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03-04-2011, 11:39 AM   #16
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I know you've already discussed the NR issue, but I'm inclined to say that it is NR despite the early dismissal. I'm an outsider without a K-5, and I've occasionally been full of it, but just try this one thing first.

Disable NR, redo the test.

I think (I'm guesing) that NR is applied more thoroughly at higher ISOs. So even though you aren't changing NR, the camera is automatically applying more NR to higher ISO images.

Nico has said much the same too. My approach is slightly different only because I'm asking you to turn off NR and try it again. If we are right, the camera will fire quickly. Otherwise, I'm wrong again.

03-04-2011, 11:54 AM   #17
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QuoteOriginally posted by more than a few people Quote
lots of blah-blah about NR.
Please allow me to quote my-self... again...:


QuoteOriginally posted by alexeyga Quote
What does it have to do with the noise reduction if when AUTO-ISO is OFF, camera fires at full 7fps REGARDLESS of the current ISO value??? It's with the AUTO-ISO ON that things tend to slow down in darker conditions...
Yes I admit that English is not my native language... but am I really that bad?

How about this, same settings for same settings:
1)ISO is set manually to 51200, camera fires at 7FPS
2)ISO is set to AUTO and under same dim light and same subject burst rate falls to ~3FPS despite the fact that shutter speed is still faster than 1/50th...

Now, can anybody tell me what does NR has to do with it?
03-04-2011, 12:14 PM   #18
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QuoteOriginally posted by alexeyga Quote
Actually Pentax's implementation of AUTO-ISO is one of the best on the market... for an average Joe that is... When shutter speed is not fixed, it's a function of the current focal length. I don't remember about K7, but in K5 there are 3 different curves for the AUTO-ISO "aggressiveness" that you can define depending on your needs or shakiness of your hands... so at the slowest setting camera goes wondering into theoretical minimum shutter speed limit for that FL way before bumping up the ISO...

Having rather extensive experience with Nikon's auto-iso, my only wish so far is to have a way of defining the minimum shutter speed limit as I do sports and often don't want to go below 1/500th...
I think you want to be in Tv mode for that,

If you like auto ISO then you have not tried flash. Can't comment on K5, have not decided to get one yet, but on all other cameras, it will take ISO to max first, as opposed to using flash power, and only add flash for the shortfall between auto iso limit and exposure limit.

Note also in flash mode, in auto modes, the camera will follow the rule of thumb for shutter speed (if below sync speed) first, before adding flash. so on a 28mm lens it will go down to 1/30 first trying to make exposure up with flash.
03-04-2011, 12:49 PM   #19
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QuoteOriginally posted by Lowell Goudge Quote
I think you want to be in Tv mode for that
Not really, Tv sets a hard limit for the shutter speed... what I need is a possibility to set the lower limit only with upper limit being 1/8000th... this way whenever there's too much light for both current shutter speed and iso, camera will just bump up the shutter speed instead of overexposing...

The whole beauty of AUTO-ISO - one thing less to worry about while shooting... if it's done properly....


QuoteOriginally posted by Lowell Goudge Quote
If you like auto ISO then you have not tried flash. Can't comment on K5, have not decided to get one yet, but on all other cameras, it will take ISO to max first, as opposed to using flash power, and only add flash for the shortfall between auto iso limit and exposure limit.

Note also in flash mode, in auto modes, the camera will follow the rule of thumb for shutter speed (if below sync speed) first, before adding flash. so on a 28mm lens it will go down to 1/30 first trying to make exposure up with flash.
I haven't done enough flash work with K5 to be able to judge, but all the late Nikon cameras (starting with D300s) do follow what you've just said... However, all Nikon flashes by default work in "ambient" mode, all you have to do is disable it for the camera to start bumping flash output instead of bumping ISO... not a biggie if you know what you're doing...

03-04-2011, 01:35 PM   #20
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Well everybody thinks its NR, everybody asks you to try the test with NR turned off, and you keep talking about Auto-ISO. Sure, you've shown that Auto-ISO can cause the problem. We want to know if turning NR off will allow Auto-ISO to work. I don't see the part where you answer that question in english or any other language. I'm not the first in this thread to suggest this either.

It might not change your results, but on the other hand it might. If I had a K-5 I would test this myself and let you know. But I don't so I can't. If you don't want to try it then maybe someone else here can.
03-04-2011, 01:47 PM   #21
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for f@#$@#'s sake... ISO set manually to 6400, camera applies NR and keeps shooting at 7FPS... ISO set to AUTO, camera bumps it to 6400, applies the same exact NR, but slows down to 3fps for some stupid reason... what's so hard to understand?

better yet, camera set to AUTO-ISO, it's dark enough for ISO to go to that same 6400 and I freeze the exposure with AE-L... camera shoots at 7FPS while applying the same stupid NR...

