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01-06-2013, 08:18 AM   #16
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QuoteOriginally posted by zosxavius Quote
Why not just shoot in manual? :-)
Metering is unreliable at the limits. Also the camera is probably trying to keep shutter speeds at a manageable level. Meter in live view and see what that comes up with..
Yes, thanks that's a thought - I do realize I am pushing the boundaries and as you say the metering may be unreliable past the limits -
BUT I had just determined it is not quite past the specs - my copy of the K-5 appears to not to be able to reach the lowest limit of LV0 - it get about LV1 to 1.3 - that's over a whole stop difference
- kind of like buying ISO1600 film and finding out it is only ISO800.

Anyway, I do take your point - the reason why I use P mode is probably just due to habit - as I said I have shot this dark jazz club almost on a weekly basis for the past 3 years, and on the K-x I shoot P mode, since I shoot from stage with reasonable light, to off stage - where mostly it is "unreasonable" light.

I bought the K-5 with the expectation that it'd behave in a similar, if not superior, way to the older and lower (entry) level K-x -
it did behave better in lots of ways - but perhaps the most important aspect - the exposure - it did not - the K-x appears for now to work better.

There is now also a very significant input from Ex Finn (posts #6 & #12 linked above) as he managed to get 1/4 sec f/3.5 ISO5000 (with 18-55 kit zoom lens, covered/cap on) same firmware (1.13.23.25)
- so why the difference? Pentax K-5 is a precision instrument, but a variation of over 1 stop, not meeting the specs?
I am just trying to determine if there is something I am not aware of, since the K-5 is brand new (to me) - so that I can reach the same in spec lowest metering limit that Ex Finn managed to reach.

I have already determined a workaround - just use the exposure compensation and dial in +1 stop when shooting at the lowest light limit - since that is already in my "workflow" of changing the exposure compensation to suit the scene - this is easily workable for me.

QuoteOriginally posted by zosxavius Quote
Also just use 6400. It usable for anything but poster sized.
Thanks so much for that input - again it's perhaps habit - on the K-x I shot at ISO5000 max with AutoISO, and not only that, at 10Mp -
so that's why for now I shoot the same settings on the K-5 -
so far the results do look slightly better - except the lowest light shots - the last two dark shots with EXIF and metering segments in the opening post -
but then they were underexposed by about -1 stop (due to my K-5 not being able to meter to the lowest spec'd limit) - so it is hard to compare to my K-x results.

Thanks for the suggestion -
I continue welcome any suggestions on how to get my brand new K-5 to meter down to the same level as Ex Finn managed (in posts #6 & #12 linked above) .

Any other K-5 owners care to please just meter with the lens cap on with the18-55 kit zoom set at 18mm widest setting - @ ISO5000 (with 0 stop exp compensation), please let us know? - only takes a few seconds

Thanks for all the input.

01-06-2013, 08:27 AM   #17
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K-30
18 - 135 lens at 18mm
f 3.5
ISO 5000
P mode
Multi-segment metering
Thumb over viewfinder, cap on lens
Exposure time is 1/10 sec.
01-06-2013, 08:34 AM   #18
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One more thought.... what's the relevance of the "cap on" test since the LV has to be under the low limit anyway?
01-06-2013, 09:02 AM   #19
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QuoteOriginally posted by IchabodCrane Quote
K-30
18 - 135 lens at 18mm
f 3.5
ISO 5000
P mode
Multi-segment metering
Thumb over viewfinder, cap on lens
Exposure time is 1/10 sec.
Thank you, thank you much appreciated. So the newer K-30 seems to only manage 1/10sec that's about LV1.3 - I am not too concerned now perhaps there is the "trend" by Pentax not to set exposure as low as LV0 even though the meter can reach lower?

QuoteOriginally posted by IchabodCrane Quote
One more thought.... what's the relevance of the "cap on" test since the LV has to be under the low limit anyway?
Yes, that is precisely it -
to determine the lowest metering limit one need to get really dark, even zero light condition -
it was much easier just to put the lens cap on (and prevent any light leakage through the viewfinder eye-piece).
Please see my thoughts when I first tried to determine the lowest metering limits on my K-x - Post #132 (linked in the Kx in Use)

Thanks a bunch for your input - very, very useful and somewhat reassuring to me.

