July 30, 2014, 11:32:44 AM

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Messages - rs

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1
EOS Bodies - For Stills / Re: Fun Arias rant on APS-C vs. FF
« on: July 29, 2014, 05:57:39 PM »
Zack Arias. Sponsored by Fuji.

2
Lenses / Re: New Canon L Primes, but Not Until 2015 [CR2)
« on: July 28, 2014, 03:32:58 PM »
I'd still  like to see them best Nikon's 12-24.
14-24?

3
PowerShot Cameras / Re: Will the G17 have a 1" sensor?
« on: July 28, 2014, 12:20:27 PM »
That's a pretty neat wish list. However, if true, the lens would be big. It would physically be a 8.9 to 74mm lens, and with the f2.0 aperture at the long end, a 37mm entrance pupil. If that directly translates to the front element size, nothing too massive for a superzoom category camera. That is until you factor in the wide angle (84 degrees) at f1.4, that front element will be big. Possibly much bigger than 37mm.

4
Thanks!

5
Lenses / Re: Canon EF 12-24mm f/2.8 L - Constructing the Enigma
« on: July 25, 2014, 09:10:28 AM »
If it was real and well priced, definitely. But the filter taking abilities and weight position your spec list firmly in the fantasy region of what's physically possible.

6
EOS Bodies / Re: High Megapixel EOS on the Way as Mentioned by Canon
« on: July 23, 2014, 10:15:05 AM »
Unlike many Google translations, this one is a bit more readable...

I note the comment that the 16-35 mk2 was good for APS-H ;-)

The multiple aspheric lens surfaces allow them to ease some of the compromise between reducing distortion and field flatness. The two front lens elements make quite a significant contribution to this and will likely be seen again in new ultra wide zoom designs.

I still want a TS-E14 though ;-)


If the coverage of the TS-E17 is anything to go by, a TS-E14 with any notable shift would be somewhere between huge, expensive and impossible.

Take a look at this to see the effective angle of view of the imaging circle of the TS-E17 compared to a traditional rectilinear 14mm lens (panoramic comparison, near the bottom of the page):

http://www.the-digital-picture.com/Reviews/Canon-TS-E-17mm-f-4-L-Tilt-Shift-Lens-Review.aspx

No scientific fact here, but I'd estimate a TS-E14 with similar levels of shift as the 17 to project an imaging circle with an angle of view something equivalent to a 10mm rectilinear FF lens.

7
Lenses / Re: Sigma 50mm Art 1.4 Focusing problems
« on: July 22, 2014, 11:03:49 AM »
All Sigma lenses have focusing problems! I had two of the a 24-700 and 70-200 last versions - I sent them to be calibrated with my body and then everything was ok.

This is FALSE.  I have two Sigma lenses that have had no focusing problems.  (I don't consider improving AF accuracy with in-camera AFMA to be part of a "problem.")

But the 50 Art that I received did have erratic, unreliable AF that could not be helped with AFMA.

So, if online chatter can lead to Sigma fixing the problem, we aren't helping by using sweeping, ranting statements such as "All Sigma lenses have focusing problems!"

I stated this before and say this again: I did not and do not have AF problems with my 50Art. And I agree with YuengLinger.  It is wrong to make statements like "All Sigma lenses have focusing problems!" - it is not true. Sigma did a great job with the Art series.

+1

My second copy of the Sigma 50/1.4 (non Art) focuses very accurately and consistently. The same can't be said of the first though  ::)

8
Lenses / Re: Sigma 50mm Art 1.4 Focusing problems
« on: July 22, 2014, 07:23:17 AM »
...
But it's annoying to buy a fairly expensive AF lens which you're expected to fiddle around with on a docking station and even then seems best used, in the case of many copies at any rate, in MF mode.
...

Why do you think AFMA exists on Canon cameras? To address the same problem that the docking station is for.

The problem isn't QC it is engineering tolerances and the fact that neither camera nor lens are all made the same. There is copy variation between each camera and lens. This means that whilst AFMA might be +5 for a given lens on your camera, that same lens might be -5 on my camera and that same lens might be +0 on someone else's camera.

