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I wonder why Ricoh/Pentax didn't bring out official D-FA 28mm, 35mm and 50mm 'plastic fantastic' FF version prime lenses to coincide with the release of the K-1? I can't even see any on the road map and I'm sure they'd be popular, not just with K-1 owners. The 35 & 50 could just replace the DA versions in the catalogue. The current one's certainly aren't far off being D-FAs so would hardly cost any more to produce.
Comment by JAK posted on Fuscia (with 50mm plastic fantastic on K-1) at 04/10/2016 - 23:18
Indeed
I wish I could find a better way of doing 3-D on a 2-D screen. Suppose it might work with a sort of virtual reality Viewmaster style attachment on a mobile phone. Alternatively, take it on Kodachrome slide film .... oh it's gone. Back to the wiggle then!
If you wiggle in time it may shed a few pounds off Or I'm open to suggestions for alternatives.
I wish I could find a better way of doing 3-D on a 2-D screen. Suppose it might work with a sort of virtual reality Viewmaster style attachment on a mobile phone. Alternatively, take it on Kodachrome slide film .... oh it's gone. Back to the wiggle then!
If you wiggle in time it may shed a few pounds off Or I'm open to suggestions for alternatives.
Comment by JAK posted on Pentax Stereo Adapter experiment at 04/10/2016 - 20:22
Some will be aware of the old Pentax Stereo Adapter set that came with a 3-D splitter adapter and a slide viewer. I tried to make use of this on APSC cameras but it wasn't wholly successful as it was designed to be used on a standard 35mm camera with a 50mm lens. Well now we have a comparable DSLR so I thought it would be worth trying again.
While anaglyph 3-D images work, they do require those strange red and blue glasses. Then the old stereo viewer Pentax provided was for viewing 35mm slides, not digital files! However a new variation has been invented, wiggle gifs! While dedicated compact cameras can produce 3-D images I thought I would try it out with the Pentax adapter with the resultant stereo frame converted to a gif in Stereo Photo Maker (stphmkre) which allows saving files in various stereo formats.
PU doesn't allow uploading gifs so the image links to my home server instead so it might not work overnight UK time (so if it isn't there, try it again later!)
My first experimental wiggle gif!
Pentax K-1 with DA50mm f1.8 lens @ f6.3 and Pentax Stereo Adapter.
While anaglyph 3-D images work, they do require those strange red and blue glasses. Then the old stereo viewer Pentax provided was for viewing 35mm slides, not digital files! However a new variation has been invented, wiggle gifs! While dedicated compact cameras can produce 3-D images I thought I would try it out with the Pentax adapter with the resultant stereo frame converted to a gif in Stereo Photo Maker (stphmkre) which allows saving files in various stereo formats.
PU doesn't allow uploading gifs so the image links to my home server instead so it might not work overnight UK time (so if it isn't there, try it again later!)
My first experimental wiggle gif!
Pentax K-1 with DA50mm f1.8 lens @ f6.3 and Pentax Stereo Adapter.
Comment by JAK posted on Pentax Stereo Adapter experiment at 04/10/2016 - 16:30
Thank you John
Comment by JAK posted on Fuscia (with 50mm plastic fantastic on K-1) at 04/10/2016 - 15:48
I've been proving to myself that the APSC 50mm f1.8 plastic fantastic works as well as any other Pentax 50mm lens on the K-1 in full frame mode. (I might be wrong of course!)
The image has had a tiny crop to remove edge distractions but is almost complete. On my monitor it looks quite 3-D.
Fuscia
K-1, DA50mm f1.8 @ f5.6, 1/160", ISO 200, -1.3EV focused as close at it allowed.
The image has had a tiny crop to remove edge distractions but is almost complete. On my monitor it looks quite 3-D.
Fuscia
K-1, DA50mm f1.8 @ f5.6, 1/160", ISO 200, -1.3EV focused as close at it allowed.
Comment by JAK posted on Fuscia (with 50mm plastic fantastic on K-1) at 04/10/2016 - 13:29
Wow, look good to me!
Comment by JAK posted on Aurora over Mosfellsbær at 04/10/2016 - 00:43
Rather than replace it, why can't Sigma clean it? Even regrind it if need be.
Comment by JAK posted on eBay Sigma 18-200mm BIN £70 or offer at 03/10/2016 - 10:32
Probably to buy K-1s!
Comment by JAK posted on Why is there so many K3 for sale at 02/10/2016 - 21:57
Well yes, the first is the zoom Sigma and the second the prime Samyang.
I did tweak the Samyang image in Hemi-fisheye, though it isn't overly fish-eye without doing that. This is the un-tweaked version:
Despite both being 12mm, the Samyang has a much greater field of view and seems sharper, albeit the geometry of the Sigma shows really good rectilinearity.
Some 100% pixel crops from both.
Sigma centre
Sigma edge
De-fished Samyang centre
De-fished Samyang edge
Clearly the Samyang wins on sharpness, though stopping the Sigma down to around f11 did improve it a little, but still not as good as the Samyang.
Both lenses give really great wide images when the whole frame is used, but the Samyang has the wider field of view and its result stand cropping much better. If good geometry is required the Sigma might be the more useful lens depending on circumstances and it can be zoomed in to 24mm.
I believe the Samyang has the widest field of view of any full frame lens, period. The Sigma does compete with marques from other (non Pentax) brands with the same range and there is a newer version of it, but not in a Pentax mount.
Just one final observation, the Samyang is an 'A' type lens that requires manual focussing, but given the depth of field it would be hard not to manage to do that!
I must admit I was very surprised how good the Samyang proves to be and how well Hemi-Fisheye straightens it out.
I did tweak the Samyang image in Hemi-fisheye, though it isn't overly fish-eye without doing that. This is the un-tweaked version:
Despite both being 12mm, the Samyang has a much greater field of view and seems sharper, albeit the geometry of the Sigma shows really good rectilinearity.
Some 100% pixel crops from both.
Sigma centre
Sigma edge
De-fished Samyang centre
De-fished Samyang edge
Clearly the Samyang wins on sharpness, though stopping the Sigma down to around f11 did improve it a little, but still not as good as the Samyang.
Both lenses give really great wide images when the whole frame is used, but the Samyang has the wider field of view and its result stand cropping much better. If good geometry is required the Sigma might be the more useful lens depending on circumstances and it can be zoomed in to 24mm.
I believe the Samyang has the widest field of view of any full frame lens, period. The Sigma does compete with marques from other (non Pentax) brands with the same range and there is a newer version of it, but not in a Pentax mount.
Just one final observation, the Samyang is an 'A' type lens that requires manual focussing, but given the depth of field it would be hard not to manage to do that!
I must admit I was very surprised how good the Samyang proves to be and how well Hemi-Fisheye straightens it out.
Comment by JAK posted on 12mm Lenses on a K-1 at 02/10/2016 - 19:58
On the photo it looks more like an oil smear. I wouldn't have thought the lens was old enough to suffer with fungus issues yet as it's only been available for seven years (released early 2009.) If it is fungus though a strong dose of sunlight UV might kill it off if it isn't well developed. It looks mint externally and the price at £70 or less seems reasonable. (Why did a 'less than' sign here truncate the post initially??)
The trouble is though that one doesn't want to risk fungus spreading to other lenses.
The trouble is though that one doesn't want to risk fungus spreading to other lenses.
Comment by JAK posted on eBay Sigma 18-200mm BIN £70 or offer at 02/10/2016 - 19:14
