a55 EVF questions

[Greg Beetham]

The A55 EVF will be fine for fast jets, stevecim, just ask mike2008, or, if it turns out it isn't quite up to scratch you can always buy the new improved model as well, due out sometime this year.
Greg

[stevecim]

The A55 EVF will be fine for fast jets, stevecim, just ask mike2008, or, if it turns out it isn't quite up to scratch you can always buy the new improved model as well, due out sometime this year.
Greg

come on Greg, no need to add more wood to that fire It was a serious question, because at the time I found the EVF on the FZ10 was hopeless but the EVF on my Pana camcorder worked fine. So clearly at that time there was a difference between EVFs on Pana camcorders and still cameras maybe do to differences in how data was read from the sensors? .

To be honest I have yet to see any photos that show the A33/55 produce any more "errors" in images then lenses already produce in any other DSLR, it seems that objects that produce ghosting on A33/55 also could produce "errors" in any other camera, i.e bright pin points off lights in very dark scenes .
for 99.99% of users I sure they would produce great photos (have not seen much macro work but have not spent a lot of time looking for it) ( DPR said ghosting was a non-issue then it must really be a no issues since they make big issues out of the smallest problem in Sony cameras ).

DK has pointed out some scenarios where the EVF does fail. I would like to know how it preforms in sports , extreme sports, macro (studio and field),

[Neonsquare]

Any guess on the EVF delay is just that: A guess. My own guess is, that it is below human reaction time, which would be somewhere around 1/10s. Anyone seeing an EVF(!) delay of 1/2 second can never have hold a SLT in his hands. There is a TTL--Flash related shutter delay of 3/10s - 1/2s but not an EVF delay like this. The theoretical minimum according to current SLT EVF tech would be 1/60s, because thats the refresh of the EVF unit.

Future improvements of Sonys EVF have to be mainly in four kinds:
1) Higher possible refresh time
Combined with very high FPS from the signal processing unit. I want to have 150-200hz here.
2) Higher Resolution
3) Higher Dynamic contrast
4) Less EVF delay (significantly less than 1/10s)

That are the facets, which have to be improved to make an EVF be a valid replacement for an OVF. In it's current implementation 1,2 and 4 are very usable in many situations, making the camera a practical tool. Drawbacks in detail resolution can be often remedied by magnification. EVF delay already is low enough to be more of a theoretical problem and EVF refresh is just a little bit above being no showstopper for me. The whole package is - to me - better than any small OVF of the past. It is partially better and worse to the A700 OVF and it has some tricks even the superb A900 OVF cannot do. For APS-C the EVF already replaced the OVF to me; for FF not.

[stevecim]

One thing to keep in mind, with all this talk of ms for this and ms for that, is that the EVF is not a direct feed from the image sensor, it's a processed signal, it's resolution gets changed , other elements are added to the display data before its presented to the EVF ( this take some time, it might be micro-secs but it all adds up) . There is a very good chance that the refresh rate will change depending on how many pixels need updating from frame to frame. So even if Sony do state the refresh rate, like most things involving computers, it's stated refresh rate will be best case conditions, i.e A blank white wall with all other display information turned off.

Unless someone has connected a "CRO" to the EVF and measured the refresh rate under many different conditions, any talk of ms is just pure guess work.
I don't have a A33/55 but I can say the QLV on the A350/550 is no where near 30fps.

[stevecim]

There is a simple test, point the camera at a object , move the camera left to right, how fast can you move the camera before the image starts to break up.
with the A550, via the OVF the image never breaks ups, with the QLV, I doubt the video stream is even 10 fps , the way the images breaks up with anything but the slowest movement

[Argonaut]

Any guess on the EVF delay is just that: A guess. My own guess is, that it is below human reaction time, which would be somewhere around 1/10s.

