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Forum: Pentax Medium Format
05-27-2020, 09:59 AM
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I don't have the teleconverter myself, but it focuses by moving the elements inside the converter. It's a pretty neat device, able to give some sort of AF capabilities to all sorts of lenses.
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Forum: Pentax SLR Lens Discussion
12-03-2019, 02:20 PM
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There are already some threads discussing how "bigma's" compare to the DFA 150-450mm:
Pentax 150-450 vs Sigma 150-500 questions - PentaxForums.com
Pentax 150-450 vs Sigma 50-500 OS - PentaxForums.com
DFA 150-450 vs Sigma 150-500 - PentaxForums.com
Since I have the DFA 150-450mm and have just acquired a non-OS example of the Sigma DG 150-500mm APO HSM I have been able to take comparison images at different focal lengths.
150mm, the tower on the Telford railway bridge. I thought both lenses were really good at 150mm, both sharp from wide open. The sigma perhaps showed a little more fringing/purpling on some backlit twigs, and the DFA seemed a bit better at coping with the dynamic range from the shady side to the sunlit side. Both lenses were good across the frame, so I haven't bothered with edge crops.
UPDATE: another point of comparison, the sigma apo 100-300mm f4 at 150mm. Very similar iq.
300mm, one of the turrets on Conwy Castle. Unfortunately I couldn't get the tourist in in both sets, so the DFA shots are just of the same point of the turret. Again I was impressed with both lenses, both lenses looked softer at f11 but that I think was due to some shutter shake creeping in at ~1/200th shutter speeds, or perhaps my not letting the lens settle for long enough after changing the aperture on camera before firing the shutter with the cable release.
 800px
450mm (+ sigma @ 500mm), another turret.
Sigma @ 500mm and DFA @ 450mm.
 dfa 450mm
 sigma 500mm
Distant Focus. The house in the crop on the Great Orme is about 3km away (sorry about the pole, best I could do from the driveway). Atmospherics can be the main limiter of IQ in these cases, but this was a favourable, still, clear frosty morning. Neither lens managed to resolve the car number plates! The sigma pics at 500mm highlight a drop off in iq from 440mm. IQ was again good across the frame with no particularly significant falloff visible with either lens in this case.
Bird Focus. I did look at the possibility of acquiring a taxidermy specimen for authenticity but good ones are a fair wack, so I picked the kingfisher ornament up for 99p and the owl for a bit more. This portmanteau was set up at a distance of just over 5m, this was just right for frame coverage with both lenses (the kingfisher ornament is 16.2cm high). Note that the sigma at 500mm has no advantage over the D FA at 450mm due to focus breathing. If you think you might go with the sigma because you get a bit more at 500mm, well at this range, you don't!
Light was so so, clag over the hills blocking the low sun, but I was ok with that as an opportunity to look for fringing. I had to do a fair bit of spot removal on these pics, and tweaking of exposure + a bit of fill light. Two crops. Not much to choose between them on the crop of the kingfisher head apart from the higher level of fringing of the sigma (curiously the fringing gets worse as the f stop increases. A trick of the light perhaps, although I have another lens that does that - the Canon FD 400mm f4.5). The fine detail of the owl fluff is slightly but distinctly clearer with the D FA (less so actually when comparing the whole pics side by side in fastroom).
 
 
 
Close focus. The DFA focuses to 2m, the Sigma to 2.3m. Focus distance here was approx 2.5m. It was immediately noticeable that the sigma focus breathes much more than the DFA. I aimed to cover the width of the banknote. The sigma was at 440mm, the DFA at 330mm (though I didn't exactly equalise the field of view, the DFA is a bit wider). My first efforts were sub standard - shutter shake influencing results with both lenses. I didn't use any extra lighting, just the sunlight filtering into the conservatory, so shutter speeds were sub 1/100th. Corrected second go using mirror lock-up and higher (400) ASA. These test pics most clearly distinguished between the lenses, the DFA distinctly better.
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Forum: General Photography
11-01-2019, 10:59 PM
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They bring no value at all. Editing, post-processing is a tool, as is the camera or lens.
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Forum: Photographic Technique
10-24-2019, 06:55 PM
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A drone is on my list of 'wants'.
Less regulations sending your camera up a kite though. Might be fun with a sacrificial older model theta.
There's a 40ft tripod that keeps popping up on my local kijiji, it folds to a convenient 6ft length and only weighs 34lbs. Not as high as a drone, but almost as cool? I can't find the model, but if it gives anyone ideas, here's a review of a 28 footer with a dandy motorized head.
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Forum: Photographic Technique
10-24-2019, 03:25 PM
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I was lucky enough to get paid to fly around in a helicopter and take photos (with my Pentax of course) a few years ago, and it was an interesting experience.
At the altitude, distance from land, and airspace we were in, I'm not sure that a drone would have been appropriate.
