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Messages - mb66energy

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166
I checked, it says 1920x1080 resolution. :)

Just seen your correction - 2560 x 1440.

There SHOULD BE no difference between e.g. 10 or a 36 MPix camera if both give per pixel sharpness and are downscaled by a good algorithm including some sharpening after downscaling.

What about the idea to prepare 2 photosets with different cameras of a similar (same) object/scene, scale them down to 1920 2560 Pixel width and do the comparison?

167
So a higher MP camera, case in point D800, will not show any better IQ due to resolution on my 27" Imac?

What ist the resolution of your 27" Imac?

168
REQUEST:
Can anyone guide me to a study which indicates that high MP results in poorer IQ? PLS.
[...]

I cannot guide you to such a study and I am shure you will never find such a study because:

If the per pixel quality stays the same, more pixels give always better IQ until other factors like lens IQ are limiting.

Lower pixel counts help to reduce processing time and filesize which may be valuable for some purposes but nothing less/more. 

I am physicist and it was never bad to measure values as precise as possible - it was bad to measure with less than required precision! If you don't need the precision you can report rounded measurement values - if a light bulb has a power consumption of 60.22412 Watts or 60 Watts essentially is not important for a bulb user, but perhaps for a lamp design researcher who optimizes the production process.

Hmmmm. Then why the resentment to better IQ? That is what I am trying to understand.


I think may people are saying they would like the improvement in 'IQ' with files that are not as large, because they already have more than enough resolution for a highly portable 35mm type camera.

+ I feel that the reality of much higher MP on FF chip ( or APS for that matter) only manifests itself in 'higher IQ' when the photographer is viewing his images at 50 - 100% on his computer screen. Although this may give the photographer immense satisfaction it is not actually producing a better picture for display to anyone else.

I forgotten to refer to TECHNICAL IQ in my lines.

Sporgon, your argument (underlined) is IMO correct. I myself are satisfied with my 40D in terms of technical IQ .... FOR WHAT I DO: Photographing things and landscapes because I like to do it and viewing the best pictures for pleasure as 30x40cm (12x16 inch) prints or via a XGA-Beamer (1024 x 768 Pixels, 0,8 MPix (!!!)). A photograph with valuable content and expression works always on 12x16 inch or e.g. a 2 MPix beamer.

Furthermore I see no dramatical technical IQ gain with the 18MPix sensor of the 600D.

But I would take a 48 MP full frame sensor for one reason: Coulors of e.g. monochromatic light sources would be much cleaner if you downscale it to 12 MPix to have 1 red, 2 green and 1 blue subpixel for one final image pixel. Bayer demosaicing gives strong artefacts for e.g. LED tail lights and red sunsets. Therefore I miss a sRAW mode in my 600D which gives me 10 MPix or so.

sanj: "Then why the resentment to better IQ?"
Alternatively I could say "24 MPix for APS-C is bullshit, 10 MPix is enough". BECAUSE I have only 10 MPix at hand and no money to buy a better resolving camera. I think is more or less a psychologial resentment.

169
Lenses / Re: Teleconverter
« on: March 27, 2013, 04:48:42 AM »
every extra bit of glass will reduce iq

O.k. so I will put my eye glasses down ... asüdü aüfbis fiasbfsl lxc ... no, with eye glasses IQ is better and I see what I am typing!

170
Lenses / Re: Teleconverter
« on: March 27, 2013, 04:45:53 AM »
I'm considering getting a 2.0 teleconverter for my 70-200 2.8. Other than going to 5.6 does it also reduce the iq?   Thanks I'm still learning here.

1 A TC reduces the IQ systematically because it blows up the image of the naked lens by a factor of 2 (for a 2x converter you are considering) - lens flaws are scaled too. The upscaling by a factor of 2 means that the same light is distributed to a 4 times larger area reducing in 2 stops light reduction.

2 A TC introduces additional glas elements and reflects/scatters light. Modern zooms have 10-20 lens groups, the 4-6 lens groups of a TC will have some effect in this department, but it will be moderate.

3 Some TCs are co-optimized with one ore a few lenses. I am shure that Canon optimizes them for the 2.8 300 and the 2.8 400 lenses and that different TC series are optimized for the corresponding lens series. If you have an old 2.8 300 the 2x TC of the first series MIGHT match better.

I have the 2x TC version I (170 bucks 2nd hand) and it works well with my 4.0/70-200 L 4.0 non-IS and the 5.6/400. I decided to get the 5.6/400 because it's IQ is very fine from f/5.6 and I have a longer reach with TC.

