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Messages - GMCPhotographics

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361
Other than the OS (Canon IS), I don't see the sigma being a challenger of any sort.
Who knows, though?


The Canon design is an ancient design with blurry corners and a blurry mid-frame. It's not a top of the line lens. It also has severe issues with purple fringing that's very poorly controlled, and as a long lens , lacking image stabilization means if you're just shooting an event or  you're wasting 1-2 stops of light just to counteract camera shake without making your subject any sharper.

Here's a comparison between the 135mm f/2.0 and a much sharper lens:

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=458&Camera=453&Sample=0&FLI=0&API=0&LensComp=108&CameraComp=0&FLIComp=0&APIComp=0

f/1.8 also makes a difference is subject isolation, and also reduces noise too.

Everyone was saying that you couldn't improve on the 35mm f/1.4 before and look what happened. The problem is that people assume a "good" lens can't be replaced by something that is earth shatteringly better.


My old 200mm f2.8 II L was the sharpest prime I have ever used. It was a sublime lens. But I sold it because my 70-200 f2.8 II L IS was nearly as sharp but a lot more versatile. My 135L is sharp and yes it gets a bit of purple fringing....but Lightroom deals with this so well that it's a non issue. My 85mm f1.2 II L is a tad sharper. No one ever believes me when i say this, which I think is an opinion which goes against common forum mantra. But my copy is. My 135L is a stellar performer and I get great result out of it and I use it wide open often.
But it's a an old design and things have moved on. There's a possible 1/3 stop of brightness which can be extracted from the front filter size. IS could easily be added. AF could be tweeked. Newer coatings to help cleaning and flare control. More aperture blades and rounded ones would help the bokeh a bit. It's not weather sealed and mine's been back to Canon a few times for a loose front collar. The Hood is huge and it's flare control isn't as good as other lenses.
It's a bit like the 35mm f1.4, a brilliant lens. But just needs a little update to bring it up to epic status. 

362
EOS Bodies / Re: *UPDATE* A Bit of EOS 70D Info [CR1-CR2]
« on: April 22, 2013, 09:45:43 AM »
Jrista
search : John Sheehy 7d aa-filter and you get answer

this is from dpreview, 3 aps and  the 7d , 7d has a stronger aa-filter like Nikon often have before  compared to for example  Pentax APS who use the same sensor as Nikon but lighter filter, d7100 has no filter and the resolution is also higher

I personally found my 7D to produce slightly soft per pixel detail when compared to my 5DII/III. I've read that Canon used a stonger than usual AA filter to reduce moire in movie mode. It was a very nice camera to use, but it's IQ wasn't on par with Canon's full frame offerings. It had very high iso noise, slightly odd micro contrast and the pixels were softer than any other DSLR I've used. I loved the 8fps, very capable AF system and great handling.


dpreview resolution test shows 2600 LPH for the rebel   and 2500 LPH for the 7d

Lets qualify things here. The 7D has a "stronger" AA-filter than the 650D, 60D, and D7100. STRONGER THAN X. I need to be extremely clear here that having a "stronger" AA filter than any one of those cameras by no means indicates the 7D has a TOO STRONG AA filter. The sentiment that you were pushing was that the 7D is losing IQ because of it's AA filter, an AA filter that is "too strong".

I strongly dispute that notion. When it comes to digital photography, we want an AA filter to be ideally suited for the specific sensor you are using. You don't want it to be too strong, and neither do you want it to be too weak, ESPECIALLY if you shoot anything that might produce aliasing or moire. Aliasing and moire are BAD things...and in your example shot, the 7D image is the ONLY one that looks acceptable to me...it reproduces the information present in the subject being photographed better than all the others. It should also be noted that the softening caused by an OLPF is predictable softening, while it eliminates an unpredictable outcome...moire. Softening is global, and thus something we can easily correct in post with a little bit of sharpening. Correcting moire is a far more difficult task, and it must be performed locally rather than globally, only to regions actually affected by it. The concept here is no different than diffraction...stopping down to gain necessary DOF is preferred over shooting wide and ending up with a thin DOF. Correcting for diffraction in post is easy because it is global and linear, correcting for an improper DOF is practically impossible because it is localized and non-linear.

