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Messages - GMCPhotographics

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31
Lenses / Re: Canon EF 11-24 f/2.8L Coming [CR1]
« on: August 18, 2014, 05:31:57 AM »
Dear Friends.
Sorry, I do not want to spend $ 2800 US Dollars for this  new Great/ Super Sharp , Canon EF 11-24 L 2.8, Because I already have  Good Rokinon 12 MM F/ 2.0, <snip>

1. We're not offended by your choice of lenses, you don't need to apologize.

2. It seems you have a crop camera, so it's expected you would be uninterested in an expensive FF UWA zoom.

Thanks, Dear Friend Mr. Antono Refa.

You're welcome, dear buddy.

Well, I have Both FF and Crop Frame Canon Cameras

Then, as you probably know, there are hardly any rectilinear lenses wider than 16mm. If you're not willing to spend $2,800 on one of those few, that's your choice, no need to say you're sorry.

[I wouldn't spend $2,800 on this lens, if released, but I will wait patiently for a price drop.]

THANKSSS, Dear friend Mr.
I am lower level in Technical Know How of Photography , The Stupid question is "  there are hardly any rectilinear lenses wider than 16mm. "= What is  rectilinear Lens ? = The Distortion at the edges of the photos ?
I am fast learner, and Want to learn the new thing in every days.
Have a great Sunday, Sir.
Surapon

Rectilinear = a wide angle lens which is not a fish eye. They aim to render straight lines perfectly straight, even at the edge of the frame. If you were to fill the frame with a flat subject (eg a test chart) it would be capable of taking a distortion free image of it if lined up perfectly.

Rectilinear lenses do suffer from other forms of distortion which fisheyes (especially stereographic fisheyes) are less susceptible to - any subject which is three dimensional really. Take a group photo for example - people near the edges of the frame are stretched. Anything in the corners looks even more extreme. Even photos of innocent stuff like grass filing the bottom half of the frame and sky in the top - the details in the grass blades will take on the characteristic stretch into the corners, as will any clouds.

The wider the rectilinear lens, the more pronounced this effect will be. In certain scenarios it can be something to be embraced (although not group shots!)

Yes you are correct, a fully rectilinear corrected lens is one where straight lines stay straight in the frame. Two good examples of this are the 14L and Sigma 12-24 HSM (mkI). Circles become more egg shaped as the approach the corners of the frame. All wide lenses show distortion somewhere, either lines or circles.

Most rectilinear wide lenses are corrected to some degree but not fully. This is to allow a compromise and versatility. A fully corrected lens distorts circles (faces) so a design compromises is employed to keep straight lines fairly straight (a slight curve is usually not too noticeable and quite acceptable) but keeps the circles fairly circular (unless you shoot up close). The 16-35IIL is a great example of this. Most lens designers assume the user will correct in Lightroom / Photoshop if they need a more extreme correction. I find the look I get out of the 16-35IIL looks quite natural and is kind on the eye. A 14L, TS-e 17L or Siggi 12-24 tend to look very angular and isn't how the human eye sees the scene.

Where as fish-eye lenses are the complete opposite. Circles stay circular but straight lines curve as they approach the edges of the frame.

This is why I have more than one wide lens in my collection and why I am REALLY looking forwards to this new lens from Canon. It could be a game changer.

32
EOS Bodies - For Stills / Re: Canon 5D Mark III Pain Smearing
« on: August 18, 2014, 05:07:23 AM »
HI

I wonder if anyone has experienced this problem.   I have a 5D mk III and it's about 2 years old.  recently I was in holiday in Vancouver and the weather was warm but not too hot; however the white paint on the Canon logo at the front of the camera has started to run and smudge over the front of the camera.   It doesn't affect the camera operation but it looks cheap and nasty.

The camera is going back to Canon next week, however i am curious if anyone else has had this problem.

Thanks

I have two 5DIII's and a single 5DII, all bought a year apart. I've used them quite heavily in a professional capacity, shooting a lot of weddings and I've not had this issue. But it wouldn't surprise me if Canon had a rogue batch. Stuff on the production line some times goes out of spec due to suppliers supplying out of spec paint.

33
Lenses / Re: Canon EF 11-24 f/2.8L Coming [CR1]
« on: August 09, 2014, 07:44:58 PM »
I hope this lens isn't rumour/vapour ware...but if it's true and lets face it a 14-24mm f2.8 isn't that much wider than current 16-35mm f2.8 and sacrifices the long end, a very useful 35mm...then it really needs to offer something more. I was hoping for a 12-24mm, but I'd gladly take an 11mm at the wide end!
I used to have a Sigma 12-24mm f5.6 (ok read f11-f16 due to vignetting) but the angle of view on a full frame camera was amazing and a lot of fun.
I can't wait...but happy to as long as Canon get this lens optically right!

34
Third Party Manufacturers / Re: Review: Zeiss 135mm f/2 APO Sonnar T*
« on: July 26, 2014, 03:33:34 PM »
The test shot at f2 on the Canon is clearly slightly back focused and therefore not a fair example. It makes the Canon look softer than it really is.

