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09-11-2015, 12:07 PM   #16
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i have a k-30 and a k-s2. try it with a da 35mm da f/2.4 you'll definitely see it stop down during liveview.

09-11-2015, 12:53 PM   #17
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As I am 90% a landscape photographer, i tend to set my f stop between f6 to f14 depending on my foreground so I haven't seen the problem, but i will surely try that out with my FA 35 f2 and see what happens
09-11-2015, 12:58 PM   #18
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QuoteOriginally posted by AtitG Quote
i have a k-30 and a k-s2. try it with a da 35mm da f/2.4 you'll definitely see it stop down during liveview.
OK - I just tried this with my K3 and K50. What I found was interesting. It appears that the lens is stopped down to f/4 during LiveView. This seems fairly consistent. I tried it on the DA 40 Limited and the DA 18-135. In both cases I set the camera to Manual mode and set the shutter to 1 second or so to be able to see it. I fired it off without live view wide open and then went to live view and saw that as soon as I engaged it the iris on both lenses stopped down slightly. The aperture setting on the camera has no impact on this btw. It isn't easy to see on the 18-135 - particularly since if I zoom past the point where f/4 is smaller than the maximum aperture it no longer happens because it is no longer needed.

My guess would be that the CDAF focus system is better at f/4 or they want to avoid prolonged sensor exposure at > f/4 openings. In any case it is true and only applies when the maximum aperture is not already f/4 or slower.
09-13-2015, 02:37 PM   #19
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QuoteOriginally posted by AtitG Quote
my problem with dslr liveview is that the aperture is stopped down during liveview
This may indeed be a problem. The body may partially stop the lens down in bright conditions, though it depends on the lens mounted (maximum aperture and whether the lens supports aperture control from the body). It is definitely something to be aware of particularly when using magnified live view for fine focus (not a huge issue with landscape work).


Steve

09-13-2015, 02:40 PM   #20
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QuoteOriginally posted by stevebrot Quote
This may indeed be a problem. The body may partially stop the lens down in bright conditions, though it depends on the lens mounted (maximum aperture and whether the lens supports aperture control from the body). It is definitely something to be aware of particularly when using magnified live view for fine focus (not a huge issue with landscape work).


Steve
My tests were in a very poorly lighted room just in case you were wondering. But pointing the lens outside did not change the amount it stopped down.
09-15-2015, 12:10 AM   #21
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QuoteOriginally posted by UncleVanya Quote
My guess would be that the CDAF focus system is better at f/4 or they want to avoid prolonged sensor exposure at > f/4 openings. In any case it is true and only applies when the maximum aperture is not already f/4 or slower.
I've seen my camera closing and opening aperture (during live view) in bright daylight, based on the scene in front of it. didn't give much attention to find out what aperture is it using. and that was with FA50/1.4, but CDAF focusing was still accurate(photos shot @f/1.4 or f/2 where PDAF isn't), despite aperture being closed down during live view.
09-15-2015, 06:52 AM   #22
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QuoteOriginally posted by mtux Quote
I've seen my camera closing and opening aperture (during live view) in bright daylight, based on the scene in front of it. didn't give much attention to find out what aperture is it using. and that was with FA50/1.4, but CDAF focusing was still accurate(photos shot @f/1.4 or f/2 where PDAF isn't), despite aperture being closed down during live view.
Try playing around with it and see if you get consistently the same amount of stopping down without respect to light levels - so far that's what I am seeing. Also I was never able to see anything other than f/4 (or slower wide if the lens was slower wide open).
09-15-2015, 06:47 PM   #23
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QuoteOriginally posted by UncleVanya Quote
Try playing around with it and see if you get consistently the same amount of stopping down without respect to light levels - so far that's what I am seeing. Also I was never able to see anything other than f/4 (or slower wide if the lens was slower wide open).
Nope, it's not a constant thing. I just tried it with DA35ltd, DA18-135 and FA50/1.4 on K-3
It does change the aperture during live view depending on scene in front of it. Pointing all lenses to outside the house (A hazy overcast bright day) K-3 closes all lenses to f/11! even DA18-135 zoomed all the way to 135mm which is an f/5.6 lens. and pointing the camera to other areas it changes to f/8, f/4, wide open, ...

