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Topics - jrista

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Animal Kingdom / The 1200mm Sharpness Test
« on: December 07, 2014, 01:05:54 AM »
I started putting together a new bird setup in my back yard a little while back. I haven't had much of a chance to use it yet, but, I did to some shooting at 1200mm f/8+ on the 5D III. At first I was a little dismayed by the sharpness, thinking the 2x TC was really costing me too much detail. However a little bit of tweaking took care of that.

Not the greatest of shots...that day had poor lighting (and it was backlighting), but here is an example of the original shot:

And here is the shot after sharpening (and a little bit of other processing):

Here is a closeup of the original:

And again after sharpening:

The softness present in the original image is pretty much gone after the sharpening. And that's for 1200mm f/10 ISO 1600.

Here is a 100% crop. The lighting, as I said, was horrible...the highlights along the back top of the birds head pushed down the rest of the exposure, and I was already at ISO 1600. So the noise in the background looks bad (I just used LR to denoise, and there is a specific reason why the noise in the background looks so bad...see below...I have other tools that should do a better job, but I haven't bothered yet):

I know a lot of photographers worry about using the 2x TC III on their lenses (one that can take it and still AF, anyway). I don't use it all that often myself, but after seeing how well the detail in this image sharpened up, I am pretty convinced, at least within around 60-80 feet or so, use of the 2x TC need not be accompanied by softer images. It should be noted that I did have to use a fairly high sharpening radius, 2.3 in this case. I normally use much lower radii, 1.0-1.3 tops most of the time. Some times I've even reduced the radius. To fully eliminate the softening, a larger radius was required. One thing that should be noted...the use of a larger radius has a negative effect on makes noise harder to remove, and sometimes it exhibits artifacts. I think in the long run, for images like this, I'll convert to TIFF, denoise first, then sharpen, which should avoid most of that problem.


It seems it's primarily intended for cinema...but still...14 stops at ISO 100, 21 stops at ISO 5120, and the thing doesn't drop below 10 stops until an insane ISO 655,360!?!?

Frickin nuts man...when the hell is Canon going to get into the sensor game?!!?!?!?!?! AAARRRRG!! :o :o :o

Bummer they are using a 16bit ADC...I guess with S-LOG they are basically shifting the shadow tones up in-camera, so in some ways they could be benefiting from that 21 stops...which is fine for video. For stills, they should really be using a 20-bit ADC. I guess we'll see if they stick this sensor in a stills body or not, but if they do...I certainly hope it would use 20-bit ADC.

So...I was browsing around imaging resource, checking out the NX1 preview. I started comparing the sample images with the 7D II. I was blown away by the quality of the NX1 up through ISO 6400, and even 12800 for that matter. You can clearly tell the 7D II is noisier. So, I decided to compare with the 5D III.

All I can say is...WOW. I'm hooked on the NX1!! :P I think it may be my new high speed birding camera some time next year, assuming the lenses pan out. I think I'd get this before I got an A7r I am well and truly impressed.




The NX1 has more megapixels than even the 5D III, and the noise is just about as clean. The NX1 definitely has lower chroma noise. The links above are NON-normalized...I intend to normalize once I get home, and once normalized, I expect the NX1 may even TOP (!!) the 5D III for ISO6400 IQ. Now that would be a thing of APS-C with BETTER IQ than an FF?? Noo! Say it ain't so! :P

The 5D III does seem sharper...not sure why. It almost seems as though the lens is not fully focused with the NX1...but, that kind of seems to be par for the course for IR. I've never felt they get the best example images.

Another source of examples, although not comparisons, is Luminous Landscapes review of the NX1:

The bookshelf examples near the bottom are just mindblowing. The IQ up through ISO 6400 is just amazing. It starts to fall apart after that, but still...I am extremely impressed by the IQ from this BSI ISOCELL sensor at ISO 6400.

I think Sony has a real competitor. Samsung is another electronics powerhouse...I am very curious to see how they do in the marketplace. I love that they have produced a DSLR-style mirrorless body, instead of some micro-cramped body like the Sony A7 series. I think it is much more along the lines of what I have been looking for, and in comparison to the 7D seems the NX1 tops it in just about every category except lens selection (and, if the adapters work well, that may not even be an issue...and certainly won't be an issue for terribly long, as Samsung is already working on some nice big white supertelephoto lenses.)

