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06-07-2015, 06:13 PM   #31
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QuoteOriginally posted by stevebrot Quote
I am not a live view user except for when I am doing focus calibration and even then always use magnified manual focus. Without doing some hands-on research, I cannot comment on the subject beyond the observation that CDAF complaints on this site are relatively rare and the anecdotal accounts from the camera reviewers on this site that the CDAF implementation has superior accuracy and precision compared to the PDAF system. It may be that bright lighting at wide apertures has not been a use case for those people.
It is the K-01 where you have no other option that I would have thought people would have taken notice of. I mean, you can't use AF and shoot at fast apertures with an 'A' lens or newer on a bright day -- at all, it just doesn't work. Seems like that would cover a pretty substantial set of use cases. (Maybe the pancake 40 is immune?) You can't even use manual focus unless you know to use the magnify function. I keep hoping someone will tell me that I'm a dummy and there is some setting that will fix it, but no one ever talks about this even though we get a zillion threads about "why isn't this in focus?" which are always user error. If I get a chance tomorrow and it isn't raining, I'll show you how bad it is...

Oh, and take note of what I said earlier when you are doing your focus calibrations -- the aperture setting will affect how easily the camera will confirm focus, so any AF adjustments should be done with the aperture always kept at wide-open (even if you aren't actually taking shots, which if you are using the "dot-tune" method you might not be because that just involves seeing if you get the green hexagon or not at various adjustments)...

06-07-2015, 06:29 PM   #32
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QuoteOriginally posted by vonBaloney Quote
If I get a chance tomorrow and it isn't raining, I'll show you how bad it is...
Edit:

(stuff that was not pertinent)

End Edit:

While you are doing your tests, I would suggest 10 shots far-near, 10 shots near-far, camera on tripod at same position for all twenty frames, intended focus point on high-contrast target with an FA series prime. Repeat for both bright with lens stopped down by this strange camera feature and same lighting with aperture ring on the wide open setting. Post full-resolution center crops best and worst of each series at point of focus. 40 exposures total. At least, that is how I would do it.


Steve

Last edited by stevebrot; 06-07-2015 at 06:47 PM.
06-07-2015, 06:53 PM   #33
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QuoteOriginally posted by vonBaloney Quote
Oh, and take note of what I said earlier when you are doing your focus calibrations
To be honest, I have only applied focus fine adjustments to two of my lenses, both of which using magnified live view as the standard. The shimming of my Katz Eye was done similarly. With those two exceptions, I have found that the factory default works quite well with most of my AF lenses and that AF results agree closely with the split image in the viewfinder.

As you may remember, it was that split image that helped confirm the AF system differences that exist when the lens is set wide open vs. at a narrower aperture when that topic was being discussed several months ago.


Steve
06-07-2015, 07:05 PM   #34
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QuoteOriginally posted by stevebrot Quote
DotTune does not use the green hexagon as a standard.
With dottune, you critically focus in live-view, or just make sure you are in critical focus anyway, and then you turn AF off so it doesn't move. Then you go through the adjustments one at a time setting them, from -10 to +10, and then you hit the shutter half-press or AF button to activate the focus confirmation system (even though you are now in manual) and you write down if get that confirmation, i.e. the green hexagon goes on or doesn't or goes on slowly or is flickering. You find the range where it confirms instantly, and then set your final AF adjustment to the mid-point of that. So that's how it uses the green hexagon. (My point being is you might not think of what the aperture is set to during this entire procedure because you aren't actually taking any shots, but where the aperture is set on the dial will affect whether you get that green hexagon or not, and how fast you get it -- if you happen to have it at f/6.3 it will be confirming all over the place, but if you are at say f/2.8, it is much more discerning about when the green hexagon comes on.)

QuoteQuote:
While you are doing your tests, I would suggest 10 shots far-near, 10 shots near-far, camera on tripod at same position for all twenty frames, intended focus point on high-contrast target with an FA series lens. Repeat for both bright with lens stopped down by this strange camera feature and same lighting with aperture ring on the wide open setting. Post full-resolution center crops best and worst of each series at point of focus. 40 exposures total. At least, that is how I would do it.
Send me a fast FA lens and I'll do that. I have to think about what I have right now that is suitable. I no longer have some of the lenses I've had pass through my hands that showed the problem. The Sigma 70/2.8 macro will show it, but it doesn't have an aperture ring to force it open. I do have the Sigma 100-300/4 which I haven't tried -- that is only a stop off so we'll see (pretty sure it goes to 5.6 when it stops down but not positive) I'm not sure I've ever even tried autofocusing with the aperture not on 'A' -- does that even work?

