Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-22-2009, 08:45 AM   #1
Inactive Account




Join Date: May 2007
Posts: 221
SMC 500mm f4.5 soft focus issues :(

hi,

i have a 500mm f4.5 I have it on a tripod with a TV of at least 500/sec; the SR is off and my aperture is f8; but i am still getting soft focus when downloaded to desktop, even though I am getting focus indicator when shooting

??

any advice? is this just par for this lens? or am i missing something?

i am using a k10 now going to check with k20

i switched to the k20 and the menu asked for the focal length i put 500mm; however the k10 did not ask????

i turn ed off the k20 aND then back on but it did not ask for manual focal length ;hmmm?????


thanks


Last edited by rdrum76; 03-22-2009 at 09:01 AM.
03-22-2009, 09:19 AM   #2
Veteran Member
8540tomg's Avatar

Join Date: Feb 2008
Location: Waterloo, Ontario
Photos: Gallery
Posts: 4,461
QuoteOriginally posted by rdrum76 Quote
hi,

i have a 500mm f4.5 I have it on a tripod with a TV of at least 500/sec; the SR is off and my aperture is f8; but i am still getting soft focus when downloaded to desktop, even though I am getting focus indicator when shooting

??

any advice? is this just par for this lens? or am i missing something?

i am using a k10 now going to check with k20

i switched to the k20 and the menu asked for the focal length i put 500mm; however the k10 did not ask????

i turn ed off the k20 aND then back on but it did not ask for manual focal length ;hmmm?????


thanks
I have noticed on the K10 when shake reduction is turned off that you are not prompted for lens length. With a 500mm lens I suspect depth of field will be very shallow even at f 8. I would recommend trying something in the f 11 - f 22 range. I have had a lot more success with my M 400mm in this f stop range. Even if the camera confirms focus this is not always accurate.

What sort of focusing screen are you using? Until I got a KatzEye I found getting sharp focus with older lenses to be very difficult especially with longer telephoto lenses. The Katzeye screen has helped me a lot in this area. Even with the new screen I take multiple shots fine focusing all the time. This has improved the number of acceptable shots.

Tom

Last edited by 8540tomg; 03-22-2009 at 11:04 AM. Reason: typo
03-22-2009, 09:26 AM   #3
Veteran Member
philbaum's Avatar

Join Date: Oct 2007
Location: Port Townsend, Washington State, USA
Posts: 3,659
I don't know if you are already doing this, but to get the FL menu on power up, the K10D has to be in Manual exposure mode and the AF switch has to be in Manual as well (i think :-))

I don't have the 500 but i have an smc 400mm f5.6 lens, has a very long focus travel and is a bit tricky to focus. But you're saying that you haven't been able to hit it at all? That hasn't been my exp. with the smc 400mm
03-22-2009, 09:34 AM   #4
Inactive Account




Join Date: May 2007
Posts: 221
Original Poster
i actually have a magnifier on

i am trying f11 but not easy to focus; i heard the katz eye throws off your EV?

03-22-2009, 09:36 AM   #5
Loyal Site Supporter
Loyal Site Supporter
Canada_Rockies's Avatar

Join Date: Nov 2007
Location: Sparwood, BC, Canada
Photos: Gallery | Albums
Posts: 12,385
QuoteOriginally posted by philbaum Quote
I don't know if you are already doing this, but to get the FL menu on power up, the K10D has to be in Manual exposure mode and the AF switch has to be in Manual as well (i think :-))
The only factor for asking for the focal length is to have the shake reduction turned on.

I find this handy, even on the tripod, because the EXIF includes the shooting focal length based on this input. I turn on the SR, turn on the camera, and set the focal length, then set SR off. I have photos with EXIF data that says "550mm K/M Lens" which tells me when I look at the image in Lightroom that I was using my M 400 with the 1.4X-S converter, for example.
03-22-2009, 09:40 AM   #6
Inactive Account




Join Date: May 2007
Posts: 221
Original Poster
f11 should be good, right???

when would use try it use anything close to f4.5; i am guessing bright light and big thing
03-22-2009, 09:41 AM   #7
Inactive Account




Join Date: May 2007
Posts: 221
Original Poster
ty; i just learned that trick by accident

now i am opening up for focus then close down to an acceptable shutter speed while in green auto exposure

a little better

i need to get a friend to stand in the backyard instead of crazy moving birds and rabbits


Last edited by rdrum76; 03-22-2009 at 10:05 AM.
03-22-2009, 10:08 AM   #8
Senior Member
Mark2100's Avatar

Join Date: Dec 2007
Location: Oklahoma
Posts: 185
I have the Tak 500/4.5, and it tends to front focus with the af confirmation light by 8 or 9 inches. (tested on a wooden fence). Of course the coating on one the elements is half gone, so the lens isn't perfect. But I don't think that would affect the ff/bf issue. I would adjust the camera to fix it, but none of my other manual lenses behave this way.

Here's the pic... I had focus confirmation on the center picket. The one with the black spot on it.
Attached Images
View Picture EXIF
PENTAX K20D  Photo 
03-22-2009, 10:24 AM   #9
Inactive Account




Join Date: May 2007
Posts: 221
Original Poster
how would you adjust the focus on a k10, when it is set to mf? i do not think the k10 has af adjustment?
03-22-2009, 10:35 AM   #10
Site Supporter
Site Supporter
dadipentak's Avatar

Join Date: Jul 2008
Location: Baltimore, Maryland
Photos: Gallery
Posts: 11,590
I had this lens and it is a challenge. Stop down and don't rely on focus confirmation. My best results were with tripod & remote, taking multiple shots with fine focus gradations. And, right--the camera only cares about FL for SR purposes. Good thinking, Albert!
03-22-2009, 10:35 AM   #11
Senior Member
Mark2100's Avatar

Join Date: Dec 2007
Location: Oklahoma
Posts: 185
QuoteOriginally posted by rdrum76 Quote
how would you adjust the focus on a k10, when it is set to mf? i do not think the k10 has af adjustment?
I was using a k20d. You're right, the k10 doesn't have a focus adjustment. The downside of the focus adjustment on the k20 for manual lenses, is it's generic, and changes for all manual lenses.
With the Tak, I just focus a little past where I get confirmation. If you have a fence, you should try this test as well. I'm curious if your lens has the same issue as mine.
03-22-2009, 10:47 AM   #12
Site Supporter
Site Supporter




Join Date: Feb 2008
Location: MT
Photos: Gallery
Posts: 1,349
I'm betting the softness is "pilot error." Are you using a substantial tripod? Look through the viewfinder, can you see tiny movements? That will equal blur even though the focus indicator will show focus is OK. Tap the top of the lens while looking through the viewfinder at a detailed subject...how long does it take for the vibration to dissipate? This exercise will likely surprise you as you can see the vibrations continue. And if your tripod is pretty light, the vibrations may not stop no matter what. If you haven't used large teles before, you may presume an ordinary tripod will be enough--NOPE!

I personally have a heavy shutter finger which causes many "lost" images due to my "slamming" the shutter button down. As a test, try using the 2 second timer which also locks the mirror. This will remove the human factor just for testing.

Are you using a tripod quick release plate? Does it fit the tripod foot/shoe well? If you are simply screwing the tripod screw into the foot, the amount of attachment is likely too small--insufficient coupling. Is your tripod head heavily constucted? That too can be an issue.

Good luck. Shooting super telephoto lenses WELL is a learned skill. Took me almost a year and a new monster tripod to become "passable" at it.
03-22-2009, 10:55 AM   #13
Loyal Site Supporter
Loyal Site Supporter
Canada_Rockies's Avatar

Join Date: Nov 2007
Location: Sparwood, BC, Canada
Photos: Gallery | Albums
Posts: 12,385
Ron, those are excellent points. When I use my 400, and particularly with the 1.4X on the back, it s mounted on the tripod in my avatar. The only change from the rig in my avatar is the camera body is now the K10D instead of the MZ-S. That's a Manfrotto 055B with a Manfrotto 0168 ball head on top. It came with the largish hexagonal quick release plate. I often use the Remote F and 3 sec mirror lock up to ensure sharp photos. Some days it seems that if the guy in the canoe 100 meters away sneezes the whole rig moves. I never extend the centre post of the tripod, even though, as you see, It would be more comfortable up a few inches.

Last edited by Canada_Rockies; 03-22-2009 at 11:04 AM.
03-22-2009, 01:38 PM   #14
Veteran Member
8540tomg's Avatar

Join Date: Feb 2008
Location: Waterloo, Ontario
Photos: Gallery
Posts: 4,461
I haven't notice the KatzEye throwing off the EV. Then again with manual focus lenses I rely less on the meter and work a lot from the Sunny 16 rule.

Lots of good advice above. My own tripod is a little suspect now that I think about it. A solid base is undoubtably the single most important factor in getting better shots. That and a lot of practice. One thing I didn't mention above was the cable switch CS-205 for use with the K10/K20 etc. It is like an electronic cable release and like the remote or self timer will cut down a lot of "heavy finger" vibrations. Good luck with your long lens.

Tom G

Last edited by 8540tomg; 03-22-2009 at 05:24 PM. Reason: typo
03-22-2009, 01:47 PM   #15
Veteran Member




Join Date: Nov 2006
Location: md-usa
Photos: Gallery | Albums
Posts: 2,580
My k100d worked best with the smc 500mm I had because of the exposure errors with k10d/k20d but a real bear to focus with the digital bodies and my old eyes. I had to sell off some stuff to try and get a good long af lens. I got some good shots with the 500mm f4.5 but really had to work for 'em.
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!
500mm, f4.5, focus, focus issues, k-mount, k10, k20, length, pentax lens, slr lens, smc 500mm f4.5

Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Rare SMC Pentax 85mm F2.2 Soft Focus (US/CAN) ga-hing Sold Items 13 10-15-2010 03:33 PM
Soft focus on SMC Pentax-DA 18-55mm F3.5-5.6 AL WR khvatov Pentax SLR Lens Discussion 7 07-29-2010 05:47 AM
For Sale - Sold: SMC PENTAX-FA 1:2.8 28mm -SOFT FOCUS- tsiklop Sold Items 4 01-04-2010 09:52 AM
For Sale - Sold: SMC Pentax FA 85mm F2.8 Soft Focus Lens tsiklop Sold Items 8 12-26-2009 02:14 PM
For Sale - Sold: SMC Pentax-FA 28mm 2.8 SOFT FOCUS Lens tsiklop Sold Items 3 12-22-2009 09:37 AM



All times are GMT -7. The time now is 12:57 PM. | 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