Getting f------ with certain lenses

noleysdad · 05-15-2008, 06:18 AM

I know I have seen this before but I can't remember the remedy. When I use certain lenses I get f------ in the top screen. These lenses are pentax lenses or at least fit pentax.......Help!

Brian

bnishanth · 05-15-2008, 06:24 AM

The title of this article is very misleading..

Can you give us more information on the lens ? Is it a 'M' lens ?

If the Aperture ring on the lens cannot be set to 'A' then the camera fails to determine the aperture setting and flashes on the LCD. However this does not prevent you from exposing a shot as you can set the appropriate shutter (in Hyper-Manual mode) by clicking the green button.

Cheers
Nish

smokey · 05-15-2008, 06:26 AM

Do the lenses have the 'A' setting on the aperture ring? If not, you need to change your camera settings. Using aperture ring to Permitted in the custom settings menu.
If the lens does, then make sure it is set on 'A'.

Peacekeeper · 05-15-2008, 06:29 AM

Dirty lens/camera contacts can make the Av display -- as well

séamuis · 05-15-2008, 06:31 AM

any lens that doesn't have the 'A' setting on the aperture ring will do that because the lens is not communicating with the camera. essentially any lens before the A series will do that unless you have a newer lens and don't select the 'A'. there are also plenty of 3rd part lenses that have the 'A' setting as well. so in pentax land that means M,K & m42 lenses will do this.

The KA mount is derived from the original K mount. It allows the lens' aperture to be set by the body, and thus permits shutter priority and program auto exposure modes. It was introduced in 1983, and is supported by A-series and P-series bodies; Pentax lenses that support it are marked 'SMC Pentax-A'. It is completely backward-compatible with the original K mount.
The aperture on the lens is set from the body by the same stop-down lever found on the original K mount, but on KA lenses this lever is proportional to the area of the aperture opening, rather than the diameter as on previous lenses. This allows the body to easily set a specific aperture, since the relationship to F stops is linear. The lenses add an 'A' setting on the aperture dial, which gives the body control of the aperture. Other, numeric settings are used for manual aperture modes—aperture priority and full manual mode.
Six electrical contacts are added to the bayonet ring. One is slightly recessed and allows the lens to indicate whether the aperture ring is set at 'A' or not. If it is, a pin on the lens extends slightly and makes contact, while if the lens is at any other setting the pin is retracted and does not make contact. The other five contacts are used to encode the lens' aperture range. Each contact on the lens is either conducting or non-conducting, providing a binary 1 or 0, respectively. Two contacts encode the lens' minimum aperture—f/16, f/22, f/32 or f/45; although no Pentax K-mount lens has ever had an f/16 minimum aperture, OEM lenses often have. The other three contacts encode the lens' maximum aperture; their meaning is dependent on the minimum aperture indicated by the lens.

noleysdad · 05-15-2008, 08:01 AM

one lens is a m42 with an adapter, the other is a 50mm I took off of my Pentax ME. Both do not have an A on the aperture ring. Contacts are clean....
Is it possible to get these lenses to work on my K10? How? mainly shoot manual mode.

séamuis · 05-15-2008, 08:08 AM

is it an M 50mm? I would assume so. either way with the K10 you first have to make sure and 'allow aperture ring' in the menu. (check the manual if you need to know how to do that)

mount the lens
select the M 'manual' mode
select desired aperture
compose and frame your shot
push the 'green button'
the camera will then stop down the lens, meter the light and select the appropriate shutter speed for proper exposure
take the picture.

the same goes for the m42 lens except you can use an m42 in Av mode to simplify things. M, an K series bayonet lenses ( or any A series or later not in 'A' mode) however will not get proper exposure on your K10 (except at widest aperture) due to the 'crippled' mount.

Magnus W · 05-15-2008, 08:12 AM

Originally posted by noleysdad

one lens is a m42 with an adapter, the other is a 50mm I took off of my Pentax ME. Both do not have an A on the aperture ring. Contacts are clean....
Is it possible to get these lenses to work on my K10? How? mainly shoot manual mode.

If they don't have an "A", the lens can't tell the body what aperture it is set to.
You get the "f----" on the display. You have to measure stopped down, with the green button or AE-L.

-- MW

noleysdad · 05-15-2008, 08:14 AM

Thank you all for you input........its much appreciated.

B

bnishanth · 05-15-2008, 09:43 AM

Originally posted by séamuis

mount the lens
select the M 'manual' mode
select desired aperture
compose and frame your shot
push the 'green button'
the camera will then stop down the lens, meter the light and select the appropriate shutter speed for proper exposure
take the picture.

One more thing...
Change 'Use Aperture Ring' to permitted in Custom menu to use the Green Button if you are not able to do the above..

Cheers
Nish

séamuis · 05-15-2008, 09:52 AM

ahem, I covered that

Quote:

either way with the K10 you first have to make sure and 'allow aperture ring' in the menu.

noleysdad · 05-16-2008, 05:44 AM

Thanks alot.........got it figured out.

B

bnishanth · 05-16-2008, 12:25 PM

Sorry séamuis, I missed that....

05-15-2008, 06:18 AM	#1
noleysdad Inactive Account Join Date: Sep 2007 Location: Menifee, CA Photos: Gallery Posts: 8	Getting f------ with certain lenses I know I have seen this before but I can't remember the remedy. When I use certain lenses I get f------ in the top screen. These lenses are pentax lenses or at least fit pentax.......Help! Brian

05-16-2008, 12:25 PM	#13
bnishanth Senior Member Join Date: May 2008 Location: Sydney Photos: Gallery Posts: 223	Sorry..!! Sorry séamuis, I missed that....

