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Messages - heptagon

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1
Magiclangern provides a button to "expose to the right". Adjust exposure in postprocessing to fit your needs. Problem solved, case closed.

And how, exactly, do you do that? Because if you are using the 'Blacks', 'Shadows', 'Exposure', 'Highlights', or 'Whites' sliders you are not getting the tonality of the scene.

If you use tone curves on each colour channel seperately, if you are using the camera calibration panel etc then yu might be getting close.

You seem to be missing the point that 'simple' adjustments to an overexposed file do not get you back to the same tonality as a 'correctly' exposed file.

The RAW data is linear. If you expose to the right, you just collect more photons. In software you have to reduce (or increase) the exposure by the same amount that you adjusted while taking the picture. Then you have the same raw data without blown highlights (when decreasing exposure taking the picture) or with less noise (when increasing exposure when taking the picture).

You do not need to change the channels separately. You do not need to change the tonality curve.

The required correction is only one single value. E. g. +2EV while taking the picture and then -2EV to reverse that effect in software.

That is the theory and software which does that is fine but there are many things that can go wrong. One big difference is the tonality curve of the camera (software) which is applied to convert linear RAW data to JPEG values. You cannot work with those JPEGs, you need linear RAW. But even then the RAW is preprocessed by software and that might do some things like change the color of dark/bright parts. E.g. reduce the color of dark parts to avoid color noise.

You can simply test your software. Switch to manual mode and take a photo of some dark objects before a dominant white wall and expose like the camera would do (make the white wall grey). Then expose to the right and remember how many EV you increased the exposure. E.g. 1/100s camera exposure vs 1/25s ETTR exposure = +2EV. Then use the RAW files and convert them with your software and apply -2EV exposure to the second picture. Now they should have EXACTLY the same color properties but the ETTR picture should have less noise. If not, your software is not up to that specific task.

Using the camera JPEGs here will lead to totally wrong colors, banding etc. due to all the "optimizations" applied to the RAW data in order to get good looking JPEGs.


At the end of the day the goal is to take a picture and to expose for that specific subject and the sensor noise may actually be low enough that you are satisfied with the exposure suggested by the spot metering of the camera. In that case you can directly use the camera JPEGs and be fine. Heavy postprocessing is only for low volume activities or people with too much time.

2
Magiclangern provides a button to "expose to the right". Adjust exposure in postprocessing to fit your needs. Problem solved, case closed.

3
What do common people want what only a large DSLR can give them but a smartphone can not?

AF/resolution/color/dynamic range isn't that much of an issue for smartphone cameras. I think it's mostly low light sensitivity and blur/Bokeh.

Most photos are made throughout a sunny day and many times blur isn't even desired. Why would we want to sell them big chunky DSLRs?

Not because they need them but because they want them inspite not needing them. That makes for an unstable market. People buy a DSLR, realize it's not for them and that's it. A tiny percentage may be converted and buy the more expensive stuff. This time mostly because the can afford it and make better photos than with their smartphone but the majority of these people do not need these photos and therefore do not need new equipment if money becomes tight. Even some journalists start switching to smartphones because it's good enough for the photos they need to take. That's the point. Non-DSLR-solutions are good enough for most people but have many different advantages like size/price/flexibility.

4
EOS Bodies / Re: Canon Confirms Development of High Megapixel Camera
« on: December 31, 2014, 11:22:30 AM »
It was some rumors about Canon wanting to move 6D upmarket, if that is the case, then it does make sense to give the 5D4 52mpx, if the 6D then becomes the "real" 5D4, under the cover of the name 6D2. Hopefully it stays below 36 mpx as well.

This actually makes a lot of sense. Providing the 5D4 with the 6D sensor and keeping the rest of the 5D3 wouldn't sound as good an upgrade than providing the 6D2 with the 5D3 focusing system. - The result is the same but now the 5D4 leaves an open space where a new high-resolution sensor could find place.

Or they may as well call it the 2D, 3D, 4D, 8D, 1DXs, 5Ds... whatever.

5
EOS Bodies / Re: Canon Confirms Development of High Megapixel Camera
« on: December 31, 2014, 11:16:55 AM »
Looks like I'm the only one who's looking forward to a high MP 5DM4.  Add in GPS and the 7DM2's focus and I'm sold.  Canon needs to respond to the competition. So many Canon users have defected to Sony and Fujitsu because Canon is no longer meeting their needs.

People complain loudkly in forums and yet Canon sales remain good.

They are not. According to Canon financial statements their DSLR sales have been into a double digit fall in both 12/13 and 13/14... So I'd say - and I'm pretty sure the board room talk is - "Canon DSLR sales are dismal and we need to act now before its too late".

Sales are falling across the board. The most reasonable way to improve figures is to cut research and up on marketing. Those who buy cameras don't even know what we are reasoning about here in the forums.

6
Reviews / Re: Bryan Carnathan has completed his review of the 7D Mark II
« on: November 24, 2014, 03:32:47 AM »
Looking at the noise comparison above ISO3200, the 7DII clearly is a little bit better than the 70D. - I suppose this is about as good as we get with Bayer pattern silicon sensors. It is not possible to make large gains.

Reduce read noise? At high ISO, the Canon sensors are already close to the limit.
Improve Quantum efficiency of the subpixel? Yes, but not with current silicon.
Use multicolor subpixels? This hasn't worked out well, so far, with silicon.

In that light, even the tiny gains, that Canon could achieve, are great.

Current sensors throw away a lot of light. Color filters block out a lot of light from the other colors. Green is the most important channel but only half the pixels detect green. That would be almost one stop improvement if every pixel was green.

