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Messages - jrista

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1036
Photography Technique / Re: Help: lightning photography?
« on: July 18, 2014, 02:44:41 PM »
The trick with lightning photography is to expose for long enough, at a narrow aperture, and do so repetitively, that you capture live bolts. Personally, I use a simple $35 intervalometer with my 7D and 5D III, along with exposures around 10 seconds, ISO anywhere from 100 to 3200, and apertures around f/8 to f/16 (depends on the time of day/night and intensity of the flashes).  I usually program the intervalometer to take a few hundred shots, and after pointing both cameras in the direction of lightning activity, I just let em rip.

Here is a recent shot (I have more, haven't processed them all yet):



It's also possible to use lightning preflash detectors to look for the initial burst and dispersal of electrical energy that preceeds the main bolt. These will automatically trigger your camera for you once the preflash has been detected. They are pretty accurate these days, and the nice thing about them is you don't have to expose for a long period of time, which blurs the clouds.

1037
Animal Kingdom / Re: Your best animal shots!
« on: July 17, 2014, 03:19:10 PM »

1038
EOS Bodies / Re: Eos7D mk2, How EXCITED will you be if . . .?
« on: July 16, 2014, 04:15:04 PM »
I dunno. I've read the subsequent DPAF patents, and there isn't anything remotely revolutionary in there. Mostly just using different sized photodiodes for the AF part, and a means of increasing sensitivity for AF without reducing IQ. If that's all Canon's got for the 7D II, they are going to take a HUGE reputation hit...and they HAVE to know that... (If they don't, then they've totally lost touch with their customer base, and I am seriously hoping that's not the case.)

Are you suggesting that the people here are representative of Canon's customer base?  I see lots of clamoring for better IQ on forums but until the 70D, the 7D remained a strong seller.  I'd bet a 7DII with 41ish AF points and 10 fps, and a 24 MP DPAF sensor similar in IQ to the 70D, would sell quite well.

It may sell, but I think it would still hurt Canon's reputation. To date, they actually have a very good track record of listening to their customers and delivering on their customers demands. Both the 1D X and 5D III are excellent examples of that...Canon pretty much NAILED both on the head, delivering exactly what their customers wanted.

It's very clear that their customers want a better sensor in the 7D II. If Canon was to make it some big video DSLR, and completely ignore their still photography customer demands, I just think that would hurt Canon's reputation as a company that listens to their customers, and delivers meaningful improvements in IQ. As much as the 1D X and 5D III did not improve low ISO IQ to the same degree as the D800, both improved high ISO IQ considerably, and people are quite happy with them.

All I've heard, for the last several years, from people all over the net, is they want Canon to deliver better DR. Regardless of whether more DR is nearly as meaningful or important as people seem to think it is, it's still by far the single loudest demand that Canon customers, as a gigantic mob, have been demanding. I think it would be damaging to Canon's reputation to completely ignore that demand, and not only that, but completely ignore still photography demands overall and just focus in the video stuff (which is what LTRLI's posts seemed to indicate whatever rumors he read said.)

One of the things I like most about Canon is they've listened to their customers, for decades now, they have delivered new products based directly on customer feedback. I remember for years the "fewer megapixels, better pixels" demand of pro photographers who were sick of the endless megapixel race. I remember the AF system of the 5D II being one of the biggest complaints about that camera. I remember the lack of f/8 AF in anything but the 1D line being another sticking point. Canon directly addressed all of those things, and other key issues their customers had. If they ignore the sensor IQ/DR thing...they are ignoring a BIIIG issue their customers have. It doesn't matter if it matters, it doesn't matter if low ISO DR isn't as important as some of the Canon naysayers and die-hard Nikon fans insist...all that really matters is Canon's low ISO DR is most definitely at the top of a very significant number of Canon users complaint lists. They have to respond to it...some how, some way...they can't simply ignore it.

1039
Landscape / Re: jrista et al, Why Astrophotography?
« on: July 16, 2014, 04:07:02 PM »
  Boy am I feeling old.. Astrophotography was the first thing that interested me.  I bought an OM-1, had a 12.5" reflector made, and bought a Bill Schaefer mount. Used to cook my film myself.

