April 21, 2014, 01:57:32 AM

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Topics - jrista

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1
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: http://www.mreclipse.com/LEdata/TLE2014Apr15/TLE2014Apr15.html
For exposure tips, see here: http://www.mreclipse.com/LEphoto/LEphoto.html

2
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


Nebula
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

Galaxies
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:

3
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:

http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=6402677&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=#Post6402677

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.


4
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:

http://image-sensors-world.blogspot.com.es/2013/08/canon-files-for-dual-range-column.html

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...)

5
Software & Accessories / The Bane of Adobe Creative Cloud
« on: December 10, 2013, 05:17:49 AM »
I've been largely unhappy about Adobe Creative Cloud. Personally, I don't think it is fair to the huge numbers of freelance photographers, graphic designers, web designers, etc. who have effectively built their entire livelihoods on Adobe software. I think that Adobe, with a $50/mo fee for the full CC Master suite and $20/mo per-app fee, is greatly taking advantage of freelancers unmitigated and everlasting dependence.

That said, I decided to give the PS CC + LR5 $10/mo deal a try. It was the first deal that Adobe offered that seemed reasonable (we'll see if it stays that way in a year), and I wanted LR5. I still own PS CS6, and I prefer to use it as my primary editor...with SELECTIVE use of PS CC. Well, I've learned a few things, and I thought I'd warn people.

First off...Adobe CC is infectious. By that, I mean, once it is installed, the CC versions of it's products take over any automatic integrations and file associations. If you double-click a .psd, it opens in CC, rather than CS6. Worse, if you use LR, whenever you open images in Photoshop, it always opens in CC. The worst part is...there seems to be NO WAY to configure LR (either v4.x or v5.x) or other Adobe apps to use the Photoshop version of your choice...your STUCK with CC, unless you uninstall it...and then, you have the hassle of getting CS6 working again. Frustrating, and annoying...Adobe should allow their users to choose which version of Adobe products are used, rather than automatically forcing you to CC.

There is a deeper, more malicious demon lurking within Adobe Creative Cloud, however. I stopped using the .psd format a while ago. I never seemed to need the extra information that .psd stored over and above .tiff, so I switched to .tiff. As such, I NEVER expected that saving .tiff files created with Photoshop CC would not function properly in Photoshop CS6. I thought that since I was using a universal format, they would be compatible with anything that could load .tiff files.

Well, this plain and simply isn't true. An example is using smart objects. I use smart objects with stacked images, along with tweaking the stacking mode (usually mean & median), to do some pretty amazing noise reduction with still frames (macro, landscape) and astrophotography frames. Thanks to the issue described above, some of my recent astro stacks were done in PS CC, rather than PS CS6. I tried to open these .tiff files in PS CS6, and while they opened, they did not render 100% correctly. The issue? The "renderer" for the smart object stacks could not be found. PS CS6 supports exactly the same stacking modes, but Adobe cleverly changed how they store that information in .tiff files...so it is no longer backwards compatible.

So the warning here is, BEWARE! While Adobe says you can open files saved with Creative Cloud apps, they have apparently "tweaked" a few things here and there to make life difficult for those who try to get around their insane monthly fees and use their "bought and paid for" previous versions. Even if you save in universally supported file formats such as TIFF, your file compatibility is NOT guaranteed. You can work around some of these issues, but just beware...there may be some "tweaks" to how CC apps save data that might permanently bind a perfectly normal TIFF file to that CC app, preventing its use in a prior version.

This is the kind of maliciousness that I was afraid Adobe would employ. To my great dismay, it seems my suspicions were correct. The truly frustrating thing is, I cannot afford the extremely hefty upgrade prices for some of the apps I need to upgrade, such as Illustrator and Premier. Even worse, in many cases, my versions for some apps like Premier are too old to upgrade (CS3 era), and I'm required to pay full price. So, my options are to either subscribe to CC, and get locked in forever...or shell out an unholy amount of cash for a product I already own, but for which I simply need an upgrade. Despicable. Adobe is rapidly becoming my most loathed company.

Anyway...BEWARE...

