It is currently Sun Nov 23, 2014 6:37 am

Forum rules


No more than three images or three external links allowed in any post or reply. Please trim quotations and do not include images in quotes unless essential.



Post a new topicPost a reply Page 3 of 4   [ 53 posts ]
Go to page Previous  1, 2, 3, 4  Next
Author Message
 Post subject: Re: Megapixel race still on
Unread postPosted: Tue Nov 06, 2012 5:40 pm 
Subsuming Vortex of Brilliance
User avatar

Joined: Fri Sep 26, 2008 10:48 pm
Posts: 3273
Well it's open to debate I'm looking at the basics here (and I think Nikon don't do well at this price point) but I need off camera flash, I absolutely need HSS stuff like that. Even for an OVF the 0.78x mag is frankly embarrassingly poor in this day and age (I'll give a nod to Pentax for the K-30's decent OVF at a new low price), and then you add in the "won't AF" on older lenses and even if I still thought Nikon were great, I'd run a mile from this offering. Maybe others won't be as critical I feel Nikon lack some very simple things, and it harks back to their 35mm SLR days.

Someone gave me an F55 for free and frankly the Dynax 5 stomps it hands down.

Back to the sensor Nikon France have some samples up
http://www.flickr.com/photos/nikonfranc ... 942703170/

I'm not overly impressed some hot pixels and not that impressive in low light. They've use capture NX to process them but the low light ISO 3200 shot is poor IMO, maybe badly processed but nothing really stands out at least in that set of shots.

As for metering it looks like the recent Nikon's are following the D7000 trend which is an over bias on the AF point (not quite D80 madness) but end result I found is that it could grossly overexpose (black suit shot) at times, and it can be easily fooled with strong back-lighting, to be fair any metering system has it's quirks. I preferred the D90 metering myself a bit less biased to the AF point and more balanced overall exposures. I completely understand the more exposure at high ISO concept def helps for IQ there, but too hot for my own tastes in normal lighting.

I'd tremble with fear with the D7k's AF system and no fine tune in this body..but maybe they will calibrated them properly!


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 11:59 am 
Viceroy

Joined: Wed Oct 22, 2008 7:41 pm
Posts: 1198
David Kilpatrick wrote:
If the 5200 is similarly ahead of the A77/NEX-7, as the D600 is ahead of the A99, it will be attractive for tele wildlife, safari, concert gigs etc. It should be fully useful at 3200. So not an uninteresting camera.

That 5200 is more likely to have the 3200's sensor, which is not from Sony and is a bit inferior.

Also, the Nex7 is not the same as a77, it's actually better at delivering a much wider usable-quality DR (which is not the same as measured by DxO). I only wish it had about 100Mp instead of mere 24, as there clearly are some lenses deserving that.

Here's an example, full image and a 100% corner crop together with the developing parameters, all NR off, ISO100, f/11 -


Attachments:
DSC03213.jpg
DSC03213.jpg [ 233.76 KiB | Viewed 659 times ]
DSC03213-2.jpg
DSC03213-2.jpg [ 166.83 KiB | Viewed 855 times ]
tone.jpg
tone.jpg [ 19.26 KiB | Viewed 855 times ]
Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 12:19 pm 
Subsuming Vortex of Brilliance
User avatar

Joined: Fri Sep 26, 2008 10:48 pm
Posts: 3273
Evidently the sensor is not the same as the D3200 one. Too early to call yet but I think 24mp is pushing it a bit on APS-C anyway. They might say it's "not from Sony" but we know from previous sensors most of them are Sony ones with "Nikon" tweaks or built to spec etc etc.


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 12:44 pm 
Viceroy

Joined: Wed Oct 22, 2008 7:41 pm
Posts: 1198
bfitzgerald wrote:
Too early to call yet but I think 24mp is pushing it a bit on APS-C anyway.

A 24Mp Bayer means only 6Mp full-colour dots. That's absolutely not enough res to correctly reproduce strongly coloured parts of the image, like the thing you see in the very middle of my sample. Moreover, the more sensels are there on the sensor, the less res must become victim of LPF; and if you then downsample to 1/4 of full pixelcount, you get much higher res/acuity than from a 1/4 Mp-count sensor. Just try looking at 24 to 6Mp downsample wrt a real 6Mp of some old DSLR - the diff is huge, especially in real print.


