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Messages - jrista

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991
Photography Technique / Re: How To Remove Weird Colours
« on: January 31, 2014, 07:02:41 PM »
Guys, modern cameras have a UV filter built into them, part of the low pass filter stack (along with an IR Cut filter.) You don't need to filter UV. The light was probably your standard fluorescent blacklight. Cheap blacklights include a considerable amount of deep violet visible light. There isn't a UV cutoff issue here...the camera just picked up the deep violet visible light, which human eyes are naturally rather insensitive to. Thats all!

992
EOS Bodies / Re: Will Canon Answer the D4s? [CR2]
« on: January 31, 2014, 06:59:10 PM »
The 5D 3 really is nothing more than a 5D 2 with - at long last - a decent af-system in it. Hardly any improvement in IQ and resolution. Blatant lack of connectivity (not even wifi which canon manages to put into any 200 dollar powershot). It should really have been called 5D 2N.

The 5D 3 is really dated in every respect.

You REALLY don't know what the 5D III is, man. The 5D III was a complete and total overhaul of the 5D II. New body, better sealing, RADICALLY improved AF, improved metering, significantly bumped frame rate, improved ergonomics, etc. etc.

Use of wireless options like WiFi and GPS requires punching holes in the magnesium body...something that compromises ruggedness and sealing. So it isn't a cut and dry point there, and I would suspect that currently, more pros prefer to have the rugged body and sealing rather than the WiFi (otherwise, Canon would have stuffed a WiFi chip in it already.)

The 5D III is current and advanced in EVERY respect EXCEPT the image sensor. Get your facts strait, bub!

993
Third Party Manufacturers / Re: Is Sony junk....
« on: January 31, 2014, 12:05:23 AM »
In the past, didn't Moodys also rate General Motors as junk?
And Ford?

Aye, they did. And, both companies deserved the rating at the time! Both companies worked their ASSES off, GM even wrote down some 46 BILLION in deferred taxes, to get their ratings back up. Ford still doesn't make the greatest cars, for that matter neither does GM, however I did gain a lot of respect for Ford for not taking a government bailout. If a junk rating is deserved, it should be given. If Sony turns themselves around, restructures themselves into a better, more reliable, and most importantly profitable corporation, then their credit rating should improve. If they do not, however, their credit rating will continue to degrade.

What might happen in the future doesn't play a role in what their rating should be right now, though. And what happened to other companies that have been rated junk in the past has absolutely no bearing on what Sony should be rated right now.

994
The discussion on mirrorless is a great example of why the term slr is increasingly inappropriate. If you stuck a mirrorless mechanism in the 1dx, would it not be an slr? And, on the other hand, if you took the existing 1dx shutter mechanism and installed it into a rifle-shaped mount that had balancing weights to adjust for different lenses, would it not be an slr?

Um...the answer to both questions is: No!

The 1D X is ONLY an SLR so long as it is an SLR: Single-Lens Reflex. That implies a very specific design with rather specific construction to support the notion that the camera is a single-lens reflex camera...a camera that reflects light from a single lens to the viewfinder, allowing the operator "through the lens" framing. Take away the mirror box, and no matter what you end up with, it will never be an SLR. It'll be something else. A mirrorless is called a mirrorless, or an ilc, because it quite simply is NOT an SLR, and never will be because it can't be.

Great discussion. My personal opinion is that the slr market is severely hindered by our pre-conceived notion that a camera should look like an slr. In the future, I'd anticipate this model to be broken. Right now, some people think of it as a shutter mechanism, as the name implies. Most people think of it as the big "camera-shaped" hunk of metal and plastic that makes it look professional-ish. I don't think the shape is at all optimized, however, for taking pictures, except for the use of very small lenses. 

As others have pointed out earlier in this thread, when digital SLRs first hit the market, they took on a variety of different forms and shapes. All of those shapes failed, and the DSLR took over.

Timeless designs don't become timeless for no reason. The basic SLR design has persisted for decades. Many, just as you are now, probably proclaimed just the same things when the film SLR was first phasing into the DSLR. Obviously some companies even tried to mix things up a bit. The the SLR design is timeless. The earliest forms of SLR came onto the scene, what, in the 1920's? That is about NINETY YEARS. That's a really long time for the same basic camera design to persist.

