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08-31-2010, 10:50 AM   #1
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How do i use this lens on my K-x??

I have already removed the Ricoh pin.
I have already set my camera to allow the use of manual Aperture ring.
My understanding is that the Aperture stays all the way open and will reduce to the set aperture on the ring when the photo is taken. I have read about this in the manual, and i have read the sticky on using manual lenses (Using Manual Lenses (M42 Screwmount, M , K) on Pentax DSLRs F--)

Is there another way to meter the camera besides the Green button?

Do i HAVE to shoot on Manual mode? (<---Most important question) What does the "(A)P" mean on the left of the aperture ring?

Can someone help?
Here are some photos of said lens.

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08-31-2010, 11:07 AM   #2
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Looks like the aperture ring has an A setting. Have you tried using it on your camera with that? If that is an A setting then it'll work in all modes normally.

I have a K10D and K100D. On those cameras, here's what you can do:

1. Put the camera in Av. It'll work as normal, except that you can only shoot wide-open.

2. in Manual mode, press the green button.

3. in Manual mode, pull the on switch past "On" into the aperture-symbol thingy. This is your aperture preview mode. While stopped down, you can twiddle the aperture ring and the shutter speed. There should be a graphic indicator or readout telling you how far over/under you are. It's like metering with a K1000 or MX.

For the last option, make sure in the menus you have preview set to optical, not digital.
08-31-2010, 11:39 AM   #3
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If you set it to A, press the button and turn past F22, it should work in Av, Tv or Sv. Use the e-dial to change aperture or shutter speed or ISO.

If you want to use it in full manual as unixrevolution says you have to set the green button to optical preview using menu 4. On the K-x you can use the Av+- button the way you use the green button on other cameras, pressing it will stop down the camera and set the exposure. This is a holdover from the K-m. This lets you use the green button for other functions.
08-31-2010, 11:39 AM   #4
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Ricoh called its A(aperture) setting P(rogram). Third-party lensmakers targeting both Pentax and Ricoh users labeled that mark A(P) so the Ricoh folks wouldn't feel left out. It is exactly the same as the A setting on a Pentax-A or -K lens. If you turn the ring to the A(P) mark, you can shoot in ANY mode, not just M(anual). Congratulations! You have an A-lens!

Oh yeah, the KR there is a dead giveaway -- it means (Pentax-)K-Ricoh mount. Just out of curiosity, is the lens stamped "MADE IN KOREA - SEARS MOD NO. 202" ??

08-31-2010, 12:00 PM   #5
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LOL i never tired the lens with the ring on (A)P and it works!! yay.

A little Weirdness tho, the Aperture on the LCD goes down to 2.5, yet the maximum on the lens says 3.5, whats going on here?

Also the only thing the Av+- button does is let me change the EV compensation. Unless i'm not using it on the right mode, havent tried the P mode yet.

It says "lens made in Korea" no mention of sears at all anywhere.
08-31-2010, 12:01 PM   #6
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QuoteOriginally posted by Silverkarn Quote
LOL i never tired the lens with the ring on (A)P and it works!! yay.

A little Weirdness tho, the Aperture on the LCD goes down to 2.5, yet the maximum on the lens says 3.5, whats going on here?

Also the only thing the Av+- button does is let me change the EV compensation. Unless i'm not using it on the right mode, havent tried the P mode yet.
The Av+- button only works as the green button in M mode. Otherwise it changes EV.
08-31-2010, 12:17 PM   #7
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QuoteOriginally posted by boriscleto Quote
The Av+- button only works as the green button in M mode. Otherwise it changes EV.

