Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Pentax / Samsung dSLR, K Mount Mirrorless

Reply
 
Thread Tools Search this Thread
Old Nov 15, 2006, 9:55 AM   #1
Member
 
Join Date: Sep 2006
Posts: 36
Default

Anyone here use a mirror lens with their K100? I have a 500mm f8 Russian lens, not sure what make though.

I'm wondering how easy or hard they are to focus? As the K100 still provides focus confirmation for manual focus lens do you find them fairly easy to use? I did get quite a few out of focus shots with my old K1000 film SLR, but hopefully that wouldn't be to common with the K100.

How well does the K100 focusing system handle these lenses?
beethovenspiano is offline   Reply With Quote
Sponsored Links
Old Nov 15, 2006, 10:43 AM   #2
Senior Member
 
ennacac's Avatar
 
Join Date: Mar 2005
Posts: 4,198
Default

I have use a couple, a Celestron 1,200mm and a Pentax 500mm and found them to be kind of a pain to use since they are both very sensitive to even the slightest movement. Also they are fairly slow (understatement) and can only be used with the best lighting.

Tom
ennacac is offline   Reply With Quote
Old Nov 15, 2006, 10:49 AM   #3
TDN
Senior Member
 
TDN's Avatar
 
Join Date: Jun 2006
Posts: 1,288
Default

Also know that mirror lenses have a very particular, "donut-like" bokeh, which a lot of people find ugly. (so do i)

Here's what I mean: http://www.adorama.com/catalog.tpl?o...article=103006


TDN is offline   Reply With Quote
Old Nov 15, 2006, 12:59 PM   #4
Senior Member
 
snostorm's Avatar
 
Join Date: Jan 2004
Location: Chicago Suburb, IL, USA
Posts: 2,770
Default

Hi beethovenspiano,

I have a DS, but that shouldn't make any difference to the subject of the post. I recently bought a Tamron SP500 f8 mirror, and find that with the very narrow DOF, it focuses pretty easily with the DS, both eyeballing (focus seems to "snap in" better than other long lenses that I own) and with the focus indicator (seems to be pretty positive acting as opposed to other lenses where the indicator is sometimes hit-and-miss). The difference in VFs should make little difference as the K100D seems to be just a hair smaller, but is a hair brighter than the DS.

Tom's comment concerning sensitivity to movement is valid. I find that the low relative weight of the lens unfortunately contributes to the situation, and makes heavier refractive lenses of the same FL easier to hold steadily. With the SR of the K100D, this should be less of a problem.

TDN's comment is also true, but I think that with digital Post Processing, the bokeh problem is much less critical than it was with film, and is a reasonable tradeoff for the convenience and otherwise high IQ my lens gives me, and it is possible to sometimes find a shooting angle where bokeh is not really an issue.

Since you already own the lens, it's not a matter of whether you should spend the money, but if it will be useable. IMO, it will be (but I don't know about that particular lens, so can't say for sure).

Scott


snostorm is offline   Reply With Quote
Old Nov 15, 2006, 1:01 PM   #5
Senior Member
 
Join Date: Oct 2005
Posts: 284
Default

that was an interesting read. i was surprised at the different lens comparisons at the end of the article, that as the longer focal length lenses moved further away from the subject they became more blurred than the faster, shorter focal length lenses.
milrodpxpx is offline   Reply With Quote
Old Nov 15, 2006, 1:34 PM   #6
Member
 
Join Date: Sep 2006
Posts: 36
Default

Thanks for the replys everyone. Its a M42 screw mount lens, I have the M42 to Pentax adaptor.

Here's a pic of the lens attached to my K1000.




Attached Images
 
beethovenspiano is offline   Reply With Quote
Old Nov 15, 2006, 5:36 PM   #7
Member
 
Join Date: Sep 2006
Posts: 36
Default

Hmmm looking at the flash protrusion on the K100, i'm wondering if the mirror lens will fit on the camera now. Are all of these mirror lenses about the same size?
beethovenspiano is offline   Reply With Quote
Old Nov 16, 2006, 4:04 AM   #8
Senior Member
 
snostorm's Avatar
 
Join Date: Jan 2004
Location: Chicago Suburb, IL, USA
Posts: 2,770
Default

Hi beethovenspiano,

My Tamron takes an 82mm fiter in front, and is the same diameter the length of the lens (other than the mount). It fits fine on the DS.

Scott
snostorm is offline   Reply With Quote
Old Nov 16, 2006, 5:38 PM   #9
Member
 
Join Date: Sep 2006
Posts: 36
Default

Anyone have any mirror lens samples with their K100?
beethovenspiano is offline   Reply With Quote
Old Nov 16, 2006, 8:05 PM   #10
Senior Member
 
snostorm's Avatar
 
Join Date: Jan 2004
Location: Chicago Suburb, IL, USA
Posts: 2,770
Default

Hi beethovenspiano,

I posted a few shots when I first got the SP500/8. They, and my minireview are located at:

http://www.stevesforums.com/forums/v...mp;forum_id=80

Although I use a DS, the sensor is the same as the K100D, so they should be pretty indicative of what at least the Tamron can do.

Scott


snostorm is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 12:40 PM.