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03-13-2013, 05:07 AM   #61
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QuoteOriginally posted by Digitalis Quote
Don't laugh, but I have actually bought boxes full of nikon lens caps
Your a braver man than me, I wouldn't have admitted that here on this forum.

It's almost heresy and you could get burned at the stake.

03-13-2013, 07:13 AM   #62
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Not only that but last time I checked imaging resources, because I used to think that 24 MP was a marketing ploy, and to a certain extent I still do. But the tested resolution at IR of a Nikon D3200 (24 MP) was around 2400 Lw/Ph a K-5 was almost 2200 Lw/Ph so using what ever test that was, there was about a 10 % increase in resolution compared to a a K-5. That doesn't seem like a lot... and whether or not you can actually see a difference based on a 10% increase in resolution and under what circumstance it might be true.. that has yet to be in any meaningful way determined. In other words, it may well be a marketing ploy because in the real world it makes no difference.

But just to keep it in perspective, the same test tested a D600 t a little over 2600 Lw/Ph. jIf you can push the K-5 to 24, paying for an extra 200 and changing systems to get it would be insanity. Just as paying for 400 going to a D600 on any other than personal taste is pretty much insanity. But, if you were absolutely convinced you had to have a D600 for the resolution, you might get by with 24 Mp APS_C. It would certainly be my preference.

Most lenses, if you look at the charts begin losing resolution after F 5.6. So If you're talking diffraction limiting, You're actually already losing resolution going to f8, with most lenses. I'd be interested in finding out if it would be worse with a 24 Mp camera, or just more of the same. (Compound or concurrent.)

The thing is, once a K mount APS-c lens gets to 24 MP, then for long lenses, compared to a D600, the 1.5 crop factor will come into play and the K image will be equivalent and my 400mm lens will be the equivalent of a 600mmm on a D600, probably with a loss of about 200 Lw/ph of resolution.. For telephoto work this gives the APAS-c system a huge advantage. And for landscape... at 24 Mp, the K- image will in fact be superior to an cropped D800 image. Think of the K- image as pre-cropped with a higher pixel density.

I have never seen anyone prove in blind tests that they can tell the difference between an image done a 2200 Lw/Ph and one printed from a 2400 or even 2600 Lw/Ph image (on images with sensors capable of over 2000 lw/ph.)

According to the 7.1. diffraction limit, and the fact that 5.6 provides the sharpest images on most lenses, there's still more room to pack in more pixels. Until the sensor is diffraction limited @ 5.6 there's room for improvement. Just guessing but it looks like (without actually doing the math) APS_c can hit 30 mp before it hits it's diffraction ceiling (the point at which the resolution is limited by the lens, not the sensor, as long as the sensor isn't diffraction limited at less than 5.6, the sensor will still be resolving the sharpest output of the lens.) , meaning it still has room for future growth.

Last edited by normhead; 03-13-2013 at 07:25 AM.
03-13-2013, 10:35 AM   #63
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QuoteOriginally posted by normhead Quote
According to the 7.1. diffraction limit, and the fact that 5.6 provides the sharpest images on most lenses, there's still more room to pack in more pixels. Until the sensor is diffraction limited @ 5.6 there's room for improvement. Just guessing but it looks like (without actually doing the math) APS_c can hit 30 mp before it hits it's diffraction ceiling (the point at which the resolution is limited by the lens, not the sensor, as long as the sensor isn't diffraction limited at less than 5.6, the sensor will still be resolving the sharpest output of the lens.) , meaning it still has room for future growth.
According to the Cambridge calculator: The diffraction limit is f7.4 for 24mp. The diffraction limit hits f5.6 at 42mp.
03-13-2013, 10:53 AM   #64
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QuoteOriginally posted by normhead Quote
If you can push the K-5 to 24, paying for an extra 200 and changing systems to get it would be insanity.
...in terms of resolution for a couple of not-defined lenses.

Each case has to be evaluated on it's own, I think.

