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Forum: Film Processing, Scanning, and Darkroom
12-25-2023, 02:52 AM
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There's a number of similar stories. Collaborations between German manufacturers were common and rarely public knowledge. Collaborations between Japanese companies were similarly frequent and obfuscated. Even now, when many of those makers do not exist, or have live reputations to protect, secrecy seems to be the norm. All cats, please exit bags . . .
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Forum: Film Processing, Scanning, and Darkroom
12-24-2023, 04:19 AM
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Jackpot! Many thanks for the picture post - if I repeat this picture on Delta, is there somewhere I can direct a credit for you?
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Forum: Lens Clubs
07-07-2023, 12:57 AM
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Cineluxes do colour for sure! Lovely tonality in those images. Thanks.
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Forum: Pentax Medium Format
05-11-2023, 05:52 AM
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Good point: adaptors can cause issues: the Pentax 645 > L mount adaptor is different to the OM35 one and could be a factor.
However, mindful of the possibility of accidentally creating a tilt lens, I made multiple tests of opposite sides of the outer zones. I focus bracket based on magnified views of the relevant section of each image, but the SMC-A made it difficult, because in Zone D you simply don't have enough resolution to see where you're focusing. It is a big ask in that setup and few lenses thrive there. I'm adding a comparison of the MTF charts at 16:9.net, which illustrates the problem I'm seeing.
If you're not shifting, I would expect the A and FA to perform equally - and well - but it now seems to me that purpose of the more complex FA design was to improve film-frame corners and wide aperture behaviour, refine the rendering and simplify distortion. I don't think Pentax improved centre-frame resolution stopped down at all, which accounts for the A's popularity when used on sub-MF sensors.
As to our different experiences of the OM35/2.8 Shift . . . it only seems like you and I care! I'm amenable to downgrading my view of the Olympus with the authority of the finicky GFX100S - but would want to re-test them on the even more ruthless M43 sensor - although I couldn't reach Zone D with it. There's definitely mileage in adapting 35mm shift lenses to GFX: in your shoes I would have the Samyang 24PC, but want my old Canon 24 TSE II. Enjoy!
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Forum: Pentax Medium Format
05-10-2023, 12:30 AM
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The truth lies in comparing multiple tests, but as you say, the details matter, and there are a few factors to bear in mind when comparing dissimilar results:
1. Results often look satisfactory until compared with something better. Remember how pleased we were with DVD quality? Compared to 4K, it now looks unbearable. And try watching VHS in 2023. This test caught me out twice: I wasn't impressed by the Olympus 35/2.8 Shift in 2007 because the Zeiss PC-Distagon made it look bad. And I wouldn't touch a Nikon 35 PC-Nikkor because – sat next to either – it seemed like junk. However, I was always pleased with the 645 FA35's sharpness - until now, testing this sample this way, leading to . . .
2. While I'm confident about the performance of these 645 35/3.5 samples, possibly they aren't great copies, and your A is better – but reviewing Pentax' MTF after the test, it predicts what I'm seeing with 4.3 micron pixels. However . . .
3. Your XT2 has a pixel pitch of 3.9 microns, so you'd be seeing defects of the Olympus I couldn't access with the S1R. Whereas those fat 'ol 50R pixels are 5.3 microns, and if you're cropping out most of Zone D, and not shifting, even this SMC-A resolves better in central zones at peak apertures, and focuses more accurately, than the FA. If you can live with that bokeh . . .
4. A while ago, I tried to distinguish between two similar 'full frame' lenses by moving them to Micro 4/3. I thought these were both elite-level optics, but the (3.3 micron) Lumix G9 shredded them, and revealed major differences between apertures. M43 (and APS-C) lenses operate at very high resolution: I don't now use any bare 35mm optics on M43 if pixel-level sharpness is a priority. Larger format lenses rarely hack it on smaller cameras: image circle is a trade-off between quality and quantity. That's partly why Speedboosters are such a good idea.
I'd love to lend you my Olympus 35 Shift to try on the 50R: if it doesn't perform better than your SMC-A, maybe I have a bad copy of both the A and the FA.
