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03-04-2016, 06:14 PM   #76
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QuoteOriginally posted by clackers Quote
For accuracy reasons, you're much better off focusing wide open, with the smallest depth of field and most light, than at the shooting aperture.

That green button is great.
Yes, which is why the Canon solution is not as terrific as it might at first appear to be {look at my new avatar!}

03-04-2016, 08:03 PM   #77
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QuoteOriginally posted by reh321 Quote
However, note the title of this thread - the OP's initial complaint seems to be primarily about the [COLOR=Lime]green button[COLOR=Black]. I'm getting so tired of those complaints that I'm seriously thinking of replacing my current avatar with a picture of the corner of my K-30 where the [COLOR=Lime]green button[COLOR=Black] rests, mostly not used. NOTE: mission accomplished -see my new avatar
the green button haters are gonna have to put you on ignore to get away from it

QuoteOriginally posted by reh321 Quote
When you mount one of those lenses on a modern Pentax camera, the lens automatically opens to its widest aperture for composing and focusing; you have to press the [COLOR=Lime]green button[COLOR=Black] to get it to meter at the set aperture {incidentally, I believe that the "modern" LiveView you espouse would labor under the same "handicap"}.
that's actually true to some extent, but for different reasons... when there are 399 pdaf sensors covering most of the sensor, af works best at wide open aperture, especially on a fast lens... sony changed the a7rii to open the aperture all the way up to af with some lenses, then stop down to take the shot.

unfortunately it caused problems, and afaik it can't be defeated, with those few lenses that use it... you don't need to do it with legacy glass, because with wysiwg the evf automatically brightens up to compensate.

the o.p. is right to not like it with his old glass, because of focus shifting... all three of my 50/1.4 taks have serious focus shift off of f/1.4, it's easy to see in the evf, and i have a couple of slow lenses that actually have focus shift further up the aperture range, not off of wide open aperture.
03-06-2016, 03:09 AM   #78
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Some have said that the "Green Button" (AKA stop-down metering) is very good on the existing APSC Pentax cameras, IMO this is only partially correct.
K7, K5 work very accurately, K3 and K3-II not very well at all. Pentax say in their manuals that stop-down metering is approximate only (or some other words to this effect). Indeed my extensive collection of both "K" and "M" and also M42 lenses don't meter accurately with my K3, some are spot-on, others can miss by up to 2EV under or over (it depends very much on the "scene" being shot.

If all else fails, you can use a free light-meter app on your smartphone, or purchase a dedicated light-meter. The app is surprisingly much more accurate than the K3!

I hope the stop-down metering on the K1 is better....
03-06-2016, 03:24 PM   #79
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QuoteOriginally posted by jackassp Quote
...

If all else fails, you can use a free light-meter app on your smartphone, or purchase a dedicated light-meter. The app is surprisingly much more accurate than the K3!

I hope the stop-down metering on the K1 is better....
do you recommend an app for cost ?
i prefer to not use free (often ad-ware) stuffs.

i am looking through little apps now. i am not sure i will get one but it amuses me to think about it. i figure the effectiveness or accuracy depends upon the phone itself..? if so, this is one thing where iphone seems to make sense; the developer will know the hardware.

03-06-2016, 03:25 PM   #80
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duplicate post. page churning and loading. refreshing thread page, see nothing, try again. then.. then two posts pop out at once.
03-06-2016, 08:27 PM   #81
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QuoteOriginally posted by Tan68 Quote
do you recommend an app for cost ?
i prefer to not use free (often ad-ware) stuffs.

i am looking through little apps now. i am not sure i will get one but it amuses me to think about it. i figure the effectiveness or accuracy depends upon the phone itself..? if so, this is one thing where iphone seems to make sense; the developer will know the hardware.

The ones I've tried always seemed erratic to me.


