DA lenses on K-1 II
The DA* 300mm on its own is FF compatible.
Pentax Lenses 28-80 F, 300 DA*, 80-200 F, 35 F2.4 AL, M50 F1.7, 28-105 DFA, 20 F4 SMC
ONE UNITED Member
I don't understand why you have taken this route?
I've got some old glass that I will use as well, but a lot of gaps in coverage. The Adaptall 2 SP lenses are really good, but a little heavy for walking, where the 55-300mm is ideal, and I've nothing FF wider than 28mm.
... at some time you will need FA lenses to get the full potential.
The DA* 300mm on its own is FF compatible.
The DA* 300mm on its own is FF compatible.
The K3 or KP or the new aps-c model will give you more MP than the K1 in crop mode, but I have cropped the K1 really agressively with excellent results. If you are going to eventually transition to a FF based system with FF lenses your current approach seems the right one.
My Flickr page
The K3 or KP or the new aps-c model will give you more MP than the K1 in crop mode
My Flickr page
Or this:
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My Flickr page
Or this:
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17 posts
13 years
I've created a list showing usable pixel width & height for Sigma EX 10-20mm F/4-5.6, SMC Pentax-DA 16-45mm F/4, SMC Pentax-DA 55-300mm F/4-5.8 and SMC Pentax-DA* 300mm F/4 with HD Pentax-DA 1.4x converter. I also tested the 1.4 converter with the 55-300mm at 300mm.
My method was to take an image (not using hood *) and crop with original aspect ratio, to where the corners are obviously darkening, as that's likely to be acceptable in most cases. From the pixel size of the crop, I calculate the percentage of full frame width & height, and the equivalent focal length of the cropped area. I may not have been entirely consistent with selecting the border, but it's good enough for me. I wasn't judging any other quality here, and I may look in more detail another time.
The image here (300mm+1.4x) for instance would be cropped roughly as shown in magenta, with the black box showing approximate camera crop size:
The list is here as a pdf.
My results suggest all these lenses are able to be used in FF mode, with some level of cropping.
The Sigma really struggled with dark sides, but still works out significantly wider than using cropped mode. Even though 10mm becomes equivalent to 12mm, with camera crop mode it would be 15mm equivalent. There's a little room for using a bit more width by adjusting the aspect ratio.
The Pentax 16-45mm has little benefit using below 20mm, unless using a near panoramic ratio, which would work well for most cases. It is pretty good from 20mm on, and excellent at 28 to 45mm.
The Pentax 55-300mm was a bit of a surprise, very usable at all ranges, even with the 1.4x converter. With the longer range, I'd expect to be cropping, so it's nice to have a bit more room to capture the bird before it flies out of frame.
The 300mm + 1.4x converter was losing a bit more corner than I'd hoped, but it's still able to provide far more than using camera crop mode.
I hope this is of use to those wondering about how useful their DA lens collection might be if they go to full frame. My kit will be fine for me for now.
* I also noticed the Sigma hood is remarkably close to the crop size, a bit over 100 pixel border and near rectangular - this is why I didn't use hoods for the test:
Mike