December 20, 2014, 06:47:48 AM

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Messages - jrista

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1
EOS Bodies / Re: A Real EOS M Replacement Coming Soon? [CR1]
« on: December 19, 2014, 08:59:16 PM »
This is looking increasingly unlikely by the hour.

Why? It will lilely be announced in feb 2015.


I doubt it. Not a FF mirrorless, anyway.

2
EOS Bodies / Re: High Megapixel Camera Coming in 2015 [CR3]
« on: December 19, 2014, 12:29:37 AM »

A 50mp FF from Canon will have much better IQ than the 7D II. Pixel size is immaterial, sensor size and sensitivity (Q.E.) is what matters. On a normalized basis, such a camera should crush the 7D II in terms of IQ, because your averaging together all those tiny pixels to produce the same output resolution. That's the same as having bigger pixels.

That would be for a b/w image; in color the downsampling gives you higher chroma information density and a reduction of sampling artefacts for free. I.E. the higher resolution camera gets an additional headstart.


I'm not talking about binning, which is a hardware thing and would be limited to mono sensors.


I'm talking about averaging. I agree, it gives you all the improvements you listed, but it ALSO reduces noise. If you downsample by a factor of 2, you sample together 4 pixels into each output pixel. The noise is reduced by the SQRT(SampleCount), or a factor of 2. Downsampling a 50mp FF to the 20mp of the 7D II is roughly going to sample 2.58  pixels to produce each output pixel:


 ((26*34)/(22.4*15)) = 864/336 = 2.57 -> ~2.6x (sensor area difference)


That should reduce noise by a factor of about 1.6x. It WILL also sharpen the image and reduce artifacts. Win on every count. When IQ matters, I'll take a 50mp FF over the 7D II all day long (although until Canon fixes their low ISO read noise, I'll still take a D810. :P ). When AF performance and getting the right moment matters, I'll take the 7D II.

3
EOS Bodies / Re: Canon 7D Mark II Owners first thoughts
« on: December 18, 2014, 10:35:36 PM »
I've been shooting my 7D Mk II for about a month now, and it's spectacularly good: the image quality improvements over the 7D leap out, and (I'll post some examples tonight) at say 4000 ISO (and above), conversions from Photo Ninja are ***literally*** noiseless at 100% view.


Literally? Really?


You want to provide some visual evidence to back that up, buddy? I just love these internet anecdotes lacking any form of physical evidence whatsoever, especially when they seem to go against the laws of physics.


Can you provide a direct conversion, no additional edits, full size 100% crops no scaling at all, to demonstrate what "literally noiseless" means in your vocabulary?

I would have used the  term virtually.  I used 12500 the other day for a soccer game.  That would not have been possible on the 7d.  After post processing the images were about as good as the 7d at 800.  The noise cleans up much better than the old model.


Aye, I'd have used 'virtually' as well. To be literally noiseless would mean the image was devoid of noise, which is physically not possible. You can never have zero noise...you CAN reduce noise to the point where it may not necessarily be visible at a cursory glance, you can reduce noise to the point where you have to zoom in and scrutinize to see any. If you REALLY put some effort into it (i.e. stack 1000 frames of a still subject) you might even be able to reduce noise to the point where you cannot see it with the naked eye...however the image is still going to have noise. You can't eliminate it...only reduce it. ;P

Yep there was noise...yep there was loss of some detail.  But it was a soccer game and I was able to shoot at 1/1000 second and faster.  Next time I will target M42... A real test.


M42 is a great dynamic range test...that thing is such a beast when it comes to DR...from the brightest spots in the Trap to the dimmest outer regions it's gotta be pushing 18-19 stops or so.


I would say a better test is something with lower surface brightness. Maybe California Nebula. THAT would be a real test of the 7D II. Elephant Trunk would be another good one. There are actually probably a bunch of dim targets in Cepheus that would make a good test of the 7D II (like Iris).


