Photoclubalpha

I've now made enough comparisons to conclude that very little has changed with Nikon versus Sony on the high ISO - or indeed entire ISO - front.

When I compared the D3X with the A900, I found that what Nikon was calling 1600 and exposing for X at X was in fact what Sony called 800, and gave exactly the same exposure.

The same situation applies to the D600 versus A900. Typical examples - same subject, same position, same time - A900 gives 1/320th at f/8 ISO 800, the D600 gives 320 f/9 ISO 2500. The D600 image is more fully exposed, by around 0.7 stops in real terms, meaning the Nikon is really delivering ISO 1600, exposing for ISO 1000, but claiming it's at ISO 2500.

This is confirmed by checking headroom; in the standard Nikon pictures, it's not unusual for areas of bright or plain sky to show a clipping warning in ACR, and if the brightness or exposure are adjusted to remove this, the picture becomes as dark in the shadow areas as the Sony result. In the Sony raw files, an exposure increase of 0.7 to 0.9 stops is usually needed to make light areas begin to clip to the same degree that 'standard' Nikon files do.

Notwithstanding with, the D600 files at any ISO over 400 show significant detail and noise improvements over A900 and the improvement becomes more marked as the ISO is increased. Once the 'fake ISO' aspect is taken into account, I'd say there is a true improvement of 1 to 1.25 EV; because the D600 effectively overexposes, it appears to have a benefit of 2 EV or slightly more.

So, if comparisons appear between A99 and D600, this discrepancy should be taken into account. ISO/noise comparisons are only like for like if the exposure is identical and this is not the case.

David

Interesting comments, and suggestive perhaps that image sensor capability has reached a plateau pro tem.

But surely we should be comparing the a99 with the D800, not D600, since the premium Nikon is still selling at a lower price than the a99?

Like sensor for like sensor - all 24 megapixel. The D800 sensor performance is entirely different, and while it's better than the A900 pixel for pixel, it's not as 'good' as the D600. The A99's price is not relevant, it's quite seriously overpriced which is one reason I'm slightly unwilling to buy one. Also, I find the EVF overlays for the advanced focusing functions are quite intrusive.

However, I have not used the D800 and D600 together and been able to compare the real exposure they give for any set ISO.

David

Most of the Nikon's I tried gave more exposure at high ISO, esp the D7000 which would sometimes give too much clipping highlights at times.
I'm not surprised by the fake ISO levels, question remains how accurate other models are.
I still think the Km5d I have is quite close to actual ISO levels..though you would not really want to use it at ISO 3200

David Kilpatrick wrote:Like sensor for like sensor - all 24 megapixel. The D800 sensor performance is entirely different, and while it's better than the A900 pixel for pixel, it's not as 'good' as the D600. The A99's price is not relevant, it's quite seriously overpriced which is one reason I'm slightly unwilling to buy one. Also, I find the EVF overlays for the advanced focusing functions are quite intrusive.
David

A99 might be overpriced in the UK, in the US it's $400 cheaper than 5D Mark III and $200 cheaper than D800.

Canon 6D and D600 are lower spec cameras.

I've now got an A99. I can confirm that things are much as I thought; the A900 is actually better than the A77 by a considering margin (which I did not realise, as I had never used the A900 at high ISO where the A77 has ended up being used that way a fair amount). The A99 is better than the A900, and worse than the D600.

However, we don't want two D600s, and I have decided I do not want a D800. I'm fed up with become slightly agitated, even angry or frustrated, by the conflicts between the cameras I own; trying to pack up for a trip or even just decide what to take for a few hours looking for subjects. Reasons like - full frame vs APS-C, 24 megapixels or 16, one convenient zoom versus a bag of lenses, portability of NEX versus DSLR, and so on.

A99 solves that. It's so expensive all the rest has to be sold. So the choice is removed and I no longer worry. It has 24 megapixels, it has GPS, it makes full use of some lenses I like. The only single downside is that there's no such as a walkaround zoom lens for it.

David

David Kilpatrick wrote:The only single downside is that there's no such as a walkaround zoom lens for it.
David

Hi David,

Don't Tamron still do the older non-VC 28-300 in Sony mount? Can't speak for it being any good or not.

David Kilpatrick wrote:The A99 is better than the A900, and worse than the D600.

