Pentax KX (35mm)

AquaDome · 05-31-2015, 09:38 PM

The optics for the aperture display in the KX viewfinder can get knocked out of alignment. I have four of them and only two display the aperture.

fwcetus · 06-01-2015, 06:02 AM

Originally posted by monochrome

Usually black symbol on white background.

(Not that I ever lost sleep over it, but) I could never figure out why the aperture display appears as a negative (i.e., it shows the white aperture numerals on a black aperture ring as dark numerals on a light background).

CarlH · 06-01-2015, 06:16 AM

the numbers look black on a white background because of the angle of the light bouncing off the ring into the window.
hold the camera directly under a light and the numbers are white.

fwcetus · 06-01-2015, 06:22 AM

Originally posted by CarlH

the numbers look black on a white background because of the angle of the light bouncing off the ring into the window.
hold the camera directly under a light and the numbers are white.

Thanks, Carl. I guess now I now can not "not lose sleep over it" anymore - LOL. (Actually, I did notice that before.

)

I know the LX uses this "rabbit hole" window to show the aperture (I was using an LX just yesterday), but I was just wondering if the LX is the last Pentax body to do so...

Last edited by fwcetus; 06-01-2015 at 06:31 AM.

**ChrisPlatt** · 06-01-2015, 01:34 PM

FWIW Nikon called their near-identical system "Aperture Direct Readout", a name I much prefer to biblical or other literary references.

Chris

johnha · 06-01-2015, 02:41 PM

Originally posted by fwcetus

Thanks, Carl. I guess now I now can not "not lose sleep over it" anymore - LOL. (Actually, I did notice that before.

)

I know the LX uses this "rabbit hole" window to show the aperture (I was using an LX just yesterday), but I was just wondering if the LX is the last Pentax body to do so...

The appearance of the aperture depends on lighting conditions and the lenses used. With lenses with engraved (rather than 'printed') aperture markings, it depends on the angle of light hitting the engravings. With printed aperture rings, you always get 'positive' images but sometimes if the angle is wrong you get nothing at all.

The LX was the last body for sale with the direct readout.

John.

fwcetus · 06-01-2015, 05:23 PM

Originally posted by johnha

The appearance of the aperture depends on lighting conditions and the lenses used. With lenses with engraved (rather than 'printed') aperture markings, it depends on the angle of light hitting the engravings. With printed aperture rings, you always get 'positive' images but sometimes if the angle is wrong you get nothing at all.

The LX was the last body for sale with the direct readout.

Good points, John -- I just tested your comments, and you're quite correct (but you knew that already, eh?).

As for the end of the "little aperture reflection window", I suppose it was all due to the changeover to a combination of exposure automation and digital readouts in cam bodies. In Pentax, specifically, following the various ES models and the K2 models, the M bodies (with the exception of the all-manual MX, of course) emphasized aperture priority exposures, although some (e.g., ME Super, ME F) did also allow manual settings. [And, I tend to suspect that aperture priority made frequent "peeking" at the aperture from the viewfinder less and less important, perhaps paradoxically.] Then, with the A bodies, shutter priority and program modes were added, and exposure settings were displayed in digital readouts. So, I guess the LX was the last run for that little "aperture aperture". However, thanks to some of us classic Pentax aficionados, the "peek at the aperture peephole" does live on in our continued, or renewed, use of the KX, MX, and LX bodies. But I digress...

titrisol · 06-02-2015, 01:53 PM

Mine look like this:

Pentax KX_Viewfinder by titrisol,

The judas windows is weird but it works fine

CarlH · 06-02-2015, 02:05 PM

just curious as to how you take a picture of the viewfinder?

stevebrot · 06-03-2015, 04:23 PM

Originally posted by ChrisPlatt

FWIW Nikon called their near-identical system "Aperture Direct Readout", a name I much prefer to biblical or other literary references.

Chris

Me too. The term "Judas Window" comes to us from architecture, meaning any small window or peephole designed to allow surreptitious viewing. How that designation relates to the Biblical character (if at all) is a mystery.

I remember one user on this site who objected to the term because they thought it racist

Steve

fwcetus · 06-03-2015, 06:02 PM

I'm gonna call it, simply, the "Aperture Aperture" from now on.

(My only film body left that still has one is my LX,)

Fiddler · 06-06-2015, 07:10 PM

Just a little Judas Window update, I now see the Window in the Viewfinder. The "Chimney" on the front the Prism, was in fact bent in to far.Once coaxed out to a more or less Vertical position , the light shone through.

