It is currently Mon Nov 24, 2014 4:40 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 2 of 2   [ 23 posts ]
Go to page Previous  1, 2
Author Message
 Post subject: Re: Reasons for buying a NEX-VG900 instead of an A99
Unread postPosted: Sat Nov 03, 2012 6:48 pm 
Subsuming Vortex of Brilliance
User avatar

Joined: Fri Sep 26, 2008 10:48 pm
Posts: 3273
I'll have to differ here as I've had precious few issues with lenses needing fine tuning in fact I can't think of any problems I had with A mount lenses. Yet both D7000's required AF fine tune for every single lens I put on it. With the D90's they had no AF tune so you were basically stuffed, that's why I sent it for service twice (first time front focus, second time back focus again) out of all 5 bodies none were what I consider to be at an acceptable level. And certainly not suitable for paid for work where the degree of focus errors is way too high. Slight errors in focus might not be an issue in the real world, all the Nikon's had quite a variation in focus in many cases to a shocking level (ie missing shots by feet and metres) Add to that the Nikon's almost never refused to lock (ie warn you if the contrast is too low to get accurate AF)

A57 no AF fine tune, but the 50mm f1.7 wide open nails it almost every time..it's in a completely different league to the Nikon's I've used a far superior more accurate AF. As much as I hate EVF's I hate out of focus shots even more.
There will always be the odd rogue lens, but IMO if you have to start using AF fine tune on lots of lenses and with hefty corrections, then there is something wrong with the calibration to start with. This seems all too common on Nikon bodies even the D800..kind of a DIY focus calibration which is not my idea of good.

I'd be fairly reluctant to spend £1500 on a camera that only has acceptable AF with one central AF point, but hey that's my take. I found all 39 AF points all quite hopeless in the 2 bodies I had. None of the settings helped much AF-C slightly improved, 3d tracking is only very useful in specific situations. I think I took over 1300 shots at a wedding with the D7000 (way over my normal number) and about 60% were binned due to poor focus. Out of the acceptable ones a good few had to go for some tweaking in focus magic. I just can't accept that level of poor focus, which is why I sent the D7k off again for service..and sold it.

I couldn't wait to get rid of it..I just need to get a refund off that one that went back to Amazon


Top
 Profile  
 
 Post subject: Re: Reasons for buying a NEX-VG900 instead of an A99
Unread postPosted: Sat Nov 03, 2012 7:41 pm 
Site Admin
User avatar

Joined: Sat May 19, 2007 1:14 pm
Posts: 6181
Location: Kelso, Scotland
You mean you were not using just the central AF point, in practical everyday work?

I've not found ONE camera where the multi-point system works well enough to be relied one. Sony's concept of 'zones' in the A77 is one of the best variants, with the three vertical zones.

I'm looking for focus accurate to the millimetre, not within feet or inches, and the D600 is delivering that just as well as the A77 or A580, or indeed the A900. Back focus problems with Alpha started with the KM7D and I was one of the first to try to method for adjusting the body myself, and writing it up; in the A100 and onwards, bad coincidence between the marked viewfinder AF point and the actual zone were added to the issue.

You've been very unlucky with Nikon. We have either owned or used for a reasonable periods many Nikons, every body since the original D100 in fact (but not the new 3200, 3100 etc series) including the 40, 60, 70, 80, 900, all 200s, all 1/2/3/4 series. Today I was processing some shots taken with the 300mm f/2.8 plus 2X TC on the D800 - a real challenge, action shots of a labrador splashing through the Tweed retrieving sticks.

My only error was to work at f/7.1 (just 2/3rds stop down from wide open with that combination) and ISO 200, the D800 would have been perfect at ISO 2000 in that light, but I didn't trust it.

Attachment:
nikondog-full.jpg
nikondog-full.jpg [ 142.99 KiB | Viewed 878 times ]

Attachment:
nikondog-600mm-100pc.jpg
nikondog-600mm-100pc.jpg [ 236.52 KiB | Viewed 878 times ]


Any softness is due to using a fast tele with a TC and not stopping down 2 stops - f/11 would have been better. This is the type of subject I routinely use for AF tests - this, or ducks taking off and landing on the same stretch of water. Plus indoor low light, outdoors at night, macro shots, landscapes with trees at 400 yards, etc.

I've had great results from many systems and individual cameras, and poor results as well. In the A57 Sony has produced a module actually much closer to a Nikon or Canon design than earlier arrays (all f/5.6, more cross sensors, no f/7.1 line sensors).

