Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-27-2008, 06:03 PM   #1
Senior Member




Join Date: Sep 2007
Location: Vancouver, BC, Canada
Posts: 131
Why does ev compensation set off auto iso?

I have a k100d and I think it is annoying, when the metering system underexposes and I want to adjust ev compensation to take another shot. Suddenly it becomes iso200 from iso800 and there is handshake.

From what I've read in the manual there is no setting around this. So what do you use? AE lock? Set iso manually? Change the metering mode?

02-27-2008, 06:11 PM   #2
Veteran Member




Join Date: Jun 2007
Location: California
Posts: 426
Set ISO manually, or use Tv mode where you can set a shutterspeed that won't record the shaking.
02-27-2008, 06:52 PM   #3
Veteran Member




Join Date: Dec 2007
Posts: 923
Its an annoying but documented limitation of the K100D's AutoISO.
In addition, any shot with flash on defaults to ISO200 if you use AutoISO.

In any kind of lower lighting where the shutter speed at ISO200 may become too slow, you should manually set the ISO.
02-27-2008, 08:00 PM   #4
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,964
QuoteOriginally posted by kittykat46 Quote
Its an annoying but documented limitation of the K100D's AutoISO.
It really really seems like a bug which they decided to document instead of fix. Pretty annoying -- I'm glad they actually did correct it in the K10D.

02-27-2008, 11:02 PM   #5
Forum Member




Join Date: Dec 2006
Location: Taiwan
Posts: 98
What really bothers me is that Pentax fixed the problem for the K10D (which means it's a fixable firmware bug to me) but decided not to fix it for the K100D.
02-28-2008, 04:20 AM   #6
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
Simple

QuoteOriginally posted by jake123 Quote
I have a k100d and I think it is annoying, when the metering system underexposes and I want to adjust ev compensation to take another shot. Suddenly it becomes iso200 from iso800 and there is handshake.

From what I've read in the manual there is no setting around this. So what do you use? AE lock? Set iso manually? Change the metering mode?
The answer to your question is simple: It's JUST a BUG!

There is no real solution to the problem if you insist on using the Auto ISO. But the compromise is just to disable the Auto ISO and then the trouble will go away. But then you'll loose the Auto ISO feature by doing so! :-( But but as some say, it is not a big deal for without the Auto ISO! ;-) But but but some will say if there is a feature, it *should* work flawlessly.. Well...!
02-28-2008, 05:38 AM   #7
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,964
QuoteOriginally posted by Sideway Quote
What really bothers me is that Pentax fixed the problem for the K10D (which means it's a fixable firmware bug to me) but decided not to fix it for the K100D.
This looks like the way forward, for better or for worse. (Well, worse, mostly, I gotta say.) the K20D has lots of little improvements which could be done in a K10D firmware update but apparently won't be.
02-28-2008, 06:05 AM   #8
Veteran Member




Join Date: Sep 2006
Location: Virginia Beach VA USA
Photos: Gallery
Posts: 1,364
Not necessarily a firmware issue. Remember, The K10D uses totally different components than the K100. Pentax has a very good track record for firmware fixes, where applicable, which leads me to believe it is not a firmware fix. It will be interesting to see if they fixed it in the K200D.

02-28-2008, 06:17 AM   #9
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
QuoteOriginally posted by roscot Quote
Not necessarily a firmware issue. Remember, The K10D uses totally different components than the K100. Pentax has a very good track record for firmware fixes, where applicable, which leads me to believe it is not a firmware fix. It will be interesting to see if they fixed it in the K200D.
I can't think out a reason why the firmware cannot rectify the problem as the Auto ISO is just a *software* algorithm!
02-28-2008, 10:45 AM   #10
Veteran Member




Join Date: Sep 2006
Location: Virginia Beach VA USA
Photos: Gallery
Posts: 1,364
You know, I started to write a sarcastic flip reply to you Rice, but decided it is just not worth the effort to argue with you. you never listen to anyone with a different opinion than your own.

I give up. You are right, you are always right. In fact you are a legend......... in your own mind.