No doubt it is so.
The 99 must be worse than the 600 at least by 1/3EV plus the rather aggressive raw filtering in the 600. But that filtering must be off at ISO1600. I think they must be compared there and at the lowest ISO.
The raw filtering in the 600 has the same affect as a simple threshold filtering over a bilinear-demosaiced green channel, then storing the 'best' values for the original green sensels. Not quite raw, but works pretty well.

Tried Tamron and Sony for walkaround zooms 28-300mm - discontinued. Nikon's lens is f/5.6 at the long end and surprisingly good optically, but suffers from so-called 'focus breathing' (not a term I like) which means it's really only a 150mm at close-up range.

I don't really care what Nikon does with the raw file, it is the end result which counts. Shirley has very bad shooting habits, always trying to catch shots in low light. I am OK without ever going near 6400.

I was sad to pack up the A900 today and sell it on. I look at the low ISO images, and the only way I can describe it is that the pixels 'join' to make a smooth image, with plenty of colour and depth. I am not entirely sure the 'better' new sensor/datastream models do this. There was something about the A900 I will miss.

David

In fact I had an example to look at, I tried to send it to the buyer but PM would not allow it and I have not been able to change the admin settings for pms to allow jpegs to be attached. Here it is: And here is a 100% section - I also sold the quite lovely 28-135mm which produced this. I probably won't find another like it and I only owned it for a month! I don't think the A99 will do the same. It also does not feel the same in the hand. But I will get used to it.

David

Perhaps use the A99 in crop mode and the CZ16-80 or 18-250DT?
The only other realistic ff choice in Sony lenses (heavy in more ways than one) is the limited range for a walkabout CZ24-70.
The Sigma 28-300 is reviewed here http://www.ephotozine.com/article/sigma ... eview-4347 the close focus is good and the first half of the zoom range is ok according to them.
This guy uses a Tamron 28-300 for weddings on a 5D http://digitalprotalk.blogspot.com.au/2 ... mm-vc.html you can judge for yourself on that.
Greg

David Kilpatrick wrote: I don't really care what Nikon does with the raw file, it is the end result which counts.

Well, I also think the result is quite good.

My point is that it's a result of preprocessing that may be done as well in a software developer. If such preprocessing gets included in a commercially viable proggie like Lr/ACR, the tables may turn since that in-cam preprocessing is really too simple and can be done better with external processing.

Looking into the available raw samples, I find a striking similarity in raw quality between the earlier D3X and a99. And those pro bodies always had laxer levels of raw filtering compared to the consumer bodies, and D600 is clearly positioned as a consumer product.

"And here is a 100% section - I also sold the quite lovely 28-135mm which produced this. I probably won't find another like it and I only owned it for a month!"

But why? I keep lenses if they perform well. My 24-85mm Minolta circular aperture continues to surprise me on my A900, I bought it when I had a 7000i and 9xi in use. the last new Minolta lens I bought for very little money when everyone was ditching Minolta gear, sharp throughout the range and it does not add much more bulk or weight for walk round mode.

David Kilpatrick wrote: .... I'm fed up with become slightly agitated, even angry or frustrated, by the conflicts between the cameras I own; trying to pack up for a trip or even just decide what to take for a few hours looking for subjects. Reasons like - full frame vs APS-C, 24 megapixels or 16, one convenient zoom versus a bag of lenses, portability of NEX versus DSLR, and so on.

David

I have that dilema and I only have APS-C
Take only the 18-250 and suffer the relatively poor IQ or go for a better 2 lens system with the 16-80 and long zoom.
Ah but then which long zoom, the compact 70-300 Sigma or the heavy/bulky 70-200G.
I won't even discuss the 70-400G option.....

It never ends!
I'm glad I don't have full frame as well (or am I ??).
Your timing was excellent as I had no money to even think of making an offer for the A900.

Mike

David Kilpatrick wrote:In fact I had an example to look at, I tried to send it to the buyer but PM would not allow it and I have not been able to change the admin settings for pms to allow jpegs to be attached. Here it is:

And here is a 100% section - I also sold the quite lovely 28-135mm which produced this. I probably won't find another like it and I only owned it for a month!
David

Don't worry David, your A900 and 28-135mm are going to a good home which has been in the Minolta/Sony faith for a long time... they'll be welcomed by a 35F2, a 100F2, a 200F2.8 and a few younger ones, all of which have been in the familty since they were came to life ... and very few have left (an adopted 9000 mated to a 28-85mm, 20 years ago)

Eiffel