I've been poking around with the math, and I am not really sure that the 7D II's low dark current is really going to be a benefit this time of year (at least, not in the northern hemisphere). The cold at night keeps the sensor cool enough that read noise dominates, and there is only a small difference in read noise with say the 7D. For any given exposure, you have about 0.6e- less read noise with the 7D II, however that only amounts to a few ADU at higher ISO. Say ISO 1600, 2.4e- 7D II vs. 3.0e- 7D.


The dark current levels of either camera at 30-40°F is low enough that you barely accumulate that much dark current noise for the kind of exposures you'll use at ISO 1600 anyway. Your going to be exposing the background sky to about 1/3rd of the histogram most of the time, 1/4 at the very lowest (but to 1/3rd is recommended for best results). At either of those levels, you are going to so totally swamp the read noise and the dark current noise on either the 7D or 7D II is going to produce the same results during cooler temperatures (winter, early spring, late fall), as were then talking about a several hundred ADU signal level. That's going to swamp read noise and dark current noise, and any amount of banding as well.

4
Third Party Manufacturers / Re: ENELOOP ????
« on: December 18, 2014, 10:14:20 PM »
Hello Surapon,

I use both the Eneloop and Imedion batteries for over 3 years on my flashes, and find both very good.
I charge them with an intelligent charger which has the functions to 'Break-in' new batteries (by charging and discharging a few times first); and to reconditioning old batteries.  Mine is the Powerex brand, but I believe there are a number of these on the market.

Regards,


Aye, I purchased a battery charger and conditioner/reconditioner. Whenever I get a new pack of Imedions, I always run them through the pretest cycle to drain/charge a few times and prime them for maximum capacity, and minimize memory issues.

Dear Friend , Mr. jrista .
I never have  "a battery charger and conditioner/reconditioner. " before for AA Battery, But I Have This "a battery charger and conditioner/reconditioner. " for my Love/ Old Canon 1DS and Love this Conditioner& Reconditioner.
Sir, What Brand name of this " a battery charger and conditioner/reconditioner. " that you recommend---And Can I order from Amazon ?
Thank you, Sir.
surapon


I'll have to see if I can find mine. My brother has a tendency to reorganize...so these days I'm always losing things. I got mine off of Amazon. It was the first one I ever purchased, so I didn't go for one of the fully featured ones that can recharge multiple battery types...I think this one just does AA and AAA, but it's simple to operate, works well, and maintains the quality of my batteries. These Imedions (which I think may actually be 2400mAh) just seem to go forever, and I don't use my flash much...so, I only haul out the recharger once every few months when one of them finally drains. :P


Anyway, if your a big rechargable battery user, I know that you can get C-cell and maybe even D-cell now as rechargables. I believe Imedion has C-cell sizes now. There are a couple real nice feature-rich chargers out there that support AAA, AA, C, D, and sometimes even odd sizes like the CRs, all in a single unit. Some can charge only four batteries, some can charge up to eight or twelve. Anyway, I'll see if I can find some links.

5
EOS Bodies / Re: High Megapixel Camera Coming in 2015 [CR3]
« on: December 18, 2014, 10:09:02 PM »
remember folks..... we are talking about a FF camera with the same pixel size as the 7D2. It will have very similar IQ to the 7D2. It will have very similar ISO performance to the 7D2.

You can't have the megapixel count of tiny pixels and the performance of large pixels. You can have one or the other... or a compromise. You can't have both. The 6D, 5D3, and 1DX will be superior in low light.

That's why I think it will be a new series, not an update of an existing series.


I disagree. The D800/D810 both demonstrate that similar-to-better IQ can be had with smaller pixels. Hell, the constant increase in megapixels in APS-C sensors for the last decade have been proving that for some time...every successive generation of APS-C sensors, each with smaller pixels, has produced better IQ than the preceeding generations, that includes Canon sensors, Nikon sensors, Sony sensors. Same goes for FF. We have observed a progressive reduction in pixel size while concurrently observing significant increases in overall image quality. So, yeah, I disagree. We CAN have both. We HAVE had both before...just not from Canon.


