobody wins these things.

Yep nobody wins. In the end we will just have to accept that some people will try to bend physics so they could justify the money they spent on a D800 which turns out to be just the same as a Pentax that costs less than a third of the price They probably believe in unicorns as well LOL!
03-07-2014, 06:31 PM   #86
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And here's my blog post:

http://dtmateojr.wordpress.com/2014/03/08/debunking-the-myth-of-full-frame-superiority/
03-07-2014, 10:41 PM   #87
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QuoteOriginally posted by dtmateojr Quote
Yep nobody wins. In the end we will just have to accept that some people will try to bend physics so they could justify the money they spent on a D800 which turns out to be just the same as a Pentax that costs less than a third of the price They probably believe in unicorns as well LOL!
For the record (not that you will read this,) I'm not trying to justify anything - if anything it looks like you were trying to justify your old D700 (D3) over the K3 - something I tried to bring back to reality by showing how your 'more noise comes with more MP' was not necessarily true, for one thing.

The argument arced into a few other areas that you're a bit weak on ('more MP does not compensate for noise' (false,) an 'f-stop is an f-stop on any format' (misleading - in the same way saying 'focal-length is focal length on any format', or 'a 185HP engine is a 185HP engine in any vehicle, sub-compact or semi-trailer' - true only in an aspergers-like, missing the point way.) If I've been an advocate for anything, it could be summarized with 'more MP isn't bad, and is worth investing in, all else equal.' and that can apply to aps-c as easily as FF.

By the way, reading 3 paragraphs of Joseph James' wide-ranging equivalence paper (he's not an FF advocate, by the way, something you would know if you actually read it,) and then declaring the whole thing hogwash shows consistency - it's exactly the same behavior you've been displaying in this thread. I honestly don't now if it's a reading comprehension thing, or an attention span thing, or the result of a desultory education, but hopefully it's something you'll get a handle on.


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03-07-2014, 10:45 PM   #88
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I see that you guys have ran with this pretty hard!
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