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Messages - jrista

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1306
Landscape / Re: Deep Sky Astrophotography
« on: January 04, 2014, 07:33:18 PM »
While out at my dark skies site the other day, I also managed to get some wider field milky way shots. I think you can even see some airglow in these photos (the green and red haze in the bottom half):






1307
Landscape / Re: Deep Sky Astrophotography
« on: January 04, 2014, 07:30:36 PM »
This is imho the most inspirational thread I have read in this forum for quite a while!

I have never tried astrophoto myself (except when I was lucky to borrow the 800/5.6 with a 2xIII TC to take picture of the moon, but that would hardly count as the moon is very bright so the exposure time is very short).

I have been reading this whole thread on my ipad retina, and it has quite good resolution. However, due to the restrictions on image size here in CR, I would have loved to see full resolution images of your beautiful pictures if you guys have posted them somewhere else? :)


Glad your finding it inspirational! :) I find the sky to be quite inspiring in and of itself. :D

Regarding larger resolution images, personally, I don't have anything really high resolution. You can find all my work at jonrista.com, and the images there will be a little higher resolution. I downsample them all right now to reduce noise (at full size, they really don't look all that good.) Once I am able to get a tracking mount, I hope to produce MUCH larger and more detailed images, and I'll happily share them. Not sure when that will be, though...few months away at least, if not the end of the year.

1308
Landscape / Re: Deep Sky Astrophotography
« on: January 04, 2014, 07:27:35 PM »
    Any problem when you use those fast lens with the Astronomik filters?? I thought they are design for f3.8 to f15...

    By the way, now they have clip on filters for Canon 5D and 6D full frame camera, but I think you had to lock the mirror in up position to install the filters, so might not be that useful if you need the viewfinder to aim.


Is that right? I'll have to see - using the 5DIII would improve things a lot. One thing that's relevant in any case is the Astronomik EOS clip filters (for 1.6 crop bodies) actually fit into the super telephoto lens rear filter holder (on my 500 II at least). Sadly my tracking mount can't handle the weight of that lens and body combination, so I've never made much use of it - but it's worth knowing.

As for aperture, I suspect it's the reason I get a lot of halos around stars. They are, as you say, rated for medium to narrow apertures (by lens standards). With the UHC filter, many stars get bright magenta halos, which can be a pain to remove if your main subject is a red/pink nebula. Nonetheless, other than that, I've found no problems, and a tradeoff worth making in my experience.


Hmm! I'll have to check out Astronomik's filters for the supertelephoto lenses. I have the 600/4 L II, which is basically like a good Apochromatic refractor. I have my eye on the Celestron CGEM DX mount, which is about $1200 alone, and it should be able to hold my lens and camera quite easily. Having a light pollution filter would make it a lot easier for me to do some deep sky astrophotography without having to find time to drive an hour or so out of town to find clean dark skies. Thanks for the tip!

Edit: here's one of my early attempts at Andromeda galaxy with the 135L at f/2, CLS filter on 600D (unmodified). 100% crop, processed. I have got a bit better since then... :)




I'd have been very happy with that! Andromeda is a target I've struggled with. Partly because it's hard to locate (no very bright nearby stars) and partly my filter seems to bring out hydrogen emission nebulae much better than galaxies or reflection nebulae (e.g. the Pleiades).

Incidentally, the 135L is a lens I've considered as my next step for this work. Would you recommend it? The 100L macro has done pretty good service so far, but I'd love more reach (and as I say, the 500L II is too heavy for my tracking mount).


Ditto! I'd have been happy with that, too! That is really quite good for just the 135L. I guess I would have gone with a different white balance, but that is a pretty darn nice photo! Out of curiosity...did you use a tracking mount? Signal strength looks pretty good in that shot...a hell of a lot better than I've ever been able to get with my 100mm f/2.8. Stars are nice and round, too...something I've never been able to get without tracking.