Why does it persist, though? I mean, as early as the late 30's/early 40's SLRs had taken on the form they still have today. The general concept of an interchangeable lens camera that allowed through the lens composition was solidified by the 40's at the latest. It persists today because it is the most convenient design. Your comment above, that "the model is broken", is either entirely naive, or simply baiting. Well, sorry for taking the bait, but the SLR design is the farthest thing from being broken. It persists because it is the best form people have found to assist them in serious photography.

Modern DSLR's, particularly from Canon, are highly ergonomic. Their shape fits the hand ideally. Their weight nicely balances against the average size of DSLR lenses. Their button placement allows for optimal efficiency when changing settings during operation, allowing for procedural memory to support operation without the operator ever taking their eye away from the viewfinder! The modern DSLR body is really the pinnacle of camera body design. It persists because it's the best. Not because it is broken.

"Most people" aren't photographers. Most people don't really care about photography...they care about snapshots and visual chit-chat and instagram. The DSLR wasn't designed for most people. It was designed for photographers. So long as photographers persist, the DSLR will persist. It best solves the problem of critical photography for critical photographers. Perhaps someday someone will simply remove the mirror from the DSLR, and replace the pentaprism with an EVF...but will leave the general DSLR body design alone. I predict that the first company to do that will be the hero of the critical photographer (for a while). I predict Canon will do it best, and maintain their dominance in the market of providing critical equipment for critical photographers.

Everyone else? The snapshotters (and also the critical photographers who want something in addition to their DSLR...so basically everyone), will go with whatever is most convenient...damn the quality, damn the capabilities...they just want something that will snap photos and do instagram. Having 36mp and extensive DR doesn't mean squat to the snapshotter...they are going to obliterate all that such fancy technology has to offer anyway when they pass it through one of those (sorry, gotta say it) hideous filters for exhibition on instagram.

Sony, as the original article that the OP quoted says, makes "cool technology", but has rather bland packages that they put that cool technology into. For a critical photographer, the technology is important, but the package is more important. The A7/r is an intriguing technological advancement...sensor wise and due to the fact that it's mirrorless...but it's package kinda sucks. Everyone, even Fred Miranda, has mentioned how it doesn't really handle AF all that well (even with Zeiss lenses), and that functionally it isn't on the same playing field as Canon and Nikon. And it's small. That might be nice if the most important thing for you is portability...but it would still be better if that amazing sensor was packaged in a better body. I'd take a Canon 5D III style DSLR body with a Sony Exmor in it every time over the A7/r. (Hell, I'll still take the 5D III with it's 22.3mp Canon sensor over the A7/r!) The bigger body is one of the things that makes the 5D III so appealing...it is an ergonomic masterpiece packed full of exceptional technology in addition to the sensor, built on nearly 90 years of refinement of the best camera body known to man.

995
Third Party Manufacturers / Re: Is Sony junk....
« on: January 30, 2014, 09:23:22 PM »
Yes, "Junk" is just a colloquial term which does make for good press, however it is also used in unofficial investment nomenclature. Junk refers to non-investment grade ratings. Because Sony is now Ba1, they are no longer a "prime" investment. There are three classes of prime investments and prime credit: Triple As, the As, and the triple Bs (or, in the case of Moodys odd nomenclature, Baa{n}.) Sony is now a Ba1/BB+ rating, which takes it out of the prime investment category, and classifies it as NON-investment. In other words...STEER THE HELL CLEAR, VERY HIGH RISK! The rewards can be very great, but the chances are also very great that instead of being rewarded, you'll lose whatever you invest in non-prime (i.e. junk) rated investments.

Junk is a very appropriate term. That's why it's been used to describe this class of non-investment worthy funds for decades.

Agreed....it was a one step decrease in the rating that when from investment to "speculative."  It certainly isn't a good thing....but I bet most investors see it not as black and white...AAA or Junk....but as something that was already risky to something that has even more risk....