Best you can do: Try your telezoom with a 2x TC (optimum: I + II + III series) and check the results for YOUR PHOTOGRAPHIC APPLICATION)

ADD (just seen): Kerry B's remarks about the 300 support my 3rd point!

171
REQUEST:
Can anyone guide me to a study which indicates that high MP results in poorer IQ? PLS.
[...]

I cannot guide you to such a study and I am shure you will never find such a study because:

If the per pixel quality stays the same, more pixels give always better IQ until other factors like lens IQ are limiting.

Lower pixel counts help to reduce processing time and filesize which may be valuable for some purposes but nothing less/more. 

I am physicist and it was never bad to measure values as precise as possible - it was bad to measure with less than required precision! If you don't need the precision you can report rounded measurement values - if a light bulb has a power consumption of 60.22412 Watts or 60 Watts essentially is not important for a bulb user, but perhaps for a lamp design researcher who optimizes the production process.

172
[...]

Seems that the most desirable quality of the D800 would be the impressive dynamic range it offers.

I'd just like to ask, you folks think cameras will ever reach the DR our eyes and brains could resolve and if so, the impact it could have on photography?

[...]

In my opinion:

AD 1 (DR of D800): I think DR will allways help to capture reality as close as possible.

AD 2: Very good question because you included the brain: I think a real 20bit DR sensor with a 20bit DR display will convince our eye and brain to see the real thing.
Physically a 20bit DR sensor is easy to built, but technically it is not. Think about an ISO 6 sensitivity and the capacity to collect large amounts of charge per pixel without saturation ... you will be fine: Pedestal noise is the same but saturation is far away and increases the DR. Physically.
Technically: I think you have to go into the 3rd dimension for sensor pixels charge storage and a good 20bit ADC is available but slow (at the time). 3D-Sensor design is IMO the real challenge because you have to create millions of 3D structures with small tolerances between them in the size of some microns. A 12 Mpix full frame sensor with a DR of 20bit would be sufficient (for the beginning) and blow away a lot of other sensors for some photographic fields.

I am shure that a lot of companies do research to built such (sensor) chips. A lot of chip technology has 3Dish structures just now. Hopefully we will see good sensors soon in Canon cameras - I don't have money/time to reinvest in new glass ... and hopefully we will see large OLED displays which provide DRs of 14 or 16 bit easily.

173
Lenses / Re: Best tele prime for full frame?
« on: March 25, 2013, 05:48:31 PM »
You should most definitely give consideration to the 100 f/2. I own it and highly recommend it. Light and fast, very inconspicuous, handles great, very nice IQ.

I think it's one of the most under-appreciated lenses that Canon makes. Just about the ideal match for your application. It will take up a lot less room in your bag than any of the alternatives you mention, also. See if you can borrow or rent one to try out. Oh, and they are relatively cheap, too.  :)

+1 to every point, TW has written.

It is a good companion to my 24/2.8 and 40/2.8 in terms of size, weight, IQ and unobtrusiveness!

174
Ok, here is another go.  This time taking into account some recommendations from the crew here:

105mm
F5.6
200 Shutter
100 ISO
Tripod

[...]


Do you have some noise reduction settings activated? Just minor setting of noise reduction (I use DPP) washes out irregular finely detailed structures - this cannot be deactivated (in my 40D) inside the customer function menu so I have to tune that setting to zero after downloading the images. Just an idea ...

Best - Michael

175
EOS Bodies - For Stills / Re: 5Dc a good option?
« on: March 24, 2013, 02:08:02 PM »
I just had the same thought yesterday checking different dxomark results for different camera-lens-combos. My observation: the 18MPix sensor of a 7D gives you just a few megapixels more USEABLE resolution than a 40D. This supports my (unscientific but well founded) observation that the sharpness perception of my 40D doesn't quite differ from that with my 600D with good lenses: 24mm f/2.8, 40mm f/2.8, 100mm f/2.0 etc.

dxomark results support the same for FF cameras: With a 5Dii you will not gain twice the resolution of a 5Dclassic but perhaps 10 or 20 percent ... except with a 70-200 f/2.8 ii ...

A 5D classic would be interesting just for me at 600 Euro from a dealer (1 year warranty) and be compatible with my stock of BP-511 batteries. 12 Mpixel Raw files would be very handy and sufficient for my purposes.

On the other hand: No video, a moderate LCD are drawbacks to me. And video support might be of interest for me. And there is the sRAW mode to decrease the stored MPixel count to keep files smaller (never tested it but it should be the case).