35
Lenses / Re: What Lenses are missing from Canon's range
« on: July 17, 2014, 09:01:47 AM »
Need to have: 85/1.4 (but no one else mentioned it, so I suppose Canon has little market for it... :(
Want to have: 135/1.8-2 IS (that will essentially lock my 70-200 II to non-travel use)
Would be nice to have: 12orwhatever-24/2.8

I am not sure any of these will come out this year though... :(

If canon releases a 135 f1.8 LIS, I would get one and swap out my 70-200 f2.8 LIS II for an f4. I would use the prime for the dark stuff and the f4 for the bright stuff. I wouldn't need to lug the big 2.8 about anymore.

36
Lenses / Re: What Lenses are missing from Canon's range
« on: July 17, 2014, 08:59:18 AM »
One more vote for the 14-24 f/2.8 and the 135 f1.8 IS

I would rather a 12-24mm f2.8 and a 135 f1.8 LIS. A 14-24mm is only 2mm wider than a 16-35 and looses a major focal point at the long end.

37
Lenses / Re: Canon EF 100-400 f/4.5-5.6L IS II [CR1]
« on: July 14, 2014, 05:29:26 AM »
We all know why the new lens will have a rotating zoom ring / extending barrel (aka 70-300L) instead of the current push pull: Video....
You can't fit a pull focus unit on a 15mm rail system where a lens can extend so much with the focus ring on the extending barrel. Where as, you can with the other design style.
There's another advantage too, the curent design pushes the centre of balance way forwards and the tripod collar is right at the back of this lens towards the rear mount. Hopefully the newer design will address this.

38
I think it depends on your needs. If you do portraits or weddings, you might need a fast 2.8 lens. If you do landscapes, travel or hiking/outdoor photography, the light-weight F4 lens would be a better choice for me.

I have a F2.8 and often wish I had instead purchased the F4.

Yep, I had the f4 version for a while and I've had the f2.8 version for some time too. So for a while I had both. I bought the f4 for travelling and in that context, it was perfect. It was also far easier to use for close up work too, eg rocks, details and larger flowers. In this context it was better and sharper than the f2.8 and a lot easier to handle on a tripod. If I was going to buy again, I'd probably get the 70-300L instead. but to be honest, there isn't any losers here, all three lenses are top tier and we really are splitting hairs between them. There has never been so much top end choice as we have available to us these days.

39
Lenses / Re: Canon EF 100-400 f/4.5-5.6L IS II [CR1]
« on: July 13, 2014, 02:26:12 PM »
Wow....the unicorn rides again....it's gotta be released at SOME point...I just worry I'll be too old by then!

40
Lenses / Re: Sigma 50mm Art 1.4 Focusing problems
« on: July 11, 2014, 11:23:27 AM »
A short update:

I got my 50A back from the shop, and lo and behold, the inconsistency was gone. Sigma representative said they adjusted the lens to a standard body, and then returned it. Now the lens was back focusing either when approached from INF or MFD, which is OK from my books as I've tools to correct that. So Sigma dock it is, and 20 mins of adjustments later, I was ready for real life testing.

In the 300 photos I took last evening, I didn't see focus errors, and got a very good keeper ratio. The lens is now working, and actually seems to be sharp enough that I actually need to decrease camera sharpening preset for JPEGs.

EDIT: I'll have to say that this lens rocks! The background blur stopped down is a definite improvement over Canon's 50/1.4!

Yep, it's great idea of Sigma's...make an expensive device to get customers to do their work for them.
You pay Sigma to spend you time correcting their sloppy manufacturing errors. Maybe Ford should make cars which only drive properly after you buy their laptop software to interface with it....

41
Lenses / Re: Waiting for the 35 1.4L II
« on: July 11, 2014, 10:56:03 AM »
I think I'm slightly mis-representing my position on this lens...the 35L is a great lens. It's faithfully provided great service for me over the years. The new one will need to provide this and more to replace my existing lens, which has proved itself many times.

42
I have owned both and I wouldn't choose between them based on IQ.  I would make your decision on the following:

Is the big difference in size, weight, and price worth it for:
- 1 extra stop of light (do you shoot sports/wildlife in low light?)
- shallower DOF (both have great bokeh, but f/2.8 is better for subject isolation - though f/4 at 150-200mm provides plenty shallow DOF for most purposes including portraits)
- somewhat tougher (all metal vs. excellent engineering plastic) build quality
- a tripod ring in the box (though the f/4 IS + way overpriced Canon ring is still much cheaper than the f/2.8 IS II)
-AF with the 2xIII extender on all bodies

For me, it is, but if I traveled much at all or didn't need the low light speed of f/2.8, I'd go back to the f/4 IS.

What Mackguyver said....spot on with my findings too!
Just to add, I think any difference between lenses (f2.8 vs f4) is more likely to be copy variation than any measurable statistic. In real world use they are optically and pertty much mechanically equal, except for the lesser build on the f4. 