1309
Landscape / Re: Deep Sky Astrophotography
« on: January 03, 2014, 03:27:51 PM »
Reprocessed a few times with DeepSkyStacker. Tweaking the final result is a real PITA, but when you figure out how to do it right, the results are much better:



I dunno if my experience is relevant, but I held out for as long as I could before I got a tracking mount. You can do good stuff with short exposures if you go through the proper motions of dark and flat frames, and stacking a lot. Dark skies/astro filters probably make the most difference beyond that. I do all my aligning and stacking by hand in Gimp (I'm not sure any of the good free astro stack/align software is available for Macs, but anyhow that's what I'm used to now). Having said that, a tracking mount can push things further than anything.


You can extract a certain degree of quality from non-tracked stacking, but there is a limit. With short exposures, you have a very low signal strength. While you can improve SNR with stacking, you can't improve the actual image signal strength beyond a certain point, so you can never get the nice fine detail that a long exposure gets you. I've spent about two months now trying...and the shot above is about as good as I think I'll be able to do without tracking (or exceptionally dark skies, which are really rare and hard to find.)

I have done a fair amount of manual stacking in Photoshop, and the results can be quite good. Stacking software, especially the more complicated versions like DSS, Nebulosity, etc. are much more capable, but they have a high learning curve, and often their toolsets are difficult to use. I have avoided DSS up till now, but I just spent the bulk of the day working on the shot above, and I think I finally have it figured out. It's a bit noisy (it got much too cold last night, and I packed it in before I took dark frames and bias frames), but that can easily be delt with.

Exposure times of tens of seconds up to minutes can be transformative.


Indeed! I can't wait to get my hands on the Celestron EdgeHD 11" CGEM DX. I had my eyes on a 5D III for my next photography, but I think I'm going to move the telescope to the top of my list. I am curious to see how the 7D II turns out, and for astrophotography, no DSLR will really do what I want, so I'm planning on getting a monochrome CCD with the biggest pixels I can find (probably around 9µm to 9.5µm, or perhaps 5µm with the option to 2x2 bin) an dual-stage peltier cooling (which gets you up to around 77% Q.E.) I'll then be able to filter Ha, Hb, Luma, R, G, B, and any other bands independently, and blend them in post for very high detailed, full-color wide band images.

It's -33C here tonight.... I'm not terribly worried about peltier cooling :)

I have an 8" Celestron with a tracking mount.... I have tried the 60D on it, but there is WAY to much noise... My friend's 5D2 work's much better, but it is an hour's drive away and that rules it out most of the time...


If you have a tracking mount, you should be able to do worlds better than I can with the 60D. You could expose for minutes, which would create a very strong signal. You could then stack, and median averaging or something like Kappa-Sigma clipping in DSS would clean up the noise right away. I think your selling your 60D a bit short. My shots are about as good as I can do with a 7D right now because I lack a tracking mount...if I had one, I guarantee you I'd be making MUCH better shots.

There is no question that a FF sensor would do better, but the problem with the 7D (or any Canon 18mp APS-C body) with non-tracked shots is the fact that they have pitifully low signal and crappy read noise. If you can make the signal strength 100 - 1000 times more powerful, then even Canon's 18mp APS-C bodies will do very well (I've seen a lot of exceptional astrophotography from the lowly rebel series when they are used on tracking mounts.) You should give your 60D another try, and do something like 30x10 minute exposures (five full hours of tracked exposure)...I would bet the results would blow anything I've posted here WAY out of the water.


I have been thinking of getting one of these.... http://focusscientific.com/osCommerce/catalog/product_info.php/cPath/94_47/products_id/649
or
http://focusscientific.com/osCommerce/catalog/product_info.php/cPath/94_47/products_id/650


For a first astrophotography camera, I suspect I'll get the Celestron Nightscape CCD. I've seen some truly amazing images made from it, and it isn't too terribly pricey (around $1500 most of the time.)

The cameras I really want in the long run, though, are these beauties:

QHY11 FF Monochrome

Full frame, 11mp, huge 9µm pixels, monochrome, FWC ~= 6D or 5D III (around 60ke-) with Kodak CCD, read noise ~13e-.