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Forum: Pentax Medium Format
05-09-2023, 03:48 AM
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The difference in rendering styles is interesting: despite better coatings, the FA isn't as saturated or punchy as the A, but it has dramatically cleaner bokeh. Whatever the pro-and-con differences at pixel level the FA has a much nicer look than the A, particularly in low light and for night photography.
It's also striking how much LESS sharp is either of these first- and second-generation Pentax 645 35/3.5 lenses than the 1978 Olympus 35mm f2.8 Shift.
If proper sharpness is needed, there's a trade-off with image circle size here: the Olympus 35 Shift covers GFX/645Z fine, and is the best of the three, but there's little room for movements. The SMC-A has a bigger image circle, but resolution falls off a cliff if you shift it (on GFX/645Z). The FA is much more useable as a shift lens for medium format digital, but it's slightly less sharp in central areas from f5.6-f11. If you continue that trend line, you find the D-FA has an even smaller image circle, and is probably even better resolving. Will try to test that next.
Still hoping to stir into the mix the 33-55.
---------- Post added 05-09-23 at 03:52 AM ----------
With regard to field curvature, the FA is less problematic, but more noticeable. I know that sounds stupid, but the A's outer zones are so soft that you can't see where the focal plane lies. It's definitely curved – and, also, ripples. The FA's field curvature is more uniform, and because it has the resolution to make the shape visible, you can plot its shape.
If you continue this trend, you get to the SMC-A 55/2.8, which is so sharp, and has so much field curvature, that every picture shot at wide apertures is 'What the hell?!'.
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Forum: Pentax Medium Format
05-05-2023, 01:34 AM
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Just uploaded the first parts of the new P645 35mm comparison:
More coming this weekend . . .
Part 1
Part 2
Part 5
So far, my conclusions are:
• The FA is sharper than the A wide open across the frame, and into the corners at all apertures.
• However the A is slightly sharper in the frame centre from f5.6-f11.
• Both are distinctly less sharp than the Olympus 35/2.8 Shift until f16, when everything looks equally terrible, but consistently so.
The FA and A have different flare issues:
• the bulbous front element of the FA causes more problems with raking, indirect light in some situations (hence the 'compulsory' hood). It has better coatings, but it has a specific internal reflection problem.
• the A is quite well behaved with regard to flare, but a big hood is essential: otherwise it suffers badly with contra-lighting. Coatings are slightly less effective than the Olympus 35/2.8 Shift or the FA35.
The FA 35/5 renders by far the prettiest sunstars of the group, but the prismatic halos won't be everyone's cup of tea.
My testing is at 4.3 microns – so more demanding that the GFX50; not as fussy as the GFX100. At that level (on a 35mm sensor) there's no truth in the idea that f11 is the sharpest aperture: diffraction is visible at f8.
I've not been able to include the FA33-55 because it was DOA from Yahoo Japan. The seller maybe a crook: no reply for two days . . .
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Forum: Pentax Medium Format
04-28-2023, 04:48 AM
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Comparison is a powerful tool, but it only works properly on a smooth and level playing field. It's relatively straightforward to state 'which is best' with regard to each aspect of performance – that's not a matter of opinion. We don't seem to have good information about that, though. Instead, we have lots of opinion, and not enough even fuzzy data to make informed judgments.
An opinion is when someone makes a decision about what's best for them. Is distortion more important to you than resolution? Is centre-frame sharpness more important to you than corner sharpness? Is wide aperture performance more or less important to you than stopped-down shooting? Do you need tilt and shift movements, and what level of deterioration can you live with in the badlands of the outer image circle? What aberrations are you prepared to turn a blind eye to, or are able/willing to correct in post? Is flare a deal-breaker? Or sunstars? Subjectively, how does it handle? Do you prefer short or long focus throws? How much weight will you tolerate? Etc.
Then there's money. We praise disproportionately based on value: expensive lenses are pre-judged because they set expectations high, and vice versa. Cheap lenses attract flattering reviews because value is factored in, but what's cheap for one is expensive for another: is £500 a lot to spend on a lens, or a little? Value is a matter of opinion, but quality is not – and the two often get muddled.