  I am so behind times, it is amazing how technology has taken over. I got into computers when analog to digital was coming into play. Writing software for machines.

  I still have all my old equipment. Is there a way to computerize the old Schaefer mount. It has an old drive corrector that works. But, it is ancient.
 
  Been thinking about having the mirror re-coated on the reflector, and playing around with it some.

  Gary

 Scott Rosen srosen@frazmtn.com might be able to help you with your mount. His site says he has put steppers on his Schaefer.

You need more than just steppers, though. You need to track accurately enough to actually take long exposures. Even if you purchase a mount like an Atlas or ZEQ25, you still need to guide in order to be able to expose for more than about a minute or so. Just slapping steppers on a mount will get you longer than 20-30 second exposures, but not long enough to really do any kind of deep exposures that are necessary to lift detail above the noise floor (which is actually quite high on a DSLR). You would also need to jury-rig something that made those stepper motors controllable via a guider...either via ASCOM Pulse Guiding or an ST-4 guide port.

It's probably best just to buy a used lower and mount. You can find a ZEQ25 for maybe $500 used, if that if you find a good deal. A used Atlas or EQ6 can be found as low as $700 used. A Sirius/EQ5 might be found for as littel as $500-600. All of those mounts are guidable...the only real issue would be capacity, but so long as your not using larger scopes, you should be fine. You could even get an AT6RC for $400 new, or as little as $250 used, and have a real nice Ritchey-Chretein astrograph.

1040
Latest rumor out mentions that the dual pixel AF will have a radical, ground-breaking update and that that is basically what the new 7D2 sensor tech is about and not so much about still image quality improvements at all.

Another rumor from weeks back hinted that the 7D2 will introduce some new tech and that the 5D4 will get the rest (that one implied more image improvements for the 5D4). Who knows.

Got any links to these rumors? I haven't seen this on CR...

1041
EOS Bodies / Re: Eos7D mk2, How EXCITED will you be if . . .?
« on: July 16, 2014, 03:10:24 PM »
Latest rumor suggests that the big new sensor tech for 7D2 is all about a radically improved dual pixel AF that will be completely revolutionary but was also 100% silent on any talk of actual image quality improvements (an earlier rumor hinted that the next FF might be the one to focus on also improving IQ). But who knows, these sources may all be garbage.

I dunno. I've read the subsequent DPAF patents, and there isn't anything remotely revolutionary in there. Mostly just using different sized photodiodes for the AF part, and a means of increasing sensitivity for AF without reducing IQ. If that's all Canon's got for the 7D II, they are going to take a HUGE reputation hit...and they HAVE to know that... (If they don't, then they've totally lost touch with their customer base, and I am seriously hoping that's not the case.)

Sounded like they were hinting at way upping the speed and making it not focus hunt at all and perform super well for real time tracking and focusing during video.

But who knows.

That still doesn't sound revolutionary or anything like that. It's just expected evolutions on the existing DPAF. I think the patent that covers increasing sensitivity could cover a lot of that, as all PDAF is is a bunch of highly sensitive strips of pixels that can be used to detect a phase offset. Current dedicated PDAF sensors use pixels in the strips that are huge compared to current image sensor pixels...increasing the sensitivity of the photodiodes would allow DPAF to perform at a more competitive level, and by consequence become more useful for realtime focus and focus tracking during video.

Still...it just, if that's ALL Canon does with the 7D II sensor...wow. FLOP. I think Canon is smarter than that...

1042
EOS Bodies / Re: Eos7D mk2, How EXCITED will you be if . . .?
« on: July 15, 2014, 11:50:14 PM »
Latest rumor suggests that the big new sensor tech for 7D2 is all about a radically improved dual pixel AF that will be completely revolutionary but was also 100% silent on any talk of actual image quality improvements (an earlier rumor hinted that the next FF might be the one to focus on also improving IQ). But who knows, these sources may all be garbage.