Karénine · 06-07-2015, 02:35 AM

My aperture reader on the KX is also offset. With or without a lens mounted it is dead black. Maybe there's a very thin line of light at the bottom of the aperture reader display but it doesn't work anyway. I'm very much in love with the match needle metering.I almost always use the KX by setting the aperture first, then the exposure and sometimes I need to correct the aperture (for example if it's an hand held shot and the corresponding exposure is under 1/60 or 1/30). Then I have to look at the lens again to see the aperture and I loose too much time on the settings. So i'd like to fix this aperture reader problem.

Has someone have photos or infos on how to access the aperture reader system and fix it ? How to remove the top plate of the KX ? etc. Is it any complicated ? If possible i'd like to avoid giving it to a mechanic, everything else works properly and i'd prefer spending my money on lenses ! (Bièvres international photofair today yeahhhh)

stevebrot · 06-07-2015, 08:25 AM

Originally posted by Karénine

Has someone have photos or infos on how to access the aperture reader system and fix it ?

Adjustment requires removal of the top cover. That can be easy or hard depending on whether you have the tools and have done it before. Once that is off the parts to adjust are as in the photos above. FWIW, my KX is currently in the shop having the adjustment made.

Steve

Fiddler · 06-07-2015, 09:21 AM

If you don't have dedicated tools , Home made or purchased , I would suggest don't attempt it.

Not difficult, but one wrong turn can cause heartache. I only started Fiddling with Cameras fairly recently , but I had little money invested and no emotional attachment to them. So, If I messed up, No worries.

Send it out to Eric and be sure of success.

06-01-2015, 05:23 PM	#22
fwcetus Site Supporter Join Date: Sep 2006 Location: New England Photos: Gallery \| Albums Posts: 1,286	That Little "Aperture Aperture" Originally posted by johnha The appearance of the aperture depends on lighting conditions and the lenses used. With lenses with engraved (rather than 'printed') aperture markings, it depends on the angle of light hitting the engravings. With printed aperture rings, you always get 'positive' images but sometimes if the angle is wrong you get nothing at all. The LX was the last body for sale with the direct readout. Good points, John -- I just tested your comments, and you're quite correct (but you knew that already, eh?). As for the end of the "little aperture reflection window", I suppose it was all due to the changeover to a combination of exposure automation and digital readouts in cam bodies. In Pentax, specifically, following the various ES models and the K2 models, the M bodies (with the exception of the all-manual MX, of course) emphasized aperture priority exposures, although some (e.g., ME Super, ME F) did also allow manual settings. [And, I tend to suspect that aperture priority made frequent "peeking" at the aperture from the viewfinder less and less important, perhaps paradoxically.] Then, with the A bodies, shutter priority and program modes were added, and exposure settings were displayed in digital readouts. So, I guess the LX was the last run for that little "aperture aperture". However, thanks to some of us classic Pentax aficionados, the "peek at the aperture peephole" does live on in our continued, or renewed, use of the KX, MX, and LX bodies. But I digress...

06-06-2015, 07:10 PM	#27
Fiddler Forum Member Join Date: Jan 2015 Location: Arizona Posts: 57 Original Poster	Fixed Just a little Judas Window update, I now see the Window in the Viewfinder. The "Chimney" on the front the Prism, was in fact bent in to far.Once coaxed out to a more or less Vertical position , the light shone through.

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05-31-2015, 09:38 PM	#16
AquaDome Veteran Member Join Date: Jan 2014 Location: New Carlisle, IN Photos: Gallery \| Albums Posts: 1,475	The optics for the aperture display in the KX viewfinder can get knocked out of alignment. I have four of them and only two display the aperture.

06-01-2015, 06:02 AM	#17
fwcetus Site Supporter Join Date: Sep 2006 Location: New England Photos: Gallery \| Albums Posts: 1,286	Originally posted by monochrome Usually black symbol on white background. (Not that I ever lost sleep over it, but) I could never figure out why the aperture display appears as a negative (i.e., it shows the white aperture numerals on a black aperture ring as dark numerals on a light background).

06-01-2015, 06:16 AM	#18
CarlH Forum Member Join Date: Jun 2014 Location: Carlisle, Cumbria Posts: 58	the numbers look black on a white background because of the angle of the light bouncing off the ring into the window. hold the camera directly under a light and the numbers are white.

06-01-2015, 06:22 AM	#19
fwcetus Site Supporter Join Date: Sep 2006 Location: New England Photos: Gallery \| Albums Posts: 1,286	Originally posted by CarlH the numbers look black on a white background because of the angle of the light bouncing off the ring into the window. hold the camera directly under a light and the numbers are white. Thanks, Carl. I guess now I now can not "not lose sleep over it" anymore - LOL. (Actually, I did notice that before. ) I know the LX uses this "rabbit hole" window to show the aperture (I was using an LX just yesterday), but I was just wondering if the LX is the last Pentax body to do so... Last edited by fwcetus; 06-01-2015 at 06:31 AM.

06-01-2015, 01:34 PM	#20
ChrisPlatt Site Supporter Join Date: Nov 2007 Location: Rockaway Beach NYC Posts: 7,696	FWIW Nikon called their near-identical system "Aperture Direct Readout", a name I much prefer to biblical or other literary references. Chris

06-01-2015, 02:41 PM	#21
johnha Veteran Member Join Date: Apr 2012 Location: Lancashire, UK Photos: Albums Posts: 1,155	Originally posted by fwcetus Thanks, Carl. I guess now I now can not "not lose sleep over it" anymore - LOL. (Actually, I did notice that before. ) I know the LX uses this "rabbit hole" window to show the aperture (I was using an LX just yesterday), but I was just wondering if the LX is the last Pentax body to do so... The appearance of the aperture depends on lighting conditions and the lenses used. With lenses with engraved (rather than 'printed') aperture markings, it depends on the angle of light hitting the engravings. With printed aperture rings, you always get 'positive' images but sometimes if the angle is wrong you get nothing at all. The LX was the last body for sale with the direct readout. John.

06-02-2015, 01:53 PM	#23
titrisol Pentaxian Join Date: Dec 2007 Location: In the most populated state... state of denial Photos: Gallery \| Albums Posts: 1,854	Mine look like this: Pentax KX_Viewfinder by titrisol, The judas windows is weird but it works fine

06-02-2015, 02:05 PM	#24
CarlH Forum Member Join Date: Jun 2014 Location: Carlisle, Cumbria Posts: 58	just curious as to how you take a picture of the viewfinder?

06-03-2015, 04:23 PM	#25
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by ChrisPlatt FWIW Nikon called their near-identical system "Aperture Direct Readout", a name I much prefer to biblical or other literary references. Chris Me too. The term "Judas Window" comes to us from architecture, meaning any small window or peephole designed to allow surreptitious viewing. How that designation relates to the Biblical character (if at all) is a mystery. I remember one user on this site who objected to the term because they thought it racist Steve

06-03-2015, 06:02 PM	#26
fwcetus Site Supporter Join Date: Sep 2006 Location: New England Photos: Gallery \| Albums Posts: 1,286	I'm gonna call it, simply, the "Aperture Aperture" from now on. (My only film body left that still has one is my LX,)

06-07-2015, 02:35 AM	#28
Karénine New Member Join Date: Oct 2014 Posts: 19	My aperture reader on the KX is also offset. With or without a lens mounted it is dead black. Maybe there's a very thin line of light at the bottom of the aperture reader display but it doesn't work anyway. I'm very much in love with the match needle metering.I almost always use the KX by setting the aperture first, then the exposure and sometimes I need to correct the aperture (for example if it's an hand held shot and the corresponding exposure is under 1/60 or 1/30). Then I have to look at the lens again to see the aperture and I loose too much time on the settings. So i'd like to fix this aperture reader problem. Has someone have photos or infos on how to access the aperture reader system and fix it ? How to remove the top plate of the KX ? etc. Is it any complicated ? If possible i'd like to avoid giving it to a mechanic, everything else works properly and i'd prefer spending my money on lenses ! (Bièvres international photofair today yeahhhh)

06-07-2015, 08:25 AM	#29
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Karénine Has someone have photos or infos on how to access the aperture reader system and fix it ? Adjustment requires removal of the top cover. That can be easy or hard depending on whether you have the tools and have done it before. Once that is off the parts to adjust are as in the photos above. FWIW, my KX is currently in the shop having the adjustment made. Steve

06-07-2015, 09:21 AM	#30
Fiddler Forum Member Join Date: Jan 2015 Location: Arizona Posts: 57 Original Poster	If you don't have dedicated tools , Home made or purchased , I would suggest don't attempt it. Not difficult, but one wrong turn can cause heartache. I only started Fiddling with Cameras fairly recently , but I had little money invested and no emotional attachment to them. So, If I messed up, No worries. Send it out to Eric and be sure of success.