If I had more (fast) AF lenses, I would have been complaining about this even sooner. I always knew it did that stop down thing, which annoyed me for manual focus, but I figured I'm in an extreme minority manually focusing all the time and only a minority of my lenses even have 'A' settings at all. I thought surely it doesn't do that when it is autofocusing? Cause that would really be stupid, and everyone would be complaining. Then I put a 70-200/2.8 on it (which I no longer have) and couldn't get an in-focus shot and realized what was happening...

06-07-2015, 07:11 PM   #35
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While I can see how this other issue - auto-partial-closure of the lens iris in liveview under bright conditions - would be annoying and might cause inaccurate focusing with fast lenses, it is quite different from the problem I (the OP) brought up. If you wish to discuss/debate this issue at length, perhaps a new/different thread might make a more appropriate venue? I don't mean to sound annoying, but going off-topic will discourage others who might want to discuss the original problem...
06-07-2015, 07:19 PM   #36
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QuoteOriginally posted by Doundounba Quote
While I can see how this other issue - auto-partial-closure of the lens iris in liveview under bright conditions - would be annoying and might cause inaccurate focusing with fast lenses, it is quite different from the problem I (the OP) brought up. If you wish to discuss/debate this issue at length, perhaps a new/different thread might make a more appropriate venue? I don't mean to sound annoying, but going off-topic will discourage others who might want to discuss the original problem...
Apologies, of course. I only brought it up because apparently there have been changes in the recent model since your problem is new to you with the K-3 and so was just wondering if they had done anything about that other annoying problem. It does sound like the engineers need to sit down and work out a philosophy of just how live view is supposed to work under different circumstances, and maybe provide some options to have it work this way or that at the photographer's preference especially since we've seen complaints on both sides of this issue. It should have a toggle -- maintain average brightness for viewability OR act as a shot preview (more or less) of the current settings.
06-07-2015, 08:24 PM   #37
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QuoteOriginally posted by Doundounba Quote
While I can see how this other issue - auto-partial-closure of the lens iris in liveview under bright conditions - would be annoying and might cause inaccurate focusing with fast lenses, it is quite different from the problem I (the OP) brought up. If you wish to discuss/debate this issue at length, perhaps a new/different thread might make a more appropriate venue? I don't mean to sound annoying, but going off-topic will discourage others who might want to discuss the original problem...
Sorry. The thread took on a dual tone early on due to my mentioning the second behavior. I am also sorry that there is no apparent answer to your problem. The dimming is a consistent and predictable behavior with an apparent purpose and no means to shut it off. There is no way that I could find to control both shutter speed and aperture from the body in live view without the display dimming or brightening to match the degree of under/over exposure. The only solution I might offer is to shoot with a manual aperture lens or switching to the optical viewfinder.


Steve
06-07-2015, 09:44 PM   #38
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How about if you crank up the EV compensation? (Which in M mode won't change your settings, just the metering.) I think that affects screen brightness, doesn't it?

Another option for macro is to maybe use an always on LED light panel to keep the scene lit. (Are there any of those that will actually turn OFF when you fire it so the flash is the light source for the shot?)

06-07-2015, 11:54 PM   #39
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QuoteOriginally posted by vonBaloney Quote
The point is that the camera stops down while you are focusing (or just viewing) and so it is achieving focus or confirming focus (if manual) with possibly a greater depth of field than you will actually shoot at. So if you take your 1.4 AF lens, set it to 1.4, and go use CDAF autofocus *in bright sunlight*, the camera will be autofocusing at f/5.6, then you take the shot at f/1.4 and whatever you focused on is very very likely BADLY out of focus (because in order to achieve critical focus at f/1.4, the aperture actually needs to be wide-open while you do so, and it is not). I think you will find it is nearly impossible to get in-focus shots (of what you want) with a fast lens using a fast aperture when using CDAF liveview AF (or even MF if you aren't using the zoom function). And I find it strange that I seem to be the only one to have ever noticed this...
You're the only one because that isn't how it works on a properly functioning K-01 with current firmware. I noticed this years ago because the K-30 in live view defaults to f/4 even in low light - as a sensor preservation measure, but overkill because you don't need that in low light. This is easily overcome by using the optical preview dedication - and opening the aperture to the desired setting. Even back then when I did that test, the K-01 always stayed open on the fast lenses in relatively low light. In brighter light, the K-01 will stop down to preserve the sensor. The K-3 works the exact same way (in live view only, of course).