I dunno. I've read the subsequent DPAF patents, and there isn't anything remotely revolutionary in there. Mostly just using different sized photodiodes for the AF part, and a means of increasing sensitivity for AF without reducing IQ. If that's all Canon's got for the 7D II, they are going to take a HUGE reputation hit...and they HAVE to know that... (If they don't, then they've totally lost touch with their customer base, and I am seriously hoping that's not the case.)

1043
Notice that the patent was filed in December of 2012. So they've had over a year and a half to work on it, plus whatever time they spent before filing. So it's possible it will be included in a 7D2 this fall.

I'd expect Canon to announce a prototype, and show off the benefits of their technology, as they have in the past, before actually using it in a product. There certainly isn't any guarantee that would happen, but it doesn't feel like the technology is ready yet. I expect more patents on the technology, and a prototype test, before we actually see a competitive layered sensor in a DSLR.
What about a P/S camera with the technology? That would be a lot safer way to introduce it.....

Possibly. I dunno, sometimes I think it's a very careful balance for companies like Canon. On the one hand, it might be cheaper (and therefor "safer") to introduce new technology at the low end. On the flip side, you then have your really high end, like the 1D X, where pros who really understand the value of the technology could actually put it to good use, and some of whom might be miffed if the technology did not show up there first.

1044
I'd expect Canon to announce a prototype, and show off the benefits of their technology, as they have in the past, before actually using it in a product. There certainly isn't any guarantee that would happen, but it doesn't feel like the technology is ready yet. I expect more patents on the technology, and a prototype test, before we actually see a competitive layered sensor in a DSLR.

Is this something you would want to actually introduce, and not trail?

I can think of few better ways Canon could produce its own 'Osbourne Effect' than to show something so different whilst still churning out a range of cameras with 'existing' technology.

Much like Craig, I've had quite a few 'rumours' sent about upcoming 'new' sensor technology, but nothing overly convincing, and nothing from anyone who's genuine (i.e not hiding behind anonymity) understanding of sensor technologies I'd rate.

Canon wouldn't be pioneering layered color sensor technology. That was done with Foveon. Canon certainly wouldn't be the "first" with a layered sensor if they released the 7D II with one.

Also, keep in mind, the very vast majority of "cutting edge" sensor technology has never made it's way into a DSLR or Mirrorless camera. Sony's Exmor technology is a pretty interesting step towards a better, more integrated sensor design, but even that is still a very far cry from the most cutting edge sensor technology. Most of the really amazing stuff is in video sensors and small form factor sensors...the ultra tiny 1/8th inch sensors that are used in phones, tablets, and other small and cheaper cameras.

In the grand scheme of things, Canon is a "little" behind, Sony is a "bit" ahead, when it comes to large form factor sensors. The technological differences are far from large, and not even remotely close to huge. The single largest differentiator is low ISO noise, which is largely due to Canon's ADC units, which are not actually part of their sensor at all...they are part of the DIGIC chips.

Both companies larger sensor technology is quite far behind the level of technology employed in smaller sensors, though. Even Sony's small 1/3" ICX CCD sensors have better technology in them than either Canon or Sony DSLR/Mirrorless sensors.

Canon could easily close the gap if they either fixed their ADC units in the Digic chips to introduce less noise, or move to a lower frequency on-sensor-die column-parallel ADC approach. All the rest of their sensor technology is actually very good. If they employed more of their noise reduction patents, they could dramatically reduce dark current noise (which can be problematic for higher ISO settings and long exposures), reduce readout frequency when a high speed readout is no necessary (lower frequency reduces noise), etc.

1045
Notice that the patent was filed in December of 2012. So they've had over a year and a half to work on it, plus whatever time they spent before filing. So it's possible it will be included in a 7D2 this fall.

I'd expect Canon to announce a prototype, and show off the benefits of their technology, as they have in the past, before actually using it in a product. There certainly isn't any guarantee that would happen, but it doesn't feel like the technology is ready yet. I expect more patents on the technology, and a prototype test, before we actually see a competitive layered sensor in a DSLR.