I would expect 1-2 stops improvement when the sensor manufacturers move on to utilize new materials to build Layered sensors with multiple colors (possibly more than RGB) and 90% quantum efficiency throughout the spectral range.

7
Lenses / Re: Preorder: Canon EF 100-400mm f/4.5-5.6L IS II
« on: November 13, 2014, 12:14:40 PM »
Well, it seems to be a really really nice lens. But I won't preorder. I will wait for the first batch to get out so that the quality control fixes the early bugs. Then I'll wait some more because the price might come down a little bit. Then I'll wait even longer because I don't _really_ need this lens. Then I'd consider which camera to use with this lens. It should presumably be a crop camera. That camera would be the 7DII. Buying one without the other is pretty pointless in my case. This bumps up the price considerably. So I'll wait even more until the "fun" account bursts with money unless it gets drained by some other toy. But then, finally, I'll buy it and it will be nice.

8
Lenses / Re: First Image of the EF 100-400 f/4.5-5.6L IS II Lens
« on: November 07, 2014, 05:44:50 PM »
I'd be interested to see a comparison when these are out.

100-400L II at 400mm and f/5.6 upresed 50% compared to Tamron 150-600 at 600mm and f/6.3.
100-400L II + 1.4x TC III at 560mm and f/8 compared to Tamron 150-600 at 600mm and f/8.

My prediction as that both would be a near tie, except the Canon will have less CA and faster focusing on the first test.

my prediction is that the first comparison would put the tamron far ahead for total detail, 200mm is an insane amount to make up for, the tamron would have to pale even compared to a coke bottle for that to be true

now in the second case maybe it would be about a tie???? who knows or even better?

Results are mixed, see for yourself:
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=113&Camera=453&Sample=0&FLI=10&API=2&LensComp=929&CameraComp=453&SampleComp=0&FLIComp=5&APIComp=2

The Tamron loses a lot of quality from 500mm to 600mm.

9
EOS Bodies / Re: Canon 7Dii vs Nikon D750 Dynamic Range Test
« on: November 02, 2014, 12:48:30 PM »
Thanks for your post. A comparison with the 70D would be nice everything points towards that they have the same sensor.

10
Lenses / Re: Why does a 2x TC lose 2 stops?
« on: October 29, 2014, 10:49:11 AM »
The reverse is also true: A 0.5x TC gains 2 stops.

Those are usually sold as speed boosters to use a full frame lens on a crop camera. If i recall correctly, some lens designs with a wide angle and a large aperture have such an element built in.

11
Lenses / Re: Review: PowerShot G7 X via DXOMark
« on: October 27, 2014, 02:59:15 AM »
Canon, do you hear us? We want a 50MP high DR Sony sensor in a 6DII body for 2500$. It doesn't need many focus points, it doesn't need the best low light performance, it doesn't need to be fast. We want many good pixels at ISO64 and an EF mount.

12
Joining the bandwagon: 6D first.

a) buy it with the 24-105 kit, to get a cheap and useful zoom, b) buy the tamron 24-70 f/2.8 VC to get a good versatile zoom for a reasonable price, or c) buy the canon 24-70 f/2.8 II if you want to go expensive.

The 7DII isn't even out yet and the focusing system ist the only big advantage.

13
Lenses / Re: Thoughts on Having a 35 and a 50 on Crop?
« on: October 11, 2014, 10:31:33 AM »
You're just shooting 50 and 85mm. Think of the conversion, not what says on the lens.

This is not true. You still need to consider actual focal length. Just because there's a crop factor it does not change the actual focal length of the lens. There's a big difference in distortion between 35mm on a crop and 50mm on full frame. The field of view will be similar but the 35mm is still a 35mm, regardless of the size of the sensor behind it.

These two configurations produce _exactly_ the same image (same distance to subject, same shutter speed):
Full frame: 56mm, f/3.2, ISO250
Crop: 35mm, f/2.0, ISO100

The advantage of full frame is you have lower ISO available, faster f-stops available and more field of view available.

The advantage of crop is you use the center part of the image, so you get better bokeh but less blur for a frame filling subject. You also get a longer reach and better edge sharpness. Additionally when using crop lenses, you have lower cost and weight.

Using a big sensor camera has only advantages once you get faster than about f/1.4-f/2 on the current model because faster lenses cannot be made easily. Instead it is easier to increase the sensor size and image circle and use a sharp f/2.8 lens on a medium format camera instead.

14
Canon General / Re: seeimpossible.usa.canon.com?
« on: October 07, 2014, 12:10:20 PM »
So, if I read this correctly, Canon have given up trying to compete with other manufacturers technology, and instead are going to focus on stories about how their customers "use" the products they make as a sales pitch?

Great. So we can expect smoke and mirrors but no substance.

It is like a fashion house deciding to focus not on being the cutting edge of fashion, but rather on how their customers were their garments in everyday use.

Where does Canon say that exactly? :o

You have to read what they don't say.

In the last years Canon never said they'd give us better low ISO performance (or that anyone buying their cameras cared).

Canon seems to be able to sell inferior technology at a premium price. I wouldn't be surprised if they start selling rebranded Nikon cameras with a EF mount and a firmware that provides Canon ergonomics.

15
After 25 pages this thread is starting to provide some useful information. How disappointing. :)

Can we go back to lifting shadows by five stops and arguing over banding?

With the 6D, the banding issues are basically gone. 5DIII shooters just use the wrong tool for the job and should get add a 6D to their kit.  ;)

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