[Edvinas]

Pentax DSLRs had broken Hyperprogram when used in Auto ISO for four years (three DSLR models, many firmware updates). Finally in K-5 1.01 firmware they have fixed it!

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Last edited by Edvinas; 11-18-2010 at 02:33 PM.

[RonHendriks1966]

Can you explain what is fixed? Maybe I mist it, having K20D, K-7 and K-5.

[Edvinas]

Can you explain what is fixed? Maybe I mist it, having K20D, K-7 and K-5.

In K10D and K20D ISO is not increased when in HyperTv. HyperAv works OK.

In K-7 in HyperTv aperture closing limit was depending on auto ISO range.
For example, Auto ISO 100-800 and aperture won't be closed beyond f8. Auto ISO from 100 to 1600 and Aperture wont be closed beyond F/5.6, Auto ISO 100-3200 and aperture won't be closed beyond f/4 and so on. These figures can be a little off ― I don't have K-7...

In K-5 v1.00 both HyperTv and HyperAv acted in such erratic manner that I was not really able to figure out what is going on there. Fortunately 1.01 came out and fixed it. Now HyperTv works exactly as Tv and HyperAv works exactly like Av.

[nanok]

when you have auto iso _and_ aperture control (in your example) up to the camera, the camera obviously has to make a choice: what do i change, iso, or aperture? perhaps the algorythms based on which it made these changes were not obvious to you, perhaps they had a reason to make them like that (though if they were different in tv from hypertv, that's a bit strange). maybe it depends on your program line (for instance, if you were in mtf line, it would try to stay close to the aperture sweetspot of the lens, etc). calling it a bug might be a bit "trigger happy".

what really confuses me is how you noticed this? see, if you set auto iso and hypertv, at that point you made a clear statement: do whatever it takes, i want this shutter speed, now. keeping an eye on both aperture and iso, while in hypertv, seems counter productive (much like shooting in M mode, except more stress involved -- i shoot m mode, quite a bit, it's nice to not have anybody to blame ).

--
nanok, walking away confused

[Edvinas]

Well, first of all I want to explain why did I consider it a bug.

Pentax always advertised Hyperprogram's ability to instantly switch to either Tv or Av by turning either front or rear e-dials. I call those modes HyperTv and HyperAv to make difference from Tv and Av modes selected by turning mode dial. This is simple genius idea. In my understanding HyperTv and TV, HyperAv and Av should function in exactly the same manner and K-5 firmware update 1.01 proves my point. Al those program lines are in effect when you have camera mode dial set to P and press green button. When you turn front/rear dial, camera just switches to Tv/Av and that's it. this is my understanding how hyperprogram is working.

Now, how did I notice this. It was much easier to spot broken Hyperprogram in K10D/K20D. ISO was not increased in HyperTV. I've noticed it quite quick on K10D. After that I was testing Hyperprogram + Auto ISO with every firmware update, every new Pentax DSLR with Hypermode ― I wanted to see whether they fixed the problem. And K-5 v1.01 is the first Pentax DSLR where HyperTv and Hyper Av acts exactly the same as Tv and Av both in fixed ISO and Auto ISO.

[nanok]

the probleem with k10 i think was that auto iso wasn't actually working in the hyper p modes, and that, i agree, is annoying to say the least.

thanks for the explanations, maybe i'll give it a try on the k20 and the k-5. i don't use it so much as i have mostly manual lenses, but i do recall the auto iso issue, which was a shame, i agree

[rparmar]

I must be missing something, but why would you want the ISO to change behind your back when in HyperAv mode? When you turn the Av dial, how will you know if the camera is going to adjust ISO or Tv to compensate?

[Arpe]

All I can say is about bloody time!
That is one reason I bought Pentax, but it was broken, so i never used it.

---------- Post added 19th Nov 2010 at 12:55 PM ----------

When you turn the Av dial, how will you know if the camera is going to adjust ISO or Tv to compensate?

It'll probably adjust Tv down to 1/FL, then ISO.
Why should it only adjust Tv?

[nanok]

rparmar: you don't know, and that's the way it's meant to be: you set auto iso, and turned the av dial, you also set the limits for acceptable iso, so what's the problem? you made it clear you want (to take over) control over the aperture, you should not care what happens to everything else. if you want to control all three, you should turn the dial to "M". as arpe points out, some clever algorithms will be appreciated (don't bring shutter down to 1s and keep iso at 100, or bring iso all the way up and shutter to 1/4000), but that's a different story

[Edvinas]

I must be missing something, but why would you want the ISO to change behind your back when in HyperAv mode?

To get proper exposure without blurring picture because of too slow shutter speed.

When you turn the Av dial, how will you know if the camera is going to adjust ISO or Tv to compensate?

Camera tries to keep ISO as low as possible. It will increase ISO only when shutter speed drops to ≈1/focal_length, i.e. to avoid hand shake blur.

After all, as nanok has already said, in Av mode we want to control aperture and it doesn't really matter how camera adjusts Tv and ISO to get the proper exposure.

[blende8]

Pentax DSLRs had broken Hyperprogram when used in Auto ISO for four years (three DSLR models, many firmware updates). Finally in K-5 1.01 firmware they have fixed it!

Cool!
And strange: Why did they fix it exactly now?

[Edvinas]

Cool!
And strange: Why did they fix it exactly now?

In K-7 and K-5 severity of malfunction depended on selected Auto ISO range. On K-7 it was harder to spot malfunction. K-5 sensitivity range is so broad that when upper limit of Auto ISO was very high, HyperTv and HyperAv wasn't working at all, it was not possible not to notice that.

[gazonk]

To get proper exposure without blurring picture because of too slow shutter speed.

More than 90% of the time I shoot Av (and use the front wheel to control ISO, that's so much cooler than having to switch film in my LX where I also used the equivalent of Av most of the time ), but when I want to ensure fast enough shutter speed I always end up using Tav instead of Hyper-program. Since HyperProgram is supposed to be such a cool Pentax feature (and more so now that it's working better) - can you enlighten me about what I'm missing by using Tav instead...?

[Edvinas]

[...]
but when I want to ensure fast enough shutter speed I always end up using Tav instead of Hyper-program.
[...]
can you enlighten me about what I'm missing by using Tav instead...?

I see no reasons to use Hyperprogram instead of TAv. They have different purposes.

[gazonk]

I see no reasons to use Hyperprogram instead of TAv. They have different purposes.

Hmm. I still don't get what the purpose of Hyperprogram is, though

I can understand Program, but ever since I first looked at a Canon A-1 more than 30 years ago I think it's kind of misplaced in an SLR camera. I always (well, since the Canon AE-1 which I think introduced this strange mode) thought that Tv mode was not really that useful compared to Av mode, but I guess the point of HyperProgram is to let you choose between Av and Tv on the fly? But that's IMHO where TAv mode gets interesting now that there are cameras with such huge useful ISO ranges as the K-5 - why use Tv with auto iso and lose aperture control when you can use TAv and keep control over aperture and use the best ISO you can get in the given light?