Like we've said soo many times before, it's NOT about afma ... Sigh, it's the  inconsistency ! Please print this message and tape it on your fridge.

AFMA is there because there is inconsistency. Canon recognizes that there is inconsistency in camera/lens manufacture and thus introduced that feature to allow people to tune their own camera. If every lens was the same, AFMA wouldn't be needed.

AFMA is there for consistent errors. Inconsistent errors cannot be corrected with a simple offset.

9
Software & Accessories / Re: Help..
« on: July 22, 2014, 02:38:22 AM »
Have you tried extracting the downloaded file, and placing the extracted .fir file on the CF card, as per the instructions in the PDF file?

If that's all there, it won't hurt trying out the firmware update on your friends already updated 7D - it will recognise the update (if done correctly), but will decline the update as it's already on the latest version. If that happens and the same CF card and contents doesn't work in yours, then something fundamentally is wrong.

10
Without images showing the problem, we can only speculate.

My take is it could be some sort of flash sync issue - are you using third party triggers or lighting at or near the x-sync speed?

Again, just pure speculation. Please post some images showing this issue.

11
EOS Bodies / Re: Patent: 45x Zoom for Waterproof Camera
« on: July 20, 2014, 11:49:41 AM »
It's difficult for me to imagine a reason I'd ever buy a gopro.

It's a very focused product aimed at a very different market to the point and shoot alternatives. And it really does depend upon what you do as to whether its way of working is of any use to you. One things for sure - it fills that void of a fisheye portable camera which is waterproof. Just no LCD without spending extra.

At the moment I find I'm using my GoPro more than my DSLR's - but that's down to what I get up to rather than it being a better traditional photographic experience.

12
EOS Bodies / Re: Patent: 45x Zoom for Waterproof Camera
« on: July 20, 2014, 03:23:28 AM »
Stupid.

Want a useful underwater hyperzoom?

Full frame fisheye (180° diagonal) to 100mm.
You can get most of that right now by combining any of the current generation of waterproof compacts with a gopro

13
EOS Bodies / Re: Patent: 45x Zoom for Waterproof Camera
« on: July 19, 2014, 06:02:34 PM »
Is that f9 at the long end?  :o

14
EOS-M / Re: Next official EF-M Lens
« on: July 18, 2014, 09:24:19 AM »
Admittedly I have not looked into Speedboosters but I wonder how they increase stops of lights passing through them? Changing perspective such as what an extender does I get but extenders degrade the amount of light rather than boost it.
A teleconverter enlarges the image projected by the lens. This is much like moving a projecter further away from a projector screen - much of the image is missing from the screen, and even though the quantity of light coming out of the projector is no different, what is on the screen is bigger and dimmer.

Do it the other way only works if you're using a lens designed for a larger format. It telecompresses the light into a smaller imaging circle, producing a brighter, smaller image. Same concept as a projector throwing out too big an image for a screen, so you move it closer.

Obviously using a larger projector screen (read: sensor) in the first place would have captured the same quantity of light, even through the intensity per unit area on the screen (sensor) is lower.

Or a different way of looking at it is the focal length has changed due to a teleconverter or telecompressor, but the physical aperture still has the same diameter. Therefore the aperture ratio (f stop) has to change.

A telecompressor is just a way of using a smaller sensor to do most of what a larger sensor would do with that lens natively. Even though numbers all get shifted around (focal length, aperture ratio, ISO, but not physical aperture or shutter speed), the end result should be the same (presuming the telecompresor ratio is that same as the crop factor, and you tweak all the settings to create equivalence).

15
How about distortion? I really like 0 distortion on the macro lenses. My most used focal lengths are 35,50,70 and 105(which would probably be 135-150 on 70-200 lens).


Here's the distortion at 135 on both lenses:

http://www.the-digital-picture.com/Reviews/Lens-Distortion.aspx?Lens=687&Camera=453&FLI=2&LensComp=404&CameraComp=453&FLIComp=2

And a comparison of the mk II at 135 and the 135/2:

http://www.the-digital-picture.com/Reviews/Lens-Distortion.aspx?FLI=2&FLIComp=0&Lens=687&Camera=453&LensComp=108

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