Stop Down Metering With The Green Button: Wrong Exposure Recomendations

Raylon · 10-06-2010, 06:15 AM

Originally posted by violini

Pentax ME, M50mm/1.7, 135mm/3.5, K-x, K-7, DA15mm. DFA 100mm WR Macro.

Holy white balance batman! It's way off!

But yea my K200 was never that good. I simply used the green button to get a starting point and worked from there.

Obs · 10-07-2010, 02:35 PM

OK, so here's a photo I took, just outside my apartment. I just ordered a book called "Understanding exposure: how to shoot great photographs with a film or digital camera", by Bryan Peterson, to better my understanding of SLR photography. Thanks again for the help guys.

Nowhere Matt · 10-08-2010, 06:00 AM

Originally posted by boriscleto

You need to stop down or lower the ISO. The K-x defaults to 0.3 when there is too much light.

That is good to know but most times when I point my lens to the sky and get 0.3 setting it is because I have forgotten to remove the lens cap.

violini · 10-10-2010, 05:11 PM

"Fogel70:

If using Av-mode a K-mount lens with aperture ring it has to be set on A-position for the camera to stop down the lens.
All pre-A lenses will only be used with widest aperture in Av-mode, so for controlling aperture you need to use manual mode."

On Pentax-M 135mm/3.5, the aperture is controlled by the aperture ring, not the camera body. Use mode M for M50mm/1.7.

pschlute · 10-10-2010, 05:36 PM

Originally posted by violini

"Fogel70:

If using Av-mode a K-mount lens with aperture ring it has to be set on A-position for the camera to stop down the lens.
All pre-A lenses will only be used with widest aperture in Av-mode, so for controlling aperture you need to use manual mode."

On Pentax-M 135mm/3.5, the aperture is controlled by the aperture ring, not the camera body. Use mode M for M50mm/1.7.

Yes we know the aperture is controlled by the lens. The point he was making is that in Av mode any M lens will shoot only at widest aperture irrespective of where you set the aperture ring. You must use Manual mode to allow your aperture selection to work.

violini · 10-11-2010, 07:40 AM

OK, it works on mode M. If one does not mind shooting at wide open aperture, Av mode is more convenient to get a correct exposure.

aleonx3 · 10-11-2010, 08:31 AM

Originally posted by violini

On my M135mm, the aperture blades move following the setting on the ring, no DOF preview or stop-down. That's why it works on Av mode.

Both Forgel70 and pschlute were right, any other mode except M mode allows you to change the aperture, otherwise, you are shooting with wide-open aperture. One simple test is to turn the aperture ring to any value and press the green button once, does the shutter speed get changed? Nope.... it stays the same.

Also, with M lens, the metering is changed to center-weigh, so you have to adjust accordingly if you are still thinking matrix metering.

violini · 10-12-2010, 09:09 AM

One experiment I'm going to do is to cut or remove the aperture control lever at the base of the lens. Then I can use Av mode without worrying about metering. The drawback is the viewfinder may become too dark for small aperture.

I think the camera firm/soft ware should be revised to allow setting of aperture value when M series lenses are used. (instead of blank F--)

Nowhere Matt · 10-12-2010, 10:30 AM

Originally posted by violini

One experiment I'm going to do is to cut or remove the aperture control lever at the base of the lens. Then I can use Av mode without worrying about metering. The drawback is the viewfinder may become too dark for small aperture.

I think the camera firm/soft ware should be revised to allow setting of aperture value when M series lenses are used. (instead of blank F--)

I am at least the second owner of a Vivitar 80-200mm f4.5 that has this type of modification. I as well as a few others can tell you that the lens will perform exactly as you imagine in Av and other program modes somewhat satisfyingly. It eliminates using the green button but does of course darken the scene as you look through the viewfinder as you close the aperture manually.
If you would like, (and live in America) send me a message and we could talk about conditions of me giving you this modified Vivitar lens to play with to decide if you want to mod your own lens.

Obs · 10-13-2010, 03:46 PM

I think I may just purchase Pentax-A lenses from this point on, and shoot in Av mode. I find Pentax-M lenses just too difficult to work with; stopping down with the green button just doesn't do it for me. I just purchased a Pentax-A 50mm 1.7, so hopefully all I'll have to worry about is manually adjusting focus.

**Lowell Goudge** · 10-13-2010, 05:42 PM

Originally posted by Obs

I think I may just purchase Pentax-A lenses from this point on, and shoot in Av mode. I find Pentax-M lenses just too difficult to work with; stopping down with the green button just doesn't do it for me. I just purchased a Pentax-A 50mm 1.7, so hopefully all I'll have to worry about is manually adjusting focus.