I believe my 100% crop photo of the orange-morph house finch....a bird, with lots of criss-crossing feathers and color detail...looks nearly perfect! No moire at all, no aliasing, however the detail level is exquisite. The 7D has neither a too-weak nor a too-strong AA filter. It has an AA filter that is just about PERFECT for an 18mp APS-C sensor with a 4.3┬Ám pitch.

I stand by my statement. The notion that IQ on the 7D is lost because of an AA filter that is too strong is a myth.

363
Have to respectfully disagree. An inferior lens manufacturer would make lenses other than what Canon offers so as to offer no apples to apples comparisons. Sigma is making (so far in their art line) superior lenses in critical flavors that go head to head with the best that Canon has...

There's only one superior lens in their art range at the moment, the 35mm f1.4. But like many Sigma lenses before, how well does it focus? The rest of Sigma's range are sub par with Canon counter parts. With Sigma, you get what you pay for.

You are terribly misinformed. The new 35mm focuses like a dream. And the USB dock has been designed to counter possible tricks by Canon in the future.

And the statement in red is plainly false.

Ok, lets qualify this a bit more. I've owned a Sigma 180 macro and used several, the AF ring was so gritty it was difficult to fine tune the focus. When compared with a Canon 180 L, there was  amassive focal length difference between these two lenses. The Canon has a much longer focal length at close distances and I'm pretty sure the Sigma lost focal length as I focssed closer....not what I wanted in a Macro lens. I had a 100-300 f4 EX DG...it was pretty unspectacular in sharpness, but more seriously it's AF was pretty inaccurate, often mis focussing. It had the most stupidly huge hood...because it flared so badly in bright light. I had a 70-200 ED DG mkI, it had dreadful back focussing issues at Min Focus distance. It had AF inconsistencies, sometime accurate and sometime way off. I have a 12-24mm EX DG. A nice lens, but it's been back to Sigma twice. Once for Aperture motor burnout and a whole lens group coming loose. I had a Sigma 120-300 OS DG and to be frank it was terrible. It was sharp enough, but it was so huge. It's AF was erratic and imprecise. It was way short of the 300mm stated, closer to 280mm at infinity but down to a dissapointing 240mm at Min focus distance. When compared to my Canon 70-200 f2.8 L IS II, the small increase in Focal length wasn't worth the poor AF and massive extra bulk. None of these AF issues were related to Microfocus, the Sigma HSM motor system just isn't in the same league as the Canon USM system. I had a Sigma 24-70 (non HSM), it was a noisy AF system, but very good. The big issue was the rubbish hood and awful flare on sunny days. When I replaced it with the Canon 24-70L (mk I) it blew it away in every regard. Generally I find that Sigma lenses have a warm cast, but this varies between lens designs.
I hear from several friends who have the Sigma 50mm f1.4 and 85mm f1.4, they too get focus inconsitencies.
I don't get these issues with Canon L lenses. After the 120-300 OS DG dissapointment, I bought a 400mm f2.8 L IS which really put the Siggi in it's place. It's not just the sharpness, it's the AF's amazing accuracy.
So I'm sure you see that I have a long history with Sigma lenses in a professional basis. Most of my lenses went back to sigma and couldn't be fixed.

I'm all ears for Sigma releasing newer better lenses, but I've heared this story SO many times. I trust in Canon because they make reassuringly good kit and their prices reflect this. As I said before, and i'll restate again....the only superior lens (to Canon) in their catalogue at the moment is the 35mm f1.4. Every other lens is in some way deficient compared to it's Canon counter part.

364
Have to respectfully disagree. An inferior lens manufacturer would make lenses other than what Canon offers so as to offer no apples to apples comparisons. Sigma is making (so far in their art line) superior lenses in critical flavors that go head to head with the best that Canon has...

There's only one superior lens in their art range at the moment, the 35mm f1.4. But like many Sigma lenses before, how well does it focus? The rest of Sigma's range are sub par with Canon counter parts. With Sigma, you get what you pay for.

365
Maybe this means that a Sigma spy within Canon has gleaned that they won't be adding IS to the 135L anytime soon.

If it's as good as their Art 35 and the AF is close to the 135L then I'd certainly consider it.

Canon's probably already scrambling to get a 35L II out the door to catch up with Sigma...  An Art 135 OS and 50mm would really hit Canon where it hurts.