Discriminating fact and opinion seems hard, but it's less so if we disinguish between saying something is good, and saying that we like it.
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Forum: Pentax Medium Format
04-26-2023, 03:47 AM
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For sure. Lenses are assessed by many metrics with varying degrees of rigour by people with differing intentions and priorities deploying differing methods and equipment at different times using different samples at different distances.
It's been said that an imperfect test renders results meaningless, but that's not entirely true. More specifically here, poor method obscures excellence – it's destructive: it can make a good lens look bad, but it can't improve a bad lens, except by temporary comparison. The existence of many shabby tests is therefore just as good as one perfect one: high performance eventually rises to the top. Currently we don't have enough data points for that to have happened – hence the confused picture. More opinion in this case would be helpful: everyone go compare!
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Forum: Pentax Medium Format
04-17-2023, 02:24 PM
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Curious about lighter options that match the performance of the 55/4 . . .
Weight is the deal-breaker for the 45-85mm for me, too: the tilt/shift adaptors for 35mm cameras don't feel up to the job of wrangling a front-heavy 870g.
I now have on order the 33-55 and FA35, and should have the SMC 35/3.5 and 55/2.8 within a week. I'll report back when I've been able to compare them to my Olympus 35 shift on the Panasonic S1R.
As an aside, I'm also interested in how they compare to the Zenzanon 40PE and 45/4 for RF645. Rob also drew my attention to the Contax 645 35/3.5, which seems to be a refinement of the PC-Distagon 35/2.8. Will the SMC still stand tall in this company? People seem to believe so.
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Forum: Pentax Medium Format
04-17-2023, 03:50 AM
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You're in a great position to comment - thanks for your input. It's the long story I'm interested in – don't cut it short on our account please!
In my experience, every P645 and 67 optic passes the test of being able to make great pictures with. They're safely among the best MF lenses that aren't Hasseblad. But the 33-55, SMC 35, FA35, D-FA35 differ by design, will have different merits, and are directly comparable. Similarly, the 45-55mm lenses.
This isn't necessarily my experience, but collating received opinion and weighting against outlying data points (ie, from an AI perspective), would folks agree this is the generally-held view of these lenses in 2023, now largely based on their performance on 35mm and GFX? We might expect a shift of opinion since their original reputation was made using different cameras.
35mm
SMC-A: better in outer image circle than FA35; worse flare, similar geometric distortion, similar CA
FA35: slightly sharper in centre circle than SMC-A, especially at wider apertures; worse field curvature
D-FA: better coatings than either (reduced flare), but otherwise similar to FA
33-55mm: peak performance at 33-35mm, but greater distortion. Comparable centre-frame resolution to 35mm primes at f11-16 but weaker outer image circle
45-55mm
67 55/4 (v3): best optically centre frame; excellent bokeh
55/4 (earlier versions): uncertain how they compare with 45mm variants
645 55/2.8: not sharper overall than 645 45-85: some say yes; others no: likely better at wide apertures; perhaps not as good framewide at f8-f11. Busy bokeh.
645 45-85: best optically in outer image circle at 45-55mm (deteriorates with increased focal length); good bokeh, slightly worse distortion
645 45/2.8: uncertain how compares with 67 45/4 (worse than SMC 35/3.5)
67 45/4: uncertain how compares with 645 45/2.8, but larger image circle likely produces better 'corners'. Flare-prone.
Please feel free to revise or contradict this summary . . .
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Forum: Pentax Medium Format
04-15-2023, 10:30 AM
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I feel this thread should become the definitive statement on Pentax 645 wide angles, but there's still a great deal of contradictory intel.
About 15 years ago, I wrote a review of 35mm shift lenses for 35mm DSLRs and I promised to compare them with the Pentax 645 FA 35mm that I was impressed with via a Zörk PSA. I haven't got round to it yet, but I'm working on it.
At the time, the A-SMC was generally considered the poor relation of the FA. Contrary to what was stated at the top of this thread, and elsewhere in reviews, it's a revised optical formula: the old lens is 9/8; the FA and D-FA are 10/7.