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05-15-2008, 06:24 AM	#2
bnishanth Senior Member Join Date: May 2008 Location: Sydney Photos: Gallery Posts: 223	The title of this article is very misleading.. Can you give us more information on the lens ? Is it a 'M' lens ? If the Aperture ring on the lens cannot be set to 'A' then the camera fails to determine the aperture setting and flashes on the LCD. However this does not prevent you from exposing a shot as you can set the appropriate shutter (in Hyper-Manual mode) by clicking the green button. Cheers Nish

05-15-2008, 06:26 AM	#3
smokey Forum Member Join Date: Sep 2007 Location: Salina, KS Posts: 92	Do the lenses have the 'A' setting on the aperture ring? If not, you need to change your camera settings. Using aperture ring to Permitted in the custom settings menu. If the lens does, then make sure it is set on 'A'.

05-15-2008, 06:29 AM	#4
Peacekeeper Senior Member Join Date: Jul 2007 Location: Back at work :( Photos: Gallery Posts: 168	Dirty lens/camera contacts can make the Av display -- as well

05-15-2008, 06:31 AM	#5
séamuis Banned Join Date: Oct 2007 Location: Savannah, U.S./Baguio City, P.H. Posts: 5,979	any lens that doesn't have the 'A' setting on the aperture ring will do that because the lens is not communicating with the camera. essentially any lens before the A series will do that unless you have a newer lens and don't select the 'A'. there are also plenty of 3rd part lenses that have the 'A' setting as well. so in pentax land that means M,K & m42 lenses will do this. The KA mount is derived from the original K mount. It allows the lens' aperture to be set by the body, and thus permits shutter priority and program auto exposure modes. It was introduced in 1983, and is supported by A-series and P-series bodies; Pentax lenses that support it are marked 'SMC Pentax-A'. It is completely backward-compatible with the original K mount. The aperture on the lens is set from the body by the same stop-down lever found on the original K mount, but on KA lenses this lever is proportional to the area of the aperture opening, rather than the diameter as on previous lenses. This allows the body to easily set a specific aperture, since the relationship to F stops is linear. The lenses add an 'A' setting on the aperture dial, which gives the body control of the aperture. Other, numeric settings are used for manual aperture modes—aperture priority and full manual mode. Six electrical contacts are added to the bayonet ring. One is slightly recessed and allows the lens to indicate whether the aperture ring is set at 'A' or not. If it is, a pin on the lens extends slightly and makes contact, while if the lens is at any other setting the pin is retracted and does not make contact. The other five contacts are used to encode the lens' aperture range. Each contact on the lens is either conducting or non-conducting, providing a binary 1 or 0, respectively. Two contacts encode the lens' minimum aperture—f/16, f/22, f/32 or f/45; although no Pentax K-mount lens has ever had an f/16 minimum aperture, OEM lenses often have. The other three contacts encode the lens' maximum aperture; their meaning is dependent on the minimum aperture indicated by the lens.

05-15-2008, 08:01 AM	#6
noleysdad Inactive Account Join Date: Sep 2007 Location: Menifee, CA Photos: Gallery Posts: 8 Original Poster	one lens is a m42 with an adapter, the other is a 50mm I took off of my Pentax ME. Both do not have an A on the aperture ring. Contacts are clean.... Is it possible to get these lenses to work on my K10? How? mainly shoot manual mode.

05-15-2008, 08:08 AM	#7
séamuis Banned Join Date: Oct 2007 Location: Savannah, U.S./Baguio City, P.H. Posts: 5,979	is it an M 50mm? I would assume so. either way with the K10 you first have to make sure and 'allow aperture ring' in the menu. (check the manual if you need to know how to do that) mount the lens select the M 'manual' mode select desired aperture compose and frame your shot push the 'green button' the camera will then stop down the lens, meter the light and select the appropriate shutter speed for proper exposure take the picture. the same goes for the m42 lens except you can use an m42 in Av mode to simplify things. M, an K series bayonet lenses ( or any A series or later not in 'A' mode) however will not get proper exposure on your K10 (except at widest aperture) due to the 'crippled' mount.

05-15-2008, 08:12 AM	#8
Magnus W Junior Member Join Date: May 2007 Location: Uppsala, Sweden Photos: Gallery Posts: 46	Originally posted by noleysdad one lens is a m42 with an adapter, the other is a 50mm I took off of my Pentax ME. Both do not have an A on the aperture ring. Contacts are clean.... Is it possible to get these lenses to work on my K10? How? mainly shoot manual mode. If they don't have an "A", the lens can't tell the body what aperture it is set to. You get the "f----" on the display. You have to measure stopped down, with the green button or AE-L. -- MW

05-15-2008, 08:14 AM	#9
noleysdad Inactive Account Join Date: Sep 2007 Location: Menifee, CA Photos: Gallery Posts: 8 Original Poster	Thank you all for you input........its much appreciated. B

05-15-2008, 09:43 AM	#10
bnishanth Senior Member Join Date: May 2008 Location: Sydney Photos: Gallery Posts: 223	Originally posted by séamuis mount the lens select the M 'manual' mode select desired aperture compose and frame your shot push the 'green button' the camera will then stop down the lens, meter the light and select the appropriate shutter speed for proper exposure take the picture. One more thing... Change 'Use Aperture Ring' to permitted in Custom menu to use the Green Button if you are not able to do the above.. Cheers Nish

05-15-2008, 09:52 AM	#11
séamuis Banned Join Date: Oct 2007 Location: Savannah, U.S./Baguio City, P.H. Posts: 5,979	ahem, I covered that Quote: either way with the K10 you first have to make sure and 'allow aperture ring' in the menu.

05-16-2008, 05:44 AM	#12
noleysdad Inactive Account Join Date: Sep 2007 Location: Menifee, CA Photos: Gallery Posts: 8 Original Poster	Thanks alot.........got it figured out. B