A 50mp FF from Canon will have much better IQ than the 7D II. Pixel size is immaterial, sensor size and sensitivity (Q.E.) is what matters. On a normalized basis, such a camera should crush the 7D II in terms of IQ, because your averaging together all those tiny pixels to produce the same output resolution. That's the same as having bigger pixels. Larger image downsampled means a reduction in noise, therefor an increase in SNR. No different really than stacking a bunch of frames together to reduce noise and increase SNR. Or simply running one of dozens of varieties of noise reduction algorithms on a single unscaled frame. It all increases SNR.


 Total light gathering capacity. I don't know how many times I've said that on these forums, or how many more times I'll have to say it...but that's all that ultimately matters for IQ (terrestrial photography...astro is a little different). :P I'd also go so far as to say that this sensor, if it has the higher Q.E., would also be superior in low light to the others at best, and no worse at worst. A loss in fill factor should be overcome by the increase in Q.E., or at worst, would simply balance things out (so high ISO performance shouldn't necessarily be worse.) A BSI design would eliminate the fill factor issue (and Canon does have some patents for BSI), and I'd say a 50mp BSI FF sensor should have BETTER high ISO IQ (since you lose significantly less light with BSI than any FSI design, regardless of pixel size.)

Assuming this 50mp behemoth has the same Q.E. (59%) as the 7D II, then it will have the same PER-PIXEL IQ (unnormalized IQ), but higher overall IMAGE IQ on a normalized basis. Same subject, same framing, same output magnification == FF 50mp kicks 7D II ass. :) At least for sensor IQ. For action, we'd still need a high frame rate and fantabulous AF system to achieve the same kind of subject freezing power as the 7D II. That's probably unlikely.

6
EOS Bodies / Re: High Megapixel Camera Coming in 2015 [CR3]
« on: December 18, 2014, 06:47:28 PM »
Any word on whether this will be Bayer or Layered?

7
Photography Technique / Re: EC - adds or subtracts light?
« on: December 18, 2014, 06:46:08 PM »
The problem isn't the math, though, even though it was wrong.


The problem the OP has is that his understanding of what EC changes is incorrect. Adjusting EC does not change the priority setting. If you are in Av and change EC, you aren't going from f/4 to f/4.5. You stay at f/4, and SHUTTER changes. Conversely, if you are in Tv and change EC, you aren't going from 1/250th to 1/320th. You stay at 1/250th, and APERTURE changes.


Exposure compensation is designed to allow you to influence the metered exposure. You have to think the right thing. You want to "compensate the metered exposure by +1/3rd stops"...if you think like that, then EC +1/3 means something, whatever it is as determined by your camera mode, has to change in order to make the exposure BRIGHTER, not dimmer. 

8
Third Party Manufacturers / Re: ENELOOP ????
« on: December 18, 2014, 06:42:21 PM »
Hello Surapon,

I use both the Eneloop and Imedion batteries for over 3 years on my flashes, and find both very good.
I charge them with an intelligent charger which has the functions to 'Break-in' new batteries (by charging and discharging a few times first); and to reconditioning old batteries.  Mine is the Powerex brand, but I believe there are a number of these on the market.

Regards,


Aye, I purchased a battery charger and conditioner/reconditioner. Whenever I get a new pack of Imedions, I always run them through the pretest cycle to drain/charge a few times and prime them for maximum capacity, and minimize memory issues.

9
Lenses / Re: Canon 100-400 ii Image Quality Review Posted at TDP
« on: December 18, 2014, 03:29:25 PM »
The midframe and corner performance of the 100-400 II with a TC is amazing:


http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=972&Camera=453&Sample=0&FLI=5&API=2&LensComp=929&CameraComp=453&SampleComp=0&FLIComp=5&APIComp=2


Compared to the Tamron 150-600 at 600 f/8, the 100-400 at 560 f/8 has WAY better midframe and corner performance. I think the Tamron might be a smidge sharper in the center, but it's not enough to give up the whole-frame performance of the 100-400, IMO.