Some are now saying the SMC is sharper than the FA in the outer image circle; some the opposite. Everyone seems to agree that the D-FA is a step up from both all round, but we're seeing pushback against the current valuation: certainly the SMC is great value – and still a great lens – but I don't feel confident about the reputation of the SMC v FA. And now, the long maligned 33-55mm is getting some love.
How the 67 lenses compare optically also seems uncertain: here on the forum, you can read than the 67 45/4 is both much better and much worse than the 645 45-85mm.
Would anyone in the UK like to collaborate on a little series of tests that compare them on a level playing field to some 35mm shift lenses?
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Forum: Lens Clubs
07-23-2022, 01:14 AM
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Enlarger lens royalty right there - but deceptively soft wide open.
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Forum: General Photography
06-30-2022, 12:19 AM
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It would have been easier - and looked better - to find, kill and stuff the hummingbird and suspend it on fishing wire.
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Forum: General Photography
06-27-2022, 02:02 AM
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We should talk more about where are the holes in ball hats, and flyaway hair and the two girlfriends with it, and medication and body positions mitigating arthritis pain, and not squirting strangers' heads. I have learned much about these things from this thread. For the general good, can I ask the admin to retitle it:
“A Case Study in the Tendency of Discussions About Bokeh to Devolve: AKA Where are the Holes in Ball Hats, Flyaway Hair and the Two Girlfriends with It, Medication and Body Positions Mitigating Arthritis Pain, Correctly Dating Digitalis Literature, and Not Squirting Strangers' Heads"?
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Forum: General Photography
06-26-2022, 02:14 AM
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I do not mind dogs, but I prefer cats.
I have a relative who loves dogs and hates cats.
I have another relative who always owned cats, then decided they wanted a dog and now does not like cats.
I had a cat who liked dogs but not other cats.
I knew a dog that hated cats and would chase them, and I knew a cat that hated dogs and would chase them.
I knew a farmer that liked cats and dogs, but the dog accompanied him sheep herding which the cat was bad at, so the farmer preferred the dog on that basis.
Then again, I knew a cat that travelled on the bus with his owner and helped him to busk.
Just backing up what you were saying about cats and dogs.
---------- Post added 06-26-22 at 02:15 AM ----------
I am not so sure about this.
I have a relative who suffers continual abdominal pain and they are not used to it.
Also, Mike was still troubled by arthritis on page 2.
---------- Post added 06-26-22 at 02:18 AM ----------
I am agreeing with what you are saying about water.
But I knew someone who could not tell the difference between waters and coriander tasted metallic to them.
---------- Post added 06-26-22 at 02:23 AM ----------
I worked with someone once who had this problem. They were old and their hair was very fine, and when you sat behind them you could see the fly-away hairs wavering slightly in convection currents and it was very distracting.
I am agreeing with what you're saying in principle, but I don't know how common a scenario this is. I have only ever known one person like this.
---------- Post added 06-26-22 at 02:34 AM ----------
I would like to try this but I do not have a ball cap.
I have a relative who collects ball caps. He has ball caps from many countries around the world and they are in his wardrobe. Sometimes he wears them, but mostly they are just for collecting.
I emailed him and he said there were not little holes in the top of most of his caps and so I cannot agree with you.
---------- Post added 06-26-22 at 02:39 AM ----------
I do not think it is a fad so I cannot support your statement. But I will not quibble over whether you saw a discussion today and I hope you keep taking blue and orange photos.
I knew a photographer once who took a blue and orange photo and it was nice.
---------- Post added 06-26-22 at 02:44 AM ----------
I cannot condone this dangerously untethered propaganda. William Withering's 'An Account of the Foxglove' was first published in 1785. You propose Vincent Van Gogh's grandfather – Vincent Van Gogh – being born AFTER the publication of Withering's pioneering digitalis tome, but it was published four years PRIOR. I therefore cannot get behind your views on bokeh.
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Forum: General Photography
06-25-2022, 01:00 AM
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My goodness: is this still running? The wonky old-man rant was a fun, tongue-in-cheek thread-seeder, but for heaven's sake let's be real.