01-06-2013, 10:06 AM   #20
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QuoteOriginally posted by UnknownVT Quote
Thank you, thank you much appreciated. So the newer K-30 seems to only manage 1/10sec that's about LV1.3 - I am not too concerned now perhaps there is the "trend" by Pentax not to set exposure as low as LV0 even though the meter can reach lower?



Yes, that is precisely it -
to determine the lowest metering limit one need to get really dark, even zero light condition -
it was much easier just to put the lens cap on (and prevent any light leakage through the viewfinder eye-piece).
Please see my thoughts when I first tried to determine the lowest metering limits on my K-x - Post #132 (linked in the Kx in Use)

Thanks a bunch for your input - very, very useful and somewhat reassuring to me.
Here's a useful link, maybe you've already read it:

What are EV and LV

Converting their definition of EV 0 to F3.5, ISO 5000, I get about 5.5 stops difference in ISO and about 3.5 stops difference in aperture. Call it a net of about two stops. So with an exposure around 1/8 second instead of the expected 1/4 sec at LV 0, I guess it confirms your conclusion that the actual metering is about LV 1 with the cap test (rightly or wrongly).
01-06-2013, 10:28 AM   #21
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I find this odd. My k-5 will meter down to 30" @ iso 80 in Av.. You do the math. Isn't that somewhere around -2 EV? Once shutter speeds get below 1/30 or so, I usually flip to manual and take control. I do a lot of street scene kind of shooting at night, and often -1EV comp is a good idea in Av as the meter wants to over expose to bring up everything to middle grey. For years I shot with a panasonic bridge camera...fz28....fz35...I've gone through a few. They would always consistently meter for the most part (with a tendency to blow highlights, probably since live view is more accurate. In low light I always shot them in manual too. You should try Av at the very least. It should give you ok exposures. When you get to the limits in P, it will do things that you don't expect, like shift aperture in a bracketing sequence and what not. You know you can dial the program line down to use slower shutter speeds right? That might actually help you. Even in P it should easily go past 1/2 second. Are you sure its metering correctly outside and whatnot? I've also noticed that different lenses meter radically differently sometimes requiring compensation in a lot of situations. I'll test with my kit lens later. They say the k-5 will focus down to 0 EV and it will, just not under tungsten.

In low light like this I usually shoot primes and manually focus and pray and refocus on every shot to watch that elusive plane of focus @ 1.4 and lock it. i shot an event last night (until my flash blew up....grrrrrrr) and was using the kit lens because there was no light at all really and I needed the focus assist light. Now I'm rambling....

My advice: Shoot manual or Av. In light like this manual is most useful because you just lock aperture wide open or a click down and then use your shutter speed as your EV compensation. You need glass that can hit f2 for 0EV if you want hand hold able shots. With 6400 you can shoot an empty street at midnight @ f2 with little problems. 3200 makes my slow f4 12-24 usable at night. Inside a dark, dark club, not so much. Even there a fast 50 is going to take some work without some light. If you aren't printing these you could go whole hog to 128,000 and just kill chroma noise in lightroom. Even if you smooth the noise down to nothing and smear all the detail @ 100%, you'd never see it on facebook. 6400 is my limit really, but I have done black and whites at 128,000 that looked better than any film at asa 3200. For handheld you really want to keep your shutter speed over 1/10. I can get sharp 1/4s shots with a lot of bracing and patience, but @ 100% they are still going to be softer than anything a tripod could give me. Once you get over 1/10, sharpness drastically increases on average. For people in a dim room, I'm trying to keep at a min of 1/20 because even then stopping motion is impossible, and everyone's moving. Best of luck. You may also want to certainly try running center weighted metering, You can also lock the meter to the focus point in the menu. That may actually be best because if you are focusing on their faces it will spot meter just the face. Hope some of that helps. Nice pictures btw. I think with some practice you will get along with this setup fine. The AF has to be a big improvement.......
01-06-2013, 12:11 PM   #22
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QuoteOriginally posted by IchabodCrane Quote
What are EV and LV
Converting their definition of EV 0 to F3.5, ISO 5000, I get about 5.5 stops difference in ISO and about 3.5 stops difference in aperture. Call it a net of about two stops. So with an exposure around 1/8 second instead of the expected 1/4 sec at LV 0, I guess it confirms your conclusion that the actual metering is about LV 1 with the cap test (rightly or wrongly).
Thanks so much - yes I have read that page
and I have an olde copy of the once standard reference book the "Focal Encyclopedia of Photography" -

for reference the definitions given on that page:
QuoteQuote:
LV 0 LV Zero is defined as the light level that requires a 1 second exposure at f/1 with ISO/ASA100 speed film.

