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Fun With Sony Cameras

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barjohn

New member
Re: Fun with the NEX cameras....

Do I understand you to think it is a firmware issue? It seemed like some speculated about issues due to AA filter spacing, etc. If it is a firmware issue how is it manifesting itself in RAW images? Is it the demosaicing (not sure of spelling here) algorithm?
 

barjohn

New member
Re: Fun with the NEX cameras....

Can you post a shot taken with G1 and NEX of same object so we can see the difference you are talking about and maybe make the RAW images available for us to try our hand with different converters.
 
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Vivek

Guest
Re: Fun with the NEX cameras....

Can you post a shot taken with G1 and NEX of same object so we can see the difference you are talking about and maybe make the RAW images available for us to try our hand with different converters.
I will do the first part (you can already see the mush from the NEX/ SOM-Berthiot shot in this thread. Just imagine the fuzzy areas being sharp when the images are taken with a G1. If still in doubt, check out my images posted in the 4/3rds forum). Sorry, I do not share any large images and certainly no RAW files with anyone.

I have no idea if it is a hardware problem or a software fix is possible. All I do know is that the NEX is not all that useful, as is.
 

roweraay

New member
Re: Fun with the NEX cameras....

That (weak AA and moire mush) is a possibility.
Moire is a consequence of weak (or no) AA filter. Obviously, it does not manifest itself in all pictures and only in portions of the picture with repeating patterns....like in the stadium picture referenced in the other thread. Fabrics (with fine lines etc) are another area where one can see moire readily. And removing moire after the fact is simply not possible.

The upside from a weak AA filter is natively sharp(er) pictures than ones with strong AA filtering. Pick your poison.
 
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Vivek

Guest
Re: Fun with the NEX cameras....

The problem is lack of sharpness and that comes from aliasing.
 

douglasf13

New member
Re: Fun with the NEX cameras....

I'm confused by this. Everyone is saying that the NEX has more resolution than its predecessor Exmor cameras, and the aa filter is relatively weak. Are you saying the opposite, Vivek?
 

roweraay

New member
Re: Fun with the NEX cameras....

The problem is lack of sharpness and that comes from aliasing.
"Lack of sharpness" from having a weak AA filter is a new one for me ! ;) I would have expected the exact opposite to have taken place. Aliasing results in moire when encountering repeating patterns and that is about it. If anything, not having a thick AA filter would result in sharper images, at the expense of moire in conditions that make it visible.

I think you are confusing the optical problems encountered when pairing these lenses with the NEX sensor and associating that with "aliasing".

I will take a few pictures with my A-mount lenses (Carl Zeiss etc) and do a comparison with the kit lens and see what comes up. Without even going through with the test, I can say that the A-mount CZ lenses will reveal the full potential of the sensor, unlike the cheap kit lenses that come paired with the NEX5 and/or taking images with hit-or-miss RF lenses. Aliasing has got nothing to do with lack of sharpness, as far as I know.
 

barjohn

New member
Re: Fun with the NEX cameras....

VIVEK,

I can't figure out what you are saying unless it is lens related. Below is a side by side comparison shot from a tripod, same distance from subject with 18-55 and 40/2.



Now here is a 100% close up of center of image showing the difference between lenses. Lighting and everything else was the same other than the 40/2 was shot at f2.8 so shutter speeds are different.



These were converted in LR 3.2 RC with default sharpening at 25.
 
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Vivek

Guest
Re: Fun with the NEX cameras....

Aliasing results in moire when encountering repeating patterns and that is about it. If anything, not having a thick AA filter would result in sharper images, at the expense of moire in conditions that make it visible.
Do you see that part as contradictory?
 

barjohn

New member
Re: Fun with the NEX cameras....

That makes perfect sense to me and does not seem contradictory. An AA filter introduces optical blur. It is the whole reason the M8 and M9 can claim to produce sharper images than many DSLRs. The cost for the additional pixel sharpness (contrast) is that moire can become evident with repeating patterns.
 
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Vivek

Guest
Re: Fun with the NEX cameras....

John, Thanks for your test shots.

Let us recap what is being discussed and what the source is- a hand held macro shot with a known performer was lacking in details. I did say (in response to Douglas) that I will have to check if my set up was stable (shake) despite the high shutter speed. Douglas quoted a thread from elsewhere that does address one possibility. Demoscaing (that Douglas pointed) is one.

DRO is a definite contributor.

Noise reduction (at high ISO) that goes on in camera is another (anyone knows if that can be switched off completely?).

Moire is an optical blur (blemish if you wish to call that).

Bees and flies do have lots of fine structures.
 

roweraay

New member
Re: Fun with the NEX cameras....

Do you see that part as contradictory?
Yes, I very well do.

"Sharper Images" when Moire is absent (which accounts for a majority of images where repeating patterns are not very prevalent) and even in Moire affected images, the portions of the image (without closely repeating patterns) that are unaffected by moire, will be sharper with a weak AA filter than with a thick AA filter.