Hey, it's almost as if you read my post on 3/7! But seriously, there is a way. First, go to
http://www.humanbenchmark.com/tests/rea ... /index.php
and measure your reaction time. Then go to
http://www.online-stopwatch.com/full-screen-stopwatch/
and take a photo of the screen viewed through the EVF. To duplicate the mouse click action in test #1, use manual focus and do NOT anticipate the moment when you take the photo - wait for your target number to appear and THEN push the button. The difference between the elapsed time of the first test and the second will be the delay caused by the EVF.

My numbers? Reaction time .254 seconds average (YMMV - I'm on Medicare); between .05 and .15 seconds added EVF delay with vast majority falling in the .1 second area.

[agorabasta]

The EVF fps is no guess at all. It's exactly 50Hz, just exactly the same as is the video framerate with my a55. It should be 60Hz with an Americas' version.
That's very easy to check - look at some LCD display through the EVF; if the fps is the same, there's no beat flicker.

The exposure+processing delay must be not more than one frame period. There's absolutely no need to keep more than one frame in the pipeline, and the processing is the essentially negligible some microseconds. So the delay before feed into the EVF display is just the exposure/readout time.
Now that is some real problem since that exposure happens with the lens wide open, and hence may fall too short in bright light. Then you'd see a sequence of momentary positions of a fast moving object instead of smooth motion. The solution is very straightforward - increase the readout speed to about 200Hz and keep the min ISO of the sensor as low as possible.

[stevecim]

Thanks Agorabasta, your right, had a play for 20 odd minutes with a a55 , live view via the read LCD is way better than QLV on the A350/550. I did notice, via the EVF, that a slight "blue" or "red" shadow would appear around moving objects depending on the direction of movement across the screen, more noticeable on light coloured objects moving across dark background, which gave a slight "stop start" feel. But you really had to look for the fault too see it.

For me, I would be happy with a SLT solution in a A550 size body (provided it worked OK with real fast objects ). I just don't like the feel of the smaller body in my hands.

[bakubo]

For me, I would be happy with a SLT solution in a A550 size body (provided it worked OK with real fast objects ). I just don't like the feel of the smaller body in my hands.

The A77 will likely be larger than the A55 so just wait awhile longer.

[ozziekol]

Mark , I have an A55 and enjoy using it very much. I am not a professional photographer, but I take my photography seriously, as do many other non-professionals. My experience with the EVF for manual focusing has been excellent, particularly as the viewfinder has a detail enlarging feature allowing very accurate manual focussing especially when used with a steadying device ( tripod etc.) I have read many technical discussions on the merits or demerits of the EVF, but in practice I've had no real problems with it even wearing glasses. It handles everything from macro shots to fast moving action.

[bakubo]

Mark , I have an A55 and enjoy using it very much. I am not a professional photographer, but I take my photography seriously, as do many other non-professionals. My experience with the EVF for manual focusing has been excellent, particularly as the viewfinder has a detail enlarging feature allowing very accurate manual focussing especially when used with a steadying device ( tripod etc.) I have read many technical discussions on the merits or demerits of the EVF, but in practice I've had no real problems with it even wearing glasses. It handles everything from macro shots to fast moving action.

In 2002 I bought a Minolta D7i that had an EVF, albeit not as good as the one in the A55. The single best thing about the EVF was being able to zoom in with one button push and very precisely MF.

By the way, it is amusing on dpreview to see people on the Sony DSLR forum arguing about whether an EVF is better than an OVF and seeing how some of the EVF supporters are cheering the demise of the OVF. Then go over to the Sony NEX forum and they argue about the EVF vs. the rear LCD. There are some very vocal people there who claim the rear LCD is better than an EVF and cheer that Sony doesn't have an accessory EVF for the NEX and hope there never is one. So, it looks like people who like an OVF and people who like an EVF are both Luddites. It is only the rear LCD in the future, I suppose.

[Dusty]

So, it looks like people who like an OVF and people who like an EVF are both Luddites. It is only the rear LCD in the future, I suppose.

I certainly hope NOT!

Dusty