The Canon ef primes have been a nice earner for Canon. Many wedding photographers have stayed in the Canon fold (when Nikon had better DSLR specs) becuase of the 35L, 85L and 135L. No other band (other than Sony) had a simular array of bright primes. But as usual Canon were unaware of the need to develop the next gen of fast primes. The 35L is a fantastic lens, but flare control isn't great, it's AF in low light is erratic and it's not weather sealed and it's number of aperture blades is an even number. The 135L is an awsome lens, but it's an old design, flare could be better, MFD could be better. It could do with newer coatings, it's aperture blades are not circular (stop down and look at the out of focus blobs). It's not weather sealed and Sony has an f1.8 variant, which means that it's not the best of the breed. Popping IS on it would really make my wedding work easier too. It's AF is good but not as good as the newer 70-200 f2.8 L IS II. It#s a great lens but there's quite a lot of room for improvement.
The 85L is a quirky lens and I'm quite happy with it as it is. It's not easy to use, and it's dof is so slim it requires a well honed AF technique to get consistent results. I use this lens a lot and I love it.

366
EOS Bodies / Re: *UPDATE* A Bit of EOS 70D Info [CR1-CR2]
« on: April 19, 2013, 06:53:56 AM »
"Plus, you've just acknowledged that the 5DIII's autofocus and low light performance is second only to Canon's most ultimate ever flagship camera. And yet it's still an insignificant marginal improvement over the 5DII? Please. At least have the decency to keep your trolling consistent...."

The 5DIII's AF capabilities are a vast improvement over the 5DII. It's the same basic system as the 1Dx but with out the face recognition and colour tracking abilities. But the AF array and circuitry is the same. I regularly use a 5DII and 5DIII alongside each other at weddings. The 5DII's centre spot is the only usable AF spot and it's pretty good. But as the light levels drop it starts to fail. The 5DIII's AF array is extensive and most of those spots are slightly better than the centre 5DII spot. The middle vertical 5 spots on the 5DIII are amazing and can lock on in REALLY low light levels, which the 5DII can only dream of. The 6D's AF array is new but low in AP points. Again the centre spot is the really usefull spot here and in low light it's better than the central 5 spots on the 5DIII and 1Dx.
The 1Dx's AF is slightly better that the 5DIII where AF Servo mode is employed, but not a huge improvement.
In One Shot mode, there is no difference between the 1Dx and 5DIII's AF abilities. The 1Dx's big ability is that crazy fast card eating fps and buffer size.

367
EOS Bodies / Re: DxOMark Sensor Performance: Nikon vs. Canon
« on: April 19, 2013, 06:34:03 AM »
nice side by side (literally) comparison between D600 and 5Dmk3: http://youtu.be/Ot7aMeUmojY


Eyes roll....wow a guy with a video camera, web access and a pair of DSLR's....claiming to make an informed review.

Ok...here we go...he compares a 5DIII size against a D600....where the 5DIII has the optional grip...hullo?
Then makes a further eyes roll statement....the Nikon has dual SD card slots...which Canon doesn't have...when ever has an SD card been a cool thing compared to Compact Flash???
The Nikon has a pop up flash.....OH COME ON.....5 mins of my life wasted on this muppet.....

368
EOS Bodies / Re: *UPDATE* A Bit of EOS 70D Info [CR1-CR2]
« on: April 19, 2013, 05:45:20 AM »
You are right and you are  wrong, the APS has a break point in low light and if you compare that with a 24x36mm area  it is around 800iso
second, it is the surface size who are important, not the pixel size, if we not are discussing very low light. and the results should be seen / compared at the same size.
third, APS are earlier in the development stage , it means better QE, etc than the 24x36mm sensor who are last in the chain because of costs and machines

read more here http://theory.uchicago.edu/~ejm/pix/20d/tests/noise/noise-p3.html

ps : smaller pixels results in less noise


From my limited understanding of pixel / sensor design is that the pixel etchines are all physically the same size on all of Canon DSLR cameras. Every pixel is pretty much the same. but the bucket or well which they sit in in varies in size. On top of this arrangement is a microlens which helps direct as much of the light from the bucket surface into the smaller pixel at the bottom of the hole. Which is why Canon and Nikon made such a fuss over their gapless microlenses. Canon haven't made 
much advancement to their pixel design for a very long time because they were using the microlenses to mop up more or less light as required in their design brief. Nikon went a bit crazy and added gapless microlenses in their D700/D3. Keeping their mp low at 12mp, meant that they had a real advantage over the same generation of CAnon cameras. But it was a one off advantage and one which wouldn't be sustainable in future products as their MP increases. Canon's idea was far better and offered future scalability in MP. Then Nikon proved this point and released the most barmy camera ever...the D800, which created confusion in their product range. No one wanted an ultra high MP camera riddled with iso noise. The D700 was snapped up by pros who saw a big iso and AF advantage over Canon...but within one generation have been soarly let down by their new chosen brand. When I look through their camera portfolio, there's nothing there that inspires me. When I look at the Canon camera portfolio...it's looking very strong. The 6D is sweet, the 5DIII is amazing and the 1Dx is probably the best DSLR ever made. 