Wanted to share my thoughts because I am in the same decision process. But there is a good chance that I will wait one or two years ... APS-C is so good compared to what I see from the film slides I reproduced the last days ...


Best - Michael

176
Technical Support / Re: "Ripple" in Image with ND Filter
« on: March 24, 2013, 12:18:08 PM »
This is a disturbing finding.

From your second photo I see the pattern on the filter itself which might be generated
by
  * a thin layer of fluid on the filter OR
  * an air gap between different layers of the filter.

EDIT: Read your text twice again ( I am no native speaker/reader ) ... The pattern on the filter on your
2nd picture are newton rings caused by the cleansing fluid you used.

Which light source do you have used in the second image? Were it CFLs ("energy saver lamps")? They have longer coherence lengths and show the interference patterns of newton rings better compared to incandescent lamps.

About your first photo: Was it an image through the filter? Which lens do you have used?

Never seen such a thing before - e.g. with my B&W ND 1000 filter ...


Best - Michael

177
Lenses / Re: small primes to go with SL1?
« on: March 22, 2013, 10:45:02 AM »
I don't see wide angle primes in pan cake format for EF/EF-S mount because the flange distance doesn't allow very small lenses with high quality. You have to use a retrofocus design which needs negative lenses in front of positive groups and therefore consumes space. A very contrasty, sharp and distortion free lens like a f/4.0 25mm seems possible with perhaps 30mm length. But nothing more.

One existing pancake like lens is the Color Skopar of Voigtlander:
  * NO AF
  * Moderate IQ
but
  * small size
  * great mechanics
I never used it and I am not interested because I have the old 24mm f/2.8 from
Canon which is a little bit larger but gives me the IQ I need and is made from sturdy
but light plastics. Perhaps that lens is another alternative for the 100D (and should
be cheaply available).

SL II lens collection of voigtlander (except 58mm lens available for EF mount):
  http://www.voigtlaender.de/cms/voigtlaender/voigtlaender_cms.nsf/id/pa_fdih7pyj95.html

A test of the 20mm:
  http://www.photozone.de/canon_eos_ff/504-voigtlander20f35eosff

Best  - Michael

178
EOS Bodies / Re: EOS 70D, DIGIC 6 & 18mp Sensors
« on: March 21, 2013, 06:16:08 AM »
If the MP count has not changed then the underlying technology behind the pixels/sensor has not changed. i.e. there will be no DR/noise improvements over the 60D.

Indeed. I do not see why Canon does not want to take advantage of an improved sensor design to venture into higher pixel count territory. It is after all a chance for them to brag.

What if they can't?
What if some n years ago, they reached a point where they couldn't improve any further?

I am shure that canon is able to build revolutionary sensors intellectually and technically ... but they can't bring it to market because of intellectual property reasons (patents etc.).

Compare an EOS 20D (2004) and a some current model: There has been slight progress in IQ compared to the decade before the EOS 20D has been available.

Today's sensors are mostly out-developed and the headroom for improvement is small. Now Sony has found a profound improvement in DR, perhaps by the only available technology at the moment. They protect it by patents and other companies are blocked ... until the other companies find another way to improve sensor DR without offending existing patents.

179
EOS Bodies / Re: Canon EOS-b Images Leak & a New Kit Lens
« on: March 19, 2013, 02:13:09 PM »
Looks a lot more interesting to me than the under performing M series.

Just made this gif, the b is much smaller than the T4i.

A good comparison between both cameras that you provided here.

EOS b opens the opportunity to use 1 or two secondary cameras in
a standard photo backpack - by putting them with a lens attached
into a standard lens compartment. This might be the "intelligent rear
cap" for EF(-S) lenses and makes a really cute combo with the 2.8/40mm!

If I had not invested into a EOS 600D(T3i) it would be interesting ...  if
it has the video zoom mode (3x) with a 100% crop of the sensor center
region (5.6 400mm with 2x TC results in 3840mm focal length!).

180
Canon General / Re: Which eye do you shoot with?
« on: March 15, 2013, 02:13:05 AM »
Always right eye for view finder
Always left eye open to see what (or who) is going on

Only one severe problem with this procedure:
During a solar eclipse in 1999 I used a 600mm lens WITH FILTER to observe
the sun and its corona. After the total eclipse I have remarked the dangerous
situation for my LEFT eye (open as always) after several seconds and
had a black spot for several weeks (luckily it was off center of my personal
image field!).

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