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 12:56 pm 
Subsuming Vortex of Brilliance
User avatar

Joined: Fri Sep 26, 2008 10:48 pm
Posts: 3273
Hence as I said some time ago..
This will replace bayer

http://www.sonyalpharumors.com/next-son ... ke-patent/

Bayer is running out of steam and they are running out of pixel space too
I personally think the pursuit of resolution by makers is a paper tiger, Nikon are as bad as anyone esp since these lower end models are not well featured the pixel count is the only thing selling them.

It is clear though that sensor resolution is no longer being used to differentiate between higher and lower end models..that is the trend


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 2:13 pm 
Viceroy

Joined: Wed Oct 22, 2008 7:41 pm
Posts: 1198
Bayer or not - doesn't matter. What matters is that the current sensors are the limiting factor of the system resolving power.
And whenever the res is not limited by the lens, there is always some scenario making the captured image look unnatural. And then you have to blur it further.

Hence we really need much higher resolution at capture. Then you may lower it in the output according to the specific practical needs, which needs may differ.


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 2:30 pm 
Subsuming Vortex of Brilliance
User avatar

Joined: Fri Sep 26, 2008 10:48 pm
Posts: 3273
I don't think we do need "much higher resolution" the multi layer colour sensor makes sense to me.
How many people are unhappy with 12-16mp output? You can print pretty big with these sensors.

Otherwise we'll end up with 100mp FF bodies, and 50mp APS-C ones if not more. Fancy chewing through the raw files on that do you?
For many people even the 36mp of the D800 is inappropriate for their needs (def overkill for wedding photographers) and with no small raw either you're forced to eat up tons of card space and wrestle with 36mp files. 24mp FF would be overkill for me..16mp APS-C is more than enough for any task I would throw at it..in fact 10mp was enough too.

Still use the 6mp ones as well for some stuff.
More is not always better. It's marketing and sales nothing more


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 2:50 pm 
Viceroy

Joined: Wed Oct 22, 2008 7:41 pm
Posts: 1198
bfitzgerald wrote:
Fancy chewing through the raw files on that do you?
As I was saying above, the output is not necessarily the same as capture res.

So do capture at 200 with no LPF, bin down the raw data right on the sensor to 50-22-13-8, all depending on the needs. And 36Mp of the 800 is quite inappropriate as may be binned down only to mere 9Mp, and atop of that it needs a strong LPF.


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 6:29 pm 
Tower of Babel
User avatar

Joined: Sun May 27, 2007 3:25 pm
Posts: 6136
Location: Townsville, Qld. Australia
Agorabasta ol chum do you have absolute confidence in downsizing algorithms binning exactly so that the finished size reduced file is not damaged in any way? From what I’ve seen often there is quite a bit of artistic licence and artefacts to be had so I sort of have my doubts, but there is always a chance for improvement I guess.
Greg
Ps The question I’d like answered is what exactly takes place when I view a 24megapixel image (if I had a camera that produced one that is) on my 2.3megapixel monitor; (never mind a 100Mp one).
Also with printing as far as I know there is still the 8bit sRGB gamut (usually) in play unless you send a 16bit adobe RGB file to the printer driver then the colour space is big and finely stepped IF your printer driver can handle it properly as per the colour profile, but from what I’ve read it’s probably no big advantage most of the time.


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 7:06 pm 
Viceroy

Joined: Wed Oct 22, 2008 7:41 pm
Posts: 1198
Greg,

The best down/up-sampling I've ever seen is found in Lr3/4 scaling function. It would seem, they work directly from the raw data by vector projection onto the output bitmap. Btw, without that they wouldn't be able to do any geometry corrections without losing too much resolution. So that's what they do, no doubt.

Here's a sample 100% crop from the same image as above in the thread, now after 50% linear downscale in Lr4; this time with lower 0.5p radius sharpening inside Lr (the former crop was sharpened at 0.7p amount=100 detail=7) and exact same 'low' sharp for 'screen' at JPEG export (bet you never saw better res in a 6Mp DSLR frame, even after the overcompression to meet this site's regulations) -
Attachment:
DSC03213-3.jpg
DSC03213-3.jpg [ 243.38 KiB | Viewed 812 times ]


Your question on what's happening if you look at an image downsampled in the viewer software or in the printer rasteriser - well, it all depends on the quality of those.