369
Software & Accessories / Re: Wonderpana System from Fotodiox
« on: April 16, 2013, 04:49:24 AM »
Oh I know the 17TSE wasn't made for that, but I have done it a few times shifted down in a bright room where I didn't have to get it perfect. No handheld tilt, though... I will have to take a look at the Fotodiox rig.

Did you see the site/blog run by a German photographer of architecture who bought a second 17TSE lens cap and made a filter holder out of that?
I found the URL in my OneNote files:
http://digidaan.wordpress.com/2010/05/31/polariser-on-17mm-tiltshift/

very interesting blog.


Yes, that particular mod has been around for a while. It's Ok, but the filter isn't quite big enough to cover the whole tilt and shift range. The WondaPana system is currently the only system which allows full movements with a single filter.

370
EOS Bodies / Re: A Bit of EOS 70D Info [CR1-CR2]
« on: April 16, 2013, 04:36:23 AM »
The problem is not the megapixel number, just that Canon is using technology from 2009 in a world of Moore's Law.

That's like Apple sticking with the camera from the 3GS for the iPhone 5.

18MP is the sweet spot?  So when camera comes out with a 24MP sensor with better DR and ISO than this 2009 relic, what will you do then?  Stick with your 7D because "no one needs those megapixels"? 

An 8MP cellphone sensor with tiny plastic optics can out-resolve a 5MP one.  Do you know what a DSLR sensor would be like at that density?  There is a ton of growing room, 18MP is just the beginning.

I think the question one should be asking is "what am I going to use this camera for?". Does 15% or 25% more resolution (which the lenses are unlikely to be able to capitalise on) make you a better photographer? The major dofference between a 60D and 70D is the GPS and wifi, not the sensor. If Nikon or Sony have a bigger megapixel camera available which has the same or better iso ability (which I seriously doubt), will it be able to get better pictures or print much bigger? Or is it about bragging rights and owning a camera with the highest MP rating?

I'm a professional photographer and I'm really happy with the resolution on my 5DIII and 5DII. My landscapes are sharp at 100% and I can enlarge upto A1+ using my big Epson printer. The prints are crisp and sharp close up. When I had a 7D, I was happy with it's resolution too...it's just that the iso ability of that camera was seriously lacking. Iso 400was as high as I'd push that particular camera. It was a great camera bit the IQ wasn't that great. I hope that the next gen of 1.6x crop sensors from Canon can match the last gen full frame sensors for ISO ability and general pixel quality. Then they will have another winner on their hands.

371
EOS Bodies / Re: Patent: EF 400 f/4 DO IS II
« on: April 16, 2013, 04:25:24 AM »
The cost of the 1200mm, like the cost of all the other supertele primes, is all about the amount of glass.

Glass is melted sand. Glass is cheap -- even cheaper than a silicon wafer. Even fluorite is cheap and abundant.

What costs money is first the R&D; even Canon's very intelligent and skilled and very well paid engineers with all the equipment they might want at their disposal haven't yet truly figured out DO in the first place.

And what next costs money is the tooling. So you've got a bag of sand. How are you going to sinter it with the right trace elements into a bubble-free block the size you need? How're you going to grind that into the shape you need to the tolerances you need? How're you going to make however many thousands of these elements you need for the lenses you're going to sell, and where're you going to keep the individual machinery you're going to need for each different element? Or, how're you going to make a general-purpose lens manufacturing machine that can handle a broad range of the very different elements you need?

And let's not forget the housing, autofocus motors, IS gyros, and circuitry / firmware -- very little of which can be reused from lens to lens, especially with the big exotics.