QHY23 Monochrome

APS-C, 9mp, small 3.69µm pixels, supports 2x2 and 4x4 binning (7.38µm and 14.76µm effective pixel sizes), highest Q.E. on the market for an astro CCD @ 77% (visible green, 60% Ha & 70% Violet/Ultraviolet), FWC ~= 7D/60D/Canon 18mp APS-C (around 20ke-) with Sony CCD, read noise ~5e-.

I figure I would want both, depending on the thing I am imaging and how finely I want to delineate detail. Probably years away from getting either...the FF one is $4000, and the cropped one is $3000. :P I am sure the Celestron Nightscape will do in the interim. The one thing that seems strange to me is the readout rate of most CCD astro cameras. The often list the readout rate at Xmegapixels per second, and usually that X is significantly lower than the total megapixels on the sensor. So, for an 11mp sensor with a 1mp/s readout rate, it would take a full 11 seconds to read out the whole sensor. For the 9mp sensor, it would take over 7 seconds to read out the whole sensor. I suspect that has to do with maintaining low read noise...but it was still surprising.

1310
Landscape / Re: Deep Sky Astrophotography
« on: January 02, 2014, 11:12:50 PM »
Reprocessed a few times with DeepSkyStacker. Tweaking the final result is a real PITA, but when you figure out how to do it right, the results are much better:



I dunno if my experience is relevant, but I held out for as long as I could before I got a tracking mount. You can do good stuff with short exposures if you go through the proper motions of dark and flat frames, and stacking a lot. Dark skies/astro filters probably make the most difference beyond that. I do all my aligning and stacking by hand in Gimp (I'm not sure any of the good free astro stack/align software is available for Macs, but anyhow that's what I'm used to now). Having said that, a tracking mount can push things further than anything.


You can extract a certain degree of quality from non-tracked stacking, but there is a limit. With short exposures, you have a very low signal strength. While you can improve SNR with stacking, you can't improve the actual image signal strength beyond a certain point, so you can never get the nice fine detail that a long exposure gets you. I've spent about two months now trying...and the shot above is about as good as I think I'll be able to do without tracking (or exceptionally dark skies, which are really rare and hard to find.)

I have done a fair amount of manual stacking in Photoshop, and the results can be quite good. Stacking software, especially the more complicated versions like DSS, Nebulosity, etc. are much more capable, but they have a high learning curve, and often their toolsets are difficult to use. I have avoided DSS up till now, but I just spent the bulk of the day working on the shot above, and I think I finally have it figured out. It's a bit noisy (it got much too cold last night, and I packed it in before I took dark frames and bias frames), but that can easily be delt with.

Exposure times of tens of seconds up to minutes can be transformative.


Indeed! I can't wait to get my hands on the Celestron EdgeHD 11" CGEM DX. I had my eyes on a 5D III for my next photography, but I think I'm going to move the telescope to the top of my list. I am curious to see how the 7D II turns out, and for astrophotography, no DSLR will really do what I want, so I'm planning on getting a monochrome CCD with the biggest pixels I can find (probably around 9µm to 9.5µm, or perhaps 5µm with the option to 2x2 bin) an dual-stage peltier cooling (which gets you up to around 77% Q.E.) I'll then be able to filter Ha, Hb, Luma, R, G, B, and any other bands independently, and blend them in post for very high detailed, full-color wide band images.

1311
Landscape / Re: Deep Sky Astrophotography
« on: January 02, 2014, 04:54:24 PM »
Did some more astrophotography last night. Worked on some wide field stuff, using my 100mm f/2.8 macro lens. Managed to get some decent results with stacking, but the 7D's low SNR is really killing me. Here is the axis of nebula in Orion:



From the bottom, you have M42 (Orion Nebula), M43 (De Mairan's Nebula), IC434 (Emission Nebula behind Horse Head), NGC 2024 (Flame Nebula) and M78 (follow the axis of orion, horse head, and flame nebulas up near the top edge, small smudge is a reflection nebula.) This is a stack of 30 frames, each 8 seconds long, ISO 3200.