Just get a k10 or K20 with an *istD screen and make it an MF body only. It'll meter just fine

Obs · 10-13-2010, 07:19 PM

Originally posted by Lowell Goudge

Just get a k10 or K20 with an *istD screen and make it an MF body only. It'll meter just fine

The only gripe I have with the k-x is the fact that when I stop down meter dark objects with my Pentax-M 50mm 1.4 using the +/- button, the recommened shutter speed is usually some ridicoulous shutter speed like 0.8", or 1.6", I'm talking dark objects even in daylight!

I don't know. What could be the issue?

Obs · 10-13-2010, 07:47 PM

After a couple of night shots with the k-x, I have come to the conclusion that metering using stop down via the +/- button is useless. I guess I just save my money for a good DA lens. Can anyone recommend a thread

**boriscleto** · 10-13-2010, 08:02 PM

The pictures in this flickr set were all taken using stop down metering with the +- button. While the lighting isn't ideal I wouldn't say the exposures are useless.

50mm shootout - a set on Flickr

What metering mode are you using? Do you have the camera set to Center-weighted or Spot?

**Canada_Rockies** · 10-13-2010, 08:26 PM

Originally posted by boriscleto

The pictures in this flickr set were all taken using stop down metering with the +- button. While the lighting isn't ideal I wouldn't say the exposures are useless.

50mm shootout - a set on Flickr

What metering mode are you using? Do you have the camera set to Center-weighted or Spot?

And this flickr set shows my M 400/5.6 that convinced me to install an LL60 (*istD) screen in my K10d.
K10d + Smcp-m 400/5.6 - a set on Flickr

10-11-2010, 07:40 AM	#21
violini Veteran Member Join Date: Aug 2010 Location: Winnipeg MB Photos: Gallery Posts: 350	OK, it works on mode M. If one does not mind shooting at wide open aperture, Av mode is more convenient to get a correct exposure. Last edited by violini; 10-11-2010 at 12:34 PM.

10-12-2010, 09:09 AM	#23
violini Veteran Member Join Date: Aug 2010 Location: Winnipeg MB Photos: Gallery Posts: 350	One experiment I'm going to do is to cut or remove the aperture control lever at the base of the lens. Then I can use Av mode without worrying about metering. The drawback is the viewfinder may become too dark for small aperture. I think the camera firm/soft ware should be revised to allow setting of aperture value when M series lenses are used. (instead of blank F--) Last edited by violini; 10-12-2010 at 09:35 AM.

10-13-2010, 07:19 PM	#27
Obs Inactive Account Join Date: Sep 2010 Location: New York City Posts: 8 Original Poster	Originally posted by Lowell Goudge Just get a k10 or K20 with an istD screen and make it an MF body only. It'll meter just fine The only gripe I have with the k-x is the fact that when I stop down meter dark objects with my Pentax-M 50mm 1.4 using the +/- button, the recommened shutter speed is usually some ridicoulous shutter speed like 0.8", or 1.6", I'm talking dark objects even in daylight! I don't know. What could be the issue? Last edited by Obs; 10-13-2010 at 07:26 PM.*

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10-06-2010, 06:15 AM	#16
Raylon Guest	Originally posted by violini Pentax ME, M50mm/1.7, 135mm/3.5, K-x, K-7, DA15mm. DFA 100mm WR Macro. Holy white balance batman! It's way off! But yea my K200 was never that good. I simply used the green button to get a starting point and worked from there.

10-07-2010, 02:35 PM	#17
Obs Inactive Account Join Date: Sep 2010 Location: New York City Posts: 8 Original Poster	OK, so here's a photo I took, just outside my apartment. I just ordered a book called "Understanding exposure: how to shoot great photographs with a film or digital camera", by Bryan Peterson, to better my understanding of SLR photography. Thanks again for the help guys.

10-08-2010, 06:00 AM	#18
Nowhere Matt Veteran Member Join Date: Nov 2007 Location: Nowhere Land Photos: Gallery \| Albums Posts: 2,362	Originally posted by boriscleto You need to stop down or lower the ISO. The K-x defaults to 0.3 when there is too much light. That is good to know but most times when I point my lens to the sky and get 0.3 setting it is because I have forgotten to remove the lens cap.

10-10-2010, 05:11 PM	#19
violini Veteran Member Join Date: Aug 2010 Location: Winnipeg MB Photos: Gallery Posts: 350	"Fogel70: If using Av-mode a K-mount lens with aperture ring it has to be set on A-position for the camera to stop down the lens. All pre-A lenses will only be used with widest aperture in Av-mode, so for controlling aperture you need to use manual mode." On Pentax-M 135mm/3.5, the aperture is controlled by the aperture ring, not the camera body. Use mode M for M50mm/1.7.

