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Messages - East Wind Photography

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31
EOS Bodies - For Stills / Re: The Canon EOS-7D Mark II AF Grid Void
« on: January 28, 2015, 12:11:49 PM »
East Wind & takesome1, thank you for your perspective as 1D X owners.  I had a feeling it wasn't quite as great as hyped (compared to the 1D X), but it still sounds like a huge leap over the 7D.  I think I'll keep an eye out for a refurb down the road, but the 1D X and 5DIII serve my needs just fine.

Also, keep in mind that Art Morris has pretty specific needs when it comes to AF, so I'm not surprised that he's more annoyed by this than most people.

Personally I think the 7d2 format offers. A Few advantages over the 1dx.  However if it can't produce an In focus image even 50 percent of the time, it's not really worth it.  A t2i produces more keepers. Just to put it Into perspective.

32
EOS Bodies - For Stills / Re: The Canon EOS-7D Mark II AF Grid Void
« on: January 28, 2015, 10:06:20 AM »
I am not annoyed by it, but honestly on still and slow moving subjects  I keep thinking 65 points on a crop sensor is a bit of overkill.

I find other things to complain about with the AF system though. Precision being the most prevalent and the ability to pick up a small point the next.

The comparison was made that it is the 1 D x's little brother. I hate car comparisons but the 7D II to the 1D X is more like a fully loaded Volt compared to a fully loaded Tahoe.  Both will get you where you are going, with AC and XM radio, but if you have driven both you definitely notice the difference.

Yes and I've even heard some of the reviews state the AF system may even be a touch better than the 1dx.  That is clearly not the case.  A lot of hype at the outset.  The AF system is great for larger subjects such as soccer players and motocross.

I am well experienced in case usage and settings having used the 1dx and own the 5d3 since release.  I have tried various settings to maximize bird in flight success and so far most of the results are dismal.  For BIF coming toward you at any rates of speed the AF system loses lock or can't keep up and best case you get about 5 to 10 percent in focus.  With the 5d3 you get about 90 to 95 percent in focus.  With the 1dx it's even higher...closer to 100%.

Also in zone AF modes the system is supposed to lock on the closest object in the zone.  90 percent of the time zone AF will lock onto the background.

I'm hoping some of this is just a firmware tweak in the phase detect software.

Short of that the 7d2 is a great camera but with only about 10% success rate for what I shoot its probobly going to spend more time in the bag and used for still subjects.

33
EOS Bodies - For Stills / Re: The Canon EOS-7D Mark II AF Grid Void
« on: January 27, 2015, 07:55:19 PM »
So this has not annoyed me at all.  Has not presented itself as an issue that I cannot compensate for.   The spacing could likely be due to the arrangement of the phase detect sensor lines.

I have my speculation based on AF characteristics and other anomalies I noticed that the phase detect sensors may actually be the same size as the ones used in the 5d3 and perhaps 1dx.  They occupy more real estate due to the smaller sensor size.  That could mean that even though the subject is magnified by 1.6x, the AF works no better than that in an respectfully reduced subject size in a full frame counterpart.

Does not really answer the gap issue other than perhaps the AF sensor spacing issue is also magnified by a factor of 1.6.

Thoughts?


34
Landscape / Re: Deep Sky Astrophotography
« on: January 21, 2015, 10:09:05 PM »
I guess I need to look at one in person. I have an old meade lxd75 that I could not get good tracking out of that I had intended to be portable mount. But at time I was using an 8" Newtonian that acted like a sail in the lightest breeze. I may dig it out and see how it behaves with a lens. I would love to have something easier to haul on trips.

This is the reason I got the Astro-track astrophoto package. The unit is about the size of two Dslrs (excluding the tripod) and I can pack in my luggage with the tripod.  It has an st4 interface as well so you can add a scope and guider to the setup for longer exposures.  I've taken up to 60 seconds on it and it tracks well even along the ecliptic. Haven't had a need to go much more than that yet due to light pollution. However I am planning a 2 week trip to Yellowstone next year and I'm shaking out all of the new gear now so I Dont have issues once I get there.  It seems to be the most portable option yet can easily handle the gear I intend to take with me.  300 2.8L ii, 5d3 and 7d2 Both with grips.