EOS Bodies / Canon 7D Mark II - Finally using Canon's newer fab?
« on: November 09, 2014, 01:28:26 PM »
So, I was poking around on, and noticed the 7D II was listed. I clicked into it, and saw this:

A larger format Canon sensor with 59% Q.E.!! I've only seen that on their small sensors, the ones that come from their other fab. It hasn't topped 60% yet, but overall it's quite a jump from the 40% range that the vast majority of Canon's prior DSLRs fell into.

Given the fact that DR hasn't improved despite the increase in Q.E., I am more certain than ever that Canon's problem is in their ADC units. I think this correlates well with the fact that as the readout frequency increases, read noise increases (1D X, 70D, 7D II...all have higher read noise.) That gives me hope that if Canon does move in the future to an on-die hyper-parallel readout system that operates at a lower frequency, that they should be able to reduce their read noise.

Read noise aside, seeing a Canon APS-C sensor with 59% Q.E. is a good sign. Certainly nothing conclusive, however it does indicate that they very likely have move at least 7D II sensor production to a better fab. It's a stepping stone, and hopefully one of very few to get to a better place on the sensor technology front. Here's to hoping the 5D IV sensor tops 60% Q.E. (and gets to around 65%...that would be another nice jump), and also gets an on-die readout system.

Third Party Manufacturers / iPhone 6 gets an Exmor
« on: September 29, 2014, 02:24:16 PM »
I found this the other day:

Looks like even iPhone has moved to Exmor. Excerpt form Chipworks (their page doesn't seem to be loading at the moment):

"The iPhone 6 Plus iSight camera chip is housed in a camera module measuring 10.6 mm x 9.3 mm x 5.6 mm thick. Fabricated by Sony, the iSight camera chip is a stacked (Exmor RS), back-illuminated CMOS image sensor (CIS) featuring 1.5 µm generation pixels (introduced for the iPhone 5s). The die size is 4.8 mm x 6.1 mm (29.3 mm2). The phase pixel pairs have all been implemented in the green channel and cover the majority of the active pixel array."

"Our speculation of Sony winning the FaceTime sockets, though, turned out to be correct. We’ve just confirmed the iPhone 6 Plus FaceTime camera is a stacked Sony CIS and will provide more details in a future update."

I received my A7r rental from LensRentals today. I've been working, but I took a few minutes to snap some quick shots of my living room, with the goal of preserving the highlights of the bright sunlit outdoors in the front windows. To do that, I had to underexpose the foreground well below the levels that they appeared it my eyes.

I did not try to make any explicit exposure choices here. The goal was simply to expose for the highlights. These were shot from the hip, no tripod, no real planning. The goal was just to create a couple exposures with highlight preservation in mind, and see how the shadows handled some major pushing. I'll leave it up to each person to draw their own conclusions. I have provided a link to the raw files, so you can all download them, play with them yourself, and verify (or refute, if you prefer) the various claims made about DR.

Here are the original exposures:

Canon 5D III

Sony A7r

Here are the exposures lifted to generally mirror what the room looked like to my bare eyes (+4EV, -100 Highlights):

Canon 5D III

Sony A7r

Just to see how far I could push things, here a couple more versions, not particularly "realistic", but still a good demonstration of what's possible and how the raw data reacts. No interpretation of the data needed here...5D III totally falls apart. A7r...noisy...but manageable.

Maximum push (+5EV, -100 Highlights, -100 Whites, +50 Shadows):

Canon 5D III

Sony A7r

Here are full size versions of the +4 stop pushed examples (zoom in on PhotoBucket for full size):

Canon 5D III

Sony A7r

Here are full size versions of the +5 stop pushed examples (zoom in on PhotoBucket for full size):

Canon 5D III

Sony A7r


ETTR? Yup. Too much. On both cameras.

You can download the raw files here:

Finally got a chance to process one of the sets of images I got with the A7r and 5D III. This particular set of images I did not really expect to show any difference, however I think the subtleties and small push here might actually be best. I saw this rock with a patchwork of different kinds of mosses, frames in the spotty sunlight shining through some pine trees. I thought the light and shadow made for a decent example of DR.