Let's say you want a picture at 50mm equivalent at f/1.4? How much would that cost on the Nikon? The Pentax? What would resolution be on the Nikon? The Pentax?

85mm equivalent?

35mm equivalent? F/1.4? F/2.8?

Are you considering that you can crop the FF and have a system with a few less primes? Or even perhaps use zooms instead of primes?

Your 'insanity' comment fails to recognize that other people take other pictures with other priorities.

03-13-2013, 12:49 PM   #65
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QuoteOriginally posted by ElJamoquio Quote
...in terms of resolution for a couple of not-defined lenses.

Each case has to be evaluated on it's own, I think.

Let's say you want a picture at 50mm equivalent at f/1.4? How much would that cost on the Nikon? The Pentax? What would resolution be on the Nikon? The Pentax?

85mm equivalent?

35mm equivalent? F/1.4? F/2.8?

Are you considering that you can crop the FF and have a system with a few less primes? Or even perhaps use zooms instead of primes?

Your 'insanity' comment fails to recognize that other people take other pictures with other priorities.
Next time quote me....

QuoteQuote:
Just as paying for 400 going to a D600 on any other than personal taste is pretty much insanity.
I took personal taste into account. What else do you think might be important? or are you just going to try and get into it again? 95% of the Pentax world doesn't want or need FF. Most of us at looking for ways to avoid FF. Get used to it. It's been that way forever.

QuoteQuote:
Are you considering that you can crop the FF and have a system with a few less primes? Or even perhaps use zooms instead of primes?
Yes..
Cropping any FF system doesn't give you 24 MP or as much resolution as pre-cropping with a 24 MP APS-c system. The D800 did catch up with 16 MP APS-c systems, but, that's old news.

QuoteQuote:
Let's say you want a picture at 50mm equivalent at f/1.4? How much would that cost on the Nikon? The Pentax? What would resolution be on the Nikon? The Pentax?
That's not the strength of APS-c. The strength of APS-c is when I buy my A400 5.6 lens for $450 used, and the equivalent FF system at 600mm, is over $12,000. That right there is why even after you go FF, you'll still want to carry a 24 MP APS-c in the same mount. When using my 400, I still usually crop half the image. How would cropping 3/4s of the image help me at all? It's at the long focal lengths APS-c really makes sense. In the middle ranges it's a saw off you can argue forever. Wide angle, I myself and I suspect many others would love to use a 31 Ltd on an FF camera. But it's not essential. We can still get an acceptable shot with the 21 Ltd.

I'm not saying there aren't advantages to FF, advantages that will become more apparent as pixel densities increase, APS-c sensors will become seriously diffraction limited before FF will... I'm talking about a snapshot in time, when 24 MP APS-c cameras exist, and get almost the same resolution as 24 MP FF cameras do.

I've actually never said there weren't reasons to go FF. A lot of FF advocates like to put words into my mouth. There are lot's of choices based on personal preferences that make FF attractive.

Last edited by normhead; 03-13-2013 at 01:09 PM.
03-13-2013, 08:57 PM   #66
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QuoteOriginally posted by normhead Quote
Next time quote me....
I did quote you.


QuoteOriginally posted by normhead Quote
I took personal taste into account.
I wasn't talking at all about personal taste.


QuoteOriginally posted by normhead Quote
What else do you think might be important? or are you just going to try and get into it again?

Any time you make sweeping statements that I don't feel are either not accurate or not applicable to the discussion...


QuoteQuote:
95% of the Pentax world doesn't want or need FF.
Like this.


QuoteQuote:
Most of us at looking for ways to avoid FF.
Or this


QuoteQuote:
It's been that way forever.
Or this



QuoteQuote:
I buy my A400 5.6 lens for $450 used, and the equivalent FF system at 600mm, is over $12,000
or this

... I'll mention that I think you're wrong or that I think your assumptions or wrong or I'll ask what your assumptions are or I'll give a set of common assumptions for which your statements are false.