10
Third Party Manufacturers / Re: ENELOOP ????
« on: December 18, 2014, 03:16:00 PM »
Thanks you, Sir, Dear Friend Mr. jrista
Wow, That New name for me "Imedions" and Same cost of  Eneloop too.

http://www.ebay.com/itm/PowerEx-Imedion-2400-mAh-AA-NiMH-Batteries-8-Pack-with-Case-Maha-MH-8AAI-BH-/320855295891?pt=Camera_Flash_Accessories&hash=item4ab4774793

Yes, Sir, I will try my fist 24 AA  "Imedions" with your recommend, After my Old, Old Eneloop are dead.
Thanks again,. Sir.
Have a great weekend
Surapon


You're welcome. I think you will be pretty happy with them.


One thing I should mention. The 2100mAh Imdedion batteries are a little "fat". By that, I mean they have a slightly higher diameter than most AA batteries. I don't exactly know why, but they are often a fairly tight fit. They fit into my Canon 430EX II, but they are fairly snug. I have to lightly tap to get them to shift out of the flash enough to actually pull them out. The batteries fit pretty snugly in my Logitech MX mouse as well, which is also rechargable.


This slightly fat size and snug fit might be an issue in some devices. Before you go "all in" buyin Imedion batteries, I would grab like one pack of 4, and make sure they fit into everything they need to. Eneloop batteries are also usually slightly fatter than regular disposable AA batteries, but the Imedions are just a tiiiny fraction fatter than the Eneloops.

11
Third Party Manufacturers / Re: ENELOOP ????
« on: December 18, 2014, 02:45:32 PM »
@Surapon: I LOVE your gear-laden photos. :D Great!


As for a replacement battery for your Eneloops...have you ever considered Imedion? I use Imedions myself, I have about five or six four packs worth of them, mostly AA one AAA. In my research for a good rechargable battery, the Imedions came up frequently as having good capacity (I think most of the AA ones I use are 2100mAh), with high efficiency, 1000+ recharge capacility, and stable power delivery (i.e. when used in strobes.)


I use Imedions for pretty much everything now...I've basically expunged my house of disposable batteries. About the only disposables I still have are the 9V ones in my smoke alarms. I've been able to do some pretty rapid-fire flash work at near-full brightness with my better beamer with bird photography. I can often get three or four high powered flashes in a row before it needs a little bit of recharge time. The Imedions go pretty much full bore until they finally just run out of power, then they simply stop working until recharged (I prefer that to a standard disposable AA, which slowly peters off over time requiring longer and longer recharge times in a flash.)


Anyway, there's an alternative for you. I was pretty dismayed by the 500mAh lifetime of the new Eneloop Pros myself, but since I kind of started with Imedions when I went to rechargable batteries a couple years ago, I haven't had any complaints.

12
Photography Technique / Re: EC - adds or subtracts light?
« on: December 18, 2014, 02:35:41 PM »
You are misunderstanding what exposure compensation does. When you adjust EC, your are NOT adjusting your priority setting. If your Av, that means aperture is your priority setting. YOU control Aperture, the camera controls shutter (let's assume fixed ISO for the moment.) If your Tv, that means shutter is your priority setting. YOU control Shutter, the camera controls aperture. When you compensate, your compensating the OTHER setting, not the one you control. So, it isn't f/4 +1/3 -> 4.0 + Aperture 0.3333. That's fundamentally wrong. You CHOSE f/4, the camera cannot compensate your exposure by adjusting aperture...it has to adjust shutter. So, it/s f/4 + 1/3 -> 4.0 & ShutterSpeed One Third Stop SLOWER. In other words...MORE LIGHT!


For more specificity:


EV +1/3 means ADD one-third light. This is obvious, as when you adjust EC positive, it shifts the metered exposure indicator to the left. If your shooting Av, that results in a SLOWER shutter speed; if your shooting Tv, that results in a WIDER aperture (if possible...obviously you've got a problem if your already at max ap.) If you adjust EC negative, that shifts the metered exposure indicator to the right. If your shooting Av, that results in a FASTER shutter speed (if possible, if you hit 1/4000 or 1/8000 or whatever your camera max is, you've got a problem); if your shooting Tv that results in a NARROWER aperture (if possible, if you hit min aperture, you've got a problem.)


