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Messages - jrista

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1036
Landscape / Re: Deep Sky Astrophotography
« on: January 29, 2014, 10:32:06 PM »

Have you ever thought of narrow band imaging? Especially with the 3nm filters we have these days, you can even image DURING the full moon, and still get high SNR results that produce beautiful grayscale results (H-a only) or mapped images (S-II, H-a & O-III). I live under moderately light polluted skies. I was originally thinking about using an LPR, but I think now that I'm going to go all in for 3nm narrow band filters (although they are rather expensive...about $500-$700 each) so I can do more imaging from my home.

Not much you can do about cloud cover, but since you can image during the entire lunar cycle, you get a lot more cuddle time with your scope. ;)

I do image in H-alpha, but only with my CCD camera. 

I have a 5nm H-alpha filter.  Keep in mind, the 3nm H-alpha filter blocks out the N2 spectrum so your results will look a little different than most narrowband H-alpha filters which are wide enough to capture N2.

You still lose contrast when imaging during "moon-up" even with narrowband filters.  The effect just isn't as pronounced.  Because of this, I generally do not image while the Moon is up. 

It takes me about 90 minutes driving time to get to my dark site so I'm probably too picky when it comes to transparency.   I could probably double my trips if I wasn't so picky.  :(

Wade

Hmm, interesting about the N2 band. And 5nm filters are about $300 cheaper than 3nm filters are (~$600 vs. $900), so a decent savings in money.

1037
EOS Bodies / Re: Patent: Canon Curved Aperture Diaphragm
« on: January 29, 2014, 08:55:53 PM »
Jurist; With the aperture closer to the lens while the angle is the same, the area of the dispersal is much smaller which may allow better lens corrections in the first lens behind it. Just a thought.

If this is a response to me, it is jrista - Jon Rista :P

As for corrections, you might be able to correct aberrations, but there is nothing you can do to correct diffraction. Diffraction is intrinsic to electromagnetic energy, it's part of the energy field itself. It doesn't matter how close the diaphragm is to the lens, diffraction is uncorrectable. (If it WAS correctable, someone would have figured out how a LONG time ago...at the very least as a solution to better subwavelength etching at lower frequencies than the EUV we use now (which is more difficult to generate.))

1038
Third Party Manufacturers / Re: Is Sony junk....
« on: January 29, 2014, 08:37:27 PM »
I tried to copy just the summary from the 2013 annual report, its worse than I thought.  If it weren't for Sony Financial (Banking), they'd be out of business. 
Other than financial, none of the divisions are making much money, and the entertainment side along with mobile phones have monster sized losses.  This has been ongoing for some years now, and their response is to invest more money into Entertainment and hope things get better.
http://www.sony.net/SonyInfo/IR/financial/ar/2013/
 
In 2009, they lost 98.9 billion yen, in 2010 they lost 40.9 billion yen, in 2011, they lost 259.5 billion yen, in 2012, they lost 456.7 billion yen, and in 2013 they had a profit of 43 billion yen, so things seemed to be improving, but their home entertainment business is taking the company down.
 
Moody's has actually been cutting Sony's rating every year that they fail to live up to the promises they made to stockholders the previous year.  They work with Sony to understand what is happening and get promises.  They did not rate Sony as junk last year like Fitch's did, cutting them some slack.
 
Moody's is the messenger, Sony is not going to make a big News release telling stockholders that its a big risk, they keep promising and forecasting more than they can deliver.
 
Times are tough, and the companies that make the tough decisions pull thru.  There is also something to be said for companies that are able to remain focused on the long term, but for how many years can they keep struggling?
 
I certainly would like them to be successful, a healthy company can provide competition and invest in new technology that will benefit us all.


+1 Well said!

1039
Third Party Manufacturers / Re: Is Sony junk....
« on: January 29, 2014, 05:21:22 AM »
It's a damn shame in today's world where an "independent" group of people can influence the views and values of the general public world wide regards companies such as Sony, Apple, Dell, etc etc.

If this Apple in the US making crap statements such as this the Good Old non aligned US Government would rip their heads off, or at least take the opportunity to fleece them solidly.

Sony are an excellent company, producing some quite amazing products, including I feel the a7r, but they do it in competition and I feel at times, exceptionally poorly led.

Sony makes SOME good products...they make a lot of so-so products as well.

