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02-18-2015, 09:19 AM   #121
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QuoteOriginally posted by DavidSKAF3 Quote
1,3, and 6???
If you read down the thread, I tell them after someone gets it right.... I'm not sure I remember.

02-18-2015, 09:28 AM   #122
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QuoteOriginally posted by normhead Quote
If you read down the thread, I tell them after someone gets it right.... I'm not sure I remember.

Hi Norm,


Actually I wanted to make my own guesses without any influence from previous posters. I'll go back and look for the answers now.
02-18-2015, 09:29 AM   #123
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Probably a trick question. I bet they were all taken with an iphone!
02-18-2015, 09:33 AM - 1 Like   #124
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Guys this is simple physics its obvious that given the different focal lenght the longer one will always render better - here is simple example d700 and 70-200: 70mm apsc and about 105 on FF (i have adjusted to cover same area): no doubt for me who is the winner:





and normhead the exmples you've submitted aren't crops we are pixel pipping here besides given the size of the pictures you wouldn't tell the difference between my phone and my d800.... its pointless.

02-18-2015, 09:44 AM   #125
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QuoteOriginally posted by filorp Quote
Guys this is simple physics its obvious that given the different focal lenght the longer one will always render better - here is simple example d700 and 70-200: 70mm apsc and about 105 on FF (i have adjusted to cover same area): no doubt for me who is the winner:





and normhead the exmples you've submitted aren't crops we are pixel pipping here besides given the size of the pictures you wouldn't tell the difference between my phone and my d800.... its pointless.
The only thing I'd note here is that anyone can fudge a set of pictures. I look on Imaging Resources for comparisons, and my observation would be, they do a much better job with APS-c than you do.

Here's a D610 compared to a K-3, pixel peeping... my question would be, where did you mess up? Your APS-c image should appear to be sharper based on more DoF.


There may be an advantage in the eyes of optical physics, that doesn't mean it makes a practical difference. But since you brought up optical physics as part of your argument, maybe you could work out what the difference would be in microns and suggest whether or not it's a difference the human eye can perceive or that a camera can resolve.

Last edited by normhead; 02-18-2015 at 09:49 AM.
02-18-2015, 09:49 AM   #126
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where they did mess up? i have used the same settings the same sharpening the same lens switched just to crop and ff mode..... nothing has been messed up!!! beside as i have stated before the smaller apperture hole the difference will vanish..... what aperture did they use? f8?

and did you notice famous pentax red colour rendering fine details....? its completely unacceptable.....
02-18-2015, 09:49 AM   #127
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The trouble for me here is that while the pink on the right seems too strong, for all I know, it really is that strong!
02-18-2015, 10:02 AM   #128
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QuoteOriginally posted by filorp Quote
where they did mess up? i have used the same settings the same sharpening the same lens switched just to crop and ff mode..... nothing has been messed up!!! beside as i have stated before the smaller apperture hole the difference will vanish..... what aperture did they use? f8?

and did you notice famous pentax red colour rendering fine details....? its completely unacceptable.....
Your APS-c image is soft... that's where you messed up. You blame it on the camera. Having used a K-5, and still owning one... I'm saying, I can do better.

Now about those numbers derived from optical physics you were about to share with us... you seem to have forgotten to post them.

Amazing how many people claim optical physics is on their side, experts and novices alike,who have never done the math on the refraction in a compound lens, in their whole life.


Last edited by normhead; 02-18-2015 at 10:14 AM.
02-18-2015, 10:05 AM   #129
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QuoteOriginally posted by filorp Quote
and norm head ... given the size of the pictures you wouldn't tell the difference between my phone and my d800.... its pointless.
I've pointed that out before. Didn't take.
02-18-2015, 10:37 AM   #130
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normhead i am not physicist - but i can use my imagination without wasting - as i can see now - about 15 minuts of my time to create the examples, and get to the simple conclusion that competition betw. 70mm vs 105mm will always result in 105mm finest details despite that the angle of the optical whole is the same - that's because compacts are so inferior not because "less megapixels". The difference are almost insignificant in some cases especially in order to create images up to 5x7 or even A4 - the six pack for those of you who can determine where is actually the border line between usability apsc vs FF!!!
02-18-2015, 11:13 AM   #131
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QuoteOriginally posted by filorp Quote
normhead i am not physicist - but i can use my imagination without wasting - as i can see now - about 15 minuts of my time to create the examples, and get to the simple conclusion that competition betw. 70mm vs 105mm will always result in 105mm finest details despite that the angle of the optical whole is the same - that's because compacts are so inferior not because "less megapixels". The difference are almost insignificant in some cases especially in order to create images up to 5x7 or even A4 - the six pack for those of you who can determine where is actually the border line between usability apsc vs FF!!!
I think that full frame is better at the extremes. High iso situations, printing really big, really shallow depth of field. The question in my mind is how many folks are really pushing the envelope of what is possible with APS-C. As to seeing a difference in "real world" situations between say, a D600 and K3, I doubt you would. This is assuming relatively low iso (below iso 800), a lens that is stopped down a little and a good quality lens (even a DA 50 is more than adequate on a K3).

People for whatever tend to focus on the extremes and yes, at iso 6400 a full frame camera is better. If you print 36 inches on a side, you'll see a difference. I just don't know many people who do those things a whole lot.