10-10-2010, 05:36 PM	#20
pschlute Moderator Loyal Site Supporter Join Date: Mar 2007 Location: Surrey, UK Photos: Gallery Posts: 8,211	Originally posted by violini "Fogel70: If using Av-mode a K-mount lens with aperture ring it has to be set on A-position for the camera to stop down the lens. All pre-A lenses will only be used with widest aperture in Av-mode, so for controlling aperture you need to use manual mode." On Pentax-M 135mm/3.5, the aperture is controlled by the aperture ring, not the camera body. Use mode M for M50mm/1.7. Yes we know the aperture is controlled by the lens. The point he was making is that in Av mode any M lens will shoot only at widest aperture irrespective of where you set the aperture ring. You must use Manual mode to allow your aperture selection to work.

10-11-2010, 08:31 AM	#22
aleonx3 Veteran Member Join Date: Jul 2007 Location: Brampton, Ontario Photos: Gallery \| Albums Posts: 3,996	Originally posted by violini On my M135mm, the aperture blades move following the setting on the ring, no DOF preview or stop-down. That's why it works on Av mode. Both Forgel70 and pschlute were right, any other mode except M mode allows you to change the aperture, otherwise, you are shooting with wide-open aperture. One simple test is to turn the aperture ring to any value and press the green button once, does the shutter speed get changed? Nope.... it stays the same. Also, with M lens, the metering is changed to center-weigh, so you have to adjust accordingly if you are still thinking matrix metering.

10-12-2010, 10:30 AM	#24
Nowhere Matt Veteran Member Join Date: Nov 2007 Location: Nowhere Land Photos: Gallery \| Albums Posts: 2,362	Originally posted by violini One experiment I'm going to do is to cut or remove the aperture control lever at the base of the lens. Then I can use Av mode without worrying about metering. The drawback is the viewfinder may become too dark for small aperture. I think the camera firm/soft ware should be revised to allow setting of aperture value when M series lenses are used. (instead of blank F--) I am at least the second owner of a Vivitar 80-200mm f4.5 that has this type of modification. I as well as a few others can tell you that the lens will perform exactly as you imagine in Av and other program modes somewhat satisfyingly. It eliminates using the green button but does of course darken the scene as you look through the viewfinder as you close the aperture manually. If you would like, (and live in America) send me a message and we could talk about conditions of me giving you this modified Vivitar lens to play with to decide if you want to mod your own lens.

10-13-2010, 03:46 PM	#25
Obs Inactive Account Join Date: Sep 2010 Location: New York City Posts: 8 Original Poster	I think I may just purchase Pentax-A lenses from this point on, and shoot in Av mode. I find Pentax-M lenses just too difficult to work with; stopping down with the green button just doesn't do it for me. I just purchased a Pentax-A 50mm 1.7, so hopefully all I'll have to worry about is manually adjusting focus.

10-13-2010, 05:42 PM	#26
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,891	Originally posted by Obs I think I may just purchase Pentax-A lenses from this point on, and shoot in Av mode. I find Pentax-M lenses just too difficult to work with; stopping down with the green button just doesn't do it for me. I just purchased a Pentax-A 50mm 1.7, so hopefully all I'll have to worry about is manually adjusting focus. Just get a k10 or K20 with an *istD screen and make it an MF body only. It'll meter just fine

10-13-2010, 07:47 PM	#28
Obs Inactive Account Join Date: Sep 2010 Location: New York City Posts: 8 Original Poster	After a couple of night shots with the k-x, I have come to the conclusion that metering using stop down via the +/- button is useless. I guess I just save my money for a good DA lens. Can anyone recommend a thread

10-13-2010, 08:02 PM	#29
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	The pictures in this flickr set were all taken using stop down metering with the +- button. While the lighting isn't ideal I wouldn't say the exposures are useless. 50mm shootout - a set on Flickr What metering mode are you using? Do you have the camera set to Center-weighted or Spot?

10-13-2010, 08:26 PM	#30
Canada_Rockies Loyal Site Supporter Join Date: Nov 2007 Location: Sparwood, BC, Canada Photos: Gallery \| Albums Posts: 12,385	Originally posted by boriscleto The pictures in this flickr set were all taken using stop down metering with the +- button. While the lighting isn't ideal I wouldn't say the exposures are useless. 50mm shootout - a set on Flickr What metering mode are you using? Do you have the camera set to Center-weighted or Spot? And this flickr set shows my M 400/5.6 that convinced me to install an LL60 (*istD) screen in my K10d. K10d + Smcp-m 400/5.6 - a set on Flickr