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Messages - mb66energy

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166
Lenses / Re: Another Mention of a New Macro Lens in 2014 [CR1]
« on: February 13, 2014, 12:04:46 PM »

All internally focusing lenses do this by shortening their focal length. If you go all the way to 1:1 macro, your focal length would be cut in half. This means your beautiful 200mm macro lens with internal focusing would turn into an 100mm macro lens at 1:1 magnification. Pretty pointless, isn't it?

The distance between image plane and object is 4 times the focal length at 1:1 or otherwise: the focus distance at 1:1 will give you the focal length if you divide it by four:

EF-S 60    MFD 200mm        Calculated Focal length at 1:1   50mm
EF 100     MFD 300mm        Calculated Focal length at 1:1   75mm
EF 180     MFD 480mm        Calculated Focal length at 1:1   120mm

Ok, it is not a true "single lens" but there is a good chance that you do not loose 50 % of the initial
focal length.
Modern lenses bend the light by crazy ways so there is a chance that you simulate lens positions to get
1:1 without loosing any focal length. Think about EF-S10-22 at 10mm which leaves 35mm space between back lens and image plane!

167
Lenses / Re: Another Mention of a New Macro Lens in 2014 [CR1]
« on: February 13, 2014, 11:46:57 AM »

It would be expensive and it would sound like a very cool lens...but it would be mostly a marketing gimmick. You'd think tilt would let you achieve an apparently deeper DoF for macro shooting, right?  Well...it would, but the amount of tilt required increases with magnification.  I think you'd need 30° of tilt or more, meaning a truly massive image circle would be needed, and even then the optical quality would suffer with such extreme tilt.

I don't think so because the lens is usually tilted around an axis which lies in the image plane. Actually the projection of the image plane at 30° tilt is smaller than the image plane at zero tilt.

168
EOS-M / Re: FD lenses
« on: February 08, 2014, 09:17:32 AM »
I was wondering if there are any affordable but 'outstanding', 'good' or simply 'fun' FD(n) or FL lenses that you would recommend to use on a mirrorless camera like the EOS-M or Sony NEX that I own.

I have an FD adapter and tried the FDn 70-210mm f/4 on my NEX but the lens's performance was poor with lots of purple fringing. I sold it and now bought a Canon FD 200mm f/4 S.S.C.  that I have better hopes for.

Other old stuff I own:

Vivitar C/FD 28mm f/2.8 Auto Wide Angle
FDn 28mm f/2.8
FL50mm f/1.8 II
FDn 50mm f/1.8
FL 135mm f/2.5 (haven't tried this yet but should be fun)

What's your experience with adapted FD lenses?

I have checked with the EOS M
 4.0 17mm New FD
 2.8 28mm S.C.
 1.4 50mm S.S.C.
 3.5 50mm S.S.C.Macro
 1.8 85mm S.S.C.
 2.5 135mm S.C.
 4.0 200mm S.S.C.
 4.0 300mm New FD

and found that only

   1.4 50mm S.S.C. and  3.5 50mm S.S.C.Macro
   see http://www.canonrumors.com/forum/index.php?topic=16907.msg324375#msg324375
          the strip chaped crop is a 1:1 crop.

are optically very good and interesting.

The tele lenses are a little soft and show strong longitudinal CA (wide) open.

The 4.0 17mm might be interesting vor video because it has very low distortion and
good brilliance. Sharpness is o.k. for 1080p.

A true gem is the 3.5 35mm macro lens with the FD bellows.
But I have no infinity focus mount for that lens - a speciality lens.

Sorry that I cannot provide a "visual" comparison but it was eminent
from the first photos that the new EF lenses are much better - except
the two 50mm lenses I mentioned.

Using them on an EOS M is a pain because only Av mode gives good
exposure simulation - but EOS M has an exposure lock (*) button. It
is usable. The quality of the images which EOS M delivers, is very good.
I am trying to build a loupe adapter around an achromatic lens I still
have - with that "electronic" viewfinder finding focus is much easier
- thanks to the great display of the EOS M. There should be a finger
hole in the adapter to operate the touch screen - but this might be
done with ease.

Best - Michael



169
PowerShot / Re: Canon PowerShot G1 X Successor Coming Shortly [CR2]
« on: February 03, 2014, 12:38:54 PM »
.
[...]

Any smaller and it gets into the EOS-M range. With the EOS-M you get a lot more versatility with interchangeable lenses (and APS-C sensor, of course).

Current dimensions:

G1 X: 4.6 X 3.2 X 2.6 (in)
EOS-M: 4.3 X 2.6 X 1.3 (in)

[...]


That's what came into my mind after checking if a G 1 X successor is of some potential value for me:
DEFINITELY NOT - the EOS M has roughly the same size but gives much more flexibility.
What's missing (for me) is a compact 40mm or 70mm lens with e.g. 1.5 inch length ...

170
EOS Bodies / Re: Patent: Canon 11-24mm f/4 Lens
« on: January 26, 2014, 09:26:50 AM »
Some notes of a goo gle translation of the document (in both, german & english) gave some additional data not mentioned in the original article:

Filters: According to the Patent the front lens diameter is 84 mm - with a bulbous front element and that lens diameter filter size will be some 150mm with a special holder. Lens size is comparable to 70-200 2.8 (shorter but thicker)!