Thanks, if this was mentioned in the manual i must have missed it.
Anyone have any info as to why the lens says F3.9 maximum but i can put the camera to F2.5 on the LCD
08-31-2010, 06:27 PM   #8
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QuoteOriginally posted by Silverkarn Quote
Anyone have any info as to why the lens says F3.9 maximum but i can put the camera to F2.5 on the LCD
Hmmm, when using M-type or other non-A-type lenses on my K20D, which have no way of communicating aperture info to the camera, the screen often display invented f-stop numbers. I only have a few A-type lenses and have never seen that -- in fact, I just tested a couple, including a lens similar to yours. My only guess is that the pins aren't making good contact. Take a Teflon eraser and gently go over the lens contacts, see if that makes a difference. I suggest Teflon because then you won't get specks of rubber bouncing around in the camera.

08-31-2010, 06:34 PM   #9
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Like many of the Ricoh P lens, they only work on M mode - to use green button to meter. If you change to A mode, it will stay at wide-open aperture.
08-31-2010, 06:50 PM   #10
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QuoteOriginally posted by aleonx3 Quote
Like many of the Ricoh P lens, they only work on M mode - to use green button to meter. If you change to A mode, it will stay at wide-open aperture.
Nope. See that pin at the 4 o'clock position in the first photo. That's the Pentax A pin. As to why the camera thinks it can do F2.5, I have no idea. Did you put everything back together right?
08-31-2010, 07:10 PM   #11
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QuoteOriginally posted by boriscleto Quote
Nope. See that pin at the 4 o'clock position in the first photo. That's the Pentax A pin. As to why the camera thinks it can do F2.5, I have no idea. Did you put everything back together right?

I think it was a dirty contact, i had some lens cleaning cloths so i rubbed the pin and the contact on the camera, now it only goes down to F4.0, which is close enough to 3.9 for me.

I've been taking some photos with the lens, and they all look soft with some purple fringing at 100% so i'm going to take some photos tomorrow with a tripod and the mirror raised to see if it is my technique.
09-01-2010, 05:08 AM   #12
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QuoteOriginally posted by Silverkarn Quote
I think it was a dirty contact, i had some lens cleaning cloths so i rubbed the pin and the contact on the camera, now it only goes down to F4.0, which is close enough to 3.9 for me.
.
Note that the pentax aperture coding does not allow for all the crazy F stop possibilities.

the 5 pin coding only increments in 1.2 stops so F3.9 is probably coded to F4, in the same way that th epentax 135F1.8 is coded as F1.7.
09-01-2010, 06:57 AM   #13
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Yeah it looks like 3.9, which is still very rare to me, is the widest aperture marking of the lens. f3.9? Very strange.
This lens has the markings of being marketed by a company called Focal.
It has similar script and lettering to my Focal QII 70-210 f4. We have a thread about it deep in the Lens Discussion and you can search for it in the Third Party Lens Review section.
09-01-2010, 09:13 AM   #14
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QuoteOriginally posted by Nowhere Matt Quote
Yeah it looks like 3.9, which is still very rare to me, is the widest aperture marking of the lens. f3.9? Very strange.
I have a Korean-made (probably Samyang) cousin of that lens (Nikon mount, Albinar badge) that's f/3.9, and a Tokina 21/3.8, and an Ozunon (Canon FD mount) zoom that's f/3.8-5.2, and a Vivitar (Kiron) zoom that's f/3.8. Whereas the FA50/1.4 is often measured at f/1.5. I suspect lensmakers like to get that number as low as possible, just like prices are often marked as $0.99 rather than $1 because it's good psychology.

QuoteQuote:
This lens has the markings of being marketed by a company called Focal.
Focal was (is?) K-Mart's brand name for photo gear, with many of the same suppliers as Sears, Pennys, Vivitar, etc. The Focal primes I've use have been quite competent. Hmmm, Sears now owns K-Mart, but I don't think either sell store-badged cameras or lenses anymore.
09-02-2010, 12:41 AM   #15
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Read the Inquiring Minds Want to Know section, at the bottom of Features and Operation of the Ka Mount . Looking at the chart, you can see that there isn't a way to cover all possibilities with the pins. Newer lenses with the data pin don't have this limitation.


Thank you
Russell
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