Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
11-17-2007, 09:49 AM   #1
Forum Member




Join Date: Oct 2007
Location: Memphis, TN
Posts: 82
Checklist for using an "A" lens on a K100d

I have a new K100D. I'm enjoying using it with the kit lens and a 800-200 I bought at the same time. Additionally, I've bought two SMC-A Pentax lenses with it, but haven't had the opportunity to try them out yet.

I know to use the non DA lenses I leave them set to Auto, and set my K100d to focus manually. But I think there are other settings? Telling the camera of the lens focal length? Or at least things to consider when using a non DA but SMC-A <type> lenses? I don't plan to use Manual lenses or screw mounts yet but just the SMC-A lenses for this checklist.

I know this information is in the manual somewhere, but I'm hoping to generate a "checklist" of steps to follow so I can get a routine going.

Thanks!

11-17-2007, 11:03 AM   #2
Inactive Account




Join Date: Nov 2007
Location: England
Posts: 39
With camera switched off, attach lens,..switch on and camera will show focal length input of the rear screen,...press navigation control untill your focal length is shown and press 'OK' it does not matter about the setting of 'AF/MF'....at least on my camera. Then focus lens with focus ring, or better still adjust to hyperfocal distance. 'A' lenses are best used in aperture priority mode (Av) to get the best from them.
11-18-2007, 03:42 PM   #3
Forum Member




Join Date: Oct 2007
Location: Memphis, TN
Posts: 82
Original Poster
QuoteOriginally posted by Cornet1 Quote
With camera switched off, attach lens,..switch on and camera will show focal length input of the rear screen,...press navigation control untill your focal length is shown and press 'OK' it does not matter about the setting of 'AF/MF'....at least on my camera. Then focus lens with focus ring, or better still adjust to hyperfocal distance. 'A' lenses are best used in aperture priority mode (Av) to get the best from them.

Thank you very much for that. I did notice that after switching to an "A" lens and turning on the camera is asks right then for the focal length without my going to the menu. I also noted that it asks that when I forgot and left the AF/MF set to MF!

Two questions:
1. What is the "hyperfocal distance"?
2. The focal length I enter is that stamped on the lens body, NOT include the "digital conversion factor" of about 1.5, right?

The reason I ask 2 is that with my Pentax SMC-A 28mm lens the focal length "slider" is pointing pretty close to 35mm, so I slide it to the left a little until it looks closer to 28.

Thanks
11-18-2007, 06:50 PM   #4
Site Supporter
LeoTaylor's Avatar

Join Date: Feb 2007
Location: Connecticut
Photos: Gallery
Posts: 679
I have the "S" option setting selected (Screw) since that allows me to use a Vivitar 2x adaptor that does not pass any electrical signals from lens to camera. Thus, my camera prompts for FL on power up unless there is a modern lens attached. It even prompts if I have NO lens attached. No problem for me, I set the display to the nearest FL step to the lens or zoom I'm going to use. It wants the "real" FL. One nice thing if I'm using the lens for awhile is it remembers the last setting, second and later power ups I just hit OK.

11-19-2007, 04:30 AM   #5
Site Supporter




Join Date: Sep 2006
Location: WV
Posts: 1,493
The camera will, on power up, prompt for FL if, and only if, the shake reduction switch is set to 'On'. If the switch is set to off at power up, you will have to go into the menu to set the FL, since the camera doesn't care what the FL is if SR is off.

Cornet1, why do you say 'A' lenses are best used in aperture priority mode (Av) to get the best from them? That makes no sense to me. Lens properties don't change based on camera modes. I shoot exclusively in manual mode regardless of what lens is on my camera. That way, on a given shot, I determine whether to give priority to aperture or to shutter speed.

But, that's just me.
11-19-2007, 05:28 AM   #6
Inactive Account




Join Date: Nov 2007
Location: England
Posts: 39
Hyperfocal distance, as a practical description, is the setting of the focus ring to give the greatest amount of sharp focus (depth of field) for a given lens aperture...... Look down at the camera with 'A' lens attached,...see the depth of field scale between the aperture ring and the focus ring......notice that it has the same numbers corresponding to the apertures both on the left and right sides. This is to know the area of sharpness around the focus point,...you read from say, f8 on either side and note the distances on the focus ring. By setting the 'infinity' mark to the right 'f8' you are able to get the optimum depth of field for f8...play with your lens and you will see what I mean.

You are correct that you set the actual focal length on the rear screen,....it is to optimise the anti-shake and has nothing to do with the 1.5 coversion factor.

I forgot to mention that it's probably best to set the lens aperture ring to 'A' so that the camera can access the lens iris automatically (you can adjust with the thumb wheel on the back of the camera in 'Av' and manual modes etc)

'MPrince' ....essentially I agree with your post. It would perhaps have been better to say that use of aperture priority gets the best out of the photographer! One of the best things about the 'A' lenses is that they allow the user to retrain his/her mind to think in terms of zone of focus, and optimum aperture etc, rather than just focus point.
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!
camera, checklist, da, dslr, k100d, lens, lenses, photography, smc-a
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Do custom "artistic" or even "funny" lens caps evenexist? lovemehate Pentax SLR Lens Discussion 35 02-10-2016 09:10 AM
K-mount Experts: How to convert a "KAF2" lens to "KF"? panoguy Pentax SLR Lens Discussion 24 07-08-2010 05:20 PM
Is there a cheap "landscape" lens that is better than the 18-55 kit I got with K100D? shaolin95 Pentax SLR Lens Discussion 17 06-13-2009 06:37 AM
"Hunger for a DA*50-135?" or "The DA*50-135 as a bird lens!" or "Iron age birds?" Douglas_of_Sweden Post Your Photos! 4 08-13-2008 06:09 AM
Need "how to" help - K100d with SMC A lens Papersniper Pentax DSLR Discussion 15 11-01-2007 02:05 PM



All times are GMT -7. The time now is 12:49 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