Don't bother to reply, as I won't respond back.
02-28-2008, 02:12 PM   #11
Senior Member




Join Date: Sep 2007
Location: Vancouver, BC, Canada
Posts: 131
Original Poster
Thanks guys. I guess I'll have to live with the nuisance until I upgrade... one day.
02-29-2008, 05:59 AM   #12
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
QuoteOriginally posted by roscot Quote
You know, I started to write a sarcastic flip reply to you Rice, but decided it is just not worth the effort to argue with you. you never listen to anyone with a different opinion than your own.

I give up. You are right, you are always right. In fact you are a legend......... in your own mind.

Don't bother to reply, as I won't respond back.
Alan, I don't know why you should overreact, which is indeed not needed.

I did listen and read what you said but just that I disagreed with your suggestion. And, my point made is simple, that is, the Auto ISO is a PURE *Software* thing. My last statement re-quoted:-

"I can't think out a reason why the firmware cannot rectify the problem as the Auto ISO is just a *software* algorithm!"

To elaborate, the hardware, that is the light meter gives only the EV (Exposure Value) as its output. With the EV value, the camera could know about the environment/subject light level for a given ISO number. As for the Auto ISO, it is just an *algorithm* to raise the ISO number when the *detected* light level (by the light meter, i.e., hardware) is low.

As for the EV compensation, it has NOTHING to do with the hardware, nor, when the software algorithm to decide what ISO should be set, these two independent parameters should have any relationship. Note that the EV compensation is just a simple mathematical addition or subtraction function.

All in all, the Auto ISO is actually a very straight forward thing. I did write those firmware and software program decades ago (well, the died AIWA HiFi equipment, e.g., that why it died ;-)) and if I am asked to write such an Auto ISO algorithm or subroutine with a given EV value as the input, I would say it is just a simple and easy task for me and I have the full confidence to complete the software algorithm just within minutes.

So, afterall, I think your argument of "if Pentax could do it or they were able to do it, they should have done it already" is not substantiated. For example, Pentax could surely write a new firmware subroutine to release the focus adjustment feature like that available in the K20D but they just have not and won't do it forever.

In the end, they are just a company, who runs commercially, and thus needed to keep some features available at higher/newer models and locked those for lower models or older models, so as to differentiate different models and to reserve "motivations" for existing users to upgrade, i.e., to buy new stuff!

Last edited by RiceHigh; 02-29-2008 at 06:05 AM.
02-29-2008, 07:29 AM   #13
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,964
QuoteOriginally posted by roscot Quote
Not necessarily a firmware issue. Remember, The K10D uses totally different components than the K100. Pentax has a very good track record for firmware fixes, where applicable, which leads me to believe it is not a firmware fix. It will be interesting to see if they fixed it in the K200D.
It is a bit odd that they don't recognize this as a bug, but there are other similar things in the K10D (shutter priority in hyperprogram mode) which they haven't fixed either. And this particular one, they knew about early enough to document. It's possible they saw it as one of those features that will steer advanced people to the K10D and entry-level buyers won't know enough to care about. That seems a bit silly in this particular case, though.

But, anyway, I can't imagine why there'd be a hardware limitation here. The analysis that it's a software (which is to say, firmware) problem seems correct to me.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, compensation, dslr, ev, ev compensation, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
[Auto-ISO] so, is the K5 and Kr brave enough to use max iso? Reportage Pentax K-5 13 10-24-2010 03:30 PM
For Sale - Sold: Pentax Bellows II M Set and Auto Extensions Tube Set K (US/CAN) Nick Sold Items 3 08-12-2010 07:07 PM
Pentax DS auto iso with exposure compensation? spystyle Troubleshooting and Beginner Help 5 12-04-2009 05:46 PM
Auto EV Compensation Workingdog Pentax DSLR Discussion 18 09-17-2008 08:25 PM
K10D Auto ISO now works with Exposure Compensation? RiceHigh Pentax DSLR Discussion 15 12-02-2006 06:27 PM



All times are GMT -7. The time now is 07:31 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top