You talk about saving a couple of hundred dollars by going APS-C and require a set of lenses that gets the same resolution as FF lenses would get, but on APS-C? How is that a consistent set of assumptions? What lenses can support this? How much do equivalent lenses cost with the same resolution and same DOF cost for FF cameras?

What 600mm F/9 manual focus lens costs $12000?

etc...

Last edited by ElJamoquio; 03-13-2013 at 09:19 PM.
03-14-2013, 02:36 AM   #67
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QuoteOriginally posted by audiobomber Quote
You are overstating the numbers. Check this advanced diffraction calculator: Digital Camera Diffraction Resolution, Color & Micro-Contrast "Most will find that the f-stop given in the "diffraction limits extinction resolution" field tends to correlate well with the f-stop values where one first starts to see fine detail being softened." The calculated limit for 24mp on a 1.5X APS-C body is f/7.4. The limit for 16mp is f/9.1. That means that at any aperture up to f7.4, all of the resolution of the 24mp sensor will be useable. At apertures larger than f9.1, the 24mp body will have more resolution than a 16mp body. At apertures smaller than f9.1, they will show equal resolution.
Thanks for correcting me, Dan! But at least for me that doesn't change anything. Stopping down to f/9 isn't an unusual thing for me. So, if I end up with a 16 MP res then, the question at hand is: why not get a 16 MP camera. Furthermore I wonder how pixel size and high ISO performance correlate. With all I've done so far, the 14 MP res of my camera was never limiting factor. The high ISO performance on the other hand...
Cheers,
David
03-14-2013, 04:29 AM   #68
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QuoteOriginally posted by Davidw0815 Quote
Thanks for correcting me, Dan! But at least for me that doesn't change anything. Stopping down to f/9 isn't an unusual thing for me. So, if I end up with a 16 MP res then, the question at hand is: why not get a 16 MP camera. Furthermore I wonder how pixel size and high ISO performance correlate. With all I've done so far, the 14 MP res of my camera was never limiting factor. The high ISO performance on the other hand...
Valid points, David. A 24mp body may not be an improvement for you.

I want more pixels so I can crop hard with my DA*300 and be left with a printable remainder. Most of my lenses are losing resolution beyond f5.6 and most of my photos are taken at or below f5.6. With landscapes. I rarely feel I need to go beyond f8, especially with shorter lenses and their hyperfocal distances. The only time I regularly shoot with apertures smaller than f8 is for macro photography. For general photography I believe higher resolution will benefit me.

DR and high ISO performance are also critical, because I often shoot in low ambient light. I'm working with the assumption that these sensor parameters will not deteriorate by moving up to 24mp. I base this on the comparative tests at DXOMark for the Sony NEX5-N and NEX7. The 5N has the same sensor as the K-5 line. The 7 has the sensor supposedly used in the K-3. If you compare graphs on the link below, you will notice that the plots for the NEX5-N and NEX7 are very close, and even slightly favour the higher mp sensor. The K-5 II edges them out, but surely the Pentax recipe will elevate the 24mp sensor as it has the 16.

http://www.dxomark.com/index.php/Cameras/Compare-Camera-Sensors/Compare-came.../(brand3)/Sony

I haven't ruled out a K-5 IIs, but if there are no glitches in the K-3, if sensor performance is equal, and it contains the improvements I'm looking over and above the K-5 IIs (better AF-C tracking, faster CDAF, focus peaking), then it's a lock for me.

03-14-2013, 07:07 AM   #69
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QuoteOriginally posted by ElJamoquio Quote
I did quote you.




I wasn't talking at all about personal taste.





Any time you make sweeping statements that I don't feel are either not accurate or not applicable to the discussion...


Like this.


Or this


Or this



or this

... I'll mention that I think you're wrong or that I think your assumptions or wrong or I'll ask what your assumptions are or I'll give a set of common assumptions for which your statements are false.

You talk about saving a couple of hundred dollars by going APS-C and require a set of lenses that gets the same resolution as FF lenses would get, but on APS-C? How is that a consistent set of assumptions? What lenses can support this? How much do equivalent lenses cost with the same resolution and same DOF cost for FF cameras?