Here are the original shots:

Canon 5D III

Sony A7r

Here are the shots processed to bring up the shadows:

Canon 5D III (+2 EV, -80 Highlights, +100 Shadows)

Sony A7r (+2 EV, -85 Highlights, +100 Shadows, +35 Contrast)

Here is a quick close-up comparison of the two key shadow areas after the 2-stop push.

Raw files pending.


I just found it interesting...this page used to be completely dominated by Canon DSLRs. Earlier in the year/late last year, there were only a couple Nikon cameras on the list, and all of them were below 10th place. Today, I just thought I'd take another gander:

Canon still holds the top spot, with the T3i...however (at the time of writing this...seems the report is updated hourly, so who knows what it will be by the time anyone reads this):

#2: D3300
#4: D5300 Kit Option
#7: D7100
#9: D810
#10: D3100
#15: D5300 Kit Option
#17: D5200

That is seven DSLRs on that list that are now Nikon. Plus a Pentax. Of the cameras on the list, all of the Nikon's except for one held their position or GAINED. ONE Nikon fell. Of the cameras on the list, it was split 50/50 between which FELL and which gained or held their position.

This has been a staple ranking for those who tout the market share argument. I think, in general, THIS page is one of the key pages that fuels the market share argument. In addition, so does this page:

Where the top two spots are held by Nikon kits now. It should also be pointed out that Nikon and Sony cameras hold the top spot on all the Digital Camera best sellers listings. I don't think that a page that updates hourly is honestly a good gauge of which specific camera is best...however I do believe that the consistency of brands on these pages over time is an indication of market trends. These pages used to be dominated by Canon on a regular, they seem to be much more diverse. Regardless of who has what rankings, the greater diversity is very intriguing to me.

I started looking at these pages to see what the current state of "the market", in this case, let's just say the whole damn digital camera market, really was. In my additional searches...I have actually not found any recent market share data that's been aggregated into something easily comparable between brands. There are lots of reports, up supposedly through 2012, and some reports published in 2013, however from an actual real data standpoint, most seem to reference data up through 2010 and maybe 2011. I have not actually found any global sales reports, for the DSLR market specifically, but even the digital camera market in general, that was completely through 2012, and nothing at all for 2013. I found some reports that speak about just the Japanese or Asian markets, however the demographics there, and the cameras sold, don't seem to jive with the rest of the world (more mirrorless, for example).

So...the whole market share argument...I'm just curious, honestly curious, where it comes from. When I look around, I see that market share up through 2010 was indeed dominated by Canon. It was still controlled by Canon in 2011, however Sony and Nikon apparently closed the gap. Since then...the most critical years...2012, 2013, 2014...there doesn't actually seem to be any concrete data about the real state of the market. Only bits and pieces of disparate data that aren't directly comparable. Who is dominant, who is selling the most...and of what kind of cameras? How has market share shifted, if it's shifted at all? Which camera types are most popular, and what alternatives are REALLY cutting into what markets and where?

Based on the current Amazon Digital Camera best sellers rankings...Canon, which I do remember held the top spots in pretty much every category...only seems to hold the top spot in ONE category now, and Nikon and Sony cameras are much more prevalent in those categories as well. Overall, those pages contain a greater diversity of brands, and the very strong dominance Canon cameras once held seems to have wavered.

Landscape / Within Forests
« on: September 01, 2014, 05:30:39 PM »
I noticed there wasn't a thread dedicated to forest landscapes. The purpose of this thread is to show off your photos where your right there, in a forest, jungle, rainforest, etc. Aspens, Redwoods, Pines...if your surrounded by trees of any kind, it's a forest. ;)

Forest Boke

5D III and 50mm f/1.4

For those of you who know me, you know I started doing deep sky astrophotography this February. I know a lot of you have expressed interest in the hobby, so I thought I'd share my latest setup. I've learned a lot in the last seven months, including which way is best for setting up a tracking mount for use with DSLR equipment (particularly with Canon's big L-series telephotos, which double as superb "astrograph" telescopes.)

