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07-13-2016, 11:56 PM - 1 Like   #76
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QuoteOriginally posted by CypherOz Quote
Pentax needs a big price drop on glass.
in Australia, we need another China/India driven mining boom along with some other "loss of confidence in USA thing"..... then the lenses might be more reasonably priced for us.

08-03-2016, 05:28 PM   #77
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Interesting

QuoteOriginally posted by npc Quote
Unless Ricoh officially confirms this no DA lens should be considered FF compatible.
Just consider the fact that for all the DA lenses sold trough the years nobody did any QC on FF so as long as they were OK on APS-C they would pass, even if decentering or other defects would make them unacceptable on FF. Same is valid for the teleconverter as well.

I've sold my DA 35 2.4 long before I got my a7r so that's the only one I did not test myself on FF. The other DA primes listed here (my own copies) covered FF without much vingetting but there is noticable drop in sharpness outside the APS-C zone (minimal on DA 70 ltd) , especially the extreme corners which are noticably worse than the same focal length old FA/A/etc lenses. Same for DA 40 ltd that I don't see listed above (it convers FF completely) - sharper in the APS-C zone, but much worse in the corners than the old M 40.

I'm not saying that they are unusable on FF but if they were sold to me as "FF lens" then definately I'd want my money back...

For the DA* 60-250 as I've mentioned elsewhere in the forum - I got rid of the dark corners on FF completely by removing the rear baffle - then sharpness is OK across the frame and does not have that sharpness falloff in the corners like my DA primes.

Well I just dropped a grand to buy the DA*200. All I can say is when I got my 16x20 enlargements back, Heavens to Mergatroid!!! Purple Fringing. That's a thousand dollar disappointment!!!
08-03-2016, 10:22 PM   #78
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QuoteOriginally posted by JimBrennan Quote
Well I just dropped a grand to buy the DA*200. All I can say is when I got my 16x20 enlargements back, Heavens to Mergatroid!!! Purple Fringing. That's a thousand dollar disappointment!!!
You could have read reviews (there the same ussues on APSC) and yoyu could also enable the corrections so that it is simply removed..
12-08-2017, 07:52 AM - 1 Like   #79
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Original Poster
Graphs in first post have been updated.

07-26-2018, 11:49 PM   #80
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Always nice to find a updated version of FF K-mount lens line-up.
Thank you so much!
10-15-2019, 06:30 PM   #81
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You know just an observation, but to me the amount of APS-C lenses that are projecting a FF image circle is actually kinda disconcerting in a way. It tells me they could have optimized the size better and perhaps even reduced cost with less glass.
If I have an APS-C system I want the smallest lenses I can have for that sensor, instead of lugging around FF compatible stuff. IMO
10-16-2019, 05:07 AM - 1 Like   #82
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QuoteOriginally posted by Leumas Quote
You know just an observation, but to me the amount of APS-C lenses that are projecting a FF image circle is actually kinda disconcerting in a way. It tells me they could have optimized the size better and perhaps even reduced cost with less glass.
If I have an APS-C system I want the smallest lenses I can have for that sensor, instead of lugging around FF compatible stuff. IMO
This thread is many years old, but here goes...

Optical designers have reasons for the choices they make. In the present case, creating lenses larger than the strict image circle they are tryinhg to illuinate has a few advantages:

1-lets the SR system move things around while still creating an image

2-diminish the effects of aberrations (mostly spherical but others will be impacted too)

3-reduce vignetting

Trust me, no optical designer will include useless glass in their design. It's expensive to purchase, process and assemble.
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