Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-10-2016, 02:11 PM   #1
Forum Member
rbelyell's Avatar

Join Date: Mar 2016
Posts: 95
Setting problem with adapted lenses

hi

i am pretty new to pentax, having my ks2 about a month or two. i have a bunch of legacy glass, including for the old kodak retina series. i have a dkl>pk adapter and had been shooting the 50/1.8 in Tav mode, so that i could adjust the SS whilst the camera set the iso and i set the aperture manually. ive done this lots on other cameras and there is no issue metering. the results i got back from the ks2 after a few shoots were fine, with it operating similarly to what i had come to expect from the other digicams ive used in this way.

for some reason when i tried today to shoot this lens i kept getting AV (aperture priority) setting showing up in my screen regardless of what setting i had on the dial. so Tv, Tav, Sv all showed up as Av on my screen, thus precluding me from setting the SS. moreover, while the M setting let me set the SS, the camera refused to meter, so i had no idea how my SS/iso manual settings were effecting exposure.

can anyone help me understand what happened here?

thank you very much in advance.

04-10-2016, 02:23 PM   #2
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 43,275
To be able to use Tv, Sv, or TAv mode the camera has to be able to control the aperture (so this is not an option with non A-type lenses). That's why the camera is displaying all those modes as Av.

If you want the camera to meter properly, you have to use M mode with any manual lens that has an automatic diaphragm (i.e. manual K-mount lenses, or adapted lenses with an aperture coupler). Lenses with a manual diaphragm (such as M42 lenses) can also be used in Av mode, since the viewfinder darkens with the aperture ring, and stop-down metering is thus not necessary.

Here are the steps you need to follow in order to get everything to work
https://www.pentaxforums.com/forums/54-pentax-lens-articles/110657-how-use-me...k-x-k-7-a.html

In a nutshell, you need to make the following settings changes:
-customize the green button to control Tv shift in M mode
-allow the aperture ring to be used in the custom function menu

When shooting:
-select M mode
-press the green button just before taking each photo, in order to get the camera to set the shutter speed

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com's high server and development costs are user-supported. You can help cover those costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

04-10-2016, 02:26 PM   #3
Pentaxian




Join Date: Oct 2011
Location: Savannah, GA
Posts: 5,002
With manual lenses you've essentially only got two modes -- Av and M. Anything but M with act same as Av. With Pentax K manual lenses -- no contacts -- you've only got M mode as there is no way to stop down the lens in any other mode, but for adapted mounts you can use Av (with somewhat less accurate metering, according to some) and stop down yourself. In Av you should be able to use fixed ISO or auto ISO (I think), but you can only set the shutter speed in (M)anual mode. If you thought you were doing that before, you were just mistaken. (Maybe you were moving Ev comp.)

Here is the nitty-gritty:

https://www.pentaxforums.com/forums/54-pentax-lens-articles/110657-how-use-me...k-x-k-7-a.html

Last edited by vonBaloney; 04-10-2016 at 02:33 PM.
04-10-2016, 02:29 PM   #4
Pentaxian
Not a Number's Avatar

Join Date: Mar 2012
Location: Venice, CA
Posts: 4,263
With Pentax DSLRs lenses without an "A" pin should only shoot in M and default to Av mode even when set to Sv, TAv, P or Tv. I could not explain how you were able to shoot TAv mode before

04-10-2016, 02:39 PM   #5
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 43,275
QuoteOriginally posted by Not a Number Quote
I could not explain how you were able to shoot TAv mode before
Possibly because M with auto-ISO is displayed at TAv.

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com's high server and development costs are user-supported. You can help cover those costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

04-10-2016, 03:06 PM   #6
Forum Member
rbelyell's Avatar

Join Date: Mar 2016
Posts: 95
Original Poster
thank you all. i read the instructions on metering you provided and believe i understand them. may i ask for two further clarifications: if i do understand it correctly with non pentax adapted lenses there is no way for me to manually set the SS, manually set the aperture, and have the camera set the iso? closely related, there is also no way for me to set the SS and aperture manually and have the camera tell me if i am under or over exposing?
thank you again
04-10-2016, 03:19 PM   #7
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,483
QuoteOriginally posted by Adam Quote
When shooting:
-select M mode
-press the green button just before taking each photo, in order to get the camera to set the shutter speed
Thanks, Adam for reliably stepping in on these non-A lens inquiries with the basic instructions and the pertinent sticky. In reference to the second point in the text quoted, I have found it useful in my own personal practice to shoot M mode with my K-mount lenses the same as I do with my stop-down metered film cameras (Pentax Spotmatic, Ricoh Singlex TLS, and others). Back in the day, we did not meter between shots. Instead, we metered once, set the exposure (EC in those days was done manually) and did not meter again unless the light or subject changed. Doing so enabled us to work quickly and concentrate on composition and focus.