My first attempt, as far as mounting equipment went, was to purchase ADM Accessories' "Dual Side-by-Side Saddle". This is couple pieces of solid, machined metal configured in such a way that it will allow two pieces of equipment, such as a telescope and a guidescope, to be set up side by side on a tracking mount. It looks something like this:

While this got me started, it ultimately turned out to be heavy, difficult to balance, and overall just clunky. It's a better option if you plan to run two identical scopes side-by-side (which some astrophotographers do...they will run two identical setups side by side to either gather sub light frames (just 'subs' for short) at twice the rate, or they will set up each scope and imager with a different set of filters (such as RGB on one side, and Narrow Band on the other) for highly detailed, colorful imaging with mono CCD cameras.

I recently found some better parts, ones that gave me the option of creating a much tighter, much lighter, more compact, easier to balance and more stable means of mounting my lens to my tracking mount. This setup looks like the following:

The equipment in the pictures is the Canon 5D III, Canon EF 600mm f/4 L II (with RealTree4 LensCoat, no hood),  Orion Atlas EQ-G equatorial tracking mount, Orion 50mm Mini Gidescope, QHY5L-II Mono guide and planetary imager (uses a Aptina MT9M034 CMOS sensor, extremely high 74% Q.E.), an ADM Accessories 15" D-type Universal Dovetail, and a couple of Cradle-type Clamshell Scope Rings from ScopeStuff.

I also used various bits of super cheap hardware from Lowes and/or Home Depot, including large washers, and some long hex-cap 1/4-20 screws to level out the center axis of the scope rings, and attach them to the dovetail. Grand total cost here was maybe ten bucks.

The total cost of these items (excluding the Canon pieces) was less than $2000 (maybe a little more if you don't find the Atlas on sale), which in the grand scheme of things is extremely cheap for astrophotograpy gear. To really get any better than this, you need to spend more than $2000 on just the mount (and more like $8000 to $25,000), you need to spend several thousand on a good astrograph (a good refracting telescope, one that doesn't even have as large an aperture as the 600/4, is going to run you several thousand at least, and for something with a 130-150mm aperture like the 600/4 is going to run you anywhere from $10,000 to $15,000 anyway; a good RC or CDK astrograph is going to cost you at east a few thousand, if you get something from Astro-Tech...and as much as twenty to eighty thousand for a 12-24" RCOS or PlaneWave).

If you already have Canon equipment, such as a DSLR and say a 200, 300, or 400mm lens (doesn't necessarily have to be a big L-series telephoto...just any long lens will usually do), then for $2000 or less, you could get yourself a pretty accurate tracking mount and all the other necessary equipment to reliably mount your camera and lens to that mount, with a high quality guiding setup (Orion 50mm mini guidescope and QHY5L-II CMOS camera), which, when set up and handled properly, is good enough for 600 second (10 minute) exposures (which is enough for f/8 telescopes, and more than enough for lenses with f/6.3 or faster apertures.

Now, I personally HIGHLY recommend the Orion Atlas mount, or the SkyWatcher EQ6 (which is the same thing, even manufactured by the same company in China, just a different company). The key benefit with these mounts is the ability to use EQMOD with them, which is very powerful, flexible software that runs on a computer (laptop or windows tablet) and replaces the hand controller. The use of an Atlas/EQ6 is not a requirement, however. If you are not using a large Canon L-series telephoto (the 300, 400, 500, 600, or 800), then you do not necessarily need the capacity this mount has to offer. You could get something like the iOptron ZEQ25, which runs around $800 ($500 cheaper than the Atlas...which in and of itself is enough to cover the QHY5L-II and Orion 50mm Mini Guidescope). The ZEQ25 is a capable mount, it just doesn't have the carrying capacity nor the compatibility with EQMOD. It is more than enough for a DSLR with a smaller telephoto lens up to 400-500mm (say a Canon 100-400, 400mm f/5.6 prime, or maybe a Sigma lens that goes up to 500mm...possibly even the 150-600.)

So, if you really want to get started with deep sky/planetary/lunar/solar astrophotography, you can do so for less than $1500. That may sound like a lot, and for some of you it may be...but it's actually ludicrously cheap as far as astrophotography equipment goes. If you spend the money, don't regret it. Astrophotography is a complex hobby, and certainly not for everyone...but for those of you who are really interested in getting into it, it is really money VERY well spent.

