DA 55-300 vs DA* 300 f4

Started Sep 16, 2013 | Discussions thread
jamesm007 Veteran Member • Posts: 5,654
Re: DA 55-300 vs DA* 300 f4

I agree on the Sigma 100-300mm f/4. Don't know why they dropped it

on my Canon is the 60-250/4

You shoot a Pentax DA*60-250mm f/4 on your Canon?

And to all - and is good for the OP to read

I bought the DA55-300mm when it first came out. I am the second or third person here that bought it some ~ five years ago. I have also used it with the K10D and K20D for years with no corrections of CA/PF needed. And am probably its biggest fanboy here

I have a day off. Do you know this is the first time since I bought the K5 9 months ago that I realize its producing much more PF/CA versus the K20D. The K20D only has 5% less resolution than the K5. Its sensor was good. I still own it. Today in Detroit its cloudy so I will have to wait to do back to back comparisons on the K5 versus K20D in PF/CA. I did notice more CA with my Sigma 10-20mm lens in the corners at 10mm when using it at the Woodward Dream Cruise. But I don't shoot and hardly ever read anymore since some time ago. You can tell by my decrease in activity here. Also the reason I lack shots in my library from the K5. I did buy a K5, DA35mm f/2.4 at the start of this year and another lens in hopes of sparking my interest up again. But it faded quickly for some reason. Still a above average camera freak however But I for sure don't know why you would use a Pentax lens on a Canon and how?

And why would both the DA55-300mm and DA*300mm score higher at DXO on a K50 versus the K5? To this day I believe the orig K5 AA filter cover had a flaw that allowed a lot of light in to score high in tests such as DXO but also produced CA. How can an AA filter produce CA/PF. Well it could also be the half bubble lens they put over each pixel to direct more light into the cell (pixel cell; its a pit, a well). This lens could be gathering more light (giving high DXO scores) but since it is a lens it can produce aberrations. That is a law of physics and can't be dismissed as a theory.

Let me show you the dramatic difference I am seeing now. Remember the K20D is still used and highly liked by many as myself; but I use my K5 mainly. The K20D has 14.6mp, its no pushover. The pic of the pigeons show a remarkably accurate range of color and nice detail. This is an out of camera jpg with no PP of CA, only color and sharpness. So if I developed it in raw it would be tack sharp as the K20D and K10D were a little soft with PP sharpness. But there are no strong aberrations through out the pic; the K20D never showed aberrations and I hardly corrected it and did not even think to look for it now! Now I see it! The DA55-300mm on a K20D only showed green type CA sometimes in small pixel peeping levels. This I have written about in the past. How well controlled CA/PF is in the DA55-300mm. Remember other lens and reviewers have seen much more CA/PF with the K5 as well! Its not a DA55-300mm thing.

The corrected pic from above taken with a K5. At least you can correct aberrations these days easy in lightroom and photoshop. But it still hurts micro-contrast!. As Lightroom now has lens profiles I had to buy Lightroom 5 last week to help boost my interest in pics again.

Taken at 300mm f/5.8 days before me getting the K5. Its also strongly back-lit but the K20D avoids blowing highlights at all cost. But being so strongly back lit it should show some aberrations. The K20D or K10D (really GX10) never showed CA/PF with the DA55-300mm, it was not there even at extreme 400% pixel peeping levels; in an amount big enough that needs corrections in PP. At Pixel peeping levels you could see some slight CA but nothing, again to worry about as the pic below helps show. This is why I am convinced now that the orig K5 is doing something with light wrongly! I will do back to back tests with the K20D and K5 and post my results (and with different lens).

 jamesm007's gear list:jamesm007's gear list
Pentax K20D Pentax K-5 Sigma 10-20mm F4-5.6 EX DC HSM Pentax smc DA 55-300mm F4.0-5.8 ED Sigma 17-70mm F2.8-4 DC Macro OS HSM +13 more
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow