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03-02-2007, 06:09 PM   #16
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QuoteOriginally posted by Dana G Quote
I think it's more critical for Pentax to fix the exposure problems with K and M lenses. That should be the first priority.
I second that emotion (wish I still had my luna pro)
tb

03-02-2007, 06:59 PM   #17
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Since this thread is back in action, I thought I'd add another idea. Here is a proposed change to the preview lever function, in "Optical Preview" mode:

We should be able to pull the lever and hold it back with our index finger while turning the rear dial with our thumb to effect real time adjustment of aperture. Currently, this isn't possible. If the hardware will allow it, DOF evaluation would then become a snap.
03-02-2007, 07:21 PM   #18
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QuoteOriginally posted by borno Quote
I second that emotion (wish I still had my luna pro)
tb
what exposure problems?

I ran a whole series of tests and the green button exposure (which only is to be used in manual mode) worked perfectly.

My critical list is ISO3200 and green button for calculation of apature to make use of P-TTL flash
03-02-2007, 07:22 PM   #19
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QuoteOriginally posted by button Quote
Since this thread is back in action, I thought I'd add another idea. Here is a proposed change to the preview lever function, in "Optical Preview" mode:

We should be able to pull the lever and hold it back with our index finger while turning the rear dial with our thumb to effect real time adjustment of aperture. Currently, this isn't possible. If the hardware will allow it, DOF evaluation would then become a snap.
It would be nice if the optical preview could somehow show the exposure as well, or maybe a quick button to go from optical to digital preview so we can view both.

cheers

randy

03-02-2007, 08:15 PM   #20
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QuoteOriginally posted by Lowell Goudge Quote
what exposure problems?

I ran a whole series of tests and the green button exposure (which only is to be used in manual mode) worked perfectly.

My critical list is ISO3200 and green button for calculation of apature to make use of P-TTL flash
lowell,
When using non-"a" lens or "a" lens using aperture ring at less than about f4 i'll get overexposure usually.It's usually about 1.5 stops depending on the light and the lens I have learned to adjust but itis frustrating.I'm glad I have mostly "a" lenses. I don't think that I'm alone with this one.
tom
03-02-2007, 08:22 PM   #21
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QuoteOriginally posted by borno Quote
lowell,
When using non-"a" lens or "a" lens using aperture ring at less than about f4 i'll get overexposure usually.It's usually about 1.5 stops depending on the light and the lens I have learned to adjust but itis frustrating.I'm glad I have mostly "a" lenses. I don't think that I'm alone with this one.
tom
I hear what you are saying, but I ran a whole series of tests using a pentax M 100 mm F4 macro, starting at F4 and stopping at F32, no problems found. Like I say, what problem? I know people have reported this, but I don't see the problem, and I can't imagine that it is "camera specific"
03-02-2007, 11:01 PM   #22
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This has been diagnosed. The standard brighter screen sold with the K10D doesn't send the light proportionately (as you stop down) to the meter sensor due to the fact that the sensor is off to the side, along with the methods used to make the screen brighter.

At smaller apertures the light falls off unproportionally more and more toward the edges where the sensor reads but stays proportionally bright at the center of the screen where the sensor does not read.. Center weighted setting helps a bit for some reason.

Using a DS screen has corrected the issue because the light is spread more evenly across at all apertures.- though its dimmer.

Larry
03-03-2007, 05:55 AM   #23
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QuoteOriginally posted by mutley Quote
This has been diagnosed. The standard brighter screen sold with the K10D doesn't send the light proportionately (as you stop down) to the meter sensor due to the fact that the sensor is off to the side, along with the methods used to make the screen brighter.

At smaller apertures the light falls off unproportionally more and more toward the edges where the sensor reads but stays proportionally bright at the center of the screen where the sensor does not read.. Center weighted setting helps a bit for some reason.

Using a DS screen has corrected the issue because the light is spread more evenly across at all apertures.- though its dimmer.

Larry
Are you sure about this?

what you are saying implies that manual lenses suffer from light fall off at the edges as the lens is stopped down. In fact to my knowledge, lenses actually work the other way, where light distribution across the field is actually the worst when the lens is wide oen at maximum apature and improves as the lens is stopped down. If this was the case you should see this also if you take a photo of a uniform surface at different f-stops as this is a lens issue not a camera issue.

Additionally you have only two metering modes with manual lenses, spot and average. Sopt metering has the sensor in the center of the frame, hence what ever takes place at the edge does not impact the metering. Have you actually tested this under controlled exposure conditions and especially with a uniform subject to see if it really is the case

03-03-2007, 09:34 AM   #24
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I think that there are some fine ideas here. But let's not forget that some of the things that could be adressed via firmware on the K10D would benefit the K100D and K110D aswell.

Improving the WB is a good enough example.

