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PaulE
30th May 2010, 10:04 AM
Last night I came across a post on a different forum (DPReview) which claimed that AF speed - or more acurately the delay before AF starts can be improved on significantly by doing no more than turning of the LCD whilst shooting. TBH I was a bit sceptical so I tried it to see what the fuss was about and the results are pretty surprising....

Whilst continuously half pressing the shutter with the screen on there appears to be around a 1/2 second delay before the AF kicks then almost immediately AF is achieved (with the pro grade lenses anyway) and the camera beeps, half press again and the 1/2second or so delay occurs again before you get another AF lock + beep.

Now switch the LCD off whilst doing the same - the delay before the AF kicks in dissapears and AF lock + accompanying beep is significantly quicker in coming, half press again and the beep is near instant. That 1/2 second or so delay is now gone :eek:

According to the OP on that forum the Olympus firmware by default gathers the required information needed to update the LCD before it starts the AF cycle but with the screen turned off a whole chunk of the firmware, relating to the LCD, is skipped speeding up the camera quite considerably.

Maybe in the real world such an improvment might not actually be that useful but none the less my LCD will be off for a while to see if it is noticeable. I've not tested it yet but I have to wonder if CAF is affected too - and if so removing that 1/2 a second or so delay could make a massive difference for fast moving objects like BIF shots etc...

From what I've read the peculiarity exists in all E-system SLRs including the E3 but not sure about the micro four thirds cameras. Also Panny cameras are unaffected too - which might well explain why some people have the opinion the AF was quicker on those SLRs?

Anyway, my apologies if you have come across this before and know all about it but it was a new one on me and thought it might well be to the vast majority here too...
Paul.

Radar
30th May 2010, 10:16 AM
Thanks for the tip! I'll try this as the AF speed sometimes annoy me.

Ross the fiddler
30th May 2010, 11:43 AM
Whilst continuously half pressing the shutter with the screen on there appears to be around a 1/2 second delay before the AF kicks then almost immediately AF is achieved (with the pro grade lenses anyway) and the camera beeps, half press again and the 1/2second or so delay occurs again before you get another AF lock + beep.

Now switch the LCD off whilst doing the same - the delay before the AF kicks in dissapears and AF lock + accompanying beep is significantly quicker in coming, half press again and the beep is near instant. That 1/2 second or so delay is now gone


Thanks. I've just tried it on my E30 & for the sake of not refocusing, I pointed it at the TV seeing it was bright enough not to bring low light into it, & with the display on, there is that small delay, but with it off, there is no delay. As there is a top display, it is not necessary to have the main one on all the time & think of the battery power you are saving. The main display still shows the photo afterwards, depending on that setting in the menu.

The display needs to be off for evening shots anyhow as the glare from it makes seeing through the view finder a little difficult.

Thanks again. It's nice to learn something new every day.

Ross

Macca
30th May 2010, 12:00 PM
I reckon he could be right.
When I used the E410 my brother in law also had one. I always had the LCD and the picture review set to off in order to save battery more than anything else. After a couple of days out together shooting bikes he moaned about his lack of focus compared to mine when shooting CF. After several more moans we swapped cameras for an afternoon and his improved while mine worsened. Before assuming his camera was faulty we went through all menus setting his camera identical to mine. After that we were pretty much on par CF wise.
So, it could have been the LCD setting. Can't be sure as so many things were changed in one swoop.

Ross the fiddler
31st May 2010, 12:15 AM
I have just tried this on my E520 & with the display on, as you look through the view finder, the display shines in your face & eye but when the shutter button is pressed (half or full) the display will blank out. Obviously there is a short delay before focusing & metering can occur as it has to be after there is no more light reflected from your face/eye. There is no delay with the display off. For metering purposes, there is a supplied view finder cover. It is there for live &/or long exposures so the exposure meter is not affected by light coming in through same. Therefore it is equally important for the display to be off to stop that reflected light affecting the meter reading. For Olympus to be a fast response camera & still have that supercontrol panel dislpayed before shooting, it should have an eye/face detector on its camera to blank the display earlier to eliminate that delay. Other cameras do have this & the pro models have the sensor to control a shutter for the view finder (as well?). I don't believe the delay has anything to do with gathering information, just to kill the reflected light before activating the exposure meter.