EV = LV at ISO 100

With ISO/ASA 100 speed film you expose with an Exposure Value (EV) equal to the Light Value (LV).
QuoteOriginally posted by zosxavius Quote
I find this odd. My k-5 will meter down to 30" @ iso 80 in Av.. You do the math. Isn't that somewhere around -2 EV?
Thanks for that, which lens did you use please? - was it the 18-55 kit zoom lens?
I tried Av with the kit 18-55 @ f/3.5 ISO80 and I only got 5sec on my K-5
and same 1/8 sec at ISO5000

QuoteOriginally posted by zosxavius Quote
Once shutter speeds get below 1/30 or so, I usually flip to manual and take control. I do a lot of street scene kind of shooting at night, and often -1EV comp is a good idea in Av as the meter wants to over expose to bring up everything to middle grey. ...
In low light I always shot them in manual too. You should try Av at the very least. It should give you ok exposures. When you get to the limits in P, it will do things that you don't expect, like shift aperture in a bracketing sequence and what not. You know you can dial the program line down to use slower shutter speeds right? That might actually help you. Even in P it should easily go past 1/2 second. Are you sure its metering correctly outside and whatnot? I've also noticed that different lenses meter radically differently sometimes requiring compensation in a lot of situations. I'll test with my kit lens later. They say the k-5 will focus down to 0 EV and it will, just not under tungsten.

In low light like this I usually shoot primes and manually focus and pray and refocus on every shot to watch that elusive plane of focus @ 1.4 and lock it. i shot an event last night (until my flash blew up....grrrrrrr) and was using the kit lens because there was no light at all really and I needed the focus assist light. Now I'm rambling....

My advice: Shoot manual or Av. In light like this manual is most useful because you just lock aperture wide open or a click down and then use your shutter speed as your EV compensation. You need glass that can hit f2 for 0EV if you want hand hold able shots. With 6400 you can shoot an empty street at midnight @ f2 with little problems. 3200 makes my slow f4 12-24 usable at night. Inside a dark, dark club, not so much. Even there a fast 50 is going to take some work without some light. If you aren't printing these you could go whole hog to 128,000 and just kill chroma noise in lightroom. Even if you smooth the noise down to nothing and smear all the detail @ 100%, you'd never see it on facebook. 6400 is my limit really, but I have done black and whites at 128,000 that looked better than any film at asa 3200. For handheld you really want to keep your shutter speed over 1/10. I can get sharp 1/4s shots with a lot of bracing and patience, but @ 100% they are still going to be softer than anything a tripod could give me. Once you get over 1/10, sharpness drastically increases on average. For people in a dim room, I'm trying to keep at a min of 1/20 because even then stopping motion is impossible, and everyone's moving. Best of luck. You may also want to certainly try running center weighted metering, You can also lock the meter to the focus point in the menu. That may actually be best because if you are focusing on their faces it will spot meter just the face. Hope some of that helps. Nice pictures btw. I think with some practice you will get along with this setup fine. The AF has to be a big improvement.......
Thank you for your considered advice.

I have shot this very dark jazz venue for over 3 years on a regular weekly basis with the K-x please see:
Kx in Use ( 1 2 3 ... Last Page) with 373 posts

I seem to do OK with P mode -
I was merely expecting my new K-5 to do similar, if not better than my older and much less K-x -
in many ways my new K-5 does, but in one of the most important areas of low light and limit - it does not seem to.

However since I have heard from two K-5 owners who seemed to manage to meter 1 stop lower than my K-5 - ie: getting 1/4sec @ f/3.5, ISO5000 (0 comp) kit 18-55 at 18mm - compared to my 1/8 sec
I am hoping to find out why the difference?

Thanks
01-07-2013, 11:16 AM   #23
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I was going to suggest shooting manual too. That's what I do in very dark situations that seem to test the limits of the metering system. Works reasonably well IMO. A fast lens helps too and if you don't want to spend a lot on a fast zoom look into a fast 50 or an inexpensive 135. I have a Pentax A 50mm 1.7 and a Sears A 135mm 2.8 that work pretty well in these kinds of settings. The Tamron 28-75 2.8 is great too but a bit more of an investment. An older fast prime or two would help a lot and won't cost you that much. My 135 was $40 on eBay.