Well, I said for a long time that once I got a 5D III, I'd do some comparison shots. I've long held the opinion that crop sensor cameras, like the 7D, do have value in certain circumstances. The most significant use case where a camera like the 7D really shows it's edge over full frame cameras is in reach-limited situations. A reach limited situation is one in which you cannot get physically closer to your subject, and your subject does not fill the frame. The likely case is that you are using your longest lens, and will likely crop in post.

In the past, others have made the argument that a camera like the 5D III or 1D X has so much more image quality than a camera like the 7D that the 7D could never compare. The argument was made that an upsampled 5D III or 1D X image (or even, for that matter, D800/E, D600, etc. image) would be just as good.

I'd like to prove my case. I've taken the most reach-limited scenario possible...photographing the moon, with a 1200mm lens (Canon EF 600mm f/4 L II w/ Canon EF 2x TC III). I used a Canon EOS 7D and a Canon EOS 5D Mark III for imaging. The lens and camera were attached to an Orion Atlas EQ-G equatorial tracking mount, operating in Lunar tracking mode, to minimize any other factors that might affect image quality. Seeing (atmospheric turbulence measure) was average.

Above is a GIF image of the 7D and 5D III images scaled to the same size, overlaid directly on top of each other using Photoshop's layer difference blending mode for best possible alignment. Both images were created exactly the same way, by initially focusing with BackyardEOS' focus module for optimum focus (BYEOS is like having a 2560x1600 live view's awesome!) The image exposures for both cameras are 1/100s f/8 ISO 200. Five images for both cameras were taken, the best frame from each set was chosen for comparison. Both images were maximally cropped simply by choosing 1:1 in Lightroom. Both images had identical processing applied in Lightroom (one image was processed, it's settings were copied and pasted onto the other.) Both images were initially scaled to approximately 1/4 their original size (770x770 pixels, to be exact).

The 5D III image was then layered onto the 7D image, and upsampled in Photoshop by a scale factor of exactly 161.32359522807342533660887502944%. This scale factor was derived by computing the sensor diagonals of both cameras:

Code: [Select]
ffDiag = SQRT(36^2 + 24^2) = 43.266615305567871517430655209646
apscDiag = SQRT(22.3^2 + 14.9^2) = 26.819768828235637870277777227866

Then dividing the FF diagonal over the APS-C diagonal:

Code: [Select]
43.266615305567871517430655209646/26.819768828235637870277777227866 = 1.6132359522807342533660887502944x
Then finally multiplying by 100% (to get a relative scale factor that I could directly apply with Photoshop's layer scaling tool.)

I believe the GIF above speaks for itself. The larger pixel size of the 5D III clearly does not resolve as much detail as the 7D does. Not only is the 7D image sharper, but there is a significant increase in fine details, small craters, nuances of color, etc. Here is another GIF, this time the images are only 1/2 original size (any larger, and the effects of seeing diminish any real benefit...I've had days where seeing is excellent, and more detail can be resolved, but sadly tonight was not one of those days):

The 7D's smaller pixels, despite being a generation prior to the 5D III's, are still resolving more detail, especially fine edges to crater rims (some of which don't even show up at all in the FF image), and are extracting a finer and more nuanced level of color. Many smaller craters, especially those that are inside larger craters, as well as the central mounds of many craters, are either difficult to make out or simply don't appear in the 5D III image, where as they show up clearly in the 7D image.

A common reach-limited use case is bird photography. Similar to the moon, it can be difficult to get close to and fully extract all the detail from a small songbird, shorebirds, and shy waders or waterfowl. One either needs a significantly longer lens on the full frame (I am still experimenting with the 5D III, but I'll probably be using 840mm and 1200mm a lot more than 600mm), or you need the skill to get much closer to your subjects, in order to fully take advantage of the benefits the larger frame has to offer.