WTF does it have to do with NR??? The only variable here is AUTO-ISO being ON/OFF/over-ruled by AE-L.... the rest is exactly the same...
03-04-2011, 01:56 PM   #22
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Sorry I got you so riled up, alexeyga. Its nothing personal.

You are suggesting that because Auto-ISO is shown to cause the delay then this isn't an NR issue. All I'm saying is that if NR is turned off, then maybe Auto-ISO will work with similar results as you've seen with manual ISO. This is possible because the K-5 has a little computer processing data, and I've seen enough computers screw up to know that seemingly unrelated settings can have unintended consequences. Computers are only as smart as their programmers. Here, it seems that the delay is best explained by NR. The best way to determine this is to turn off NR. I don't care that it seems to be linked to Auto-ISO right now, I want to see what the effect of NR is.

Maybe someone else with a K-5 can look at this to satisfy my curiosity. I'm not starting a new thread because half of the people in this thread think I'm on topic.
03-04-2011, 03:07 PM   #23
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No, there's no effect of NR being OFF...


Could somebody please close the topic? I think I'll have more success in farmlands with chickens finding out why they want to cross the road...

03-04-2011, 03:27 PM   #24
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If OP wants to close this thread, I'd prefer instead that he choose not to continue participating. I thank him for helping with my previous question.

Could someone else who is interested in finding out what is going on help now?

I think it would be fun to see if NR is actually being applied despite the NR being turned off. Set AutoISO on, turn off NR, take a photo such that the delay is noticed, and examine the photo to see if NR is applied anyway.
03-04-2011, 04:00 PM   #25
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OK, I just tried the experiment with my K-5.

I don't have the 18-135 though, so used the closest thing I have , the 18-55 kit lens.

Exactly the same settings. (Av, auto ISO, hi frame rate,raw, shadow, highlight and lens correction off. Tried the experiment with noise reduction on and off.

Point it out the window, ISO goes to 80, rat a tat tat. 7 frames per second for about 22 frames. (it takes quite a while to process all that data.)

Point it under my desk, ISO goes to 10,000. Exactly the same frame rate.

Am I missing something? There doesn't seem to be a problem with my K-5.
03-07-2011, 04:17 AM   #26
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This weekend I had a shootout with my K5 at an indoor sport event. I used TAv, AF-C and the ISO jumped up to 5000. I did not experience that the framerate dropped down to 3 FPS.
03-08-2011, 04:48 AM   #27
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Just been to the Pentax Japan home page and looking at the firmware updates for the K5 it mention a fix for frame rate problems in higher ISO settings.
Doesn't go into a lot of detail but have you done the Firmware updates or are you running an early version??
Have a look this may be something to do with your issues.
03-19-2011, 06:44 PM   #28
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Just did a test on my K5 (firmware 1.03)

with the following settings
AV,F1.7 (wide open), AUTO ISO (80-6400),Highight of,Shaddow off, CP off etc, AF-S, JPG 3star 16mp,SR ON. SD card removed to eliminate card writing issue

AT High ISO the frame rate will go down in dim lit areas, but if pointed to a light source FPS goes up. something simmilar happens to my K20. (perhaps it's a pentax thing)

I turned NR and Slow shutter NR off but FPS is still low....the only fix around i know of is AE-L with AF locked (Custom 5) set to ON it seems to remedy the issue.

so from what i can conclude...
NR being on or off will do nothing with increase or decrease on FPS
Slow shutter NR set to on or off will not do anything either.
SR on or aff has no affect
AF set to S,C or MF also has no affect.
Auto ISO Paramaters set to SLOW,AUTO or FAST seems not to increase or decrease framerate.

so it seems as long as AE-L is on frame rate stays near the 7fps mark.

I think if the camera is using AUTO ISO and there is low contrast in the frame the FPS seems to slow down. When there is significant contrast, ie.pointed to a lightsource etc FPS is fine. Perhaps there is some setting that i over looked or missed.

If you need AE-L off then a workaround i have found is if you press the AE-lock button on the K5 body before you press the shutter you will be able to sustain 7FPS regardless of AUTO ISO and AE-L with AF Locked(C5) settings


i hope this helps...

cheers!
Ben
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