Now, take the cost to make all the machinery -- again, the materials are a rounding error -- and divide by the number of lenses you expect to sell. Add in all the salaries you have to pay, all the taxes, all the shipping, all the environmental cleanup fees, all the rent, and a few pennies for the shareholders.

If you're going to sell lots of these lenses, you can spread that huge cost over all of them and wind up with a rather modest sale price.

But if you're only going to sell a few thousand, as I expect is the case with the Great Whites, then you have to make each buyer pay through the nose to offset all of that.

Think about it for a moment.

Do you really think that a 1200 is as expensive to make on a per-lens basis as an exotic luxury sports sedan? Or that a 400 f/2.8 costs more to make than an econobox?

No -- of course not!

But the sales volume is so low for the lenses....

Cheers,

b&

I love the way so many "lens experts" come out of the woodwork on camera forums...have you hand grinded any of your own optics??? Have you designed your own lenses and popped them on a camera? No...I haven't either.
According to various websites, the optics for the legendary ef 1200mm f5.6 were taken from the stock of FD 1200mm f5.6 lenses that Canon had. They made a new set of EF lenses, bu the optics were taken out of existing lenses. Canon haven't ground any EF front optics which is bigger than the current range of big whites (400/2.8, 600/f4, 800/5.6). Which leaves one to wonder if they no longer have that capability or they outsourced the original FD lens optics, which would explain why it's so darn expensive! It would also explain why Canon raided their old FD lenses to make only a handfull of the EF variants.

372
Software & Accessories / Re: Wonderpana System from Fotodiox
« on: April 15, 2013, 08:30:36 AM »
GMC,
To confirm: your CPL is from this Fotodiox system and is used with their holder arrangement? It's optically good enough?

I have the 17 and use it mostly inside but have been reading about various solutions for getting something out in from of the "dome". Agree about the half-ND stuff although for some travel situations it was good to have the hand-holding half grad solution available.

...not hand holding the 17 too much... have done, though. <grin>

Yes I have a CPL from Photodiox and is used in their holder. It's fine, simular in quality and polarising strength as a Hoya or Lee unit. Not quite as good as the Heliopan CPL's I'm currently using on my 16-35IIL. But their CPL is the best I've tried so far.

The TS-e 17L isn't really an hand held type of lens. The wide angle of view needs more meticulous care when adjusting the movements than other TS-e lenses. It's really a tripod only lens, so ND grads aren't very appropriate with this lens.

373
Agreed, but to say the 85L II is sharper than the 135L is stretch. Even though we're comparing razors to razors.

I can only state what my particular lenses show. My 85IIL is a bit sharper than my 135L. Both are sharp, no argument! My 135L is about as sharp as my 70-200 f2.8 L IS II.
But my sharpest lens is easily my 400 f2.8 L IS and then my 100 LIS Macro. Both of these lenses are bonkers sharp. My old 100mm USM macro was sharp but not as sharp as my L version, other people used to rave about theirs, mine was a little so-so.

374
nice, I have them also, but DXO means that the sigma 85mm is better than my Canon 85/1.2mk2, and cheaper.
what to do?what to do?

The sigma 85mm does not render better than the 85L II. It just doesn't.

I didnt say that, I say that DXO gives the Sigma lens higher score than 85/1,2 mk2

There is more to a lens that just a score.  ;)

Their 85IIL must have been seriously out of spec and shows just how laughable DXO testing really is. My copy (which I use wide open all the time) is sharper than my 135IIL and 70-200 f2.8 L IS II. It's a stunning optic. I've tried the Sigma, it's was nice but not in the Canon league. It's Focussing was erratic and the images just don't look as nice....plus it's not quite as bright and certainly not as well built. The Canon 85IIL is an engineering masterpiece. My copy is now 5 years old and still looks new and it's had a hard life....good luck with your Sigma in that regard. I've had a lot of Sigma glass over the years and I've completely lost faith in the brand.

375
Lenses / Re: New Tilt-Shift Lenses in 2013 [CR2]
« on: April 12, 2013, 10:26:45 AM »
WHEN!!! It's now 2013, any more news on when? what month? I need these lenses now, and don't want to rent anymore, and don't want to buy, just to have the new one come out a week later.
Why not just buy them, and then sell them later when the new one comes out? Just consider it an extended rental period with an up-front deposit...

TS-e 45 and 90's are very reasonable on the S/H market. Look for mint copies and you'll sell them for what you paid for them...essentially, it'll be free use for the time you have them.

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