Search results for 'back focus' - page 707
Sigma 70-200mm f2.8 EX vs Pentax FA 80-200mm f2.8
Can anybody advise differences and /or advantages regarding these two? I have owned the Sigma for about 6months but haven’t shot a huge amount with it. I also bought the Sigma EX 1.4x & 2x tele converters around the same time. The 70-200 seems sharp and contrasty and I like what I can prod...
Posted by DaveR on 18/04/2008 - 14:10
Sigma 70-200mm f2.8 EX vs Pentax FA 80-200mm f2.8
Which Sigma do you have? Is it a DG one? I have the 70-200 2.8 EX non-DG and I love it, the fast 2.8 is a bonus.. I do not have a teleconverter, but the EX converters I believe are only compatible with the Sigma EX lenses, bnut that could be Sigma B/S :roll: For extra reach I have the EX ...
Posted by Pwynnej on 18/04/2008 - 14:46
Sigma 70-200mm f2.8 EX vs Pentax FA 80-200mm f2.8
Thanks for your thoughts Pwynnej, My lens does not have the DG or Macro designations. I learnt on another forum that Sigma & Tamron have new versions nearly ready to send, for around US$700 & $800 - Adorama is taking advance orders. This will surely drive down the price of our version...
Posted by DaveR on 19/04/2008 - 23:56
Sigma 70-200mm f2.8 EX vs Pentax FA 80-200mm f2.8
Is the lens actually sharp wide open? Just wondering if it has a de-centering defect that may make it a little soft until stopped down, and the camera might then struggle to obtain best focus with it? :?: Dan
Posted by Daniel Bridge on 20/04/2008 - 12:01
24-70 F/4.
that lens has been discussed in detial..do a search... I own one...love it. It can hold it's own with much more expensive glass. constant ap f4, close focus, minimal distortion. some users complained of problems with the rear element (perhaps a faulty batch out there, but something to look for...
Posted by Don on 19/04/2008 - 15:08
DA*16-50mm question
Hi guys... sorry, I haven't been on here for ages.... I just bought a DA*16-50mm lens and I don't feel entirely confident about it but I can't put my finger on whats wrong! Its something to do with the auto focus I don't feel happy about and I know there have been some doubts raised about this len...
Posted by Lee Ash on 19/04/2008 - 14:28
DA*16-50mm question
Is it the focus? It doesn't seem sharp enough some how, buts its very slight. How are you reaching this conclusion i.e that is does not seem quite sharp enough, but it is very slight :?: Are you talking about the lens not being quite sharp enough or do you think that you have an autofocus probl...
Posted by Hyram on 19/04/2008 - 15:05
DA*16-50mm question
I am sure that there is some misinformation about this lens on the internet. I'm sure this is true. Far be it from me to fan such flames, but I have to confess to being quite concerned by the amount of anecdotal (and yes, hence unreliable) evidence suggesting at the very least that the QC on ...
Posted by ChrisA on 19/04/2008 - 17:54
DA*16-50mm question
Hi guys... sorry, I haven't been on here for ages.... I just bought a DA*16-50mm lens and I don't feel entirely confident about it but I can't put my finger on whats wrong! Its something to do with the auto focus I don't feel happy about and I know there have been some doubts raised about this len...
Posted by Pwynnej on 20/04/2008 - 13:25
Tamron lenses with digital bodies
They work exactly the same way on digital SLR's as they would have done on your film camera. If the adaptall mount is the basic K then you have to stop the lenses down manually in M mode. If its the KA adapter then you can also use the lens in the other modes, but always with manual focus.
Posted by philmerrin on 25/04/2008 - 05:29
Which Would you keep FA50 F1.4 or F1.7
This may sound like a silly but I picked up a mint FA50mm F1.7 at the weekend (it looks new) even though I have the F1.4 version. Now I should only keep one ( I suppose ) but which ? I've had the 1.4 for years and I like it a lot but some people say that the 1.7 is sharper. As I never use the ...
Posted by JohnMcD on 25/04/2008 - 22:35
Which Would you keep FA50 F1.4 or F1.7
I did a quick test when I first got my FA50mm 1.4, concentrating on the bokeh more than the sharp areas. Results posted on this thread: https://www.pentaxuser.com/forum/viewtopic.php?t=6214 The 1.4 definitely has smoother rendition of out of focus areas, so for me that makes it preferable to ...
Posted by Daniel Bridge on 25/04/2008 - 23:35
Which Would you keep FA50 F1.4 or F1.7
much as it's a little self defeating for me to say this (I would love an AF 50mm), I'd keep them both unless you really need the money. AF 50mm lenses in good condition only seem to go up in value, and I have never yet sold a good lens and not regretted it later. I do usually regret selling my le...
Posted by JohnMcD on 28/04/2008 - 23:04
SIGMA 10/20 ON PENTAX
I'm never quite sure what people mean by untouched. If it's JPEG in camera it's hard sharpening. If it's RAW in camera then something has made it a JPEG so it would be helpful to know if it's Silky with it's immediate sharpening or Photoshop which probably doesn't sharpen. I'm not sure it m...
Posted by mikew on 28/04/2008 - 17:04
SIGMA 10/20 ON PENTAX
I'm never quite sure what people mean by untouched. If it's JPEG in camera it's hard sharpening. If it's RAW in camera then something has made it a JPEG so it would be helpful to know if it's Silky with it's immediate sharpening or Photoshop which probably doesn't sharpen. I'm not sure it m...
Posted by philstaff on 28/04/2008 - 18:04
SIGMA 10/20 ON PENTAX
I felt exactly the same way when I got mine. I was concerned that it wasn't as sharp I was expecting. I think it was down to two issues: Firstly I think it needs to be given some help focussing. I think you need to ensure it does have some contrasty objects in the focus zone. I now use spot focus...
Posted by mikew on 28/04/2008 - 22:03
SIGMA 10/20 ON PENTAX
Just to clarify: Depth of Field is the area with an acceptable degree of sharpness in an image. Depth of focus is the amount of leeway we have in the positioning of the film plane or sensor position.
Posted by johnriley on 28/04/2008 - 22:32
SIGMA 10/20 ON PENTAX
I always use mine with manual focus on my K110D super as the auto focus seems to be confused. For most shots setting the focus just before infinity gives great results, unless you are shooting something really close. I try to use F8 to F11.
Posted by MX veteran on 29/04/2008 - 01:27
SIGMA 10/20 ON PENTAX
That's not been my experience and I never use manual focus. I just make sure the red spot area is on something with a hard edge and by and large I'm OK on focus now to the extent I don't worry at all. And I guess I was expecting a more forgiving depth of field! Mike
Posted by mikew on 29/04/2008 - 06:54
SIGMA 10/20 ON PENTAX
Neil, some terrific aircraft shots on your website. Would you say a few words about how you go about airshow photography? Thanks Chris and thanks to iceblinker, Martin & Phil for your comments. I appreciate this is going to take this thread off topic so the Mods may want to move it, but in...
Posted by javam on 30/04/2008 - 09:23
