Just pondering a change of digital cameras and have read through the long previous threads on here.
Seems in the superzoom compact and bridge camera market there is an issue with too many pixels on too small sensors causing noisy images at higher ISO (or at all ISOs).
So... if you were happy with every other aspect of a camera is it as simple as going into the menu to... say... select a 12mp setting rather than the max 16mp so the sensor/image issues aren't seen??
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The problem is because the sensor is too small and with too many pixels. Going into the menu will not overcome the limitations of the sensor.
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>> The problem is because the sensor is too small and with too many pixels. Going
>> into the menu will not overcome the limitations of the sensor.
It will if you limit the resolution to the abilities of the sensor. Too many cameras make stuff up.
Bridge cameras or superzooms are chosen because of the convenience. The best shot is the one where you have the camera to hand.
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>> The problem is because the sensor is too small and with too many pixels. Going
>> into the menu will not overcome the limitations of the sensor.
That is correct. The raw data from the sensor contain all the information there is, with any inaccuracies. You can't add quality back if it isn't there, so you won't improve the picture by reducing the number of pixels in the "developed" file.
The best way to work around it if you can is to use lower ISO, plenty of light helps, obviously.
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Or setting a max ISO, say 800, or even 400. lets be honest, in the old days, you had a fixed ISO to work with and you took what pictures you could with that. People only rack up to huge ISO number because they can. Its sheer ruddy laziness and lack of appreciation of the lighting issues.
Too few people these days have known what using film was like.
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>> Or setting a max ISO, say 800, or even 400. lets be honest, in the
>> old days, you had a fixed ISO to work with and you took what pictures
>> you could with that. People only rack up to huge ISO number because they can.
>> Its sheer ruddy laziness and lack of appreciation of the lighting issues.
>>
>>
>> Too few people these days have known what using film was like.
True, and and we won't be getting any more numerous!
If I were buying a camera today, it would be one of these
www.dpreview.com/reviews/panasonic-lumix-dmc-lx7/
I'm not, because I already have an LX3, 4 years and two versions back of the same camera.
The interesting thing and the point is, the effective pixel count at about 10MP is the same for both. Pixel count isn't everything, and is counterproductive with a small sensor (and these enthusiast cameras have bigger sensors than the more zoomy compacts, many with more MP).
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>> If I were buying a camera today, it would be one of these
>>
>> www.dpreview.com/reviews/panasonic-lumix-dmc-lx7/
>>
Good call. I have the DMC-FZ18 "bridge" camera and it's ruddy marvellous. Panasonic's image stabilisation is almost miraculous. Who'd have thunk that it was possible to use a lens zoomed out to 500-odd mm (35mm equivalent), handheld, on the deck of a racing yacht in the North Sea? Also its handling of heavily backlit subjects is astonishing.
Only two snags.
1) The flash is rather fierce, especially at close range. Ideally I'd like a hot shoe for my old Olympus T32 (still the best flash I've ever had my paws on). I've heard that the later models are better here and this is the only thing that might lead me to upgrade.
2) It's a heck of a sight better at getting a picture "right" in its "Intelligent Auto" mode than I am playing with the settings. This one irks me a great deal.....:-(
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My ultra critical view on digital cameras is because I want them to do it all I suppose.
Excellent 1080 HD video with a perfect image stabilisation is crucial to me... as is the ability during video to perfectly keep focus during and after zooming which some otherwise decent cameras don't do. Zoom needs to be absolute min 10x for video... 20x or more a plus. Still favour the shirt pocket size but trying to be flexible there so choice is increased.
Re pixels are they a physical thing that made onto the chip then when you reduce resolution in the camera menu you only use some of them?
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>> My ultra critical view on digital cameras is because I want them to do it
>> all I suppose.
>>
>> Excellent 1080 HD video with a perfect image stabilisation is crucial to me... as is
>> the ability during video to perfectly keep focus during and after zooming which some otherwise
>> decent cameras don't do. Zoom needs to be absolute min 10x for video... 20x or
>> more a plus. Still favour the shirt pocket size but trying to be flexible there
>> so choice is increased.
>>
>> Re pixels are they a physical thing that made onto the chip then when you
>> reduce resolution in the camera menu you only use some of them?
Essentially you have a sensor with a fixed number of cells.