If anyone knows a good one, I'd love to give it a go.
03-07-2016, 01:13 AM   #82
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Why on earth would I use an app or a dedicated light meter when I have a digital camera with a histogram? I donít get it.
Shoot, adjust and repeat until perfect. (Use digital preview if you don't want to keep the test shots.)
03-07-2016, 02:15 AM   #83
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QuoteOriginally posted by Gimbal Quote
Why on earth would I use an app or a dedicated light meter when I have a digital camera with a histogram? I donít get it.
That only works in LiveView. Jackassp was talking about not using the green button with the OVF.

Btw, the camera only gives a reflected light reading, not an incident one.

03-07-2016, 02:36 AM   #84
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QuoteOriginally posted by clackers Quote
That only works in LiveView. Jackassp was talking about not using the green button with the OVF.

Btw, the camera only gives a reflected light reading, not an incident one.
I rarely use live view, but I often use the 3 sec preview. So after the shot the result is displayed and I can see if adjustment is needed.

As for the reflected vs incident light, itís the light that sticks on the sensor that counts. So you canít beat the actual image sensor with any external light sensor.
03-07-2016, 02:43 AM   #85
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QuoteOriginally posted by Gimbal Quote
when I have a digital camera with a histogram?
Histograms are only a JPG approximation of the tonality that is present within the scene, they are subject to your cameras JPG processing parameters. Which no matter how hard you try, are never completely neutral.

QuoteOriginally posted by Gimbal Quote
you can’t beat the actual image sensor with any external light sensor.
If you are working with flash LV metering is useless. A handheld light meter is more accurate with flash exposure than the sensor.
03-07-2016, 03:12 AM   #86
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QuoteOriginally posted by Digitalis Quote
Histograms are only a JPG approximation of the tonality that is present within the scene, they are subject to your cameras JPG processing parameters. Which no matter how hard you try, are never completely neutral..
Right, but I doubt you get better precision with an external meter.


QuoteOriginally posted by Digitalis Quote
If you are working with flash LV metering is useless. A handheld light meter is more accurate with flash exposure than the sensor.
You shouldnít use LV metering, you take testshoots (digital preview).
But ok, I never use flashes so maybe there is some benefits there, that I donít know much about.
03-07-2016, 03:50 AM   #87
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QuoteOriginally posted by Gimbal Quote
ight, but I doubt you get better precision with an external meter.
My Hand held light meters are accurate down to 1/16th of a stop, when you are controlling finely tuned flash ratios 1/3rd stop accuracy doesn't cut it.
03-07-2016, 09:02 AM   #88
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QuoteOriginally posted by jackassp Quote
Some have said that the "Green Button" (AKA stop-down metering) is very good on the existing APSC Pentax cameras, IMO this is only partially correct.
K7, K5 work very accurately, K3 and K3-II not very well at all. Pentax say in their manuals that stop-down metering is approximate only (or some other words to this effect). Indeed my extensive collection of both "K" and "M" and also M42 lenses don't meter accurately with my K3, some are spot-on, others can miss by up to 2EV under or over (it depends very much on the "scene" being shot.

If all else fails, you can use a free light-meter app on your smartphone, or purchase a dedicated light-meter. The app is surprisingly much more accurate than the K3!

I hope the stop-down metering on the K1 is better....
If you have time to use a light meter, wouldn't you have time to take a picture using the setting determined by the Green Button, and then try again? {light metered by my film Pentax cameras was typically not right-on, which was more important with the Kodachrome 25 I was using then than it is with PP-able digital, so even when I couldn't get instant feedback I got into the habit of bracketing my pictures}
03-07-2016, 02:46 PM   #89
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QuoteOriginally posted by Digitalis Quote
If you are working with flash LV metering is useless.
it's certainly useless with pentax lv(no wysiwg), but the display on my sony attempts to compensate for fill flash that's added to the scene... accuracy varies, tho

waiting to see if the k1 has wysiwg...
03-07-2016, 05:46 PM   #90
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QuoteOriginally posted by osv Quote
it's certainly useless with pentax lv(no wysiwg), but the display on my sony attempts to compensate for fill flash that's added to the scene... accuracy varies, tho

waiting to see if the k1 has wysiwg...
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