In short, real-time subject evaluation is seldom needed as long as the light and its orientation to the subject stays about the same. When I shoot with my non-metered cameras, there is seldom a need to evaluate exposure between shots for a particular sequence of shots. An interesting aside is that many cameras actively made it difficult to do otherwise. For example, my Spotmatic II automatically opens the aperture and shuts the meter off when the exposure button is pushed. To re-meter requires a clumsy up-motion on the meter switch.

The flow with adapted lenses is a little more complex due to inconsistencies with how recent model cameras behave with lenses lacking conductive bases. The most direct approach is to shoot in Av mode and use the A/M switch on the side of the lens to stop down prior to exposure. With this technique, metering takes care of itself. For lenses lacking the A/M switch or other preset mechanism (fully manual aperture) the user must count click stops to reach the desired aperture before making the exposure.

One additional caution is in regards to auto-ISO. I generally recommend that the feature be turned off when doing stop-down metering to remove ambiguity as to how an aperture change will affect shutter speed. On my K-3 in Av mode with an adapted lens mounted, auto-ISO results in the ISO setting ramping in preference to the shutter speed in moderate to dim light...or not...


Steve

Last edited by stevebrot; 04-10-2016 at 03:35 PM.
04-10-2016, 03:30 PM   #8
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,483
QuoteOriginally posted by rbelyell Quote
thank you all. i read the instructions on metering you provided and believe i understand them. may i ask for two further clarifications: if i do understand it correctly with non pentax adapted lenses there is no way for me to manually set the SS, manually set the aperture, and have the camera set the iso? closely related, there is also no way for me to set the SS and aperture manually and have the camera tell me if i am under or over exposing?
thank you again
Whether the lens is Pentax or Asahi brand makes no difference. The only real discriminating factors for stop-down metering with vintage lenses are:
  • K-mount with aperture actuator, Y/N
  • Conductive base, Y/N
Lenses without an aperture actuator that couples to the body must be manually stopped down to meter and for exposure. Lenses lacking a conductive base may work using the green button in M mode on some bodies, but Av mode is sure to work assuming that the lens has a stop-down switch or fully manual aperture mechanism.

In regards to being able to set aperture on lens and shutter on camera and have the camera choose ISO...To the best of my knowledge, no current model Pentax dSLR supports that feature. I believe that the same applies to all Pentax dSLRs. The reason is that the body must "know" the set aperture AND the set shutter speed in order to automatically adjust the ISO.* If the aperture is set using the ring on the lens, but the body knows nothing.

Edit: I thought a little more about this and what I wrote is only true because current Pentax cameras disallow auto-ISO in M-mode as a general rule. I do not recall the behavior in older model bodies.


Steve


Last edited by stevebrot; 04-10-2016 at 04:09 PM.
04-10-2016, 03:37 PM   #9
Forum Member
rbelyell's Avatar

Join Date: Mar 2016
Posts: 95
Original Poster
thank you steve, much appreciated. i love my ks2 and the native lenses i am using. i must say that ive shot digital with canon, nikon, sony, fuji, oly, sigma and panny and there has always been a way for the camera to meter my adapted lenses, at the very least by some indication that whatever combination of my manually set aperture/ SS/ iso i chose would yield an under or over exposed image. while most were mirrorless cameras, the canon, nikon and sigma were all dslrs with mirrors and optical finders. well, thats disappointing and too bad for me!

again, thank you to everyone for their very timely assistance!
04-10-2016, 03:48 PM   #10
Pentaxian




Join Date: Nov 2014
Location: South Bend, IN, USA
Photos: Gallery | Albums
Posts: 2,983
QuoteOriginally posted by stevebrot Quote
Whether the lens is Pentax or Asahi brand makes no difference. The only real discriminating factors for stop-down metering with vintage lenses are:
  • K-mount with aperture actuator, Y/N
  • Conductive base, Y/N
At the risk of creating confusion {but perhaps necessary since the OP is already using an adapter, which apparently presents a K-mount}, we should perhaps state this in terms of the mount.
  • K-mount {also sometimes called PK-mount}
  • KA-mount {also sometimes called PKA-mount?}
I think in these terms partly because I'm a {retired} software engineer, where we use the term "interface" where cameras use "mount", and partly because I have several Tamron AdaptAll lenses, some presenting a K-mount and some presenting a KA-mount.
04-10-2016, 03:52 PM   #11
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,483
QuoteOriginally posted by rbelyell Quote
thank you steve, much appreciated. i love my ks2 and the native lenses i am using. i must say that ive shot digital with canon, nikon, sony, fuji, oly, sigma and panny and there has always been a way for the camera to meter my adapted lenses
I edited my last post. See my correction.