P.S. Edited to add sharpening to the image so that the comparison is more valid now.


Last edited by agorabasta on Wed Nov 07, 2012 8:01 pm, edited 2 times in total.

Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Wed Nov 07, 2012 7:53 pm 
Viceroy

Joined: Wed Oct 22, 2008 7:41 pm
Posts: 1198
As to the simple binning possible on the sensor chip, those are the square 2x2-3x3-4x4-5x5 bins, the 2x2 and 4x4 don't even need any further demosaicing. They are quite straightforward and may be done by on-chip wiring, may be even done before the readout by short-circuiting the groups of sensels.


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Thu Nov 08, 2012 3:24 am 
Tower of Babel
User avatar

Joined: Sun May 27, 2007 3:25 pm
Posts: 6136
Location: Townsville, Qld. Australia
It does look surprisingly good indeed especially the furthermost of the leaves, but is it my ageing eyes? it looks sort of like it needs to be degaussed or something like that, it’s probably just the sharpening over the slightly oof area of the image that it was taken from perhaps. But in any case I’m not sure if that is a productive endeavour to justify large megapixel count sensors, i.e. looking at bits and pieces of the original composition, if that is the item of interest (in the crop) why not just take the photo of that in the first place?
I do most certainly agree that doing that exercise tops what you can do with a 6Mp camera but by the same token if you were to take the area of the crop with a 6Mp camera and a decent lens I think you would be surprised at the quality you could obtain just the same.
Greg
Ps the problem of downsizing (as far as I know, but LR could be different) is in the vector-bitmapping process the image colour gamut is converted to 8 bit at the same time thus loosing the 16 bit advantage in the colour space of the original image.


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Thu Nov 08, 2012 11:37 am 
Viceroy

Joined: Wed Oct 22, 2008 7:41 pm
Posts: 1198
Greg Beetham wrote:
Ps the problem of downsizing (as far as I know, but LR could be different) is in the vector-bitmapping process the image colour gamut is converted to 8 bit at the same time thus loosing the 16 bit advantage in the colour space of the original image.

Lr is really different, there any no intermediate pixel states between the raw and final output, there are only the dynamic functional dependencies projecting the raw data onto the output bitmap pixels, and the 'granularity' of those functional dependencies is much finer than that of the raw data, so it's essentially smooth. So there's nothing like 8/16bit limitations.

Adobe themselves have always stressed that Lr is not a 'pixel-based' editor, and they seem to really stick to that.

But you don't need any fancy Lr processing for doing a simple square binning over the in-cam raw.


Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Thu Nov 08, 2012 12:14 pm 
Viceroy

Joined: Wed Oct 22, 2008 7:41 pm
Posts: 1198
Greg Beetham wrote:
It does look surprisingly good indeed especially the furthermost of the leaves, but is it my ageing eyes?
That leaf gets light almost directly from above, it's the midday sun shining through very thin translucent cloud layer. A very special light, hence the picture.
Here's that leaf at 100%, some haloes on the leaf edge are from extreme tonal compression and not from sharpening -


Attachments:
DSC03213-4.jpg
DSC03213-4.jpg [ 129.39 KiB | Viewed 778 times ]
Top
 Profile  
 
 Post subject: Re: Megapixel race still on
Unread postPosted: Fri Nov 09, 2012 3:56 pm 
Tower of Babel
User avatar

Joined: Sun May 27, 2007 3:25 pm
Posts: 6136
Location: Townsville, Qld. Australia
I’ve been thinking agorabasta, maybe a good test the downsizing method would be to try it on the sky transition problem and see it that improves the ragged transitions that occur when downsizing the jpeg for the web, they could already be there in the file from the start of course but seem to be vastly improved if the size is kept too at least half a megabyte, too big for this site though. I don’t think I can do it with a RAW file using Elements but it should be possible with a .dng which I’m fairly sure would preserve the 16bit colour. Ideally perhaps you should try it with LR if you have a good sky photo fading from deep blue to light blue, it might help solve the mystery about the origin of the bad transitions.
Greg


Top
 Profile  
 
Display posts from previous:  Sort by  
Post a new topicPost a reply Page 3 of 4   [ 53 posts ]
Go to page Previous  1, 2, 3, 4  Next


Who is online

Users browsing this forum: No registered users and 0 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  


Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
twilightBB Style by Daniel St. Jules of Gamexe.net