(NOTE: The noise of the 7D, even after median stacking, is simply too great to eliminate with such short exposures and low signal. I pushed the exposure around as much as I could without making the noise overly apparent, but blah...if you see a lot of it, your screen is to bright!! :P Hope a 5D III (or better, a decent telescope and a peltier-cooled CCD astro camera) finds it's way into my hands sometime in the near future. ;))

1312
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: January 02, 2014, 12:47:21 PM »
what about following (naive fallacy):

EOS 5D Mark II
Introduced November 2008

...41 months...

EOS 5D Mark III
Introduced March 2012

...41 months would be...

EOS 5D Mark IV
around August 2014

???

You are a year early...August 2015. And I think that is a MAYBE. The 5D III is already extremely good. I think Aug. 2015 would be the earliest we might see an announcement for a 5D IV, but I really don't suspect one will actually hit the shelves until sometime 2016.

1313
Animal Kingdom / Re: Show your Bird Portraits
« on: December 30, 2013, 02:09:23 AM »
Mooned by a snowy owl......

Hey man, at least you WERE mooned by a snow owl...they stay completely out of human sight and only moon each other around here... ;P

1314
Third Party Manufacturers / Re: Sony A7R shutter vibration problem?
« on: December 29, 2013, 01:13:56 AM »
Just when many of us were celebrating the end of the mirror slap. :( Moving parts shutter weigh far less than the mirror, and shake is more noticeable?. :-\

No just as CR guy says - because the camera is much lighter than your typical FF DSLR and with a longer lens attached via lens collar and foot, the camera is just hanging in mid air. Normally thats cool on a rock solid 1DX or whatever but somehow on the A7R it's floppin about when the shutter moves. Even the tiniest vibration can muck up a shot with a tele lens.

Mirror slap is not an issue with DSLRs on a tripod due to mirror lock option.

Another reason why the "big and bulky" mirror slapping DSLRs still have plenty of life left in them. There will always be something to be said about ergonomics and solidity.

1315
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 28, 2013, 07:11:59 PM »
For instance, I highly doubt this new sensor will exceed (or even equal) the dynamic range of the existing 24 MP 1.5x sensor being used across the way.  How could it?  It's going to have smaller photosites, by definition, so each will get less photons.  Do any of you really see a quantum leap in crop sensor performance coming soon from Canon?  I don't.

I'd be surprised if Canon's sensors don't move to back-side illumination pretty soon.  It's a quantum leap for high-density sensors like the ones used in cell phones, but the benefit would be smaller in a sensor as big as APS-C unless the sensor's resolution were utterly insane.  Either way, though, it should improve the SNR, and should compensate somewhat for the shrink in pixel size caused by a resolution increase, though I'm not sure exactly how much.

If Canon doesn't move to a 180nm process, moving to BSI on a 500nm process could actually result in fairly significant gains for an APS-C sized sensor. It is absolutely necessary for the tiny form factor sensors in phones and the like these days...hell, some of those sensors might almost be single PIXELs in a larger format sensor given how small they are. :P BSI wouldn't be absolutely necessary for Canon's APS-C, but it would probably offer a greater benefit than for any manufacturers already using 180nm or 90nm processes.

That said...moving to BSI requires a fairly hefty investment in fabs anyway...Canon might as well move to 180nm or a smaller process AND do BSI given the cost necessary to do either one.

1316
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 28, 2013, 07:08:41 PM »
well, for a 2014 announcement, the bare minimum in sensor performance Canon needs to deliver in a 7D successor is the Nikon D7100 ... 24 MP, no DPLF (AA-Filter), excellent IQ and very good DR - more than 1 step up from Canon's pre-historic 18 MP APS-C sensor!