I will be pressing that info button after checking the settings to blank the display for that instant response time.

Thanks again for highlighting this helpful little hint.

Ross

PaulE
31st May 2010, 09:56 AM
It's a possibility but I'm not so sure... I spent a few minutes yesterday messing with the E510 + 50-200mm and the the same effect seems to occur in C-AF - swinging through a building for example whilst half pressing the shutter button gets you much more closely spaced AF locks / confirmation beeps with the LCD off than is possible with the LCD on and in C-AF mode the screen is blacked out the whole time that you have the shutter half pressed - so the camera would have no reason to want to pause briefly to black the LCD between shots since it's already blacked out?.

Whatever the reason I see it something that Olympus could definately work on in their next SLR (if there's going to be one). If it is a firmware thing then it's an easy fix, if it's a reflected light thing then they should be giving people the choice whether they want to risk light reflecting ino the viewfinder by allowing the LCD to remain on when taking photos (which may be impossible with current processing power) - hence avoiding the delay in having to black it out before starting AF afterall this would only a problem with very long low light exposures where the photographer has his eye away from the viewfinder - which by definition means AF speed isn't critical. Sports photgraphers on the other hand aren't going to care if a insignificant amount of light somehow managed to squeeze though the gap between eye and viewfinder as it simply isn't going to effect the exposure to any noticable degree in good light / high shutter speed exposures and I'd bet my last rollo that every such photographer would risk just such a scenario for a more responsive AF system?

forester
31st May 2010, 11:10 AM
That is one of the best tips I have read, thanks very much, I really had not thought of that one, I must be getting old.*yes
Just tried it with bird flight, magic.:)
The info I want it is the view finder anyway, but one press off the button to read the LCD does it so this will be switched off from now on.
*chr
Richard

RAC
2nd June 2010, 12:06 PM
Hiya,

I came across the same post as you, and on reading it I've the same reaction as when reading this post - why is the screen ON in the first place? It's an SLR, with an optical viewfinder - why waste battery power with something useless? Just turn the screen on when it's actually needed, ie liveview, or the *occasional* review of histograms!

RAC

PaulE
2nd June 2010, 01:27 PM
Hiya,

I came across the same post as you, and on reading it I've the same reaction as when reading this post - why is the screen ON in the first place? It's an SLR, with an optical viewfinder - why waste battery power with something useless? Just turn the screen on when it's actually needed, ie liveview, or the *occasional* review of histograms!

RAC

I look at it and think why should you have to turn the LCD off to get maximum AF performance out of an DSLR???. The super control panel on the LCD is tremendously useful, god only knows why you'd find it useless. I accept that on the E3 + E30 it is of less importance due to the top lcd panel and placement of the settings within the viewfinder itself but with the E410 / E510 in particular the settings are not exactly in the most useful place - to the right hand side of the viewfinder and it's mostly quicker and easier to take a breif glance at the LCD to see every important setting in one go.

Ross the fiddler
2nd June 2010, 10:31 PM
I look at it and think why should you have to turn the LCD off to get maximum AF performance out of an DSLR???. The super control panel on the LCD is tremendously useful, god only knows why you'd find it useless. I accept that on the E3 + E30 it is of less importance due to the top lcd panel and placement of the settings within the viewfinder itself but with the E410 / E510 in particular the settings are not exactly in the most useful place - to the right hand side of the viewfinder and it's mostly quicker and easier to take a breif glance at the LCD to see every important setting in one go.

Yes, I totally agree with you, having had an E410 & have E520 & E30. That's why I think a sensor near the viewfinder could be used to blank the screen to save on that small delay when pressing the shutter button. They are used on new ultra zoom P&S cameras (for switching between screen & viewer), so why not Oly DSLR's too to make the camera even more responsive.

In the mean time, if you want to capture that fleeting moment without any delay, check the settings in the supercontrol screen, then press INFO (to turn off the display) for that immediate focus response.

Ross