I tested three lenses, including an MF with A setting, a new AF with no physical aperture ring, and an AF with A setting - all staying wide open as that's how the K-01 is supposed to function in all but very bright light. If they do stop down, I would use the Red button to dedicate optical preview, and that would overcome the focus problem by opening the aperture if desired. I don't see it as much of an issue if you remember the work around. Then again, most often you are not going to be using wide open apertures in bright light, right?

Last edited by ScooterMaxi Jim; 06-08-2015 at 12:04 AM. Reason: further information to clarify
06-08-2015, 05:21 AM   #40
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QuoteOriginally posted by vonBaloney Quote
How about if you crank up the EV compensation? (Which in M mode won't change your settings, just the metering.) I think that affects screen brightness, doesn't it?
Doesn't do anything for me... Does that work for you?

BTW, I absolutely wouldn't mind a fix that only works when (manual) flash is used, but I haven't found one. I tried to shoot with the onboard flash rather than an external manual flash - I used either "Flash On" or "Manual Flash Discharge" modes - and it didn't change anything either. You'd think that when using the onboard flash, the camera would at least be aware that the flash is going to fire (plus possible optical slaves), and not think that it's evaluation of how the scene is exposed without flash has anything to do with how the final exposure will look, but nope, no dice, still dimming the display as I close the aperture.

QuoteQuote:
Another option for macro is to maybe use an always on LED light panel to keep the scene lit.
Yes, this is another possibility, but adds even more equipment and weight. On the other hand it would also be useful when shooting reversed lenses... Or, I could go back to the K-01, I guess, but then I lose the 24mp sensor with no AA... The least inconvenient right now is to use the aperture ring, and hope for/dream of a FW bug fix...
06-08-2015, 06:16 AM   #41
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QuoteOriginally posted by Doundounba Quote
The least inconvenient right now is to use the aperture ring, and hope for/dream of a FW bug fix...

One other thing that you might(?) contemplate to try is to press the AE-L button before you stop down.


That way, your Liveview image will remain at constant brightness as long as you don't change the scene / ligthening conditions, although you will get longer exposure times than synchrononization speed. Whitin limits, this could perhaps be an acceptable work-around when you use flash?
06-08-2015, 08:07 AM   #42
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QuoteOriginally posted by ScooterMaxi Jim Quote
You're the only one because that isn't how it works on a properly functioning K-01 with current firmware. I noticed this years ago because the K-30 in live view defaults to f/4 even in low light - as a sensor preservation measure, but overkill because you don't need that in low light. This is easily overcome by using the optical preview dedication - and opening the aperture to the desired setting. Even back then when I did that test, the K-01 always stayed open on the fast lenses in relatively low light. In brighter light, the K-01 will stop down to preserve the sensor. The K-3 works the exact same way (in live view only, of course).

I tested three lenses, including an MF with A setting, a new AF with no physical aperture ring, and an AF with A setting - all staying wide open as that's how the K-01 is supposed to function in all but very bright light. If they do stop down, I would use the Red button to dedicate optical preview, and that would overcome the focus problem by opening the aperture if desired. I don't see it as much of an issue if you remember the work around. Then again, most often you are not going to be using wide open apertures in bright light, right?
I will continue this discussion in a new thread after I've done a little testing...
06-08-2015, 09:29 AM   #43
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QuoteOriginally posted by Doundounba Quote
Doesn't do anything for me... Does that work for you?
I only have the K-5 to test -- changing the aperture does nothing at all to the display (as you know). However, changing the EV comp will in-fact darken or brighten the screen as you do so. Looks like the effect is restricted to the -2 to +2 range. Anything more extreme (it goes to -/+ 5) doesn't do anything.
06-08-2015, 10:02 AM   #44
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QuoteOriginally posted by Doundounba Quote
Doesn't do anything for me... Does that work for you?
It did not work for me either.


Steve
06-08-2015, 10:06 AM   #45
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QuoteOriginally posted by Doundounba Quote
and hope for/dream of a FW bug fix...


ROFL!

Sorry, not meaning to be disrespectful. It would be nice, but such is probably not even on the JIRA feature list for the K-3 firmware team, much less with any priority.


Steve
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