But this downgrade is a FINANCIAL thing. Regardless of the quality of Sony's products, their financials are an UTTER DISASTER. Sony has taken tens of BILLIONS out in debt. They have financed payments on old debt with new debt. They are as much a debtmonger as the EU and the US central governments. Additionally, the majority of Sony's businesses lose money, rather than make money. The most IRONIC thing about Sony is that their most profitable business sector, by a significant margin, is insurance policies in the Asian markets. :P

They absolutely DESERVE to have their rating reduced to junk. Because financially, they are junk. Because from a business standpoint, their models are junk. It's a highly, highly risky bet to buy either Sony bonds (or even stock), therefor the return to the investors who take that risk should be more richly rewarded if it pays off.

1040
Landscape / Re: Deep Sky Astrophotography
« on: January 29, 2014, 02:38:22 AM »

Very impressive. I've been looking to get that lens myself for this purpose (among others). From your description, I'm guessing it's a pretty dark site?

Thanks! 

It's a very dark site.  I measured it last Summer, and it was approaching 22.0 visual magnitudes per square arc-second.  The only problem is eastern Oregon.  It's rarely clear in the Winter.  The Summer is generally clear, but then your contending with smoke-filled skies from wildfires.  :(  When things do work out, I get about 6-8 opportunities a year during the New Moon window.

Wade

Have you ever thought of narrow band imaging? Especially with the 3nm filters we have these days, you can even image DURING the full moon, and still get high SNR results that produce beautiful grayscale results (H-a only) or mapped images (S-II, H-a & O-III). I live under moderately light polluted skies. I was originally thinking about using an LPR, but I think now that I'm going to go all in for 3nm narrow band filters (although they are rather expensive...about $500-$700 each) so I can do more imaging from my home.

Not much you can do about cloud cover, but since you can image during the entire lunar cycle, you get a lot more cuddle time with your scope. ;)

1041
EOS Bodies / Re: Canon won't offer a high megapixel body
« on: January 28, 2014, 09:34:05 PM »


You eventually reach the point of diminishing returns with sensor resolution if the lens is the limiting factor. Now, it doesn't matter how good the lens is...if you need to use f/8, you need to use f/8, and you'll never get more than 86lp/mm even with the best lens and the best sensor humanity is ever capable of producing. The only option at that point to achieve more resolution is to start taking more radical measures. Use f/4 and stack for focus. Maybe build a camera capable of always using a lens at it's fastest diffraction limited aperture, and use clever post-lens optics and software algorithms to produce whatever depth of field you need at the resolution of that maximum diffraction limited aperture. This is kind of where Lytro is pioneering something new. Their concept was consumerized, but it is possible they have the foundation of the future of ultra high resolution photography in their pockets (I don't know for sure, depends on exactly how their technology works and how applicable it is to different kinds of cameras.)
Okay, I got it. That makes sense. I think there would be no shortage of optical problems if the camera had pixels the size of the longer end of the light they're collecting! And I don't even want to imagine the S/N ratio...  I read about Lytro recently, it was fascinating! Maybe I'm being sentimental, but to me that would feel like "faking DOF"! The significance is huge, but it would feel so different if I had to use it in practice. Personally I prefer everything to happen optically that can happen optically!

With Lytro it does happen optically. There is actually a special optical array in front of the sensor. They do longer exposures, and over the duration of the exposure time, they are actually gathering information in "three" dimensions. A lytro image is not just a bunch of pixels in two dimensions, it actually contains more information that allow their software to do it's thing. It isn't just software trickery, it is a combination of optical ingenuity and software algorithms that achieve the ability to change DOF in post.

Lytro is a limited application of the concept, though. If you play with some of their examples, you'll find that there are a number of discrete options for DOF, it isn't really a continuum. Improvements on the technology could make it more effective, bring in enough information that you could indeed have more of a continuous three dimensional field that you can tweak in post. The raw data file sizes would become considerably larger, however as time continues to trudge on, processing speed and storage capacity is improving considerably (i.e. CFast 2). I don't think that the Lytro concept would ever become a mainstream, frequently used thing...it would be one of those more niche options for people who really need it.