If Sony/Nikon can "cram that many pixels" onto a APS-C sensor and get excellent IQ from it, so should Canon. Crop 1.6x vs. 1.5x makes hardly a difference in real life. If Canon can't even achieve that much, they might as well pack up their entire APS-C business and call it quits.

That's why I absolutely expect a 24MP (or maybe 26MP) sensor in the 7D II. Of course with dual pixel-AF, plus an (even) better phase-AF module. Slightly faster too ... 9 or 10 fps. WiFi, GPS built-in and also [finally!] a RT radio wireless flash controller. After all, the 7D was the first ever Canon EOS camera to include an [optical] wireless speedlite master controller. Plus a fully articulated, touchscreen LCD - which Canon has learned to make some time ago already (EOS 650D). Plus some video-optimized stuff, bingo! No really innovation needed. 

Price tag? USD/€ 2199,- ... in line with Canon's pricing decisions in its more recent history. ;-)

Two things in all that I most certainly hope they do NOT do. First is the articulated screen. HELL NO. For one, the articulated screen makes it much harder to weather seal the body, and weather sealing is VASTLY more important for the 7D line. Additionally, it is just another part to break. Either whatever sealing Canon manages to stuff into the joint will eventually wear out, nullifying any other weather sealing...or the whole damn screen could break off. Articulated screen + professional model? Nah, I don't see it happening, and if it did, that would forever end my use of the 7D line.

As for the AA filter, at best, Canon should offer the option if there are really that many people who want it. I personally don't understand the trend towards more moire and worse aliasing...it's an odd trend. It is also largely a gimmick. An AA filter restores proper resolving power, eliminating nonsense data and massaging it into useful data. I don't really believe there are enough people who want AA-filter-less cameras that Canon would do this. Again, though, if they only offered a version without an AA filter, and none with, that too would probably end my use of the 7D line. I photograph birds...lack of an AA filter would decimate fine feather detail and leave it riddled with color moire, and there is no way to clean that up in post.
I agree 100 percent on the AA filter.

The articulated screen is slightly different logic, but I end up in the same place. I find the articulated screen to be a very useful feature and would not want to have a camera without one.... But the addition of WiFi and touchscreen interfaces takes things to the next level.... If you can have a phone or iPad that does the same things as the articulated screen, you end up with the possibility of a detached screen that is WAY more versatile than any articulated screen could be. For that reason, I think that the convenience of an articulated screen is less important on newer cameras than it was on previous models, and at least for me, having an articulated screen on a WiFi enabled camera is a non-issue.

We should be seeing more convergence between tablets/phones and DSLRs.

Don't get me wrong, I totally understand the value of an articulating screen, and would love one. But, not at the sacrifice of device durability and weather sealing. Not for the price rance the 7D line generally lives in, anyway (a $800 or cheaper camera is a bit of a different deal...you break the screen, it isn't such a huge deal, nor as costly to fix.)

As you say, though, WiFi changes the game, and makes the whole articulated screen pointless and less capable than the potential alternatives.

1317
EOS Bodies - For Stills / Re: The Unthinkable: Swapped out 5D3 for 6D
« on: December 28, 2013, 12:59:50 PM »

The increase in subject size in the frame is often offset by increased detail, which provides a greater potential that the AF unit will find the necessary contrast to operate well. The bigger issue with wide swings in subject distance is AFMA...bummer of it is, AFMA really works for the focal length you tune it at. Much closer or much farther, and the AFMA setting is not going to be ideal. Puts a lot of pressure to make sure you AFMA at the most ideal "happy medium" point somewhere between your average far distance and average near distance...but it will never be perfect for all photos. So, even if you do manage to maintain good focus with a nice contrasty area of the bird, doesn't necessarily mean it will be sharp as a brand new razor.

I agree, and have found the same, and I didn't need to buy a shiny new 600mm ii like you did, to discover it.  Obviously your new lens is so sharp that it simply helps highlight such problems.