And I think Ben Kanarek's advice, to contact Pentax directly with ideas of improvement is a good one. It gives them a much clearer info of what is on the minds of actual users.
03-04-2007, 01:12 PM   #25
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QuoteOriginally posted by button Quote
I think the "preview" lever by the power switch should work in the following way:

When in "digital preview" flipping this lever displays histogram data, distributed between 2 screens. The composite histogram should be shown in conjunction with the color histograms, as it currently is on one screen. It should be eliminated on the the other screen and replaced with a vertical row of options as below. Please see attached (crude) JPEG.

1) White balance- make this dial adjustable from 2500-10000K with optional fine tuning, as allowed under the "Fn" menu. No need for "taste" options

2) Saturation, Sharpness, and Contrast- as seen under the "menu" button. Currently, I can't see in real time the effect of adjusting the settings under "menu".

Also, the white balance editor in the JPEG developer under "Fn" should allow for dial adjustable Kelvin settings. As is stands, only the 3 that were chosen in the white balance settings are displayed. Furthermore, the white balance should be Kelvin adjustable in the "Digital Filter" under "menu" when editing JPEGs in camera.

I think that these additions would greatly enhance an already super camera.

John
Also,
Why toggle between preview shot or DOF in menu? Why not both, by taking a preview shot with the lever and keeping aparture at preset value while keeping tension in lever?

(+ as I have suggested in another thread here, make it possible to get fast access to manual white balance by pointing camera to white sheet (etc) by keeping f.ex. EV-button pressed when taking a preview shot (or with shutter release buttton))

Lars
03-04-2007, 03:52 PM   #26
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QuoteOriginally posted by Lowell Goudge Quote
Are you sure about this?

what you are saying implies that manual lenses suffer from light fall off at the edges as the lens is stopped down. In fact to my knowledge, lenses actually work the other way, where light distribution across the field is actually the worst when the lens is wide oen at maximum apature and improves as the lens is stopped down.
This is not an issue of the way the image falls upon the Sony sensor, but the effect this specific new K10D brighter focusing screen disperses the light. I imagine with the metering sensor being off center, maybe when set on spot, it senses there at an angle.

All I know for sure is people have tried the DS screen, and the problem was solved.

The amount of miles you can travel for the same amount of gallons of gas might be different for you than others may experience. (Or something like that).

Larry
03-04-2007, 04:02 PM   #27
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QuoteOriginally posted by mutley Quote
This is not an issue of the way the image falls upon the Sony sensor, but the effect this specific new K10D brighter focusing screen disperses the light. I imagine with the metering sensor being off center, maybe when set on spot, it senses there at an angle.

All I know for sure is people have tried the DS screen, and the problem was solved.

The amount of miles you can travel for the same amount of gallons of gas might be different for you than others may experience. (Or something like that).

Larry
It also shows up with the Katz Eye screens that are used for manual focusing. So perhaps a Katz Eye DS screen would fit into the K10D and work properly?
03-05-2007, 12:12 AM   #28
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QuoteOriginally posted by Dana G Quote
It also shows up with the Katz Eye screens that are used for manual focusing. So perhaps a Katz Eye DS screen would fit into the K10D and work properly?

If it shows up in the K10D with the way Katz Eye makes their screen, then the one made for the DS would be the same. Its the screen itself, not what it fits.

The original DS screen is not optically designed for extra brightness like the original K10D & Katz Eye screens are. The original DS screen is just plain "ground glass" in design. It disperses the light across its surface more evenly than the others enough where it doesn't affect the side mounted metering sensor..

Larry
03-05-2007, 01:39 PM   #29
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QuoteOriginally posted by Lars Quote
Also,
Why toggle between preview shot or DOF in menu? Why not both, by taking a preview shot with the lever and keeping aparture at preset value while keeping tension in lever?

Lars
Lars, I like your push toward increased efficiency. However, for your idea to work, it seems to me that the shutter would have to first open and close to get the preview shot, and then open again (and stay open), to evaluated DOF in optical preview mode, all with one lever pull.

Perhaps the lever pull could work as it already does in optical preview mode, and a button on the opposite side of the camera (the RAW/jpeg, maybe?) could be used to fire the shutter while tension is maintained on the lever, thus allowing the digital preview capture. This way, if our ideas were integrated, the aperture could be adjusted in real time with the rear dial while the lever is pulled, and a digital preview could be acquired when wanted. Viola- an integrated optical/digital preview! This could even be taken a step further, if the camera were to compute the correct shutter speed for the selected aperture, and then retain it for your next shot if in manual or Av priority mode- sort of like a built-in "green button".

John
03-07-2007, 11:39 AM   #30
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John,

I actually meant that you in menu (special settings) have to chose between DOP in viewfinder or to take a preview shot, and I can't see the reason why!

I suppose the order when taking a preview is:
closing aperture down - flipping mirror up - shutter operation - open up aperture (and of course process image and showing on screen).

The only thing that have to be changed is to not open up the aperture until lever is released (or closing it down directly after this sequent). This way you could have it both way (I think). I prefer to check DOP through viewfinder before zooming on screen.


Lars
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