Optical Correction: Distortion is designed to be roughly 0.5% (FL not mentioned) at the cost of higher chromatic aberration. The idea is to rely on software correction for chromatic aberration.

f/4.0: High camera sensor sensitivity allows slower f-stops. Canon seems to find the main advantage in "Hyper wide angle capabilty" going below 14mm. They have f/4 & 11mm compared to Nikon with 2.8 & 14mm - if that lens is on the market.

171
Software & Accessories / Re: Adobe Lightroom for iPad Coming Soon
« on: January 18, 2014, 07:34:05 AM »
What has this to do with Canon?

Truly nothing, but I will try to find a "link" between iPad and Canon ..

Lightroom for iPad is boring,

Really exciting would be an iPadX which allows to run Max OSX and Windows and all the SW which is available like Lightroom, DxO or Canons DPP or EOS Utility (very helpful).

I gave up to wait for an iPadX and bought a 2nd hand Fujitsu Stylistic for 300 bucks + an 256 GB SSD for 200 bucks with 6 hrs of battery life (12 hrs with an extended battery) - not as stylish as an iPad but works and has a built-in sd card reader + large and bright display (13").

By the way: I hate the strategy to have 5 or 7 software versions for different operating systems with different licensing schemes in a world where it is possible to run a Windows, OSX or some linux on a smartphone sized computer.

172
Third Party Manufacturers / Re: Sigma 50 f/1.4 Art Lens Should be Amazing
« on: January 15, 2014, 11:44:48 AM »
I have made a simple synopsis of the sequence of lenses/lens groups and their type (divergent/convergent).
+ means a convergent lens, - a divergent lens, lens sequences without blanks mean lens groups

                  +- -+ Doppelgauß type
                + +- -+ + Planar type
            + + - -+ -+ +  EF1.2 50
        + - +-+ + +- -+ +- + Sigma 1.4 50 Art
        - - + + + +- -+ - + + Zeiss OTUS 1.4 55
         + - + - + - + - + +   EF 2.8 24 as another retrofocus design with positive first element


Sigma and Zeiss are similar in their complexity and roughly in the number of lens elements. I expect that the Sigma is much more comparable to the Zeiss OTUS in terms of IQ. But the Zeiss might have an advantage because it uses 6(?) lenses made from different special glass types while the Sigma has only 4 LD glass lenses perhaps of the same glass type. But this might result in a marginally better IQ compared to the Sigma.

But ... truly let's see real images to discuss the IQ!

173
EOS Bodies / Re: Patent: Microadjustment Automated
« on: January 12, 2014, 06:48:42 PM »
Let me be the difference adjusted value of the phase difference AF and contrast AF
To determine the reliability

Great...except that we know contrast detect AF isn't necessarily the gold standard for precision.  Given the specified and observed precision of both phase and contrast AF, I really think multiple tests are required for an accurate result.  It they implement this method, and it does just one contrast detect AF, I certainly won't be using it!

One part of the patent seems to be the reliability check of a contrast AF measurement:
"Canon patent to determine the reliability , seems to validate whether can be adjusted correctly . [...]  The play of the phase difference AF if that is the cause , because there should be aging , It is what you want also a mechanism to be calibrated on a regular basis ." (via google translate)

 There might be an algorithm which excludes a blue sky as welll suited CDAF object.

Additionally I would expect a calibration of all AF points - if they differ to much this might invoke some cross checks or a new measurement procedure.

174
The Zeiss Otus is nearly 10 inches long, which seems to be what you need to avoid the double gauss design. The new Sigma is an inch longer than the last one, at 4 inches so I highly doubt that it will be any other design, but we don't know for sure.

The Otus is about 6" long, I don't know if I call that "nearly 10 inches".
Sigma seems to have an "enhanced" double gauss design, by the way:

http://www.sigmaphoto.com/sites/default/files/311-lens-construction.jpg

I'm in no way a specialist and I might be wrong, but the 50mm Art design makes me more think it could be a retrofocus design like the Otus 55mm. Maybe someone with better knowledge could confirm or negate this.

I am shure that the new Sigma is a retrofocus design similar to the OTUS and just a little bit of an enhanced double gauss. I tried to list the lens sequency of different lenses/types: + means a convergent lens, - a divergent lens, lens sequences without blanks mean lens groups:

                  +- -+ Doppelgauß type
                + +- -+ + Planar type
            + + - -+ -+ +  EF1.2 50
        + - +-+ + +- -+ +- + Sigma 1.4 50 Art
        - - + + + +- -+ - + + Zeiss OTUS 1.4 55
         + - + - + - + - + +   EF 2.8 24 as another retrofocus design with positive first element


I marked the achromatic doublets red where I think the "Doppelgauß" genes might reside in the newer designs. From that I see that the new Sigma and the OTUS have similar genes and share negative elements in front of the core Doppelgauß which indicates a retrofocus construction.

Just my 2ct.