Regarding what I highlighted in red, I assume you meant "fine tune AFMA to subject distance", or "focus distance", rather than "focal length".  Obviously changing focal length is a whole other issue, such as with a zoom.  Which is why cameras like the 6D and others, allow you to at least set AFMA at the long end and wide end independently.  It's a shame they don't also just allow you to also set it relative to the focus (or subject) distance...besides letting you just vary the AFMA all over the place with a zoom, at perhaps 10 or more different focal lengths, at randomly customizable focal lengths for example. 

When lenses get as sharp as yours, or perhaps moreso one like the 300 f/2.8 ii, then such things become more noticeable. 

At some point though, you have to decide if you are more gearhead, or more photographer.

Yes, I mean focus distance...sorry. :P

1318
Lenses / Re: Patent: Canon EF 300-600 f/5.6 w/1.4x TC
« on: December 28, 2013, 12:57:58 PM »
That's right. If the 300f2.8ISII with its AF speed cut in half is still as fast as other prime lenses already known for being blazing fast, the bare lens has got to be something incredible.

It is indeed something incredible. :D It was the first great white lens I rented...which is what got me hooked on 'em. Because of the incalculable performance of the 300/2.8 II, I am now forever slaved to buying the EF Mark II supertelephoto primes...nothing else will ever do. :\

1319
EOS Bodies / Re: A 2014 Roadmap Part 1: The 7D Mark II is Coming [CR2]
« on: December 28, 2013, 12:56:09 PM »
well, for a 2014 announcement, the bare minimum in sensor performance Canon needs to deliver in a 7D successor is the Nikon D7100 ... 24 MP, no DPLF (AA-Filter), excellent IQ and very good DR - more than 1 step up from Canon's pre-historic 18 MP APS-C sensor!

If Sony/Nikon can "cram that many pixels" onto a APS-C sensor and get excellent IQ from it, so should Canon. Crop 1.6x vs. 1.5x makes hardly a difference in real life. If Canon can't even achieve that much, they might as well pack up their entire APS-C business and call it quits.

That's why I absolutely expect a 24MP (or maybe 26MP) sensor in the 7D II. Of course with dual pixel-AF, plus an (even) better phase-AF module. Slightly faster too ... 9 or 10 fps. WiFi, GPS built-in and also [finally!] a RT radio wireless flash controller. After all, the 7D was the first ever Canon EOS camera to include an [optical] wireless speedlite master controller. Plus a fully articulated, touchscreen LCD - which Canon has learned to make some time ago already (EOS 650D). Plus some video-optimized stuff, bingo! No really innovation needed. 

Price tag? USD/€ 2199,- ... in line with Canon's pricing decisions in its more recent history. ;-)

Two things in all that I most certainly hope they do NOT do. First is the articulated screen. HELL NO. For one, the articulated screen makes it much harder to weather seal the body, and weather sealing is VASTLY more important for the 7D line. Additionally, it is just another part to break. Either whatever sealing Canon manages to stuff into the joint will eventually wear out, nullifying any other weather sealing...or the whole damn screen could break off. Articulated screen + professional model? Nah, I don't see it happening, and if it did, that would forever end my use of the 7D line.

As for the AA filter, at best, Canon should offer the option if there are really that many people who want it. I personally don't understand the trend towards more moire and worse aliasing...it's an odd trend. It is also largely a gimmick. An AA filter restores proper resolving power, eliminating nonsense data and massaging it into useful data. I don't really believe there are enough people who want AA-filter-less cameras that Canon would do this. Again, though, if they only offered a version without an AA filter, and none with, that too would probably end my use of the 7D line. I photograph birds...lack of an AA filter would decimate fine feather detail and leave it riddled with color moire, and there is no way to clean that up in post.

1320
Animal Kingdom / Re: Show your Bird Portraits
« on: December 27, 2013, 10:03:50 PM »
Scarlet Macaw, Disney's Animal Kingdom
(6D, 24-105 @ 1/125, f8, ISO800,105,  about 1:1 crop)

Beautiful. Love that detail! Reds are a bit bright...might try using some selective color editing to pull them down a bit, without otherwise adversely affecting the rest of the image.

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