And there are actually already some options to solve some of these problems. Not quite the way an infinite field lytro-style device does, but tilt/shift lenses can be used to great effect to control your focus. You can either constrain DOF, or expand it such that you could photograph a landscape scene at f/4 or even f/2.8 and have the entire depth of field in focus and at high resolving power. Again, though, this is a purely optical solution, and as such, you tend to pay more for it, especially if you need the capability at multiple focal lengths...so a lytro-type solution could still offer something in a cheaper package.

1042
EOS Bodies / Re: Canon won't offer a high megapixel body
« on: January 28, 2014, 08:53:54 PM »

I don't know how many times I'll have to debunk this myth. But here it goes again. First off, let's define a few things.
By all means. I did say "maybe someone else can explain it better."


Don't take it personally. Your not the first to assume the "lens outresolves sensor" myth. This won't be the last time I have to debunk it either...although I may just bookmark this page so I can copy and paste in the future. :P


...
Pushing sensor resolution to obscene levels is a lot easier than pushing lens resolving power to obscene levels. Upping sensor resolution is the far more cost effective means, and therefor the one that tends to appeal to the masses (regardless of whether they know why.)

I'm not going to even check your math, I trust it's correct! Well, that's good then. :) I'm all for higher resolution, I just had the feeling many lenses wouldn't be able to keep up. I don't mind being wrong on that one!

One additional little tidbit, I forgot to mention before. Image/output/system resolution is ultimately limited by the lowest common denominator. If your lens can only resolve 86lp/mm, it will ultimately not matter how far you push sensor resolution...you'll never resolve more detail than 85.99999999999999999999...lp/mm. System resolution has an asymptotic relationship with the resolving power of the least capable component of the system. Now, in the original example, and f/8 lens and a 5 micron pixel pitch, output resolution was 65lp/mm. Doubling sensor resolution pushed us up to 79.4lp/mm. Doubling sensor resolution again would get us much closer to 86lp/mm. Were at 1.25µm pixels now...that's pretty small. If we wanted to "double" resolution again, we would have 0.625µm, or 625nm pixels. Those are too small. Were reaching the point now where we are beginning to filter out red light.

You eventually reach the point of diminishing returns with sensor resolution if the lens is the limiting factor. Now, it doesn't matter how good the lens is...if you need to use f/8, you need to use f/8, and you'll never get more than 86lp/mm even with the best lens and the best sensor humanity is ever capable of producing. The only option at that point to achieve more resolution is to start taking more radical measures. Use f/4 and stack for focus. Maybe build a camera capable of always using a lens at it's fastest diffraction limited aperture, and use clever post-lens optics and software algorithms to produce whatever depth of field you need at the resolution of that maximum diffraction limited aperture. This is kind of where Lytro is pioneering something new. Their concept was consumerized, but it is possible they have the foundation of the future of ultra high resolution photography in their pockets (I don't know for sure, depends on exactly how their technology works and how applicable it is to different kinds of cameras.)

1043
EOS Bodies / Re: Canon won't offer a high megapixel body
« on: January 28, 2014, 07:18:27 PM »
I suspect Canon will venture into the c. 40mpx market but not for any of the reasons yet mentioned. I think they will do it because it will sell lens. You put some of the older L-series lens (let alone non-L) onto a 40+ mpx body and you will soon be screaming for better lens.

And no I can't scientifically back that statement up but I experianced first hand the IQ "old" lens could produce on the 18mpx 7D when I upgraded to that  :o

I am not sure this makes any sense. Whether you stick a 300mm ii 2.8 L lens on a 5 MP body or 22 MP body it is a great lens. Stick it on a 40 MP body and I think the same result happens.

I can see IQ being a factor for some bodies (mirrorless more than anything) but for SLR's I don't think current lenses with higher MP count sensors (40+ as you alluded to) would alter IQ.

Am I wrong here?

Increased pixel density means the sensor is putting more stress on the resolving power and aberration correction of the lens, in other words: more pixels reserved for showing each and every bit of aberration. Furthermore, the lenses have a resolution limit expressed in lpm (lines per millimeter) or lppm (line pair per millimeter). Take a 36mm wide sensor and put 8000 pixels on the wide side, and your lens will need to resolve 1.425x as many linepairs as it would for a 21 MP sensor or the image will look softer. Someone else can probably explain it better, but the basic idea is: pixels / sensor size = pixel density. The bigger the pixel density, the smaller the pixels. What comes with smaller pixels you can look up elsewhere, I don't know how to explain it without writing a thousand pages on it.

