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Messages - weixing

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Software & Accessories / Re: Gimbal Head: Wimberley Vs Jobu
« on: May 07, 2014, 02:40:02 PM »
    I have the BWG-Pro Gimbal and it's can convert to both side mount or full gimbal mount. But I prefer the full gimbal over the side mount because you can adjust the center of gravity with a full gimbal... useful when you mount a flash or a mic on your camera which change the center of gravity.

    Anyway, I prefer when I point my lens at any angle, the lens stay there when I release my hand without the need to tighten the tension knob or lock it down.

   Have a nice day.

Lenses / Re: EF 400L f/5.6 vs. Tamron 150-600
« on: April 28, 2014, 09:32:46 PM »
if the key is to get the shot, only one of the choices goes to 600mm w/o a teleconverter.  I have more "winners" by far with my Tamron 150-600 than I ever had with my 100-400L, 300 f4 L + TC, etc etc

My experience as many tests have shown is that at 500mm the Tammy outperforms the 100-400 at 400. At 600mm  I never shoot under F8 and am happy with it.  The 400 5.6 L is great too, but again, it's only 400, no IS/VC, etc

My only dislike of the Tammy is the weight, I personally must use a monopod or tripod to keep it steady. But I couldnt even get a 600mm F4 out of the case if that was my other choice.
   For a 600mm lens, the Tamron 150-600 is light and the IS work very well. I'm not a strong guy, but I can handheld the Tamron 150-600 at 600mm steady for just long enough for me to frame and take a decent shot... I was unable to do that with my EF400mm F5.6L.

  Attached is a 100% crop of a shot I recently took at 600mm F6.3 handheld. Just crop and export using lightroom default setting with no other processing done. I think the lens sharpness is not bad at F6.3 if you get the focus right... the only problem is that the DoF is very thin at 600mm F6.3... when the eye area is in focus, the back of the bird is out of focus... ???

  Have a nice day.

Lenses / Re: EF 400L f/5.6 vs. Tamron 150-600
« on: April 27, 2014, 09:56:46 AM »
    I had both the EF400mm F5.6L and Tamron 150-600mm. Here is my experience on my copy of EF400mm F5.6L and Tamron 150-600mm on Canon 6D.
On sharpness at 400mm, basically my Tamron 150-600mm is as sharp as my EF400mm F5.6L... ok, at F5.6, my EF400mm F5.6L is slightly sharper, but only visible at 100% crop. But when compare with EF400mm F5.6L + Kenko 1.4x Teleplus Pro, my Tarmron 150-600mm (500mm to 600mm) is sharper even at wide open.

On AF speed, the Canon EF400mm F5.6L is faster and more consistence than the Tamron 150-600mm on my 6D as expected. Also, my Tamron 150-600mm had one issue when using AI servo AF... when continuously AF on an object, sometime it'll "jump" out of focus a bit and then re-focus back... I don't remember this happened before on my EF400mm F5.6L even with the kenko 1.4x TC on, but not sure whether is this a common issue, so if you mainly shooting action shots, you might want to consider again.

Anyway, for me, I now mainly use the Tamron 150-600mm for my birding as I seldom shoot action shots and the Tamron IS is quite good, so I don't need to bring my tripod and gimbal head all the time when out for birding, but I think I'll still keep the EF400mm F5.6L as a backup... frankly, I'm not sure how reliable the Tamron 150-600mm is in the long run.

   Have a nice day.

EOS-M / Re: Canon EOS M3 in Q3 of 2014?
« on: April 15, 2014, 08:54:43 PM »
Looks like Canon is pasting feathers on a turkey hoping it will fly.  They ought to lay off the whole group that
worked on this - and then fire the management team that approved it.
    For your info, wild turkey can fly... :P

    Have a nice day.

EOS-M / Re: Canon EOS M3 in Q3 of 2014?
« on: April 15, 2014, 09:12:28 AM »
    IMHO, may be a hybrid DSLR will be the answer… just installed an EVF on the prism, so when the mirror went up, the EVF will turn on. There will be a physical switch that will lock the mirror in place when in mirrorless mode.

     So, those who want a small body, go for the M and those who want a bigger form factor or OVF, go for the hybrid DSLR.

     Have a nice day.

Landscape / Re: Astrophotography - which camera?
« on: April 11, 2014, 01:00:20 PM »
    I photograph it 2 years ago using my Canon 60D and Canon EF400mm F5.6L + Kenko 1.4x (560mm @ F/8). Pre-focus and meter using Jupiter. The ISS is very small in the image... I think SCT/MCT telescope are more suitable.