Bokeh was 'invented' the moment we focused the first lens: when projecting onto a flat medium, everything is bokeh apart from the focal plane. The goal of a lens is to bring the order of focus to the chaos of blur, so naturally it was what photographers initially 'focused on'. Few optical formulations and diaphragm types were in use, and early lenses had a drawing style dominated by aberrations and poor correction, so defocused areas looked broadly similar – when it was even possible to distinguish them from the (centrally placed) subject in focus.
But from the 1950s, diverse, cheap, well-corrected taking lenses existed; many millions of photographs were taken. It became obvious that they rendered differently. People noticed. People named the new things they noticed. One of them was bokeh.
It's inevitable. It's not new, and it's not going away.
Just out of curiosity - what is being proposed here? That we somehow 'abolish' bokeh – suggestions, please? That we put our heads in the sand and stop noticing the pictures we're taking? That we move to AI-controlled focus-stacking cameraphones rendering everything sharp from 3mm to infinity ? It's just nonsense. Please stop. Rant over.
The question of how defocused a background (or foreground) should be is a fruitful one that could/should be taught. Like any artistic decision, there are principles to be sensitively and creatively deployed, not rigid rules to learn by rote. In my view, there has been an over-correction (especially on YouTube) resulting in backgrounds that are too defocused, but that's simply amateurs thinking "if blur is good for subject isolation; more blur is better". Typical rookie error.
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Forum: General Photography
06-22-2022, 12:16 AM
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Well to correct a logic YOUR entire flow revolves around the points of - and which is central to the whole discussion I'm having at you about diverse points of view and how to look at things and what your brain does to the light it sees coming into it - some lenses are old and they have the bokeh (and the newer ones have some of the bokeh has well) - but so does my phone, a bit - and its bokeh is because of its lenses, too (because it has, like, probably 51 of them lined up inside, which is MORE, (and which I can reach for in the digital era to choose between the character of the bokehs, to get the look I'm looking for.
But all those looks have bokeh, which is Bad and you would have been better off with a pinhole or focus stacking than the Takumar 55/2 which is a FARGER, which just totally and irreversibly proves the point I'm making about everything wrong with the world, and how it can be fixed, if only people listen to what I'm saying to them about it instead of taking more pictures of waifs. We have enough waifs already: stop proliferating bokeh-waifs: they are like the lizards but WORSE.
Rant over.
Incidentally, I'm trying to recreate that look from 1970s BBC TV where the candles have huge green and purple tails on them when the camera moves: I watched so much TV in the 1970s, that's how candles actually look now. What lens does that?
Next thread: Aberrations - how can I create them?; Why isn't my camera invisible?; Who's behind the conspiracy to deny us 400-1200mm f1 zoom lenses? Where can I buy stick-on sunstars and a sturdy enough tripod to shoot low-orbit aerial shots of my continent? And: Light - how it ruins everything, and how we were better off without it before stars formed.
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Forum: General Photography
06-21-2022, 02:31 PM
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I am also anti-intra-muscular medication.
But seriously, why oh why cant they just leave a good thing alone and go back to the time when people was black and white and film was made of crystals and cameras was a box with tiny holes instead of these new fangled lenses with their inevitable in-built focal planes and blurs - I mean, that's were we where going wrong, isn't it? Surely thats obvious. I mean it's so obvious I'm just not going to say any more about that for a while and leave you lot too it.
Rant over.
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Forum: General Photography
06-21-2022, 02:13 PM
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I am anti-Jane-Bown. She is another Olympusoid lizard person trying to force her so-called blurrification onto our minds where it is not wanted by us.
I am also anti-Cocteau, because his swimming videos are TERRIBLE with that little red hat and the funny high voice he sings in with words that aren't even WORDS.
And I am anti-satire: I say what I meant and saw what I said, which means I know what I like when I see it, and if you don't or, aren't, your wrong.
Basically, it all boils down to when it comes to Bokeh, that it all went bad when they stopped using pinholes and - started going good when cheap telephones made EVERYTHING go IN FOCUS ALL THE TIME OR THE PICTURE IS WRONG AND SHOULD OF BEEN DELETED! or thrown away.