LOL

I don't know how many times I'll have to debunk this myth. But here it goes again. First off, let's define a few things.

Lens resolution: The spatial resolving power of the lens (in lp/mm)
Sensor resolution: The spatial resolving power of the sensor (in lp/mm)
System (or output or image) resolution: The measurable spatial resolution of the images produced by lens+sensor (in lp/mm)

System resolution is the result of a convolution of what the lens resolves with the spatial grid of the sensor. Both components have an intrinsic blur. This blur is generally approximated by a gaussian function, a spot of light that follows some kind of bell curve (peaked in the middle, falloff as you move away from the middle of the spot). To actually compute the REAL system resolution of a lens and sensor, you would need to know the actual PSF or Point Spread Functions of both. That kind of information is difficult to come by, and greatly complicates the math to get a small amount of additional precision. We can approximate system resolution by using this function:

Code: [Select]
ir = (1/sqrt((1/(lr*2))^2 + (1/(sr*2))^2)) / 2
Where:

ir = image resolution (output resolution, system resolution) lp/mm
lr = lens resolution lp/mm
sr = sensor resolution lp/mm

This function is a modification of a simpler function:

Code: [Select]
ib = sqrt(lb^2 + sb^2)
Where:

ib = image blur
lb = lens blur
sb = sensor blur

To convert a blur size into lp/mm, you take the reciprocal and divide by two. If we have a sensor with 5µm pixels, its spatial resolution in line pairs is:

Code: [Select]
res = (1l / 0.005mm) / 2l/lp
res = 200l/mm / 2 l/lp
res = 100lp/mm

If we invert this:

Code: [Select]
blur = 1l / (100lp/mm * 2l/lp)
blur = 1l / (200l/mm)
blur = 0.005mm

So, to directly derive the measurable spatial resolution of an output image from the spatial resolutions of a lens and a sensor, we simply combine these two formulas. First, let's assume a diffraction limited lens at f/8. Since it is diffraction limited, the lens will be exhibiting perfect behavior, so we'll be getting 86lp/mm. We have a 5µm pixel pitch in our sensor...let's just assume the sensor is monochrome for now, which means our sensor is 100lp/mm. If we run the formula:

Code: [Select]
ir = (1/sqrt((1/(lr*2))^2 + (1/(sr*2))^2)) / 2
ir = (1/sqrt((1/(86*2))^2 + (1/(100*2))^2)) / 2
ir = (1/sqrt((1/172)^2 + (1/200)^2)) / 2
ir = (1/sqrt(0.0058^2 + 0.005^2)) / 2
ir = (1/sqrt(0.000034 + 0.000025)) / 2
ir = (1/sqrt(0.000059)) / 2
ir = (1/0.0077) / 2
ir = 129.9 / 2
ir = 64.95

The image resolution with a diffraction limited f/8 lens and a 5 micron pixel pitch is 65lp/mm. That is a low resolution lens. One which most people would claim is "outresolved by the sensor". Such terminology is a misnomer...sensors don't outresolve lenses, lenses don't outresolve sensors...the two work together to produce an image...the convolution of the two produces the output resolution, the resolution of our actual images, and it is that output that we really care about.

So, let's assume we now have a diffraction limited f/4 lens. Our lens spatial resolution is now 173lp/mm. Quite a considerable improvement over our f/8 lens. It is actually double the resolving power of an f/8 lens. Same formula:

Code: [Select]
ir = (1/sqrt((1/(lr*2))^2 + (1/(sr*2))^2)) / 2
ir = (1/sqrt((1/(173*2))^2 + (1/(100*2))^2)) / 2
ir = (1/sqrt((1/346)^2 + (1/200)^2)) / 2
ir = (1/sqrt(0.0029^2 + 0.005^2)) / 2
ir = (1/sqrt(0.000008 + 0.000025)) / 2
ir = (1/sqrt(0.000033)) / 2
ir = (1/0.0057) / 2
ir = 175.4 / 2
ir = 87.7

Our image resolution with a diffraction limited f/4 lens is 87.7lp/mm. That is a 35% improvement. In this case, most people would say the "lens outresolves the sensor". But again, that is a misnomer. The two are still working together in concert to produce an image. The results of the image have improved. Now, lets say we still have our f/8 lens, and we now have a sensor with half the pixel pitch. Were using 2.5 micron pixels. Same formula:

Code: [Select]
ir = (1/sqrt((1/(lr*2))^2 + (1/(sr*2))^2)) / 2
ir = (1/sqrt((1/(86*2))^2 + (1/(200*2))^2)) / 2
ir = (1/sqrt((1/172)^2 + (1/400)^2)) / 2
ir = (1/sqrt(0.0058^2 + 0.0025^2)) / 2
ir = (1/sqrt(0.000034 + 0.000006)) / 2
ir = (1/sqrt(0.00004)) / 2
ir = (1/0.0063) / 2
ir = 158.7 / 2
ir = 79.4

Our image resolution jumps to 79.4. Well, supposedly, the sensor is "far outresolving the lens" at this point...and yet, the spatial resolution of our images has still improved considerably. By over 22%, to be exact. The fact that our sensor is capable of resolving considerably more detail than our lens does make the lens the most limiting factor...however it does NOT mean that using "the same old crappy lens" is useless on a newer, higher resolution sensor. Our results have still improved, by a meaningful amount. It is not necessary to build a new lens to take advantage of our improved sensor.

Lets take this one step farther. We are using our same f/8 lens. It isn't a great lens, it's decent, for it's generation. At f/4 it is not diffraction limited, but it performs pretty well. Let's assume it is capable of resolving 150lp/mm instead of 173lp/mm. If we run out formula again:

Code: [Select]
ir = (1/sqrt((1/(lr*2))^2 + (1/(sr*2))^2)) / 2
ir = (1/sqrt((1/(150*2))^2 + (1/(200*2))^2)) / 2
ir = (1/sqrt((1/300)^2 + (1/400)^2)) / 2
ir = (1/sqrt(0.0033^2 + 0.0025^2)) / 2
ir = (1/sqrt(0.000011 + 0.000006)) / 2
ir = (1/sqrt(0.000017)) / 2
ir = (1/0.0041) / 2
ir = 244 / 2
ir = 122

Wow. Our crappy old lens which isn't even diffraction limited at f/4, combined with our greatly improved ultra high resolution sensor, is still giving us a lot of bang for our buck! Our image resolution is up to a whopping 122lp/mm! That is an improvement of over 53% over our f/8 performance. Well, let's say we finally break down and buy a better lens, one that is diffraction limited at f/4:

Code: [Select]
ir = (1/sqrt((1/(lr*2))^2 + (1/(sr*2))^2)) / 2
ir = (1/sqrt((1/(173*2))^2 + (1/(200*2))^2)) / 2
ir = (1/sqrt((1/346)^2 + (1/400)^2)) / 2
ir = (1/sqrt(0.0029^2 + 0.0025^2)) / 2
ir = (1/sqrt(0.000008 + 0.000006)) / 2
ir = (1/sqrt(0.000014)) / 2
ir = (1/0.00374) / 2
ir = 267.4 / 2
ir = 133.7

Hmm...well, things haven't changed much. Relative to our older lens, we now have 133lp/mm. Unlike the previous jump of 53%, we have now gained a 9.5% improvement in resolving power. Ten percent improvement isn't something to shake a stick at, but our previous older lens that isn't diffraction limited at f/4 still performs remarkably well on our ultra high resolution sensor. To eek out any more performance, we would have to get a lens that was diffraction limited at a wider aperture. At apertures wider than f/4, optical aberrations begin to dominate, and achieving significantly improved results is more difficult. Additionally...you only get the improved resolving power at apertures wider than f/4...if you regularly shoot scenes at diffraction limited apertures of f/4 and smaller, then the only real way to improve the resolution of your photographs themselves is with a higher resolution sensor.

Pushing sensor resolution to obscene levels is a lot easier than pushing lens resolving power to obscene levels. Upping sensor resolution is the far more cost effective means, and therefor the one that tends to appeal to the masses (regardless of whether they know why.)

1044
Third Party Manufacturers / Re: Oh neat, a Nikon 300f2 (1981)
« on: January 28, 2014, 04:28:04 AM »
It weighs that much in part because although the front element diameter is approximately the same as a 600/4, the curvature of the element has to be greater in order to achieve a higher refractive power corresponding to half the focal length.  It also needs more correction for chromatic aberration, as well as correction for those Seidel aberrations that are f-number dependent.