Griping about not seeing a difference between photos at web resolution is the point. That's what most people are doing with their photos -- printing them at 8 by 10 and smaller and posting at 2000 pixels and smaller on the web. So, no, most of them won't see a difference.
02-18-2015, 11:33 AM   #132
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QuoteOriginally posted by filorp Quote
normhead i am not physicist - but i can use my imagination without wasting - as i can see now - about 15 minuts of my time to create the examples, and get to the simple conclusion that competition betw. 70mm vs 105mm will always result in 105mm finest details despite that the angle of the optical whole is the same - that's because compacts are so inferior not because "less megapixels". The difference are almost insignificant in some cases especially in order to create images up to 5x7 or even A4 - the six pack for those of you who can determine where is actually the border line between usability apsc vs FF!!!
It's never, in the years I've been here been determined. People have examined up to 16x20 without being able to say one image is better than the other. We have one guy who is saying he's going to compare 60x40 prints against each other, and we are all waiting....

The FF ticket is the Narrow DoF and therefore, smoother bokeh in portraits... and higher resolution if you need it. Just no one has actually shown that they need it. Some have actually shown it doesn't make their images more pleasing. No one has ever been able to definitively show where the magic point is that a specific resolution becomes necessary, and that's because it's a sliding variable based on the specific image involved. It might make a difference to a particular image, it might not. As for concocting artificial situations where one format excels and the other doesn't, specifically to show off how one format is better than the other, that's just a stupid game only fools engage in. The pro knows how to get what he wants with the system he has. He doesn't sit around saying ' I have to use this lens at this distance," to prove which does better.

Thanks for sharing the products of your imagination. We're all impressed I'm sure.
02-18-2015, 11:35 AM   #133
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QuoteOriginally posted by jsherman999 Quote
Jeff, I think you're using some old information there.

A larger pixel will collect more light than a smaller pixel, but an array of smaller pixels over the same area will collect the same amount of light. You can reach a point where your individual pixel efficiency hits a wall if you make them too small, and that wall is always a moving target as sensor tech improves, but it's a myth that larger pixels are the reason FF sensors show better noise/DR performance.

Larger sensors perform better because they get more light from the lens used over a larger area. It's not directly related to pixel size.

See this link for a basic overview, or consider D800 vs. D7000/K5, which have the same size pixels of the same sensor generation.

---------- Post added 02-17-15 at 05:57 PM ----------

Thanks for the reference link by the way. Jay, given that this is the way the market tends to be moving, i.e. more pixels, do you have any comments about how the design of the A7s sensor relates to this discussion. Not trying to argue the point about more pixels at all, but somehow Sony managed to preserve useful dynamic range into very high ISO territory. I don't even care about discussions of why someone would want a camera like this - just trying to understand how this eccentric design managed to achieve a different, but useful result. (Or anyone else who has some useful comments about this design feature) (Not trying to pitch Sony here, but this sensor to me is one of the most interesting things that came out of 2014) Graph is courtesy of DXOmark of course.

[IMG][/IMG]

Last edited by philbaum; 02-18-2015 at 12:11 PM.
02-18-2015, 11:39 AM   #134
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Con's.....I would have to lie like all hell to the wife and then buy her a new diamond or something to shut her up !
Pro's......I DONT have a wife !


Seriously....Im all about landscapes. My 2 dozen lenses from film days will be given new life and once again....my wide will work as a wide. That's what its about for me. That's it.
I just hope they don't try and cram much more than 36 pickles in the jar !

Last edited by Dlanor Sekao; 02-18-2015 at 11:48 AM.
02-18-2015, 11:50 AM   #135
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QuoteOriginally posted by philbaum Quote
Thanks for the reference link by the way. Jay, given that this is the way the market tends to be moving, i.e. more pixels, do you have any comments about how the design of the A7s sensor relates to this discussion. Not trying to argue the point about more pixels at all, but somehow Sony managed to preserve useful signal to noise levels into very high ISO territory. I don't even care about discussions of why someone would want a camera like this - just trying to understand how this eccentric design managed to achieve a different, but useful result. (Or anyone else who has some useful comments about this design feature) (Not trying to pitch Sony here, but this sensor to me is one of the most interesting things that came out of 2014) Graph is courtesy of DXOmark of course.

[/url][/IMG]
The Sony A7s uses lenses to collect light from the entire area of the sensor. A traditional sensor collects make 40 to 60% of the photons hitting it. The last few years Sony has concentrated on improved performance by collecting more of the photons available, so essentially achieving better performance out of the sensor size model... there is obviously a limit to that. But until the Sony A7s sensor, I don't think anyone had approached it. My guess is the A7s model is more photons gathered to produce a more even signal, reducing noise.

In terms of sensor sites and noise, you have to remember, an FF set at 200 ISO and f5.6 and 1/60sec is using the same amount of light as an APS-c sensor at 200 ISO ƒ4 and 1/60 sec. People tend to say the FF sensor always has more light to work with... but it's a small difference, one stop. If you were shooting with the APS-c at ƒ2.8, you'd be using twice as much light to form your APS-c image as you used for your 5.6 FF image. The more light thing is completely dependant on the setting used. And in the above sequence the APS-c would have used "more light". A better thing would be which camera has "enough light". If the camera can get "enough light" it doesn't matter if another camera gets more.
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