6
Lenses / New Samyang 10mm f/2.8 ultrawide! Looks impressive...
« on: December 05, 2013, 10:13:04 PM »
Samyang 10mm f/2.8 Manual Focus Wide Angle Prime

This looks pretty impressive. Samyang has made excellent wide angle primes for a while, but this is the first time I've seen one with a nano crystaline coating on an internal lens element. Canon and Nikon have been using nanocrystal coatings on internal elements for a while, and it has a truly amazing impact on reducing flare (total transmission loss is in the range of 0.1%, vs. often more than 1% for basic multicoating.

For rectilinear wide field astrophotography, this lens could be a true dream come true...not to mention the applications for high quality ultrawide landscape photography (especially on full frame!)

Curious to see how corner performance is. If it is anything like the 14mm and 24mm Samyang lenses, it should be phenomenal...but 10mm is pretty darn wide...

7
Landscape / Deep Sky Astrophotography (Gear Discussion)
« on: December 04, 2013, 11:45:08 PM »
There is already a stars above thread, but that one seems to be about wide field astrophotography. I've been taking a bunch of photos of the comets flying through the sky lately. Only ones I was able to get a decent shot of was Lovejoy R1 (see the Comets thread).

I discovered an intriguing new technique for stacking very short deep sky frames in photoshop, one which nearly eliminates noise without affecting detail. I've been trying to stack short (i.e. 1-2 second) frames of the Orion nebula for a while, never with satisfactory results...always still too much noise. This new technique resulted in my first fairly decent photo:



  • Body: Canon EOS 7D
  • Lens: Canon EF 100mm f/2.8
  • Exposure: 1s f/2.8 ISO 1600
  • Frames: 30

I stacked the frames in the following way:

  • Import as Layers to Photoshop fron LR
  • Align all layers (did it manually, auto-align freaked out for some reason)
  • Select first 5 layers, Layers->Smart Objects->Create
  • Set stacking mode to mean, Layers->Smart Objects->Stack Mode->Mean
  • Repeat 3-4 for each group of 5
  • Rasterize each smart object
  • Set opacity mode to (from bottom most light frame): 100%, 83%, 66%, 50%, 33%, 16%
  • Set blending mode to Screen for all light frames
  • Add Levels adjustment layer and correct black point, white point, and gray point to bring out most detail
  • Tweak color, levels, curves, etc. to taste

8
Landscape / Comets
« on: November 27, 2013, 09:26:23 AM »
Well, this seems to be the month of comets. In addition to Encke, ISON, and the new Lovejoy, four other comets were discovered this month (C/2013 V1 (BOATTINI),  C/2013 V2 (BORISOV),  C/2013 V3 (NEVSKI), C/2013 V5 (OUKAIMEDEN)). Nevski and Oukaimenden are moving right along. Nevski is passing by the constellation Leo, and Oukaimeden is approaching Jupiter in the sky. Not sure if/when they might put on a show, but currently, we have Encke (a main belt periodic), ISON and Lovejoy sharing the sky and putting on a show for at least binoculars and telescopes.

Given the plethora of cometary beauties moving through the skies right now, I thought it might be worth it to start a Comet thread. I had originally intended to have a Celestron EdgeHD 11" with their DX equatorial tracking mount...but circumstances have left me with only a 600mm f/4 lens. Not particularly ideal, but it allowed me to get a basic shot of Lovejoy:



If you've been photographing comets (especially if you have a tracking mount and a telescope), post em here! Would love to see them!

9
Well, I thought I'd start a thread for this. Not sure if anyone will get anything...the moon is full tonight, nice and bright...and it may ruin the show. The Orionids were mooned out this year as well, and here in Colorado we had cloudcover.

The Leonids peak in the early morning hours before sunrise, which means the moon will be lower towards the western horizon. Leo will be up high in the sky, but hopefully any meteors radiating towards the east will be visible and capable of being captured by a camera.

As an extra treat, Comet ISON reached naked-eye visibility today, so it should be visible, a little below Mars near the horizon, around the same time that the Leonids peak. ISON is a fairly fast moving comet, and it hasn't brightened all that much, so with the hunter's moon you might not see anything...but still, worth a try I guess. ;)

Anyway, if you get any pictures, post 'em here!