I actually need to calibrate our 16-80mm on the A77 as I've noticed that this is not doing exactly what's expected.

David

_________________
http://www.photoclubalpha.com
Image


Top
 Profile  
 
 Post subject: Re: Reasons for buying a NEX-VG900 instead of an A99
Unread postPosted: Sat Nov 03, 2012 8:59 pm 
Subsuming Vortex of Brilliance
User avatar

Joined: Fri Sep 26, 2008 10:48 pm
Posts: 3273
Well I was using mostly the central AF point, and single point AF as I usually do (regardless of maker or model) but I did try some of the "fancy" AF modes on the D7000 such as AF-C and various spreads of AF points, which had no impact on results.
I'd get a shot of someone... AF confirm only for the person behind them to be in focus! Hence my remarks about back focus on all the bodies. Even borrowing lenses (some of which is pro glass) I got back focus on every lens I ever mounted on the 5 Nikon bodies. And not "a tad of backfocus" quite a lot. Both D7000's the same

This was one test shot I did pretty easy for any phase detect AF system

Attachment:
DSC_5852.JPG
DSC_5852.JPG [ 154.85 KiB | Viewed 873 times ]


Not exactly on target now..the film scanner is about maybe 4-5" behind the tank IR target. I could adjust the AF tune so that it would be ok, but there was still a variation in focus that could not be explained. When it came to zoom lenses forget it entirely because no matter what adjustment you made it was still hit and miss. And if you started to use longer focal length lenses..not a hope you'd be able to use the AF fine tune to pull those in. If you made an adjustment on worst case back focus you'd end up with front focus in some shots

I took the same shot with the Km5d and it was on target. The original one I got in 2006 has proved mostly accurate for AF and has given little problems in this regard. The second one I got might need some adjustment, but it's not heaps off either. Granted not great AF for tracking subjects, the accuracy would drop off a bit in low light..but overall I didn't have many serious complaints about the 5d..not exactly fast but speed is only one factor.

K-x was ok for AF bar the big AF points..no signs of issues in low kelvin light either.
K-r has huge problems in specific lighting, but none in normal light (hence you can't adjust for that if you do your normal light shots are out) the AF adjust on that body was not able to correct the huge front focus, near 100% miss rate with that body in tungsten lighting frankly awful and a clear case of faulty AF module

None of the 35mm film bodies gave any serious issues for focus film 7, 60 and 5 seemed fine to me (and I can scan high enough res to see problems)

A200 was ok in normal light..but accuracy was a bit poor in lower light and that too had oversized AF points
D90's all 3 back focus, 2x D7000's same thing though they varied by how much.
I think it's a bit more than bad luck, honestly think Nikon have major QC problems. 5 bodies is quite a few to try without any success.

AF is never perfect, there are always variations it can lock onto subjects in the AF area that are higher contrast etc etc. But I think I have a pretty good idea of what acceptable is, there isn't a big margin of error..and if the body is out as much as the Nikon's were you'll never get satisfactory performance. Hence I felt 5 tries was more than Nikon deserved. That shot above is pretty shameful for any camera regardless of price, it's not even vaguely close. Huge miss..


Top
 Profile  
 
 Post subject: Re: Reasons for buying a NEX-VG900 instead of an A99
Unread postPosted: Sun Nov 04, 2012 10:15 pm 
Site Admin
User avatar

Joined: Sat May 19, 2007 1:14 pm
Posts: 6181
Location: Kelso, Scotland
Shirley has just done a few shots at the zoo today, mostly at f/9 to try to get a little depth of field, though this forced the ISO on the D600 up to 6400 nearly all the time (it was that bad, despite a hint of sunshine, Edinburgh Zoo is now not a good place to visit it's drab and run-down and you are lucky to see more than just a handful of animals).

Good to report that even in extreme conditions, the AF is really accurate with the 28-300mm VR. It's possible to tune the body with an overall over-ride, and then a different one for each lens. I need to spend some time to check it but there would be no need to do so on the basis of what I've seen.

For example, this image is a crop from a small section of a file, then resized - but it's as good as anything we have ever managed to get from the nocturnal-forest lighting of the marmoset house. This pygmy marmoset is about half the actual size you see it on the screen, and Shirley shot it wide open f/5.6 at 300mm, through glass, in lighting conditions which needed 1/30th at 6400 plus 2650K and +26 magenta to get anything remotely balanced.