The other reason why this lens is so heavy is because at the time of its design, optical glass production was not as sophisticated as it is today.  The use of anomalous dispersion glass such as fluorite crown was not quite as common back then, meaning that achieving apochromatic performance involved more design complexity.  We can also see this in the Canon EF 200/1.8L design, which uses UD glass instead of pure fluorite--the result was a very front-heavy lens.

Still another reason is simply the use of heavier materials for the barrel construction, as opposed to today's use of plastics and lightweight alloys (titanium and/or magnesium).

Canon designed on paper several optical formulas, one of which was a 200/1.4 and I believe a 280/1.8 or 300/1.8, if I recall correctly.  They appeared to use a massive amount of glass, and I suspect this was the reason why they never saw commercial production.  Nowadays, with the advent of IS and high-sensitivity digital imaging sensors, the major lens manufacturers see little if any reason to design ultrafast aperture lenses at any focal length, even though many photographers would still love to use them.  Canon hasn't optically designed an f/1.2 lens for the 135 format since the EF 50/1.2L (the EF 85/1.2L II is optically identical to its predecessor); Nikon hasn't designed anything faster than f/1.4 in decades.  Even the much-hyped 58/1.4G was not the Noct-Nikkor 58/1.2 that Nikon fans were dreaming of.  It's rather ironic, considering how some of these old designs (Canon FL/FD 55/1.2, Yashica ML 55/1.2, Canon EF 50/1.0L, the Noct-Nikkor, and Minolta Rokkor PG 58/1.2) still perform admirably well and are coveted by today's photographers for their "look."

Interesting and informative post, thank you!  Yes it's a shame these were never produced.  I don't recall the term "Seidel aberration", but perhaps I've read it...I think on the lensrentals blog.  From your take on it, it sounds like you think the current generation of f/1.2 lenses will be the last.  I hope not.  But it would make sense.  It seems like most everyone likes a 100mm f/2.8 macro lens, more than a faster aperture prime.  I'm not one of these people...

Siedel aberrations are the five most well known aberrations that most photographers talk about. So, technically, you do know about them...you just didn't know that.  ;)

The Five Siedel Aberrations:

 - Spherical Aberratin
 - Astigmatism
 - Distortion
 - Coma
 - Field Curvature

Coma and Astigmatism and possibly Field Curvature are maybe a little less known to most photographers. Certain groups would be more familiar with them. For example, coma is very well known amongst astrophotographers, and field curvature has an impact on peripheral field performance in astrophotography (the advent of flatter field optics like flat-field SCT and the very expensive (but optically phenomenal) Corrected Dall-Kirkham (CDK...just check out PlaneWave to see how expensive)). Astigmatism is also more prominent in astrophotography, as it has a non-uniform effect on star reproduction...possibly resulting in non-spherical stars, or non-spherical "slightly squashed" star diffraction glow, due do the non-uniform focus with angle.

Field curvature is probably known amongst older portrait photographers as it has a tendency to warp blurred backgrounds in a rather visible (and frustrating) way...it isn't all that common these days in good lenses. Field curvature is also quite common in DSLR optical eyepieces...I often see field curvature when I look through my viewfinder and 600mm lens, even though I know the 600mm lens has a very flat field.

1045
Landscape / Re: Deep Sky Astrophotography
« on: January 28, 2014, 03:33:32 AM »
How do you like PixInsight? I'm getting into deep sky AP now, and am in the process of buying a mount and software. I was planning to use something like Nebulosity or maybe BackyardEOS for control software, PHD for guiding, and Photoshop for processing. But Pixinsight seems pretty popular these days.
I believe PixInsight is one of the best astrophotography processing software packages out there.  I've been using it since the PixInsight LE days.  There is a steep learning curve; however, the PixInsight Forum is an awesome place to learn it and support is second to none. 

Wade

Yeah, I've heard it's a bit of an odd piece of software, but it seems it's becoming almost ubiquitous amongst astrophotographers for processing. Once I get a telescope, I'll give it a whirl.

1046
EOS Bodies / Re: Canon won't offer a high megapixel body
« on: January 28, 2014, 03:29:30 AM »
Soon Sony will have some kind of 54mp masterpiece on the market as well (using non-square pixels, to boot!)


