[Ben_Edict]

"help to reduce the CA."

A curved sensor wouldn't affect CA in the slightest. Yes, the lenses in compact cameras are bad, compared to SLR designs..but because they are so small the tolerances have to be extremely high to produce a quality product...and that just isn't possible when P&S cameras are experiencing a reduction in market size due to the increase of EVIL cameras, and low priced entry level DSLR cameras.

The problem with these small lenses is not so much production related (tolerances etc.). There is basic constraint: The resolution of a lens is limited by its diameter - nothing else. If the diameter of the lens gets smaller, the resolution goes down unavoidably (Rayleigh-criterion). There is no circumvention.

Now, combining a lens with a low resolution with a small sensor with high pixel density is a bad idea, because the resolving power will not make use of the pixel count. That is, why most 12MP p&s cameras will not show more detail, than a 7 or 8MP cam.

Then ofcourse add the other detrimental side-effects of small sensors (limited dynamic range, higher noise), and the whole compact package is destined to lack IQ. It is more astonishing, that these cameras produce acceptable to good images (printed int the standard small sizes) at all!

Ben

[Digitalis]

I agree with you there Ben, additionally you also notice when an image has been taken with a camera with a larger sensor. Like the difference between 35mm and 67 format - you can see the quality.

[Ben_Edict]

.. additionally you also notice when an image has been taken with a camera with a larger sensor. Like the difference between 35mm and 67 format - you can see the quality.

That is very true, though I am always quite astonished how good the current DSLRs really are. 35mm film is not really an alternative anymore, one must go bigger for a marked improvement.

Ben

[Digitalis]

you also notice it against full frame against medium format in the digital world. The 44X33mm sensor in the upcoming 645D will produce image quality that is superior to full frame.

Digital medium format has yet to catch up to 8X10 IMO the DoF effects my ebony 8X10 view camera can achieve are astonishing. Not to mention the range movements that I have access to. Additionally, I can produce platinum/palladium prints* something that is difficult to do with digital these days, and even if you do manage; it does not look the same...the images look too linear**( at least with the prints I have seen with my own eyes).


*I have been working on platinum for an upcoming retrospective exhibition of my 8X10 view camera work, alongside some of my grandfathers 8X10 and 4X5 work which he never lived long enough to print.
**though I have seen some impressive results using pieziography on fiber based Baryta papers from ilford

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Last edited by Digitalis; 05-20-2010 at 04:54 AM.

[Ben_Edict]

Yes, digital MF is a real step above any FF camera and the latest generation of 40MP+ backs and cameras have widened that gap again. Unfortunately until the release of the Pentax 645D the price gap is also considerable.

What I find more important about larger formats, than just resolution, is the better, smoother tonality. That is true for film and for digital.

In terms of printing, one step to consider would be to produce intermediat LF negatives with a good inkjet printer and then make your platinums from those. Something I'll give a try in the coming months, though I stick with my small 4x5 - and then the digital intermediate has the added advantage of not needing an enlarger for the big negs. That's nowadays not a question of cost anymore, but these LF enlargers need so much space!

Ben

[Digitalis]

I have been working with pieziography for my digital work, the tonal range is truly astonishing with the Seleniumn/sepia mixed tone set of inks you can achieve results that are similar to platinum/pallidum prints. I have tried the digital inter-negative process with my work in platinum but I didn't like some of the issues I encountered with print density. A lot of printers have problems laying down so much of ink on a substrate that is only capable of absorbing so much of it without it smearing. I contact print in platinum, I know they say slight enlargements are sharper, but no one I know of in Adelaide has an enlarger that can handle 8X10.

[pingflood]

I disagree. The high pixel density leads to problems with DR, noise, and diffraction starts early

Well, let's keep in mind that diffraction affects the potential resolution of the system; a small 100mp sensor is not going to be more "diffraction prone" than a 10mp one assuming the same level of magnification.

[er1kksen]

Well, let's keep in mind that diffraction affects the potential resolution of the system; a small 100mp sensor is not going to be more "diffraction prone" than a 10mp one assuming the same level of magnification.

No, it's not, and I didn't mean to say that it would. I meant that diffraction was limiting the resolution because additional pixel density won't return any appreciable detail past the practical diffraction limit of the lens's largest aperture, and thereby be yet another of the factors limiting the resolution you can get from lenses on such small sensors.