Sure, it isn't like it went from AAA to Junk in one move. However, dropping from Baa2 to Baa3 is less hazardous to a fund than dropping from Baa3 to Ba1. There is that additional line that is being crossed...simultaneously Sony went from being prime to being non-prime. That makes the one-step move from Baa3 to Ba1 more meaningful than the move from Baa2 to Baa3. Hence the reason it's made a rather obvious ripple in the media...it's a move that has more significance than any other prior move, even more significant than when it went from A class to B class.

996
Animal Kingdom / Re: Show your Bird Portraits
« on: January 30, 2014, 09:06:15 PM »
Not much of a shot but here's the twist.  It was shot using the 6D wifi from my computer in warmth while it's -20 C on the deck! ;)

However, I'm not too thrilled as I've been having problems keeping the connection and can't get it back.  Anyone have experience with this 6D wifi and know the typical pitfalls?  The EOS utility and live view shooting seems very clunky and I was getting pretty frustrated with the slowness of focus and the time transfering files to the computer etc.  Seems a mixed bag.

Jack

It's entirely possible the -20°C temps are the problem. When it's that cold, the batteries used in DSLRs don't function well. They often can't consistently deliver enough juice to keep the camera operating properly...the shutter will slow, mirror slap may not function properly, and radio connections become intermittent.

997
Third Party Manufacturers / Re: Is Sony junk....
« on: January 30, 2014, 07:45:37 PM »
The power of labels is funny.  Moody's didn't rate Sony as "junk."  They down graded their rating of Sony BONDS by one step, out of 23 steps.  The step just happened to drop Sony's rating from the lowest "investment" grade to the highest "speculative" grade.  There are still 10 steps below Sony's current "Ba1" grade. 

The primary functions of these ratings are to given investors looking to buy bonds a sense of the risk that the investor may be taking on that the company (Sony) won't be able to pay back that bond and to help set the rate of return/yield/interest that will attract investors.  This is as much about comparisons as absolutes so that investors know that Sony bonds are about the same risk as bonds from company XX or more risky than company YY. 

And speculate about Moody's all you want...but, given Sony's debt and recent financial losses, would you buy Sony debt for a very low interest rate?  Or is the chance that they may default/go into bankruptcy enough that you may want more of a return on your investment to justify the risk.  That is all this is. 

"Junk" is just a label that makes for good press.

Yes, "Junk" is just a colloquial term which does make for good press, however it is also used in unofficial investment nomenclature. Junk refers to non-investment grade ratings. Because Sony is now Ba1, they are no longer a "prime" investment. There are three classes of prime investments and prime credit: Triple As, the As, and the triple Bs (or, in the case of Moodys odd nomenclature, Baa{n}.) Sony is now a Ba1/BB+ rating, which takes it out of the prime investment category, and classifies it as NON-investment. In other words...STEER THE HELL CLEAR, VERY HIGH RISK! The rewards can be very great, but the chances are also very great that instead of being rewarded, you'll lose whatever you invest in non-prime (i.e. junk) rated investments.

Junk is a very appropriate term. That's why it's been used to describe this class of non-investment worthy funds for decades.

998
Animal Kingdom / Re: Show your Bird Portraits
« on: January 30, 2014, 04:37:29 AM »
Snow day today in NC, so I sat in my blind to shoot some birdies near my suet feeder. 5DMKIII, 600 II + 1.4X III, better beamer flash fill (-1 & 2/3 stops), AV at f8, ISO 1250, shutter speeds 1/800-1/2000, rear focus.

Beautiful shots, Vern! You have a wonderful diversity of birds where you live, especially with the Cardinals. (They only live in about the eastern half of the country.)

999
Landscape / Re: Deep Sky Astrophotography
« on: January 30, 2014, 04:32:02 AM »

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.

I would recommend getting the H-alpha in 5nm, S2 in 3nm, and O3 in 3nm.  The only drawback to 3nm is if you have a fast system (i.e. f/3 or faster).  They become less efficient and your almost better off getting all 5nm.

Wade

Yeah, I read a bit about the f/3 issue on Astrodon's site. I am actually planning to use my 600mm f/4 lens as a fast APO refractor. Probably with an SBIG STF-8300m in the long run, with the filter ring accessory. Is f/4 fast enough to cause problems?

1000
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.

1001
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.))

1002
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!

1003
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.

1004
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. ;)

1005
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.

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