As for an indication of over/under, EC is available in both Av and M modes. In addition, a viewfinder EV scale is available in M mode on flaghip models by using the optical preview feature.* I will have to research your K-S2 to see if it supports similar.


Steve

* Only visible if the optical viewfinder level feature is turned OFF.

Last edited by stevebrot; 04-10-2016 at 04:01 PM.
04-10-2016, 04:07 PM   #12
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,483
QuoteOriginally posted by reh321 Quote
At the risk of creating confusion {but perhaps necessary since the OP is already using an adapter, which apparently presents a K-mount}, we should perhaps state this in terms of the mount.
  • K-mount {also sometimes called PK-mount}
  • KA-mount {also sometimes called PKA-mount?}
I think in these terms partly because I'm a {retired} software engineer, where we use the term "interface" where cameras use "mount", and partly because I have several Tamron AdaptAll lenses, some presenting a K-mount and some presenting a KA-mount.
My comment was specifically in regard to stop-down metering. Where things get complicated is where a native K-mount lens lacks an aperture actuator lever. A good example is the Pentax-K 28/3.5 Shift or various T-mount lenses having pre-set or fully manual apertures. There are multiple permutations for actuator vs. none vs. conductive base vs. various Pentax body models.


Steve
04-10-2016, 04:45 PM   #13
Forum Member
rbelyell's Avatar

Join Date: Mar 2016
Posts: 95
Original Poster
QuoteOriginally posted by stevebrot Quote
I edited my last post. See my correction.

As for an indication of over/under, EC is available in both Av and M modes. In addition, a viewfinder EV scale is available in M mode on flaghip models by using the optical preview feature.* I will have to research your K-S2 to see if it supports similar.


Steve

* Only visible if the optical viewfinder level feature is turned OFF.
thanks steve. i do not believe it is available on the ks2. the EC is visible in Live View, but doesnt move to reflect changes in aperture, SS or iso, so for my purpose, its presence seems not useful.

Last edited by rbelyell; 04-10-2016 at 04:52 PM.
04-10-2016, 05:53 PM   #14
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,483
QuoteOriginally posted by rbelyell Quote
thanks steve. i do not believe it is available on the ks2. the EC is visible in Live View, but doesnt move to reflect changes in aperture, SS or iso, so for my purpose, its presence seems not useful.
I did the research and it is possible that the EV scale showing over/under might be visible in the optical viewfinder in M mode if you map the RAW/Fx button to Optical Preview and have a conductive base lens mounted. Unfortunately, I believe that most DKL/K-mount adapters have anodized/painted mount surface.


Steve
04-10-2016, 05:59 PM - 1 Like   #15
Forum Member
rbelyell's Avatar

Join Date: Mar 2016
Posts: 95
Original Poster
QuoteOriginally posted by stevebrot Quote
I did the research and it is possible that the EV scale showing over/under might be visible in the optical viewfinder in M mode if you map the RAW/Fx button to Optical Preview and have a conductive base lens mounted. Unfortunately, I believe that most DKL/K-mount adapters have anodized/painted mount surface.


Steve
wow steve THAT WORKED! if i set the RAW button as you suggested and press it in M mode, i can manually set the SS and/or aperture to whatever i want and i see the effect on the EV bar! excellent! that is really a big deal for me. thank you so much! i hope i can repay the favor sometime.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
aperture, av, camera, dslr, photography, ss, tav
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Still no external manual flash triggering with adapted lenses? Doundounba Pentax Q 19 07-29-2014 12:01 PM
New Q with Adapted Lenses! tjdean01 Welcomes and Introductions 5 05-18-2014 01:21 AM
External flash with adapted lenses baro-nite Pentax Q 24 12-20-2012 07:38 PM
Problem setting exposure with K-7 sceadgugenga Pentax DSLR Discussion 7 10-14-2010 02:33 AM



All times are GMT -7. The time now is 08:02 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top