"Moire" and "sharpness" are not related. The Leica M9, with an absent AA filter, is never considered as "unsharp" due to being affected by Moire.
 
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Vivek

Guest
Re: Fun with the NEX cameras....

Yes, I very well do.

"Sharper Images" when Moire is absent (which accounts for a majority of images where repeating patterns are not very prevalent) and even in Moire affected images, the portions of the image (without closely repeating patterns) that are unaffected by moire, will be sharper with a weak AA filter than with a thick AA filter.

"Moire" and "sharpness" are not related. The Leica M9, with an absent AA filter, is never considered as "unsharp" due to being affected by Moire.
:)

Well, I do not think we disagree.

The example you quote results in "too sharp" images and not "unsharp".. :)
 

BackToSlr

New member
Re: Fun with the NEX cameras....

John, Thanks for your test shots.

Let us recap what is being discussed and what the source is- a hand held macro shot with a known performer was lacking in details. I did say (in response to Douglas) that I will have to check if my set up was stable (shake) despite the high shutter speed. Douglas quoted a thread from elsewhere that does address one possibility. Demoscaing (that Douglas pointed) is one.

DRO is a definite contributor.

Noise reduction (at high ISO) that goes on in camera is another (anyone knows if that can be switched off completely?).

Moire is an optical blur (blemish if you wish to call that).

Bees and flies do have lots of fine structures.
Vivek and Roweray,

Moire is not an optical blur, but an interference pattern. It does result in loss of details. It has nothing to do with sharpness but rather amount of detail present in the picture. In digital domain, it happens on account of sampling below the Nyquist frequency (or undersampling) for that particular SUBJECT. Typically a low pass filter is used to eliminate the interference (this can be done by optical or digital filters, principal is the same, optical ones also reduce the light to sensors, digital ones result in floating point errors on account of not enough precision being used in computing the transform).

On subject of NEX-5 having loss of details on macro lenses, i have not yet observed it. I am also puzzled by BarJohn's results so i tried a quick test wit kit lens and 50 macro both at 50mm, f8. FOV is a bit different as expected for different focusing elements. My kit lens certainly does not show distortion anywhere close to his.







Kit lens seems to a bit of sample variation.

Cheers,

N
 
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Vivek

Guest
Re: Fun with the NEX cameras....

N,

Interference -> lack of details -> this I equate to mush (or "unsharp" or "too sharp").

Yes, personally I am quite familiar with Moire (I used to image rows of atoms and such elementary things using electron microscopes), even before I took up digital photography.

Your definitions and explanations (of moire) are succinct.:)

On John's test images (here and in other threads), his kitzoom appears to be problematic indeed.
 

barjohn

New member
Re: Fun with the NEX cameras....

Based on the feedback here and my testing I am sending it back to Sony for replacement. It definitely is not even close to the 40/2. I ran additional tests at 18mm, 24mm, 28mm, 35mm and 55mm at f8, f5.6 and f4.5 and I find the lens is sharpest at 18mm and terrible at 55mm. The changing of the f stop did not make a significant difference.
 

jonoslack

Active member
re: Fun With Sony _____

Great shots guys
Dave. Love the Monterey shots
MG the spooky skull works well
Bill the little girl shot is splendid
Bill. The spider shot really sparkles. I hadn't thoughtnof the sigma macro. What is the focusing like?
 

peterv

New member
Re: Fun with the NEX cameras....

John, Thanks for your test shots.

Let us recap what is being discussed and what the source is- a hand held macro shot with a known performer was lacking in details. I did say (in response to Douglas) that I will have to check if my set up was stable (shake) despite the high shutter speed. Douglas quoted a thread from elsewhere that does address one possibility. Demoscaing (that Douglas pointed) is one.

DRO is a definite contributor.

Noise reduction (at high ISO) that goes on in camera is another (anyone knows if that can be switched off completely?).

Moire is an optical blur (blemish if you wish to call that).

Bees and flies do have lots of fine structures.
Is that it?

Man, you guys are discussing this as if you just spend €40.000 on a 60 MP Phase back, Alpa 12 SWA (Rosewood) and some Schneider glass and now you're getting 'mushy' results.

The last ten or so comments above make it sound like the NEX is a seriously flawed camera. It's a €650 APC point 'n shoot for crying out loud.

As I tried to make clear in response to Douglas' links to the Alphamount guys, my personal opinion is that there's far too much pixel peeping going on with the NEX. Now don't get me wrong, I find this technical stuff intriguing, but I just don't think these questions and often cryptic answers belong in a thread called 'Fun with...'

Me, I'm enjoying my NEX 5 more and more as just that. A fun point and shoot with good enough results for prints up to 30 x45 cm if by chance there's something worthwhile between the daily snaps.
Shoot first, think later. To me that is a very welcome alternative to my Leica MP, M7 and serious a900 work.

Kind regards,

Peter
 
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