Some cameras then "make up" cells in between based on the value of adjacent cells, this is interpolated. So ideally you want to use the native resolution of the ccd all the time
Not less or not more.
Resolution all depends on what you want to so with pics.
If its to display on anything electronic high resolutions are a waste of time unless you intend to do aggressive cropping. Same goes for print , you only need high resolutions if you will print large posters or print heavily cropped pictures. If you are going to crop that heavily someone needs to have a quiet word in your shell like about how to compose pictures
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The 'pixels' as far as the sensor is concerned are physical and are what capture/measure light. With colour filters (typically but not always a Bayer filter arrangement) you can capture the image.
If you scale down the resolution, the camera will downscale the image using the information from all of the sensors. Some will argue that fewer larger sensors capture more light, other will counter argue that combining the information from lots more smaller sensors (including interpolation) is a better solution.
All I know is that in poor light conditions, the faster the lens and image stabilisation makes more of a difference. My experience from various cameras:
- Sony a100 DSRL - APC-C sized sensor - very good in low light with optically stabilised sensor (not lens)
- Panasonic Lumix G2 - 17x13mm sensor - good in low light but not as good as the Sony but then the sensor is smaller with more pixels. Lens optically stabilised.
- HTC One phone - 1/3" sensor - actually very good in low light and on auto was better than the Lumix G2 on auto! I have some very good photos from our holiday. Lower pixel count means photos are not as detailed of course. Relatively fast F/2 lens and there is optical stabilisation.
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As Zero says above, very high megapixels are not needed if viewing on a screen or you need to do serious cropping. When i read reviews of say the latest smart phones the review will do some 100% crops to show one phone is lacking detail. Except the original photo looks fine on the lower resolution phone.
The latest 4K Ultra HD TVs are 3840 pixels × 2160 lines (8.3 megapixels)... how many of us have one of those?
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>> Re pixels are they a physical thing that made onto the chip then when you
>> reduce resolution in the camera menu you only use some of them?
No. They are a physical thing, but they all get used.
The raw data off the chip are unchanged, and come from all the pixels. Software that produces the lower resolution image just averages and smooths the data into a smaller number of pixels.
You will always have the best potential image from using all the resolution the camera offers. The nuance being the interpolation thing - I have a 3MP Fuji that produces 6MP from a 3MP chip, which does improve them slightly by making them less blocky if they are heavily cropped, but adds no resolution.
The other option on quality is the file size. JPG is a compressed format that sacrifices data and ultimate resolution. In a high quality jpg this is unnoticeable, but if you make the file sizes too small then you will see the loss of definition and colour gradation.
Finally - there is a way to use fewer pixels but it doesn't help at all. That is digital zooming. That confers no extra benefit to the image than just cropping the image you would get if you just used the maximum opticalzoom. Some cameras automatically use digital zoom when they run out of optical zoom. I always switch that off if I use one. You might take a different view if it is video of course.
It isn't the number of pixels that causes the small sensor/too many pixels 'problem'. It's the size and proximity. Light does funny things when you start messing about with it on that scale (a technical explanation that works for me).
Last edited by: Manatee on Tue 25 Jun 13 at 10:23
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Have a look at various sensor sizes. Bigger sensor, better the image quality.
en.wikipedia.org/wiki/File:Sensor_sizes_overlaid_inside_-_updated.svg
Unless you are getting a DSLR, it might be worth getting an APS-C compact digital. They are pricey though.
Last edited by: movilogo on Tue 25 Jun 13 at 11:03
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OK understand the pixel count/sensor size thing now thanks.
The problem is that it's hard to avoid excessive pixels in the superzoom and bridge cameras because the ones that have all the features I've come to expect/need seem to be 12/14/16mp.
Shame they don't make an up to date fully featured camera with a sensible 8-10mp.
Other point seems to be the huge variance in the way different makes/model process these imperfect over-pixelled images with their internal software... some have the noise reduction process nicely balanced and others ruin the images with it.
It's a fair point thinking back to the old 35mm days saying framing skills are lacking if you need to crop a lot but digital and media use of images has expanded to a degree where it is very useful to be able to heavily crop an image taken for record purposes or promotional/sales use rather than art.
Last edited by: Fenlander on Tue 25 Jun 13 at 11:51
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Camera Corner - Noise vs pixels advice - rtj70