43
Any one here having tested both the new 300mm F2.8 L IS II and the new Sigma 120-300mm f/2.8 AF APO EX DG OS HSM and having an opinion on how these two said lenses compare in sharpness and general (real world) usability ... Some reviews Rate the sigma as sharper as the Canon 70-200mm F2.8 IS II so it should be really sharp ...   

Yes the Sigma is sharp, but not quite as sharp as the the Canon prime. But there are a few things you should be aware of the Sigma 120-300 f2.8 OS which rarely comes up.
1) it's AF is not in the same league as the ef 300mm f2.8 LIS or 70-200 f2.8 LIS II lenses, not even close. It's slower, less accurate and more ponderous. It often locks on and then looses AF just as quick. AI servo with this lens using 61point AF on a 5DIII was particaulrly bad, as was 19 point AI servo on a 7D. Add a teleconverter and this gets a lot worse.
2) The lens drops focal length dramatically as the focus point gets closer to Min Focus distance. While this may not appear to be an issue, it is if you are trying to blur the background using close focus and wide open aperture. In this respect, the Canon prime is way way better, great for animal or people portraits. From my findings, the Sigma drops to about 240mm at 5 meters...which gives worse results to the 70-200 f2.8 at 1.5m at 200mm. In short, both the 70-200 II L and 300 f2.8 LIS are better at melting background and makes my wonder if the Sigma is worth the effort.
3) The Sigma is a lot heavier and larger than it needs to be. Don't confuse weight / mass with quality! The hood is terrible and the tripod ring isn't anyhwere near to the engineering of the Canon versions.

44
EOS Bodies / Re: 5DIII CF vs SD slot performance?
« on: July 11, 2014, 06:50:05 AM »
Yep, with my cards, I get only 5-6 bursts out of the SD card and I get about 10-12 from the CF card. Interestingly, if I have the Sd card slot enabled (regarlessly of having a card in there) I get the lower buffer / card write times. So when I need to shoot fast and long, I take out the SD card and use the Q button to write to the CF card only.

That's odd, I have noticed no such issue. My settings are set to record to both, and when either CF or SD isn't present, it'll give a warning when you turn on the camera, but I don't notice it negatively effecting speed.

It's not the speed, it's the buffer capacity it effects. With the right setting, the Cf card can shoot, buffer and write which frees up more shooting time until the write speed craps out and the buffer fills. With the SD card (raw to CF and Jpeg to CD) the card can't write that fast and the buffer fills up very fast which then stops the shooting.

45
Lenses / Re: Waiting for the 35 1.4L II
« on: July 11, 2014, 06:46:55 AM »
No doubt, sigma 35mm 1.4 art is canon killer.

Check some reviews, many people compared the two lenses. Though I'm not quite sure about the build quality that Sigma provides — at first sight yes, it's very good, but will it last as canon 35mm does?

I'm not sure I'd call it a Canon killer....it's a little bit sharper but that's about it. Also bare in mind that I've been using my 35L for the last 8 years (and it's paid for itself time and time with great professional images) where as this Sigma is new to the market. I'm happy with my 35L and see very little reason to swap to the Sigma. My Canon 35L has provided great images and will continue to do so.
If you rate a lens by optics alone then sure the Sigma looks great. But I would wager in a comparison that few could tell from an A3 print which lens was which. The Canon is far better built, has a far more reliable AF system and will hold it's value on the second hand market over the long term. Sigma AF issues are well documented, even their 120-300 has af issues.

You're wrong about build quality, the Sigma is much better, all of my 35 L's has been squeaky when squeezing the sides of the barrel, and two of them had the small plastic pins that holds the af/mf switch in place broken, leaving an open hole right into the lens.

 But color and contrast, build and ca correction needs a BIG update.

Don't mistake engineering plastic as weak and fragile. Sure the 24IIL is a lot more robust in how it feels in the hand and the shell doesn't flex. But after 8 years of heavy professional use, it's never failed me and still looks as good today as the day i bought it...although the hood is looking a bit worn. Most Sigma's I've bought and used in the past (the old painted matt finish and earlier) have looked terrible after a year or so. My old Sigma 12-24mm lens was solidly made from metal and yet had to go back to Sigma 3 times over 10 years due to a number of mechanical and electrical issues. First the Aperture motor burnt out, amazing considering how little I used this lens. Then one of the internal lens groups became free of their housings and acted like a marble in a cup. Then for some reason the lens started to mechanically vignette at all focal lengths...it had to go back for a re-build. If I compare that to my 16-35IIL which has been used in far more inhospitable environments and used a lot more...i've had no problems with it at all. I sent it into Canon last year becuase of a scratched front element (it was effecting my sun star shots) but that was my fault not Canon's.

While I'm sure the Sigma operates well, looks and feels good and delivers great results....I am very shy of Sigma. My fingers have really been burnt a lot by that company and I'm not sure I want to risk them again.


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