1046
Maybe 7D2 gets the new dual ISO instant read per pixel (ALL pixels) thing? And 5D4 that plus multi-layer sensor in late 2015?
Or maybe 7D2 gets enhanced dual pixel AF and 5D5 gets dual ISO read per pixel (NOT the ML stuff that has issues, true, dual read of each and every photosite) in late 2018  ;D.

Why dual ISO, instead of just reduced read noise? All dual ISO does is work around a read noise problem. I know Canon already has several read noise and dark current noise reducing patents, some seem quite effective. Dual ISO is a workaround that ML discovered and implemented, because current Canon cameras have high read noise.

If Canon would just reduce their read noise, then we wouldn't need dual ISO...the problem with noise and DR would be solved directly.

1047
It sounds like Canon is identifying and solving a number of issues with layered sensors. Given that, and given that their patent filings are still being published, I am not sure we'll see a layered sensor with the 7D II. The issues would need to be worked out first. It's possible all of these were filed a 18-24 months ago, and the technology is ready, but there could also be ongoing work.

I'm still waiting for a Canon patent that shows they figured out how to reduce noise and increase dynamic range in a layered sensor. I think that would make...well...everyone's day. :D

It's intriguing that Canon is working on a layered sensor, though. At the very least, it gives some hope for the cameras that come after the 7D II.
The 7D2 is obviously a mirrorless APS-H multilayer sensor camera that is tightly integrated with the Microsoft Surface tablets... :)

That would be nice...especially if it has 120 beautiful megapixels. :D

1048
Canon General / Re: Dragonfly, Powered by Canon Lenses
« on: July 14, 2014, 01:02:04 PM »
Actually, surveying for nearby supernova remnants in H-alpha might be a pretty interesting project scientifically in itself for this Dragonfly.

Yes - the problem is that we'd have to get different detectors, with much lower read noise. With narrow band filters the read noise is no longer smaller than the noise from the sky background, and the setup is no longer competitive.

Any chance you guys have some forward knowledge of larger ultra-low-noise sensors coming out? Sony's newer ICX line are pretty nice, with very low dark current, and pretty low read noise (~5e-?). But the sensors are tiny. Really tiny, as in 1/3" or maybe 1/2", which is about half the size of a KAF-8300 and about 1/5th the size of a full-frame/KAF-11002 sized sensor. Would be really nice to know that Sony has some larger sensors based on their new low-noise technology coming out... ;)

We are considering other projects to augment what we're doing now - particularly when the moon is up and our main science is on hold. We're also hoping to build a bigger array at some point in the future - with 50 lenses we'd effectively have a 400 mm f/0.4 lens, with a 1m aperture.

f/0.4 @ 1m...now that would really start to surpass, just in specs, some of the really large earth-based telescopes for sensitivity.

1049
It sounds like Canon is identifying and solving a number of issues with layered sensors. Given that, and given that their patent filings are still being published, I am not sure we'll see a layered sensor with the 7D II. The issues would need to be worked out first. It's possible all of these were filed a 18-24 months ago, and the technology is ready, but there could also be ongoing work.

I'm still waiting for a Canon patent that shows they figured out how to reduce noise and increase dynamic range in a layered sensor. I think that would make...well...everyone's day. :D

It's intriguing that Canon is working on a layered sensor, though. At the very least, it gives some hope for the cameras that come after the 7D II.


1050
Canon General / Re: Dragonfly, Powered by Canon Lenses
« on: July 12, 2014, 03:02:05 PM »
I chatted with one of the guys on this project over on the CloudyNights forums a couple months back. Back then, he said the current version of DragonFly had 8 commercially available Canon EF 400mm f/2.8 L II lenses, however that they were in the process of adding four more for a total of 12. Their ultimate goal was to get up somewhere round 20-24. To achieve that, they had to redesign the mount that holds the lenses. The original version was a squareish contraption, and I think the new approach uses something more modular, some kind of hexagonal or circular cells that can be attached to each other.

Anyway, it's a pretty cool setup, incredibly sensitive for an earth-based telescope.

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