I've missed out on this rumor, can you tell what you know so I don't have to look it up myself?


Here's the links:

http://www.sonyalpharumors.com/sr5-sony-sensor-revolution-first-non-bayer-sensors-coming-in-2015/
http://image-sensors-world.blogspot.com/2013/12/rumor-sony-to-release-non-bayer-54mp.html


Thanks.  By "large format", I assume they mean something larger than 36mm in width?


Hmm, sorry...I don't recall seeing "large format" in those rumors... Are you talking about Sony's 54mp sensor design, or something else?

As for the non-bayer array, it's still an array...don't see how it would be any more revolutionary than whatever Fuji has done.


It'll depend on the theory behind why they do whatever they do. Fuji has been toying with alternative sensor layouts for a while...but they have yet to produce anything particularly compelling. They used to have SuperCCD, which used a hexagonal array with additional white sensels to improve DR. Intriguing, and the improvement was slight...but certainly nothing on the order of what Sony produced with Exmor. Fuji brought us the X-Trans...however all that really was was an alternative means of blurring higher frequency image detail to avoid moire...and it is LESS discerning than a classic OLPF, resulting in softer high frequency detail than a normal bayer sensor.

Fuji is certainly an out of the box company, but they don't really seem to produce anything that significantly improves image quality. I think the greatest improvement they achieved with X-Trans was improved noise performance at high ISO...however the fundamental reasons why X-Trans allows better high ISO is nothing particularly novel. In fact, it is extremely well understood: averaging reduces noise, and softens detail. X-Trans inherently averages.

Both links said "it depends on what the competition does"...as in, they obviously have a good idea what Canon are up to, and want to wait to see when Canon are done with their next generation sensor.  Or else it could mean they're waiting to see if Canon releases a medium format sensor...or body.


That's the rumor bit. I don't think that part of any rumor, when a rumor has it, really has anything to do with a companies plans. Sony will do what Sony does: Produce image sensors. If there is any demand for 50mp+ sensors, Sony will probably fill it. They are without a doubt one of the top ranking CIS fabricators and providers in the world now, for an extremely extensive market that spans WELL beyond ILCs into cinematography, video, security, etc. It may well be that they produce some kind of new bayer type sensor for the MFD market first, then bring the 54mp sensor to DSLR or mirrorless. Only time will tell, but I think it will service market demand, and really have little to do with "what the competition does". Sony makes sensors...cameras (which is what were talking about here in terms of competition) are an afterthought for Sony, and I really don't think their DSLR/mirrorless segment drive what their sensor segment does. Ironically, their sensor segment could very well become Sony's most successful business...their electronics division is a black hole for money, it hasn't been profitable on over a decade, and in fact loses billions. I bet if Sony focused on sensors and insurance policies, they would be a wildly profitable company a decade from now.

1047
EOS Bodies / Re: Canon won't offer a high megapixel body
« on: January 27, 2014, 11:05:56 PM »
Soon Sony will have some kind of 54mp masterpiece on the market as well (using non-square pixels, to boot!)


I've missed out on this rumor, can you tell what you know so I don't have to look it up myself?


Here's the links:

http://www.sonyalpharumors.com/sr5-sony-sensor-revolution-first-non-bayer-sensors-coming-in-2015/
http://image-sensors-world.blogspot.com/2013/12/rumor-sony-to-release-non-bayer-54mp.html

1048
Landscape / Re: Deep Sky Astrophotography
« on: January 27, 2014, 09:18:06 PM »
To all,

Here's a wide-field image of the North America Nebula.  This was taken with a modified Canon 5D2 and a Canon 200mm f/2.0L stopped down to f/4.0.  It is an integration of 24 four-minute exposures.  It was calibrated using six dark frames, twenty biases, and twenty flats.  All calibration and processing was done in PixInsight.

Thanks for looking,

Wade

How do you like PixInsight? I'm getting into deep sky AP now, and am in the process of buying a mount and software. I was planning to use something like Nebulosity or maybe BackyardEOS for control software, PHD for guiding, and Photoshop for processing. But Pixinsight seems pretty popular these days.

1049
EOS Bodies / Re: Canon won't offer a high megapixel body
« on: January 27, 2014, 08:50:39 PM »
They will definitely, the main reason - Phase one and Hasselblad have announced 50MP Cmos sensors which are presumably made by Sony, it could be someone else like Dalsa but bets are on Sony with their 36MP tech it seems very plausible.