09-15-2015, 07:47 PM   #24
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QuoteOriginally posted by mtux Quote
Nope, it's not a constant thing. I just tried it with DA35ltd, DA18-135 and FA50/1.4 on K-3
It does change the aperture during live view depending on scene in front of it. Pointing all lenses to outside the house (A hazy overcast bright day) K-3 closes all lenses to f/11! even DA18-135 zoomed all the way to 135mm which is an f/5.6 lens. and pointing the camera to other areas it changes to f/8, f/4, wide open, ...
isn't the 18-135 @ 135, f/5.6 wide open? This is interesting. What ISO were you set to? I haven't seen this yet. Too dark here to play with it much but I can try tomorrow. That is very disturbing.
09-16-2015, 05:45 AM   #25
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I had the same experience as UncleVanya, the aperture doesn't change in liveview even if i put a flashlight in front of the lens. I tried this on a K-30.
09-16-2015, 05:49 AM   #26
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QuoteOriginally posted by mtux Quote
Nope, it's not a constant thing. I just tried it with DA35ltd, DA18-135 and FA50/1.4 on K-3
It does change the aperture during live view depending on scene in front of it. Pointing all lenses to outside the house (A hazy overcast bright day) K-3 closes all lenses to f/11! even DA18-135 zoomed all the way to 135mm which is an f/5.6 lens. and pointing the camera to other areas it changes to f/8, f/4, wide open, ...
K3 - which firmware and what exposure settings? (Mode, shutter, f/stop)

This is interesting.
09-16-2015, 07:12 AM   #27
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QuoteOriginally posted by UncleVanya Quote
isn't the 18-135 @ 135, f/5.6 wide open? This is interesting. What ISO were you set to? I haven't seen this yet. Too dark here to play with it much but I can try tomorrow. That is very disturbing.
Well, it was on TAv mode, but I'm sure I have the same experience on Av too.
shutter speed was 4sec (so I can press the shutter and see how close it will be in that aperture) aperture was changing from wide open to f/11
I don't think these can have anything to do with it. but if you insist, I'll try it again tomorrow with any setting you want.
09-16-2015, 07:21 AM   #28
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QuoteOriginally posted by mtux Quote
Well, it was on TAv mode, but I'm sure I have the same experience on Av too.
shutter speed was 4sec (so I can press the shutter and see how close it will be in that aperture) aperture was changing from wide open to f/11
I don't think these can have anything to do with it. but if you insist, I'll try it again tomorrow with any setting you want.
Just trying to get a handle on what we might be doing different. I too used a long shutter speed - and I don't think I noticed what ISO I had set. I used Manual mode I think to force it to my shutter speed and aperture (wide open).
09-16-2015, 08:41 AM   #29
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I use live view for macro, anything requiring manual focusing, and composition when shooting overhead or using the self-timer and including myself in a picture. For landscapes I almost always use the viewfinder.
09-16-2015, 02:15 PM   #30
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Well, I suspect that with Liveview, the camera is essentially taking a picture (continually) and showing it on your screen. And, it has to expose it correctly, probably using some type of Shutter Priority mode (depending perhaps on what refresh rate they are going for and what "processing" is needed).

Thus, it doesn't surprise me that the camera would behave differently than what we get through the optical viewfinder.

As for using Live View, I've never thought of it. I wish I would have in some cases. It would be convenient on a tripod, although I'm a bit lazy and don't use a tripod very much unless the light is lower. I kind of wish I did, although I'm a bit conscious of point of view too and worry that too many of my shots would end up from a perspective that is always about 5.5 feet (170 cm) above the ground surface. I know that I could adjust the tripod, and I even know that my compositions would probably be a bit better.

But, even for landscapes, I like being able to lower my whole self to a lower position (ground level) and quickly adjust composition to get more varied compositions quickly. And all that resolution with the K-3 (and even the K-5 when that was my primary camera) allowed me a lot of room to compose wider than I anticipated for the final, and then crop afterward.

Still, Live View is worth keeping in mind. My own landscapes like to favor a foreground item to provide depth to a scene, and despite the theoretical depth of field at apertures like f8 to f16 (which is the limit of what I would go), I still try to nail focus on a foreground object that I think is important. It isn't like focus is tack sharp through the whole depth of field anyway, so I like the foreground objects to be and seem sharper than the background of my landscape that might not matter so much. Ultimately, personal preference. Sometimes the background is most important.
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