10
Landscape / Waterscapes
« on: September 04, 2013, 02:22:44 PM »
The title says it all!

Here is my first. Small creek cascading down a mountainside near Long Lake, in the Indian Peaks Wilderness area of the Colorado Rockies. The entire creek was shrouded in yellow and light purple flowers.

Gear: Canon 7D + EF 16-35mm f/2.8 L II
Exposure: 2s @ f/16 ISO 100


11
Macro / Denizens of the Forest Floor
« on: August 22, 2013, 10:36:23 AM »
If you live in a forest, or have any photos of the forest floor dwellers such as mushrooms, lichens, mosses, etc. this is the place to post them. Macro and close-up work only. Does not matter what lens you use, whether you use extension tubes or reversed lens, etc. so long as magnification is 1:2 or larger (1:1, 2:1, ... 5:1).

Name: Puffball Mushroom (Lycoperdon perlatum)
Edible: Yes (when white inside)
Location: Long Lake, Brainard Lake Recreation Area, Indian Peaks Wilderness, Colorado
Equipment: Canon 7D + EF 100mm f/2.8 Macro



12
Landscape / Perseid Meteor Shower Aug. 11-12 2013
« on: August 10, 2013, 07:32:46 PM »
Just in case anyone likes photographing meteor showers, the Perseids peak on August 11th and 12th. I am not sure I'll be able to get any shots...Colorado has been experiencing pretty powerful thunderstorms every evening and through most of the night for about a week now. *sob!*  :'(

Anyway, if anyone manages to capture any night sky photos of the shower, I'd love to see some posted here! :)

http://www.space.com/22133-summer-meteor-showers-2013.html

13
I just read some of the reviews on the Lumia 1020. I have to say, from a photography standpoint, I am REALLY impressed. It finally brings the true PureView 808's 41mp sensor, the 6-element Zeiss lens from the 925, and full Xenon flash to a phone pretty much built for photography. Their pro photo software looks rather nice, giving you complete control over all the standard aspects of exposure (i.e. want to do a long exposure and blur people walking by...you can). I love the fact that it has the extended battery "grip" accessory, too.

http://www.nokia.com/global/products/phone/lumia1020


So, does this mark the true end of the point and shoot, and the beginning of full blown photography phones with all the features we *photographers* have come to expect from an actual camera? To date, phone cameras have been geared more towards the instagrammer crowd...the Lumia 1020 seems to be positioned more for pro photographers who want something simpler, but still just as capable, for a handy every-moment alternative to a DSLR.

Is it only me who thinks this?

14
I seem to have an issue with my EF 100-400mm lens. I just took it out to shoot Double-Crested Cormorants and some other birds the other day, first time since early February. The last time I used the lens, it was for pretty close up shots of smaller birds, such as Juncos and Chickadees, in my yard. When it came to the Chickadees, I did not see anything wrong at first with the shots. Yesterday, while photographing the Cormorants, it seemed the 7D AF locked on pretty well, even though the subjects were only filling 1/4 to 1/3 of the frame most of the time. I spent a few hours photographing, and went home with a couple CF cards full of photos. When I got home, it seemed as though 100% of the shots were soft and/or slightly out of focus. I've been using this lens with it's current AFMA setting for months, and it seemed to work at that setting before. To my knowledge, the lens has been sitting on a tripod, attached to my camera, in the same place since the middle of February...it hasn't been dropped or anything like that.

So far, out of quite a number of photos, I have yet to see one that I would call sharp or properly focused. Most of the shots seem to have the focal plane a few inches behind the subject, even though the 7D in AI Servo appeared to have locked onto the subject and tracked it while I held the AF button down (I use rear-button AF as taught by Art Morris.) The Camera is a 7D, no teleconverters used, and it was mounted on a GT3532LS tripod with the Jobu Pro 2. IS was in Mode 2, and was always active and stabilized before any shots were taken (so I don't think the issue is blurring caused by mid-exposure actuation of the lens' stabilization element group.) In addition to the softness and OOF issue, ALL of the highlights, even in the center of the frame, seem to have a coma-like shape. All of them are "stretched" towards the upper right corner of the frame.