I think it's design capacity is 11kg.


35
Landscape / Re: Deep Sky Astrophotography
« on: January 21, 2015, 03:51:58 PM »
Looks like it tracked pretty well. What tripod did you use it on?

It's an induro carbon fiber that use with a wimberly mount ... Seems fairly stable with my 300.  When I mount the 600 on the tracker its gets a bit wobbly but does ok as well as long as there is no wind.

36
Landscape / Re: Deep Sky Astrophotography
« on: January 21, 2015, 01:26:33 PM »
This was 12x50 sec at iso1600 with my 7d2 and 300mm f2.8 II lens at f4.  No calibration.  Stacked in DSS and then stretched with pixinsight.

 I like  how you have processed it. What settings did you stack with ? Median should get rid of those satellite tracks .
  Steve

There is also one sub that did not register properly.  The sequence was a test right after I got my star-watcher tracker.  Was mainly interested in seeing how well it would track.  The stacking was an afterthought after I discovered the images again.  Once the skies clear up again I'll give it another run with some calibration frames.

37
Landscape / Re: Deep Sky Astrophotography
« on: January 21, 2015, 12:10:54 PM »
This was 12x50 sec at iso1600 with my 7d2 and 300mm f2.8 II lens at f4.  No calibration.  Stacked in DSS and then stretched with pixinsight.

38
Landscape / Re: Deep Sky Astrophotography
« on: January 19, 2015, 10:17:10 PM »
Great images, guys! I'm glad to see some of you are getting into astrophotography. :) It's a great hobby, especially if your an insomniac like me. :P


nightclicks, excellent results with M42 there. You managed to pull out some of the faint outer dust, which is really quite a challenge. You must have some decently dark skies to do that.

I used to do it the hard way back in the day.  Started out with a cold camera.  Used dry ice to chill the film down  to about -20F then exposed for hours tracking manually with a joystick.  I then upgraded to using hypersensitized film...soaking the film under temperature and pressure in nitrogen and hydrogen gas.  Cost more but you could treat several rolls of film at a time.  Stacking was something we did in the dark room by stacking multiple negatives in the enlarger and manually registering the stars.  It was all painful and extremely time consuming. 

Digital has really improved things quite a bit for astrophotographers.  You can achieve better results in far less time and effort once you learn the software side....and the best part is that can be done in the warmth of your living room.



39
Landscape / Re: Deep Sky Astrophotography
« on: January 19, 2015, 08:50:36 PM »
I see that I posted my Comet Lovejoy pic in the wrong sub-forum. It is a single exposure shot on a fixed mount tripod, nothing fancy - no equatorial mount, no image stacking. Just an 85mm f/1.4 lens @ 1.4 and ISO 3200 for 10 secs (so some earth spin is evident). Camera = 7D2 (pic already in 7D2 sub-forum). I can just barely detect a comet tail.

Nice shot.  With this focal length and keeping the crop down you should be able to take it to 6400.


40
Landscape / Re: Deep Sky Astrophotography
« on: January 19, 2015, 01:21:06 PM »
Here is Lovejoy last night.  Clouds parted very late so no tracking.  Iso6400 20x5 seconds, 100mm at f4.  Light pollution was problematic.  I stacked these in DSS then edited on my iPad. Was surprised to catch the reflection nebula in the Pleiades.

41
Landscape / Re: Deep Sky Astrophotography
« on: January 17, 2015, 06:31:48 PM »
Here is comet Lovejoy from last weekend.  I'm still learning pixinsight and that is much more daunting than actually taking the subs.

Working on some new subs I took last night.  Good split in the tail.  My biggest issues are finding any clear instructions on the finer settings within the tool.  Experimentation seems to be the best way to learn.

42
Lenses / Re: Quick Comparison: Canon's new 400mm Options
« on: January 13, 2015, 12:11:54 AM »
Keeping in mind the whole premise of a zoom is flexibility over IQ (of which isn't really an issue anymore either) the difference in transmission I doubt will influence the majority of buyers.