SLOWER shutter/WIDER apeture = MORE light
FASTER shutter/NARROWER aperture = LESS light



Exposure compensation should be very easy to understand...you "compensate your exposure by adding or subtracting light." So, +1/3 means ADD a third stop light, and -1/3 means SUBTRACT a third stop light. This is easy to verify...just look at what your EC adjustments do to the automatic exposure setting (the other one, the one you are not controlling yourself).


This explanation assumes your using a priority mode on the camera. In manual mode, EC often does not do anything on many cameras. Some cameras, like Canon's 1D X, will allow you to use EC to adjust ISO, while you control both aperture and shutter. It's the same deal, though, +1/3EC means increase ISO to increase the exposure.


Sorry bub! Gotta tell the truth here. Sounds like your buying lunch! ;P

13


This is all beside the point anyway, as all it takes is ONE step, or even to stand up or start standing up, and your target could flee. Birds of the heron family in particular, for example, are extremely skittish birds. If you manage to get close enough to get a decent shot at all, then smaller pixels are going to be a bigger friend to you than getting closer. I can't count how many times just seeing my head barely rise over the top of a ridge was enough to make every heron and egret in the area fly off. Hawks are similar...they can be perfectly content with you sitting there watching them if your not moving. The moment you stand up, they'll leap off their perch and fly right over your head! :P (I've had this happen a few times.) Deer are content to get right up in your face so long as your sitting on the ground...stand up, they'll dance around and huff a few times, then wander off. Outside of wearing a ghillie suit, even in camo deer will spot me. If I stand up, they at the very least stand rigid and take notice. Start moving towards them, and they will often bolt.

It's not necessarily always as easy as taking a few steps closer to your target.

+1

I have a startling inability to walk on water so zooming with my feet rarely works.....

Obviously you need a duck boat with a blind on it. The old FF with a boat blind vs the crop on the bank debate.

Then there is the opposite question, how do the animals react when you have to get up and run away from them because you are framed to close with a crop body.


Well, that one's easy. Switch to a shorter lens, drop a TC, or use a zoom. I think a 150-600 would be an ideal pairing with a 7D II these days...and give you all the versatility you need for framing. Opening up your FoV isn't really an issue, there are options. You can also just wait for your subject to move off a bit to get better framing. There are plenty of easy ways to deal with a subject that is too close. If you really had to, you could crawl away to get farther. I've never had an animal run because I was moving away from it. ;P

14


This is all beside the point anyway, as all it takes is ONE step, or even to stand up or start standing up, and your target could flee. Birds of the heron family in particular, for example, are extremely skittish birds. If you manage to get close enough to get a decent shot at all, then smaller pixels are going to be a bigger friend to you than getting closer. I can't count how many times just seeing my head barely rise over the top of a ridge was enough to make every heron and egret in the area fly off. Hawks are similar...they can be perfectly content with you sitting there watching them if your not moving. The moment you stand up, they'll leap off their perch and fly right over your head! :P (I've had this happen a few times.) Deer are content to get right up in your face so long as your sitting on the ground...stand up, they'll dance around and huff a few times, then wander off. Outside of wearing a ghillie suit, even in camo deer will spot me. If I stand up, they at the very least stand rigid and take notice. Start moving towards them, and they will often bolt.

It's not necessarily always as easy as taking a few steps closer to your target.

+1

I have a startling inability to walk on water so zooming with my feet rarely works.....


+1


LOL, there are indeed all those physical limitations as well...water, cliffs, birds up in trees, etc. :)

15
EOS Bodies / Re: Canon 7D Mark II Owners first thoughts
« on: December 18, 2014, 02:18:26 PM »
I've been shooting my 7D Mk II for about a month now, and it's spectacularly good: the image quality improvements over the 7D leap out, and (I'll post some examples tonight) at say 4000 ISO (and above), conversions from Photo Ninja are ***literally*** noiseless at 100% view.


Literally? Really?


You want to provide some visual evidence to back that up, buddy? I just love these internet anecdotes lacking any form of physical evidence whatsoever, especially when they seem to go against the laws of physics.


Can you provide a direct conversion, no additional edits, full size 100% crops no scaling at all, to demonstrate what "literally noiseless" means in your vocabulary?

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