It was pretty dark for all three of these shots but manual settings worked great.

K-x & 50mm 1.7



K-x & Sears 135 2.8



K-5 & Tamron 28-75 2.8



For a little more (but still way less than a fast zoom) the DA 40 2.8 works pretty well in the dark too.
K-5 & DA 40mm 2.8




Last edited by mattb123; 01-07-2013 at 11:23 AM.
01-07-2013, 02:45 PM   #24
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QuoteOriginally posted by mattb123 Quote
I was going to suggest shooting manual too. That's what I do in very dark situations that seem to test the limits of the metering system.
Thanks mattb -
with over 3 years' shoot on an almost weekly basis -
one would have thought I might have figured somethings out -
did you see the two shots near the bottom of my opening post #1 (link)?

Here is one of the metering segment LV again:



This is below the metering limit of the K-5 = LV0 - but I managed to both focus and take the exposure:

pasted here again:


Original resized only EXIF attached:


Yes, underexposed by quite a bit - but this was one of the shots that had me wondering about the lowest metering limit of my new K-5 -
(ie: not being able to reach 1/4 sec and K-5 had set 1/15 sec... hence the underexposure (my K-x would have set 1/4 sec)

This has actually now been solved!
Thanks to vonBaloney over in the thread: K-5 lowest metering limit? ( 1 2)
it was the metering pattern:

if I set
matrix - 1/8sec
center weighted - 1/4 sec!
spot metering - 0.3"
01-07-2013, 06:27 PM   #25
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out of interest what did you use to generate the LV charts as above??
01-07-2013, 09:03 PM   #26
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QuoteOriginally posted by milesy Quote
out of interest what did you use to generate the LV charts as above??
It's PhotoME - for Windows (and I think Linux, but not Mac)
- the non-Beta version (v. 0.79R17)
do a cntrl-F and search on "seg"
under AE metering segments click on the link <Graphics> - that will open the window.
01-07-2013, 09:42 PM   #27
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Yesterday was a busy day - first an afternoon gig with two very good acts - but at a venue that favors magenta LED lighting - so basically I had to put all my photos through Pentax DCU -
set gray-point mostly on the mics which gave close to "natural" lit photos -
I then added magenta to the balance to get the photos back to the impression of what I saw -









next was one of my favorite acts that play Django-esque swing jazz -








Just to give an idea of the LED magenta difficulty -
this was one that came out pretty extreme:
Original resized only EXIF attached:


after the post processing -


However mostly it wasn't as bad as that shot -
the first shot - original resized only with EXIF attached:


I was talking to one of the band members and they told me about another gig at the dark jazz club that very night -
guitarist Dave Stryker and organist Tony Monaco were playing -
so I had to go and take pics.....






So now that I know my copy of the K-5 is behaving correctly,
I now have confidence using it for any of the gigs I used the K-x for -
and so far it is for me mostly better than the K-x....
01-08-2013, 01:15 PM   #28
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QuoteOriginally posted by UnknownVT Quote
It's PhotoME - for Windows (and I think Linux, but not Mac)
- the non-Beta version (v. 0.79R17)
do a cntrl-F and search on "seg"
under AE metering segments click on the link <Graphics> - that will open the window.
cool thanks....never knew i could do that
01-11-2013, 02:36 PM   #29
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Back at the dark jazz club with the K-5 -


no, it does not get any brighter there -
and people still wear hats -




Armed with just a bit more knowledge - little as it may be - it was pretty crucial -
now that I know the lowest metering limit for my settings of ISO5000, f/3.5 on the 18-55 kit zoom, 0 comp = 1/8 sec shutter speed for Matrix metering -

I can use the exp comp to dial in any exposure I need, when the light limit drops below the lowest metering limit -
this is what I did here to get this shot:


and this one:

may seem uninteresting with no action -
until one looks more carefully -
there are 3 lit cell phones -

and moments later -


Even though these may not be the highlight shots they are the ones that make this gig so interesting -
lots of musicians plays from off stage to support what is going on stage.....

Then there's outside during the break -










01-18-2013, 03:10 PM   #30
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Same dark jazz venue -










now that I know how the K-5 behaves at or below the metering limit - this has helped with those off stage scenes.


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