What 600mm F/9 manual focus lens costs $12000?

etc...
I have no idea what you just added to the discussion. Did you forget what we're talking about?

Quoting me and saying I'm wrong isn't adding anything. It's just you enjoying the internet to launch a personal attack.Maybe you should say what you think is true.

If you don't like my assumptions, give us better assumptions, if you don't like my numbers, give us numbers you think are better. Just quoting someone and saying your wrong...that's just like the Monty Python argument Clinic. That's not argument , that's contradiction.

An argument "An argument is an intellectual process while contradiction is just the automatic gainsaying of anything the other person says."

. Enjoy your day, but i don't doubt for a minute you that you know exactly what I'm talking about. You'd just rather launch into a personal attack than concede the points.

Last edited by normhead; 03-14-2013 at 07:14 AM.
03-14-2013, 10:36 AM   #70
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So what would the diffraction limit be on a 20mp camera?
03-14-2013, 11:59 AM   #71
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QuoteOriginally posted by VoiceOfReason Quote
So what would the diffraction limit be on a 20mp camera?
F/8.1.

BTW, f8.1 is also the effective diffraction limit for 18mp on an APS-C Canon. It will be interesting to see if the new 7D stays with 18 megapixels.
03-14-2013, 10:32 PM   #72
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QuoteOriginally posted by normhead Quote
I have no idea what you just added to the discussion. Did you forget what we're talking about?

Quoting me and saying I'm wrong isn't adding anything. It's just you enjoying the internet to launch a personal attack.Maybe you should say what you think is true.

If you don't like my assumptions, give us better assumptions, if you don't like my numbers, give us numbers you think are better. Just quoting someone and saying your wrong...that's just like the Monty Python argument Clinic. That's not argument , that's contradiction.

An argument "An argument is an intellectual process while contradiction is just the automatic gainsaying of anything the other person says."

. Enjoy your day, but i don't doubt for a minute you that you know exactly what I'm talking about. You'd just rather launch into a personal attack than concede the points.
Please show me where I attacked you personally. Thanks.


Assumptions: Let's say you want a picture at 50mm equivalent at f/1.4? How much would that cost on the Nikon? The Pentax? What would resolution be on the Nikon? The Pentax?

85mm equivalent?

35mm equivalent? F/1.4? F/2.8?

You didn't want to debate it, so I stopped responding to trolls (like any manual focus 600mm is $12k, much less a f/9 lens) as if they were reasonable arguments.

Throughout this post, I still haven't attacked you personally. I never have. I never will.

Perhaps you're taking your opinion about cameras too personally.

Last edited by ElJamoquio; 03-15-2013 at 08:04 AM.
03-15-2013, 12:53 AM   #73
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Can I ask a silly question? Oh, I just did - well, here's another one...

Is the diffraction limit independent of sensor size/pixel density?
03-15-2013, 01:52 AM   #74
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QuoteOriginally posted by Cynog Ap Brychan Quote
Can I ask a silly question? Oh, I just did - well, here's another one...

Is the diffraction limit independent of sensor size/pixel density?
It's depending on the size of the pixels. When light travels through a hole (aperture), it gets diffracted. Assuming a point shaped light source (by mathematical definition a point has a diameter of 0) you project through your lens onto the sensor, caused by diffraction the image of the point on the sensor will have a diameter >0. If the diameter of the projection is smaller than the pixelsize, the image is as sharp as it gets. If the diameter is bigger, the image gets softer. Closing the aperture results in a stronger diffraction and thus in a projection with a larger diameter. So, if you increase the pixel density (smaller pixels) you will notice diffraction at wider apertures.
Cheers,
David
03-15-2013, 04:18 AM   #75
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Thank you, David, for that extremely lucid explanation.

This would indicate that there must be an optimum pixel density trading off increased resolution for workable apertures for increasing depth of field?
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