It really depends on what you shoot...and how deep your pockets will let you go.  A zoom is ALL about flexibility and in very few instances do they equate to the same IQ as a prime of the same FL.  The only one that comes to mind is the 200-400.

I shoot wildlife with my primes.  Sold all of my zooms (except the 70-200 2.8L IS II) and would not buy any of the latest except the 200-400 but my pockets aren't big enough ..yet.

43
Lenses / Re: Quick Comparison: Canon's new 400mm Options
« on: January 13, 2015, 12:04:57 AM »
Primes will always beat zooms in light transmission due to fewer optics.  There is an advantage to primes that most people don't realize.

I find primes have about a 1/2 stop advantage over zooms of similar apertures.

Yep and for most who require big teles for wildlife also require better low light capability and 1/2 stop can make a difference in the morning or late evening or when adding an extender to the mix.

The actual difference is more like 1/6th of a stop.
Example:  70-200/2.8L IS II T-stop=3.6, 200/2.8L II T-stop=3.3.

depends on the number of optics.  For that lens 1/6 may be correct.

What other pairs can be checked?  As far as I can think of, the only other one is the 100-400L and 400/5.6L where the f-stops and focal lengths are the same between prime and zoom.  The 400/5.6L hasn't been tested.

You could also compare the 70-200 2.8L II to the 100 F2.8L Macro and a host of others.  Logically one would compare the lenses wide open when possible. You can compare other lenses if you stop down the prime.  For example compare a 70-300 to a 300 2.8 stopped down to F5.6.

The light transmission benefit also holds true at similar F-stop settings.

44
Landscape / Re: Deep Sky Astrophotography
« on: January 12, 2015, 11:46:42 PM »
Yeah, I've been having a lot of problems with DSS comet stacking as well. I found a PDF recently that explained a specific imaging procedure. The guy was imaging with a mono CCD with color filters, so his sequencing was complex. The trick was to use 20-second gaps between frames to ensure that stars were fully separated from each other. That is the only way that DSS will be able to properly apply kappa sigma clipping to reject stars when it registers on the comet. Anything else, and you'll have problems.


I've been integrating with PixInsight, and have had largely the same problem as with DSS. I think the star-gap technique is the right way to image a comet. If I get another change, I'll be employing it.

Ah interesting.  Since I took 130x20sec subs, I can use every other one that passes a decent score and see how that works.  That gives me a 21 second gap between subs.  Surely I can get at least 40 subs still.

So one of the issues I a see with pixinsight comet integration is that it assumes all subs are taken without moving the field of view.  That is you specify where the comet is on the first and last subs and it interpolates the position on every other sub.  I guess you have to do a star align on every sub first to normalize the fov then do comet integration.


Yes, generally that's how comet imaging works. Most things assume that (DSS does for it's default integration, where you only mark the comet in the first and last subs sorted by time index.) If you change the field between subs, then your on your own. :P

Wow.  PixInsight with 8 subs and no calibration already has done better than DSS and photoshop.  Need a few more days of learning before I have something to post.

45
Landscape / Re: Deep Sky Astrophotography
« on: January 12, 2015, 11:45:53 AM »
Yeah, I've been having a lot of problems with DSS comet stacking as well. I found a PDF recently that explained a specific imaging procedure. The guy was imaging with a mono CCD with color filters, so his sequencing was complex. The trick was to use 20-second gaps between frames to ensure that stars were fully separated from each other. That is the only way that DSS will be able to properly apply kappa sigma clipping to reject stars when it registers on the comet. Anything else, and you'll have problems.


I've been integrating with PixInsight, and have had largely the same problem as with DSS. I think the star-gap technique is the right way to image a comet. If I get another change, I'll be employing it.

Ah interesting.  Since I took 130x20sec subs, I can use every other one that passes a decent score and see how that works.  That gives me a 21 second gap between subs.  Surely I can get at least 40 subs still.

So one of the issues I a see with pixinsight comet integration is that it assumes all subs are taken without moving the field of view.  That is you specify where the comet is on the first and last subs and it interpolates the position on every other sub.  I guess you have to do a star align on every sub first to normalize the fov then do comet integration.

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