    Anyway, the attach image are from the best shots I got... all enlarge 2x... that's how small ISS is using 560mm lens. For those who interested to try, I use manual mode, shutter speed of 1/1000s and ISO 1000. The above settings is only for your reference as ISS brightness vary a lot.

    Good luck and have a nice weekend ahead.

Landscape / Re: Astrophotography - which camera?
« on: April 11, 2014, 07:52:17 AM »
Hi Don,

thanks - 7D it is then, and thank you for the additional advice - wouldn't have thought about using the moon for exposure.


Grant  :)
   I think Moon is still too bright... Last time I use Jupiter for pre-focus and exposure.

   Good luck and have a nice day.

The irony of it is that these DSLR bodies are highly resilient to physical abuse, but an impact can shift the position of the AF module enough to cause problems.


I once dropped my 5DII from waist level to the pavement.  Not even a cosmetic scuff on the camera, and it functioned fine afterwords except that all of my AFMA values shifted by ~10 units.

HI Neuro

Any idea of the physical dimension of the shift?

It doesn't take much.  The shift was a bit more that one full depth of focus *the sensor-side equivalent to depth of field); one AFMA unit is 1/8 the depth of focus.  With an f/2.8 lens on a FF body, the depth of focus is ~160 µm (0.16 mm, 6/1000 in.)
    0.16mm?? How "long" is that?? Can't find that in the ruler... ha ha ha  :o
If you think about it, it's quite amazing that the design and manufacturing technology behind the DSLR... how do you secure the AF sensor and imaging senor in place to such precision even after all the vibration the camera had to go through...

   Have a nice day.

Software & Accessories / Anyone use Zoner Photo Studio 16??
« on: April 09, 2014, 10:08:13 PM »
   I'm looking at lightroom alternative and came across this Zoner Photo Studio 16 ( Look good and price is good (especially you can get a household license). Never heard of this software before and no one seem to be mention it in CR, so just wonder how is it especially compare to lightroom??

   Appreciate if any existing user can feedback.

   Thanks and have a nice day.

The amount of details you can extract of the chroma key backgrounds is incrredible at 4k resolution.

Jokes apart, I second the idea that 4k makes sense for professional videographers either for ultra high def or post production to FHD. However, for consumers, I still doubt that theere is more than bragging rights attachsed tu 4k.

What if you already own a 4K TV, why wouldn't you want to be able to film home stuff in 4K?

Does Sony sell a 4K TV? Yes
Similarly for Panasonic, they make a 4K TV so they're also selling cameras capable of producing 4K.
   4K TV is still very expensive at the moment... Hmm... May be we can do a poll to check how many members in CR had a 4K TV, how many intend to get a 4K TV in one year time and what's the maximum $$$ you willing to paid for a TV??

   Have a nice day.

In another thread on this website, there is a lot of posters from this website that are (or at least were!) absolutely certain that 4K wouldn't take off this year and that Canon wouldn't need to include it in their cameras this year. Seems to me that everyone else thinks that now is the right time to be delivering 4K capability.

If the 7D mark II arrives this year without 4K, Canon will be at the station looking at the caboose as it disappears into the distance...
That really made me smile... and brings up a mental image of Mr. Canon and Mr. Nikon at the train station filming the departing train in 1080 at 30hz, while on the train, the lovely ladies Miss Sony, Miss Panasonic, Miss GoPro, Miss Red, and a host of others are waving goodbye :)

I think I'll go take my GoPro and shoot some 4K video, and when I'm done I'll grab my p/s and try to capture some blue jays in flight at 240hz....
    Then they realized they left all the consumers at the station...  ;D

    Have a nice weekend!

Lenses / Re: Tamron 150-600mm AF servo issues?
« on: March 31, 2014, 08:14:09 AM »
   By the way, the EF400mm F5.6L + kenko 1.4x Teleplus Pro 300 (560mm) reported in my 6D correctly as 560mm @ F8.0, but on the Tamron, it reported 600mm @ F6.3... without the TC.

i don´t get that sentence.
you mean concerning the max aperture for AF?

the 6D will focus with the tamron + 1.4 TC from kenko... but only if contrast is good.
otherwise it´s hunting forever.
    I mean when I use the EF400mm F5.6L with the Kenko 1.4x TC, it'll reported the actual focal length and f-stop correctly to my 6D (560mm @ F8.0), but when use the kenko 1.4x TC with the Tamron, it'll report the focal length and f-stop without the 1.4x... ie 150mm @ F5.0, 400mm @ F5.6, 500mm @ F6.3 and 600mm @ F6.3.... just wonder how the focal length and f-stop reporting work??