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Forum: General Photography
06-21-2022, 08:12 AM
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I too am anti-bokeh.
My telephone camera has a feature that allows me to remove bokeh altogether, which is how my eye sees the thing it is that I am looking at. It's called a telephone camera. All the things are there in the focus plain, which is how is should be. When I look at someone, I look at them, and then I look at the background behind their back, or the ground in front of their back - in English, properly, the frontground - and it's all perfectly sharp and focussed onto my eyes. And that is what it should be like all the time.
So pfff. What is this blur everyone is doing? When I have a blur it is because my glasses or dirty, or the perscription of my glass and mind is wrong. I do NOT want to see this in a photograph. It makes me think my glasses are broken or in need of an upgrade. Incidentally - many photographers clean their lenses as if they are made of myrrh and precious magical substances, and then wipe their spectacles with an oily rag, though which they real eye-lenses can't see the world properly? If they get a scratch on their Leica Whateverlux, they cry unicorn tears, but their REAL ACTUAL glasses are covered in cleaning marks and grease and some old hairs. If you think I'm going to take advice from THEM about how a bokeh should be, then you've gone another thing to think about before that happens, my friend.
Bokeh was only invented in 2001 (coincidence? I think not) to sell overpriced, so-called 'fast lenses'. When lenses had tiny holes in them, back in the old days, we did not have it, and things were better without it, when we only had global war and influenza to worry about instead of this so-called invasion in the Ukraine because of the Coronervirus. If only the bokeh had not been there, perhaps we could all have lived happily. But no - it was probably Olympus inventing a fake Japanese word to spread the virus everywhere and give everyone headaches about their blurriness so we do not notice the lizard people who are turning the balls in the frontground of all the Holly Wood films into freaky OVALS that make you think the faces are squashed - but they are not - and I bet that is just what they want you to think. And that's what I think, which is what you should think unless you are one of them as well.
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Forum: Film Processing, Scanning, and Darkroom
06-16-2022, 01:50 PM
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Whereas this is what it would look like if Nikon had made it in the mid-80s . . .
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Forum: Troubleshooting and Beginner Help
06-07-2022, 07:45 AM
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'Boke' means 'stupid, unaware or careless'.
More commonly referenced by English speakers as 'bokeh', it refers to the clutter in the background of your image you forgot to think about while you were busy concentrating on your subject. Amateur photographers are often victims of excessive bokeh because it takes time to develop full awareness of everything that might be happening in the frame.
Photo-bombers take advantage of 'bokeh' to insert themselves inappropriately into your image - sometimes improving it. Here's Dave Chapelle 'doing a bokeh':
To avoid bokeh in your pictures, cultivate awareness of everything in shot - in Japanese, we call this 'Kaze-wo Atsumete;.
If you shoot at a wide enough aperture you can blur out unwanted background elements. This technique is called 'toneh'. For an explanation of 'toneh', see here:
You Tube
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src="https://www.youtube.com/embed/aQ8VodC19-g?controls=1" allowfullscreen>
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Forum: Lens Clubs
06-04-2022, 01:16 AM
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The Meopars, and Meopta lenses in general, are under-rated. Long story. Even 'Meopta's' pre-1945 lenses branded Optikotechnà Pferov are pretty good, and the Meogons are world-class.
There's a useful section on the provenance of Durst Neonons (AKA late Agfa Magnolar) here: Delta Lenses - Agfa. Circumstantial evidence points to Pentax, but I can't be 100% sure. If anyone comes across a Pentax-branded Neonon, please let me know here or at Delta, or post a picture or a serial number.
Rest assured the interest in enlarger (and repro, industrial and projector) lenses continues unabated. PhotoCornucopia's Big List has been a great resource - we're doing our best to pick up where John left off.
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Forum: Film Processing, Scanning, and Darkroom
04-14-2022, 05:00 AM
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It's a fair working hypothesis. Perhaps this will be that thread that goes inert for a decade, then someone pops up and says: “I just found a Pentax EL-80 - anyone know anything about it?:
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