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Messages - mb66energy

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31
Third Party Manufacturers / Re: Sigma 50mm f/1.4 Art Gets Reviewed
« on: April 06, 2014, 06:28:10 AM »

One more thing learned -- weighs 28 oz /  1.75 lb / 0.8 kg.

- A

Wow, that's quite heavy for a 50/1.4!

:) I thought it was 470g (from dpreview).

I think a factor of 3 to a double gaussian optics is a good rule of thumb for a weight conversion into a retrofocus lens like the new sigma, 300 grams (for EF 1.4 50) x 2.5 is 900 grams. The sigma seems to use metal compared to the EF 1.4 50.

2 times the length + 1.2 times the diameter means 2 x 1.2 x 1.2 ~ 3

32
Canon General / Re: No one sees it like you....
« on: March 31, 2014, 08:22:04 AM »
Has to be some type of composting -- optical or software.  I don't see anyway to have decent focus on the eye itself and the reflection at the same time if it was a straight shot.  Focus distance to the eye is very short -- maybe an couple inches max.  the reflected image focus distance is the actual distance to the object reflected -- several feet to infinity.  (Try this test, take camera and focus on your own reflection in a mirror, then without changing focus, shift sideways so the frame of the mirror is in view.  It will be out of focus.  Refocus on the mirror edge and your reflection goes out of focus.)

A flat mirror is the wrong comparison.

You really don't need CGI to have sharp eyes AND sharp reflections see the image below which is a simple proof. The image is made with an APS-C camera, HD video mode, f7.1 @60mm (EF-S Macro). @f/2.8 the same situation.
The cornea is a spherical mirror (in that case) and acts as a second optical element providing more or less sharp images.

The only problems are:
  - avoid the reflection of the imaging system
  - getting enough contrast (as you can see with my image with blue-gray eyes) - dark (e.g. brown) eyes are
    much better but i have to live with what I have.

CGI is much cheaper and using a fisheye will give satisfactory distortions which are well accepted as reflections form the cornea.

So everyone is right - at least a little bit ...

EDIT: Forgotten the attachment  - now available ...

33
PowerShot / Re: Canon PowerShot G17 Coming in May? [CR1]
« on: March 30, 2014, 02:09:23 PM »
This might be an EOS M killer ... at least for a lot of potential users.

The factor of 2.8 makes the lens a 8.5 - 72 mm lens. f/2 @ 72mm means 36mm aperture. This seems possible.

Hopefully the IQ is at least very good over the wide range at wide apertures.

34
EOS-M / Re: EOS M Lens survey - your favorites, and your most wanted?
« on: March 26, 2014, 12:32:18 PM »
I have only the 18-55 EF-M as a system lens and it replaced (incl. the EOS M) my S95 which was not good enough in terms of IQ.

EF-M 18-55: very good quality for a zoom
EF converter + EF 40 STM: Better IQ, nearly the same size but much less flexibility
EF converter + EF-S 60 USM: Better IQ, a little bit on the larger side
FD 1.4 50mm S.S.C.: Very good IQ from f/2, but clumsy to work with for AF (EVF would help massively for manual focus without fiddeling around with magnification etc.)

=> A 2.0 or 2.8 50mm with IS, STM compact outline and close focus capability (1:4 magnification o.k. for me) would be a great addition / lens I wish ... better f/2.8 and stellar IQ than f/2.0 and very good IQ

35
Third Party Manufacturers / Re: Samsung NX mini – I'm speechless
« on: March 21, 2014, 05:51:16 AM »
[...]

Quote
The camera features a solid premium metal body with a luxurious leatherette finish, making the camera the natural choice for style-conscious shooters looking to make a statement.


Is this really where photography is headed?

http://photorumors.com/2014/03/18/samsung-nx-mini-smart-camera-announced/#more-56044


I had the same feeling while walking around a lake/forest to photograph:
Person: "What is the brand and name of that camera, you use?"
Me: " It's the EOS M from Canon."
Person: "It is a nice looking camera ..."
Me: "And it has a very good photographic quality like the SLRs with similar sensors."
Person: "The finish is very nice, great surfaces and good design." His eyes were absorbed by the camera.
Me: "But more important: You have a great photographic tool in a tiny package ..."
The person's mimics lead to my conclusion that he has a totally different idea of what cameras are built for ...

