Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-07-2019, 12:41 PM - 1 Like   #1081
Pentaxian
timw4mail's Avatar

Join Date: Apr 2017
Location: Driving a Mirage
Photos: Gallery | Albums
Posts: 1,670
QuoteOriginally posted by jack002 Quote
Yes, the adaptall 2, as I understand. I now have a 500mm lens that is also f8, so I expect this to work the same, just better focus
Focus on a mirror is always somewhat tricky, though.

10-07-2019, 12:43 PM - 1 Like   #1082
Site Supporter
Site Supporter




Join Date: Oct 2018
Location: Nashville
Photos: Albums
Posts: 394
QuoteOriginally posted by timw4mail Quote
Focus on a mirror is always somewhat tricky, though.
I had a Celestron mirror and the "focus" knob spun quite a number of revolutions, and I went all the way through the focus spread and back, yet still could not get a decent focus on the moon. I'm hoping my old Russian spy era MTO 1000 proves to be easier to use!
10-07-2019, 12:46 PM   #1083
Veteran Member
jack002's Avatar

Join Date: Sep 2014
Location: Missouri
Photos: Albums
Posts: 727
I carefully turn focus until sharpest, but I can only hope or wonder if there is any error in that. I thought about taking a short movie and roll over focus back and forth and see if the sweet spot is not where I'm going

UPDATE

I did a test with live view. I look at focus in the OVF, then check it in live view. Checked back several times. They are the same. I am not seeing an issue using the OVF

Last edited by jack002; 10-10-2019 at 12:54 PM.
10-09-2019, 03:18 PM   #1084
Veteran Member
cooltouch's Avatar

Join Date: Jan 2011
Location: Houston, Texas
Photos: Gallery | Albums
Posts: 982
QuoteOriginally posted by timw4mail Quote
Focus on a mirror is always somewhat tricky, though.
No more so, I've found, than with any other long tele lens. The problem with some mirrors is they have a short focus throw, which makes focus very touchy. Fortunately the Tamron 500mm mirror has almost 360 degrees of focus throw and the Sigma 600mm mirror has almost as much throw as the Tamron. But even with this added range, both the Tamron and the Sigma can still be quite touchy.

When I'm focusing with any of my long focal length lenses, whether mirror or refractor, I always take multiple shots of the subject, refocusing between shots. Theory being that, if I take several shots, chances are one of them will be very close to correct focus. Of course, this technique works best for stationary subjects -- or close to stationary, like the moon. Trying to keep up with birds, on the other hand, is a real adventure.

10-14-2019, 07:58 AM   #1085
Pentaxian
timw4mail's Avatar

Join Date: Apr 2017
Location: Driving a Mirage
Photos: Gallery | Albums
Posts: 1,670
QuoteOriginally posted by cooltouch Quote
No more so, I've found, than with any other long tele lens. The problem with some mirrors is they have a short focus throw, which makes focus very touchy. Fortunately the Tamron 500mm mirror has almost 360 degrees of focus throw and the Sigma 600mm mirror has almost as much throw as the Tamron. But even with this added range, both the Tamron and the Sigma can still be quite touchy.

When I'm focusing with any of my long focal length lenses, whether mirror or refractor, I always take multiple shots of the subject, refocusing between shots. Theory being that, if I take several shots, chances are one of them will be very close to correct focus. Of course, this technique works best for stationary subjects -- or close to stationary, like the moon. Trying to keep up with birds, on the other hand, is a real adventure.
That sounds like good advice.
10-15-2019, 01:14 PM - 5 Likes   #1086
smf
Pentaxian
smf's Avatar

Join Date: Feb 2008
Location: Midland, MI
Photos: Gallery | Albums
Posts: 4,083
This image was captured through the glass of a sliding door with a monpod-mounted K-S2 and Tokina 500mm f/8.
(Cross-posted from Picture of The Week)

10-15-2019, 01:18 PM - 1 Like   #1087
Pentaxian
The Squirrel Mafia's Avatar

Join Date: Jan 2015
Posts: 3,046
^ That's a pretty neat looking shot!

10-15-2019, 01:26 PM   #1088
Veteran Member
jack002's Avatar

Join Date: Sep 2014
Location: Missouri
Photos: Albums
Posts: 727
I am working on getting a Tamron 500mm to replace my Minitel. I hope the change is dramatic. Looks like people are getting good results with the Tamron
10-25-2019, 03:29 PM - 3 Likes   #1089
Veteran Member
jack002's Avatar

Join Date: Sep 2014
Location: Missouri
Photos: Albums
Posts: 727
My new Tamron. Adaptall 2 is coming.....

100 thanks to marcusBMG for all his help with this!
10-25-2019, 08:02 PM - 2 Likes   #1090
Seeker of Knowledge
Loyal Site Supporter
aslyfox's Avatar

Join Date: Aug 2016
Location: Topeka, Kansas
Photos: Gallery | Albums
Posts: 24,563
went out with mine today

here are a couple of a Sumatran Tiger Cub at the Topeka Zoo and Conservation Center

K 3 II + Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB) 82 F
Attached Images
View Picture EXIF
PENTAX K-3 II  Photo 
View Picture EXIF
PENTAX K-3 II  Photo 
11-01-2019, 11:28 AM   #1091
Veteran Member
jack002's Avatar

Join Date: Sep 2014
Location: Missouri
Photos: Albums
Posts: 727
I got my adaptall in then the weather was so gray for days. Last night I took this real fast. I'm hoping to get more detail than this. I might need to fine tune the focus more
11-01-2019, 11:34 AM - 2 Likes   #1092
Veteran Member




Join Date: Jan 2009
Location: walking in the air
Posts: 1,315
Tamron Adaptall 500mm f/8 SP Mirror (55B)
11-01-2019, 11:39 AM - 1 Like   #1093
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 2,858
QuoteOriginally posted by jack002 Quote
I might need to fine tune the focus more
AYe looks OoF. Try focus bracketing.
11-01-2019, 05:21 PM - 1 Like   #1094
Veteran Member
jack002's Avatar

Join Date: Sep 2014
Location: Missouri
Photos: Albums
Posts: 727
QuoteOriginally posted by timw4mail Quote
Focus on a mirror is always somewhat tricky, though.
I worked it out. Live view is how I do it now. This is what I did tonight

500mm f8 1/20th 80iso
11-02-2019, 08:40 AM   #1095
Site Supporter
Site Supporter
arnold's Avatar

Join Date: Aug 2012
Location: Queensland
Photos: Gallery | Albums
Posts: 4,292
[IMG][/IMG]
Pentax K1 with a 500mm Tamron SP Mirror lens
Minimal PP. Used tripod and 2 second timer, shake reduction turned OFF. Direct distance to hill about 8 miles.
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!
adapter, bokeh, eclipse, extension, filter, flickr, flowers, k-30, k10d, lens, lenses, light, mirror, mirror lens, paul, pentax lens, pics, pm, post, screws, shot, shots, sigma, t-mount, thanks, thread, tube, view, weekend
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
The * lens club BrendanPK Pentax SLR Lens Discussion 56 08-13-2017 12:38 PM
Soviet Lens Club - MIR lens stevewig Lens Clubs 4 03-25-2016 02:50 AM
The *any and all* lens club yeatzee Lens Clubs 37 11-08-2012 04:50 PM
The 'Hey this lens has glass elements in it' Lens Club Igilligan Lens Clubs 50 11-14-2010 11:07 PM
The scratched lens club... TKH Pentax SLR Lens Discussion 4 01-29-2010 02:51 PM



All times are GMT -7. The time now is 01:14 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