175
Lenses / Re: The 10 Oldest Canon Lenses in Production
« on: January 10, 2014, 01:24:34 AM »
The 100 f2 is underrated? The last one I tested had so much CA in it I could barely make out the image....ok that's slightly exaggerated but it was a LOT!

The lateral CA is near zero I the longitudinal CA is well visible at f/2 if you have strong contrasts like branches of a free against a bright sky. From f/4 on it's much (!) crisper than e.g. the f/4 70-200 L lens!
 But perhaps I had luck with my sample!

176
Lenses / Re: Question about Canon Lens Quality, Sir
« on: January 09, 2014, 09:08:17 AM »
I am too impressed with the quality of that "kit lens". I see two reasons why it has very good percepted sharpness:
(1) For a mirrorless system you can place the last lens where you need it. Most SLR wide angle (zoom) lenses are strong retrofocus constructions to keep the mirror area clear. Having more freedom in lens element placement gives you more options for a good overall correction of aberrations.
(2) A lot of aberration correction is done in camera or used as a preset for e.g. DPP. Perhaps this lens was developed with post processing in mind to correct aberrations.

Just my 2ct. Best - Michael

177
Interesting lens - which has overall a similar construction like the Zeiss OTUS - Retrofocus like basic construction, an aspheric last element and the use of 4 SLD lenses in a 50mm (Zeiss has 6 lenses of different glass types with anomalous partial dispersion).

I expect a pricing near 1000 $/EUR, a lens sharpness which is close to the OTUS and the main difference between them will be the general rendering of images.

Very interesting lens!

178
EOS Bodies - For Stills / Re: Aftermarket upgrading of cameras?
« on: January 04, 2014, 09:16:12 AM »
I suppose it maks sense that everything is soldered onto the board, to deter "improvements" by people.  [...]

That's not the (primary) reason to solder things on a board. The primary reason is that only soldering chips on highly optimized boards allows for the large bandwidths needed for fast signal processing. To read out 10 million pixels 6.5 times a second means very high data throughput for ANALOG signals from the sensor to the analog to digital converters.

Not really.  You can easily handle high-speed data with socketed chips.  Just look at the CPUs in a modern desktop computer.  And the data rate inside a DSLR isn't really all that high.  At 14 bits per pixel, using the numbers, you're only talking about 910 megabits per second—less than twice the maximum data rate for USB 2.0—and that's if you read the entire sensor's output serially through a single data line (which AFAIK none of the high-MP sensors do).  If you break the data up across several parallel data channels... well, it isn't a trivial amount of data, but it pales compared with the video RAM used in a modern GPU—at least three orders of magnitude slower, IIRC.

No, the primary reason for soldering everything is reliability.  Socketed chips have a tendency to work themselves loose, and thus would be problematic in something as mobile as a DSLR.  As far as electronics reliability goes, a good goal is to eliminate as many connectors as possible, and to move as much as possible to a single-board design.  Every socketed chip is just waiting for a chance to work itself loose and cause a device to stop working.  Therefore, sockets and other connectors are worth avoiding unless there's a really compelling reason to use them (e.g. using connectors for flash storage so that you can move the content itself from device to device).

For computers you are right, but I spoke about ANALOG signals with high bandwidth and precision.

179
EOS Bodies / Re: Canon abandoned EOS M?
« on: January 04, 2014, 09:08:57 AM »
Considering the enormous price drop, the non-release of EF-M 11-22 in the USA, and EF-M 22mm discontinued in BH site, it seems to me that the EOS-M system will be abandoned soon. What do you think?

I heard some information that Canon is switching more and more to robotic assembly of cameras - perhaps they proceed with that process to be much more flexible in the future.

Perhaps Canon company tries to implement production technologies to be flexible in terms of camera variations and scale of production before it tries the next "adventure" with a new model? The original EOS M suffered from the combination of a high price and not enough "features" for it's price. So it might be a good idea to add an EVF with "tiny" effort just by reprogramming the production line ...

For me, I like the existing EOS M with the standard zoom and it has replaced my S95. It is not as pocketable, but IQ is much better and it allows me to use my trusted FD 1.4 50mm S.S.C. lens.

EDIT: So I am shure that Canon will develop the EOS M line furthermore but I do not expect an EF-M 2.8 300mm - I see room for compact EF-M lenses between 10 and 150mm which harmonize with the small footprint of the EOS M. E.g. a compact EF-M 2.8 10mm with very good IQ would be a dream!

180
[...]

I'm hoping Canon just makes a third mount type that takes both EF lenses and allows lenses that sink 10-20mm into the body. You could have a 20mm pancake that only sticks out of the body far enough to have a switch and a focus ring.

Excellent point ... and would be consistent with a "minimized equipment for maximized purpuses concept". The larger flange distance of the original EF mount would help for a better grip, a larger battery and a ring dialer (like Powershot S95 ...-models). It wouldn't be as compact as a EOS M with the 2.0 22mm but has it's advantages for really good wide angles (and standard lenses).
And if they use an "EF mount" with smaller flange distance and a 10mm extension tube as standard part ... we would be open to use the whole world of FF lenses via adaptors.

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