36
EOS Bodies / Re: Hardware Hack for EOS Cameras Coming Soon? [CR1]
« on: February 28, 2014, 06:20:10 AM »

[...]

<p>As for the modification itself, it’s said it will “greatly improve dynamic range and video sharpness and performance in the EOS 5D Mark III.”</p>

[...]

Optimized PCB layout might help to get the pedestal noise down which increases DR directly. Perhaps they introduce some intelligent readout which reads the sensor twice to extend the DR by increasing the max counted photons per subpixel. Sometimes tiny alterations of PCB layout reduce "electronic dirt" on signals making them cleaner, more realistic.

Our brain disciminates very subtle changes in signals. Think about sound reproduction: I added a dipole subwoofer to my very good loud speakers and the rendering of sound below 35Hz is magic - I don't hear to much new things in that region.
Listening is much easier than before; from psychoaccoustics we know that the brain adds missing details very effectively like bass sound from higher frequencies. But I think, the brain has to do the calculation of missing details - if you add the detail you need less processing power which can be used to enjoy the music.
The same might apply to optics/cameras.

Another thought: cooling or at least stablizing the temperature to something like 20 degree celsius for sensor and ADC might help to reduce noise sources substantially.

IMHO substantially higher frame rates are not possible because the shutter mechanism will limit fps for an EOS 5D MarkIII.

37
EOS Bodies - For Video / Re: Laser Light Burns a DSLR Sensor in Canon 7D
« on: February 23, 2014, 08:21:11 AM »
Yup, we see posts about this from time to time, its been happening for years, but a reminder every once in a while might prevent someone from having the issue.

A useful reminder to have, thanks.

Does anyone know what about the laser actually kills the sensor?

The energy transported with the LASER light is converted into heat if the light is absorbed by the chip. The heat might damage the structures on the chip consisting of the pixel structure and conducting signal lines.

The problem with movie mode and live view is that the chip is alltimes exposed to the light. If the image of a light source is intense enough you might heat up the chip structures to temperatures above spec. This might be around 100 degree Celsius.

LASERs are monochromatic and the light bundle is nearly parallel. The light is focused to one tiny spot - 1/1000 mm is possible - with a single lens, more with a well corrected lens. If the thermal energy cannot be removed by thermal conduction in the chip to the back or outer regions you have some pile up of thermal energy which means increased temperatures. The tiny structures made of different materials/material combinations mix by diffusion of atoms due to the heat.
With blue light there might be another effect: Blue light consists of photons with higher energy per photon and these photons can damage structures directly - think about ultraviolett radiation which has again more energy per photon (=light quantum) and might damage biomolecules resulting in cancer generation!

If I have the sun in the frame I try to use the diaphragm control button to reduce the heat load on the sensor - this is one possible measure to reduce heat/high temperatures on sensor regions.

38
Lenses / Re: Another Mention of a New Macro Lens in 2014 [CR1]
« on: February 14, 2014, 12:58:51 AM »
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.

All the macro lenses you just listed do not use internal focusing, so your point is moot. I did not argue against macro lenses in general, only against macro lenses with internal focusing.

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!

These lenses do all kinds of crazy stuff, but when it comes to focusing they are still as they always were: internally focusing lenses which forfeit focal length at MFD for elegance, and lenses that maintain their focal length but become longer as you focus closely.

I own the 60mm and the 100 mm USM Macro-both do NOT extend and use (including the 180mm Macro) after Canon's USA home page a
 "Focus Adjustment:    Inner focusing system with USM"
 - so I do not understand your arguments - or is there a difference between "inner focusing system"  and "internal focusing"?

39
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!

40
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.

41
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



42
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 ...

43
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.

44
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.

45
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!

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