   Have a nice day.

Lenses / Re: Tamron 150-600mm AF servo issues?
« on: March 31, 2014, 07:11:27 AM »
   I also just got my Tamron. From my observation for 1 session with my 6D (center point AF), the AF servo once in a while (notice 2 times) will go out of focus a bit on a stationary subject... but I'm not very concern at the moment unless it happen very often.

    Anyway, the result look quite good... 500mm and 600mm @ F6.3 is slightly sharper than mine EF400mm F5.6L + kenko 1.4x Teleplus Pro 300 (560mm) @ F8.0, but EF400mm F5.6L had less vignetting than the Tamron.

   By the way, the EF400mm F5.6L + kenko 1.4x Teleplus Pro 300 (560mm) reported in my 6D correctly as 560mm @ F8.0, but on the Tamron, it reported 600mm @ F6.3... without the TC.

   Have a nice day.

EOS Bodies / Re: 6D Firmware 1.1.4 released
« on: March 20, 2014, 02:05:46 AM »
It seems totally logical that they should have a configuration option that if Logging is turned off, to have the GPS shut off with a custom delay (I would pick 1 hour) after you either shut off the camera switch, or after it auto powers down.  When it powers back up, it starts with the same GPS it had at shutdown, so often it's not far off.  I would gladly live with my first shot or two not perfect rather than a dead battery nearly EVERY time I pick up my camera.

IMO, Canon's GPS implementation is worse than half-assed.  I'm not even sure if it is quarter-assed.  Don't get me wrong, I like having it, but I'd like it a lot better if the people who implemented it had taken the time to do it right instead of saying, "Okay, we have data, ship it."

The 6D's battery has about 13,000 mWh of capacity.  If it is running down in a week, the camera is drawing almost 80 mW continuously.  Given typical GPS power draw, that suggests that the GPS hardware is acquiring fixes pretty much continuously, which is just completely and totally brain damaged, IMO.

In an ideal world, the camera should continue grabbing coordinates normally for a user-controlled period of time after you power it off (15 minutes, by default).  After that period, it should grab coordinates only about once every 45 minutes so that the ephemeris data is always up-to-date, and so that its last known location is close enough to pretty much guarantee a hot start (unless you're in an airplane).

Powering up for a five second GPS fix once every 45 minutes should require very, very little battery power.  Even with some of the worst GPS chipsets, that should take less than 1 mWh per hour.  So by doing a single fix every 45 minutes, a theoretically perfect battery should last for somewhere on the order of 1.5 years in standby mode, not counting any other current draw for writing the data to flash.

Of course, the battery's self-discharge rate would likely run the battery down in less than a year, but that effectively means that the GPS's power consumption should be lost in the noise.

Also, in an ideal world, if GPS coordinates aren't available yet when a photo is taken, the camera should try to retroactively compute the coordinates after it obtains a lock, or at least write the coordinates into the EXIF data of recently taken photos after it obtains a lock, but that's another bug for another day.
    I just disable it (I register it in the quick menu) before I switch off my 6D, so not a big problem.

   Anyway, I only use the 6D's GPS as a backup as it take a long time to obtain an initial lock. Garmin eTrex 30 is a lot faster and can display a custom map...

   Have a nice day.

EOS Bodies / Re: EOS 7D Replacement Mentioned Again [CR1]
« on: March 13, 2014, 09:37:27 AM »
Is AFMA toast?

The 70D is the tip of the iceberg..... it barely scratches the capabilities of Dual Pixel... there are interesting times ahead!

I think this is a correct assessment.  With dual pixel technology, you really don't need AFMA any more.  There is a great article about this in the April edition of "Digital Photo Pro" magazine.
    Or may be an Auto AFMA which you can perform easily in the field... something:
1) You put an AF target at a certain distance and turn on Auto AFMA.
2) AF lock using the traditional PDAF and press the shutter.
3) When the shutter is pressed, the dual-pixel AF kick in to check the AF.
4) The difference will be updated in the camera (or lens) for that lens.

    Have a nice day.


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