So the gauntlet is really down in Cmos 50MP land for canon to respond, I imagine Canon have something nearly ready by now and this may spur them to push it out quicker which would be nice.. or canon may have to buy off Sony to keep in the game.

Now MF is a different kettle of fish, and this could really help MF regain some ground back to DSLRs with quicker capture and higher iso, a much more versatile camera, though AF still is years behind basic canons & nikons.
And this could bring costs down but I wound't imagine too much.

Large format is another thing altogether so please don't try to redefine them. Having a plate camera with lens movements is the key. I've always foreseen that sensor tech will catch up and one day we will get 5x4 or at least 7x9 backs for 5x4 systems.

Hmm. That would definitely start bringing the medium format market to a new level, if they are going to use Sony sensors. I know Sony is working on a 54mp sensor with non-standard pixel shapes (either triangular or hexagonal), supposedly with similar high DR as the D800. The medium format market has long had much older sensor technology, and their sole advantage was pixel count. If they bring Sony sensors into the mix, they would again be a leap and a bound away from anything in the DSLR market.

1050
EOS Bodies / Re: Canon won't offer a high megapixel body
« on: January 27, 2014, 08:48:19 PM »
Well, that should stir things up a bit.

Here's the setup: Phase One and Hasselblad have announced 50 mp sensors for their large format (I really don't feel that we can refer to these as "medium" format anymore) cameras.

Some may see this as a sign that Canon "must" now offer a high megapixel sensor. I think just the opposite.

We have discussed to the point of nausea the idea that the larger sensor size of "full frame" cameras will always outperform APS-C. So the same principle applies here. There is simply no way that a DSLR sensor can match the performance of these large format sensors.  Scale up a 19 mp APS-C sensor and you get to just under 50 mp., so you are talking about pixel density somewhere between that of the 7D and 70D to match the new 50 mp of these large format cameras.

If Canon cannot compete on quality, they can only compete on price. So, then the question becomes, what percentage of the large format market is price sensitive? I'm guessing that few current users of either Phase One or Hasselblad would be convinced to switch based on pricing. That, in turn, leaves the sales potential only for new users. The point is we are talking about a niche, within a niche, within a niche.

Now, if Canon were to take one of their APS-C sensors and simply scale it up to full frame they might be able to keep their development costs down, but would it be low enough to turn a profit on the body? I don't know. And, you'd have to account for the extra waste that would occur with the larger sensors.

All in all, I'm thinking that a high megapixel body is becoming less and less appealing for manufacturers.

Let the flame wars begin!!!

I don't agree 100 percent, but I do mostly agree...

FF beats APS-C for IQ due to the larger pizel size..... Always has, always will....
Large format beats FF for the exact same reasons...

but I do think that in the continual quest for more pixels that we will end up with a high megapixel FF camera that has similar pixel size and IQ to that of APS-C....

I would extend what you've said a little bit. FF beats APS-C for IQ due to larger pixel size AND more pixels (in most cases, the same number of pixels on the worst case). Assuming equivalence, same framing and all that, a 5D III will not only put larger pixels on subject, but also more of them. The same goes for MFD...more pixels.

Technically speaking, MFD format sensors have actually shrunk their pixels enough that for the highest megapixel counts, their pixels are actually SMALLER on average than the 5D III. Many of the largest mp count MFD sensors have pixels in the 5µm to 6µm range. The 5D III has 6.25µm pixels.

A 50mp MFD sensor would indeed still have larger pixels, but technologically, MFD sensors are not necessarily as advanced as even a Canon sensor. They certainly aren't as advanced as the D800 sensor. For the "highest end" MFD equipment, there hasn't been a pixel size advantage for a while now. So the only REAL advantage is pixel count.

Assuming Canon can make more BETTER pixels than a 50mp MFD sensor, I think there is still a good reason for them to do it. Furthermore, Canon wouldn't really be competing with the medium format market...they would be competing with the SoNikon alliance. Nikon has the D800. Sony has the A7r. Soon Sony will have some kind of 54mp masterpiece on the market as well (using non-square pixels, to boot!) The reasons for Canon to produce a high megapixel camera have much less to do with competing with medium format, as they do with competing with their direct competitors.

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