Attachment:
pygmymarmoset-300mm-6400-5p6-30th.jpg
pygmymarmoset-300mm-6400-5p6-30th.jpg [ 205.31 KiB | Viewed 844 times ]


I was trying some A900 shots at the same time but really, got nothing. I did go up to 6400 but the A900 just doesn't do fur at 6400 in this light at this level of crop.

Difficult choice. Assuming the A99 is very similar in performance, I maybe should just keep the A700 for my studio product shots and trade up via the A900 and A77 to an A99 body and get the benefit of all the excellent lenses I've got.

One point - elsewhere dynamic range gets some mention. So far I do not think the D600 offers the same highlight recovery ability as the A900. I'm trying to work out how this relates to the ISO etc.

David

_________________
http://www.photoclubalpha.com
Image


Top
 Profile  
 
 Post subject: Re: Reasons for buying a NEX-VG900 instead of an A99
Unread postPosted: Tue Nov 06, 2012 1:11 pm 
Subsuming Vortex of Brilliance
User avatar

Joined: Fri Sep 26, 2008 10:48 pm
Posts: 3273
The Focus looks fine on that. I'm personally just very wary of Nikon now after my own experiences. Not to say I did not love some of their ideas and designs etc.
When you have so many AF problems with one maker it becomes impossible to have any faith in their products. If I had bought 5 iffy Canon's or Sony's the same would apply. My problems were on static or little moving subjects, so can't comment a lot on tricky ones. For me if a system has lots of consistency and accuracy issues I just walk away with easy shots causing problems! No idea why this is I have to feel it might be factory problems

I would expect the newer FF sensors to again show a leap over the later APS-C one for high ISO. If we look at the most recent CMOS APS-C sensor we can see they were probably doing better at low light than the older FF ones (ie A900/5dMkII) I wonder if makers will continue to push resolution so strongly 24mp on FF is ok, I can't say I'd want APS-C to go higher than that (but it probably will)


Top
 Profile  
 
 Post subject: Re: Reasons for buying a NEX-VG900 instead of an A99
Unread postPosted: Wed Nov 07, 2012 6:34 pm 
Tower of Babel
User avatar

Joined: Sun May 27, 2007 3:25 pm
Posts: 6136
Location: Townsville, Qld. Australia
Yes I can see that APS-C vs FF advance in the result for the A77 vs the A900, colour depth is similar, dynamic range is similar too, but one has to marvel at how it managed to garnish an overall score about the same when it has a usable low light high ISO rating so low by comparison. http://www.dxomark.com/index.php/Cameras/Compare-Camera-Sensors/Compare-cameras-side-by-side/(appareil1)/834%7C0/(brand)/Nikon/(appareil2)/734%7C0/(brand2)/Sony/(appareil3)/371%7C0/(brand3)/Sony
Greg
Ps some money might have changed hands perhaps...


Top
 Profile  
 
 Post subject: Re: Reasons for buying a NEX-VG900 instead of an A99
Unread postPosted: Thu Jan 10, 2013 2:44 pm 
Minister with Portfolio
User avatar

Joined: Tue May 22, 2007 5:38 pm
Posts: 2362
Location: NYC
David Kilpatrick wrote:
Truth is I'm working on an article as one of a team of three writers for a 50 best products of 2012 guide, and the NEX-VG900 specs had to be investigated. I'm very impressed that it shoots raw, that's all. I do not plan to buy one.

Apparently, your friend Paul Genge did plan to buy a NEX-VG900, but on his review of the camera he seams quite disappointed
http://www.youtube.com/watch?v=znMWmOeGHp0

_________________
Pako
------------
http://www.phototeka.net/qosqo.php


Top
 Profile  
 
 Post subject: Re: Reasons for buying a NEX-VG900 instead of an A99
Unread postPosted: Sat Jan 12, 2013 10:22 pm 
Subsuming Vortex of Brilliance
User avatar

Joined: Fri Sep 26, 2008 10:48 pm
Posts: 3273
Most of the complaints seem to be based on handling and button location etc.
Quite a good video overall, nice to see he can now speak his mind freely as he's no longer working for Sony


Top
 Profile  
 
Display posts from previous:  Sort by  
Post a new topicPost a reply Page 2 of 2   [ 23 posts ]
Go to page Previous  1, 2


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:  
cron


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