Anyway, there you have it. The 5D III is an excellent camera, and when you have the option of framing identically (i.e. filling the frame with your subject), the larger frame trounces the 7D in terms of image quality. It gathers 2.6002949408613476991603214253469x more light:

Code: [Select]
(36 * 24) / (22.3 * 14.9) = 864 / 332.27 =  2.6002949408613476991603214253469
With more than two and a half times more light, it's two and a half times better. Like using two and a half stops lower ISO on the cropped sensor. However if you don't have the option of either getting closer to your subject, or using a super long lens (not everyone has the option of spending $13,800 ($12,800+$500+$500) on a 600mm f/4 II and both of Canon's Mark III TCs), then there is no question that a camera like the 7D, or currently the better option the 70D, is going to give you the option of creating more detailed photos.


Ok, here are a few updates, as per requested.

The first image here is the 7D and 5D III at "native" size. To further clarify my procedure from above. These images were "cropped", however they were cropped such that 100% of the sensor height was used. The only parts of the image that were discarded were the empty black sky areas to the left and right of the moon. That means, from a technical standpoint, these are 1:1 crops. They are then downsampled, but since I used 100% of the sensor height, these crops are directly indicative of the relative size difference of the moon in both frames.

You'll notice the 5D III image is sharp. Both images were sharp, or at least, as sharp as I could get them. I basically used a live view method of focusing, however one that is much more advanced. I used the program BackyardEOS, which is an astrophotography imaging tool that is specifically designed for Canon EOS cameras (which are endemic in the astrophotography world for budget imagers...the T3, T3i, 60Da and 6D are pretty much the top cameras you'll find in astrophotographers kits...those that don't use dedicated astrophotography CCDs.)

BYEOS has a brilliant frame and focus wizard. It takes the live view feed from the camera, and renders it on a computer screen. I can maximize the program and basically get 2560x1600 live view (minus a bit program panels and border).

I use these tools to focus:

I use coarse and medium to get focus close, then step with fine. The fine focusing arrows are extremely fine...they are designed to focus stars, so they move the focus group in the lens by the smallest possible amount. I spent about five minutes with these tools with both cameras to find the best focus possible. It isn't as easy as it don't just end up with a crisp, sharp moon. The moon, at that size, looks more like it was dropped into a vat of boiling water, and every few seconds you have a moment where the "water" (atmospheric turbulence or "seeing") clears, and in that moment you have to gauge whether to focus forward or back to get it better.

So, the images are focused as best as I could get them.

The next image here is a noise comparison. It has three frames...a 7D crop that is unscaled, a 5D III crop that is unscaled, and a 7D crop that mirrors the 5D III crop that IS scaled. The 7D, at native size, definitely has more noise. It also looks almost as soft as the 5D III image.

When the 7D image is downsampled to the same size as the 5D III image...any advantage the 5D III had in terms of noise disappears. The 7D image clears up a bit, and appears a little sharper. Fine details pop a little bit more than they do with the 5D III.

Why? Because the moon covered the same absolute sensor area. There is a difference in pixel count between the two images, but overall, both sensors gathered exactly the same amount of light! That's the key there. There is no advantage to a larger sensor if you are not utilizing that increase in sensor area. If your using the same exact absolute sensor area between both cameras...there is no difference. If the 7D had 6.25µm pixels, then the two cameras, in this kind of situation, would perform IDENTICALLY.

In a reach-limited scenario, you want smaller pixels. It really doesn't matter if your using a full frame sensor, a medium format sensor, a micro 4/3rds sensor, or an APS-C sensor. If the pixels are all the same size, and you put the same number of pixels on your subject...assuming all four of those sensors use the same technology, there is literally no difference. That is usually not the case, though. Smaller sensors generally tend to use smaller pixels. The 7D still has smaller pixels than the D800 and D810. Smaller pixels trump bigger pixels when you are reach-limited.

Just a little rant. I was going through some of the gallery forums and...I'm appalled. More than half the thumbnails are ULTRA TINY!!! Worse, you have to click each one, which opens up in a new window, to see it full size. Which you have to close, to click another one. Incredibly tedious. What's with that?!

  :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'(

Those are photography forums, and it was really quite convenient to just be able to see all the images uploaded at the full width of the forum. I never had to click anything to see what people were uploading.

I officially request the old image attachments viewing mode be brought back, as there is no way I'm going to click fifty times to view the images attached every time I go through the gallery forums. That's just...asking way too much.  :o

Landscape / Total Lunar Eclipse - #1 of 4 - April 2014
« on: April 14, 2014, 11:54:29 PM »
There are FOUR total lunar eclipses occurring over the next two years. Tonight is the first of the four. It starts at 1:58pm ET, 11:58 MT, and 10:58 PT. If you are planning on photographing the first lunar eclipse this year, share your photos here!

I'm aiming to get a full sequence of the entire eclipse, from the first penumbral dimming through totality and ending at the point the moon moves out of the penumbra (for me, that's from 11:58pm through 3:30am.)

For more details, see here:
For exposure tips, see here:

Landscape / Deep Sky Astrophotography
« on: April 08, 2014, 12:17:35 AM »
The other thread ended up with a bit too much discussion on the topic of astrophotography and the related gear. Figured a new, clean one, dedicated just to the imagery, would be good.

Please, feel free to share your own images as well! (If you already shared some in the old thread, maybe re-share them here, hopefully we can keep this topic free of astrophotography gear and technique related discussion, and just keep it on the images.)

Here are some of my images, produced with some dedicated astrophotography equipment (german equatorial tracking mount, or GEM, guiding telescope and camera, etc.) All of these were created from mid Feb. 2014 through the end of March. 2014.

Star Clusters
The Pleiades (Seven Sisters), in Taurus:

Original Attempt

Second Attempt (deeper exposures, softer detail due to tracking issues)

M35 and NGC2158, in Gemini

Horse Head and Flame Nebulas, In Orion:

Orion Nebula (M42 & M43) and Running Man, in Orion:

Rosette Nebula, in Monoceros (Unicorn):

Original Processing

Reprocessed in PixInsight

M101 (Pinwheel Galaxy), in Ursa Major:

M81, M82 and NGC3077, in Ursa Major:

M51, in Canes Venatici:

Leo Triplet (NGC3628, M65, M66) & NGC3593, in Leo:

Reviews / 6D Noise Levels and Comparison Tests
« on: February 28, 2014, 09:25:33 PM »
Someone from CloudyNights forum performed some useful tests of the 6D noise levels at different temperatures at astrophotography exposure lengths. Very interesting stuff, for those who are interested. You can find the images here at the original thread:

One of the very interesting things is you can see how much temperature affects read noise levels. The images are taken at +21°C, +7°C, and -7°C, with exposure times of 300 seconds.

EOS Bodies / Canon Dual-Scale Column-Parallel ADC Patent
« on: December 11, 2013, 02:33:01 AM »
It's been a while since I last scanned through Image Sensors World blog. Around the beginning of August, as a matter of fact. Since that time, they noted that Canon filed for a "Dual Scale" CPADC patent:

If I understand the diagrams and the patent correctly, and I am no CMOS engineer, it sounds like Canon is maybe following ML's lead in using a dual gain (i.e. Dual ISO) approach to achieving higher dynamic range. Given how long it takes to produce technology viable enough for a patent, I suspect Canon had this idea long before ML...perhaps it was simply that ML got wind of this patent, and looked for a way to achieve the same thing with current Canon sensors...either way, interesting.

The more interesting thing to me than the dial gain, though, is the CP-ADC design. I've long said that Canon needs to modernize their sensor design, get rid of the noise generators (i.e. ADCs) in their DIGIC chips, and bring all that image processing onto the same die as the rest of the sensor. This is what Sony did (although they took it a step farther and converted to a digital readout/CDS approach, whereas as far as I can tell Canon's is still analog CDS and whatnot until it is actually converted to digital), and they achieved some significant DR benefits from the move.

Anyway, personally, I'm glad to hear Canon is investigating these options. CP-ADC is something I've wanted Canon to do for a long time, happy to see they might actually do it. God only knows if/when this technology may actually find it's way into their sensors...I only hope and pray it is soon. And dual-gain to boot...which has the potential to support FAR more than 14 stops of DR. With a 16-bit CP-ADC, we might even see a full 16 stops of DR (and who knows what might come after that...20-bit, 24-bit ADC? Can't imagine the file sizes though...46mp * 24bit...phew, 1.1Gb RAW (uncompressed) data size! Canon will need a DIGIC more than four times as fast as the current DIGIC chip...)

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