(Not the best photo of the bunch...it just has a lot of spot highlights that demonstrate the problem well. Small highlight on the end of the bill, another in its eye, several on its wing feathers. The whole image overall appears soft. Focal plane looks to be slightly behind the bird, despite the fact that I was using center-point only AF in with rear-button AF, and it was right on the bird (LR doesn't show AF points, sadly, and I a

Since getting home, I've run the lens through FoCal, as well as a manual AFMA procedure, and I keep ending up at the same setting: -5. I've tested a bunch of shots indoors on well-lit objects, including those with very fine details (I have a calendar with extremely fine lines). Things look pretty sharp, however a numeral six right at the center of the frame also appears to have a slight lower left to upper right "blur":

NOTE: Click images to view them full size, to actually see the 100% pixel peeping view.

(I used AF with -5 AFMA. The diagonal blur appears when using live view contrast-detect AF as well...pretty much identical.)


I am beginning to wonder if the Junco and Chickadee photos from a couple months ago might even have some problems. Based on this 100% crop of an unprocessed Chickadee photo, I now see that the same lower left to upper right blur and coma-like highlight shape. There also appears to be some soft fringing around the beak and the top of it's head. The feather detail does not look as sharp as I thought it was...certainly not as sharp as I would have expected for how close the subject was, and the fact that AI Servo AF seemed to instantly nail it right on the birds eye. I rarely look at my photos at 100% like this...I usually process and sharpen at the "Fit" setting in Lightroom. At 100%, it definitely appears as though shots from over a month ago have the same problem as the shots today. I am guessing the issue is just more pronounced with more distant subjects like the cormorants (which had to be at least 8-10 times farther away).


(Shot from a few feet away, almost at the MFD of the lens. IS was off in most of these shots, with the camera mounted on a tripod with a gymbal head.)

It is also possible that I've just become spoiled. I have rented several of Canon's new Mark II telephoto and supertelephoto lenses. The sharpness on those is quite stunning, and certainly puts the piddly little old 100-400mm lens to shame in every way. However, that said, I do believe the funky coma-like highlight halos and stretching seem to just be wrong to me, and I do not remember seeing them in my photos from a number of months ago. Do I need to send in my lens for repair? If I do need to send it in, is it best to send the camera body with it for proper alignment, or will AFMA cover that? Thanks for any insight!

15
I just came across some articles written by ctein at The Online Photographer. He brought to light a term that I think would be very useful when it comes to discussing dynamic range of modern cameras. Frequently, the debate arises about what DXOMark's Print DR statistic means, usually in conjunction with the D800's whopping and hard-to-swallow rating of 14.4 stops. Some people have come up with the term "Photographic Dynamic Range" to refer to the thing most photographers think of when they hear "dynamic range", but the meaning of PDR is not super clear all the time. I think ctein's explanation in the two articles below is an excellent one, and I like the differentiation the term "Exposure Range" allows relative to "Dynamic Range". I think Exposure Range (apparently an existing term used in the film days) appropriately and accurately describes what most photographers think of when they hear "dynamic range". Dynamic Range, the way DXO describes it, is quite appropriately called Dynamic Range as it has to do with the "signal", not necessarily the usable range of tones in an "image", nor the characteristics or quality of the noise that may affect the exposure range of the image.

http://theonlinephotographer.typepad.com/the_online_photographer/2012/09/dynamic-range-is-not-exposure-range-part-i.html
http://theonlinephotographer.typepad.com/the_online_photographer/2012/09/dynamic-range-is-not-exposure-range-part-ii.html

Ctein also puts forward the notion that as many pixels comprise an image, it is theoretically possible for the exposure range to be higher than the dynamic range. He explains it in the second article. Interesting concepts. I am not sure how well it applies with RAW and raw editors these days...the expandibility of exposure range via dithering (which is effectively what Part II covers) is theoretically possible, but in my experience noise in the lower tonal range of a RAW image tends to have too high of a standard deviation to be effective as a medium for dithering. I've never used a top-end camera like the 1D X, however...perhaps its superior noise characteristics would.

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