There are quite a few places I'd like to photograph that I think are probably too remote for a drone.
I've sometimes entertained the thought of learning to fly a microlight, as a high wing variety with low stall speed would make quite a good photography platform.
Unfortunately, that's a pretty expensive hobby that likely makes photography look cheap, and apparently it can get quite addictive.
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Forum: General Photography
10-23-2019, 11:39 AM
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I really don't care whether Faceberk knows about us or not, it's of little interest.
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Forum: General Photography
10-23-2019, 07:18 AM
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A wider community would mean less chances to win a prize...so no :D
Jokes aside, I think pentax users are for the most part aware of the existence of pentaxforums (and other pentax websites)
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Forum: Pentax DSLR Discussion
10-23-2019, 02:37 AM
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It was a common issue with the K-5. It's happened to me - during a commercial live music shoot. Miraculously, I found the button and the little rubber collar in the photographers' pit. A Heath Robinson repair with SuperGlue lasted until I sold the body (with full disclosure of course, years ago).
I have smashed a K-3 and two K-1's since then without issues, so I suspect Pentax managed to sort it out.
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Forum: General Photography
10-15-2019, 05:13 PM
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an exclamation point after 'hand held' or 'no post processing' is bragging
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Forum: Post Your Photos!
10-15-2019, 10:57 AM
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Hidden jem of a spot in bayeux france
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Forum: Pentax Medium Format
10-15-2019, 09:47 AM
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Neat images. Cool that you have the ability to build such an adapter. Have you compared the 6x7 lens mechanically shifted vs centered and using the K-1 composition adjust?
Thanks,
barondla
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Forum: Pentax Medium Format
10-10-2019, 07:56 PM
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great accomplishment, lovely pictures
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Forum: General Talk
10-12-2019, 04:19 PM
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I'm just glad there are threads like this so we can spam away and not feel bad.
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Forum: Post Your Photos!
04-07-2019, 09:50 AM
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Our young cat. Very shy yet
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Forum: Pentax K-1 & K-1 II
10-07-2019, 09:20 AM
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I use the "Smart Function" (p. 19 in the K-1 operating manual) wheels a lot. With short lenses I set the "Function dial" to exposure compensation (+/-, p. 46 in the manual) so I can adjust the exposure compensation with the "Setting dial". With 400mm or longer lenses I set the Function dial to "Crop" and adjust the angle of view (p. 43 in the manual) on-the-fly with the Setting dial (APS-C, Full Frame, or 1:1), i.e., if the subject is distant and smaller than the APS-C frame I choose APS-C mode, but if the subject is close enough to fill the Full Frame I set it to Full Frame.
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Forum: Post Your Photos!
10-04-2019, 06:32 AM
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attempt of portait; i used natural light from a window and darkened the shadows in PP
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Forum: Post Your Photos!
10-03-2019, 07:49 AM
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Telescope Celestron 150/750
EQ Mount Celestron AVX
Camera Pentax K-3ii
Taken from Alfalfares - La Serena - Chile
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Forum: Post Your Photos!
10-02-2019, 09:32 PM
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I also see 2 fish, one on either side, with their eye at the same level as the deer eyes, and facing up, just inside the large brown stripes.
Fascinating image. Quite enjoyable. Well done. Thanks.
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Forum: Post Your Photos!
10-02-2019, 10:51 PM
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Now that’s certainly something different, well done.
After a few wee drams I’d be frightened to look at this, who knows what may leap out at me.
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Forum: Post Your Photos!
10-03-2019, 05:43 AM
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:lol:
---------- Post added 10-03-19 at 05:43 AM ----------
:lol: :lol: :lol:
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Forum: Post Your Photos!
10-02-2019, 06:28 PM
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That gives an interesting effect. Very much like an inkblot test. There is an excellent bat-like image towards the bottom.
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Forum: Post Your Photos!
10-01-2019, 10:31 AM
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Revisited and old raw photo to try editing it again. I wish I saved the before - but I felt really improved.
Anyway - thought I'd share it here!
Thanks for looking!
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Forum: Pentax K-1 & K-1 II
08-23-2017, 02:28 PM
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I did some test shots with reds when I first got the camera, but those were trashed a long time ago. I will setup and shoot some dark red roses soon. The image you post looks a little under exposed which definitely helps keep the red channel from blowing out and bleeding to magenta. The K-1 handles reds better than any other Pentax camera I have had (K-7, K-5, K-3). One of my biggest complaints with my K-3 was that red lipstick would bleed to magenta with just a little over exposure.
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Forum: Post Your Photos!
08-22-2017, 09:51 PM
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I don't know but it sure looks like a smiley face!
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Forum: Monthly Photo Contests
12-29-2016, 12:48 PM
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Focus - official competition 2016 CEV Beach Volleyball Satellite
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