John Curl's Blowtorch preamplifier part II

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Eperado,
Now if I can just figure out how to use some of the manual features on my now 10 year old digital Nikon body with my older manual Nikon and Nikor lenses I would be a happy camper. It has just been so long that I have to go back and relearn how to use some of the functions to use the manual lenses, but I think they are a better quality than some of the newer plastic optic lenses.
 
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Pentax K3 - I upgraded from a Pentax K20 about 4 months ago which I had for around 7 years. Both cameras are weather sealed and there are a few videos around of owners rinsing them under the tap after a dusty day out, though I never quite brought myself to do that. Lenses:-

50 mm f1.8 Pentax
55 mm f1.4 Pentax
10-20 mm f3.5 Sigma super wide angle - fabulous for landscapes
17-250mm f3.5 Sigma telephoto - great general purpose lens
A standard 28-55 mm f3.5 Pentax kit lens that received surprisingly good reviews (came with the KD20)
An old manual 35 mm f1.4 from the 80's that still works wonderfully - the Pentax lenses are backwards compatible and their primes are awesome.

I use a Canon Powershot for day to day stuff and the iPhone is ok for 'snappies'

I have a early 90's Canon film camera and a Sigma kit lens which will come out of storage in about 2 months. Should be fun to mess around with that for a bit.
 
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I'm still not 'there' with digital. the exposure latitude of film made it far more forgiving for hamfists like me.

Bill, the truth is we were adapted to the particular film or paper we were using. Once we had to change film type or photographic paper, the nonlinearities at the the two extremes (short exposure, long exposure) of that new film/paper became obvious. Playing with the parameters of film/paper development (temperature, time, developer concentration and aging) as well, worked. This for amateur photography.

In professional fields, where developent has to be strictly controlled through speed index, contrast index and base& fog monitoring, one is left with no manipulation tools.
Film/paper density vs relative exposure ( 'characteristic curve') shows the great exposure latidude nonlinearities

After ~2010, digital sensors have much more linear sensitivity and extended dynamic range than any film emulsion
http://www.tate.org.uk/download/file/fid/20941
Clarkvision: Digital Camera Review and Sensor Performance Summary

George
 
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I do fit my old canon lenses now and again for fun when I miss the light that you get through a 50mm f1.4 when using the kit lens. Sadly the micro 4/3 primes are spendy but apparantly very good. And after all the glass should always cost more than the body if you are a photographer. Bit like hifi cost vs software investment...
 
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Bill, the truth is we were adapted to the particular film or paper we were using. Once we had to change film type or photographic paper, the nonlinearities at the the two extremes (short exposure, long exposure) of that new film/paper became obvious. Playing with the parameters of film/paper development (temperature, time, developer concentration and aging) as well, worked. This for amateur photography.

Possibly, although I cannot get good sunset shots on current digital without the faff of tripod and HDR processing and even my first film camera (voiglander range finder) did well. Shame as I have a great view of the sun going down across the fields. Certainly operator error!
 
There were so many variations you could play with in the darkroom as far as printing it was just fun to do. As far as film type and paper that was also a personal choice that we had to make. I could just not get past the colors on Fuji film having grown up with Kodak, it was a very obvious difference in colors. I'm sure you have plenty of options with digital, I just haven't taken the time to learn them, I hardly ever take out the camera any more.
 
although I cannot get good sunset shots on current digital without the faff of tripod and HDR processing
Point and shoot (No HDR at ll ;-)

Kindhornman, happily, Nikon DSLR fullframe bodies are the only ones keeping compatibility with their old lenses, maintaining focus at full aperture while closing the lens to its preset aperture at the moment you take the shoot.
 

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Well, once again, what about analog audio? I am in the midst of making yet another phono stage, to be released sometime in future. Your attitudes don't affect me much, I still have to make my designs work, and work well. I really hope that digital further matures, with both sound and video, but I don't see or hear perfection yet.
 
This everyone should read, Peter Aczel 89 years
Web 'Zine Page 1

Most interesting part:

The gullibility of audiophiles is what astonishes me the most, even after all these years. How is it possible, how did it ever happen, that they trust fairy-tale purveyors and mystic gurus more than reliable sources of scientific information? It wasn’t always so. Between the birth of “high fidelity,” circa 1947, and the early 1970s, what the engineers said was accepted by that generation of hi-fi enthusiasts as the truth. Then, as the ’70s decade grew older, the self-appointed experts without any scientific credentials started to crawl out of the woodwork. For a while they did not overpower the educated technologists but by the early ’80s they did, with the subjective “golden-ear” audio magazines as their chief line of communication. I remember pleading with some of the most brilliant academic and industrial brains in audio to fight against all the nonsense, to speak up loudly and brutally before the untutored drivel gets out of control, but they just laughed, dismissing the “flat-earthers” and “cultists” with a wave of the hand. Now look at them! Talk to the know-it-all young salesman in the high-end audio salon, read the catalogs of Audio Advisor, Music Direct, or any other high-end merchant, read any of the golden-ear audio magazines, check out the subjective audio websites—and weep. The witch doctors have taken over. Even so, all is not lost. You can still read Floyd Toole and Siegfried Linkwitz on loudspeakers, Douglas Self and Bob Cordell on amplifiers, David Rich (hometheaterhifi.com) on miscellaneous audio subjects, and a few others in that very sparsely populated club. (I am not including The Audio Critic, now that it has become almost silent.) Once you have breathed that atmosphere, you will have a pretty good idea what advice to ignore.
 
Peter Aczel is a complicated guy. I first was in contact with him in the late '70's and he published some TIM measurements that John Meyer and I made with a few audiophile amplifiers. I got into 'hot water' with Audio Research, since their first solid state power amp was one of the slowest in the marketplace. Of course, I can't help those who ignore slew rate, like they did. Interestingly enough both Nelson Pass's Threshold design and Jon Iverson's power amp, the ElectroResearch came through with flying colors. The other amp that failed was the Phase Linear (400 or 700) I can't remember which. In THOSE days Aczel seemed open minded.
However, years later, when he relaunched his mag, he was TOTALLY double blind. Just like many here, and his magazine went out of its way to badmouth just about everybody in the audio business who didn't think like them. They separated the 'white hats' from the 'black hats' and trashed everybody they could. They ignored me, so I promoted myself as a 'grey hat'.
Their reviews were not 'professional' as I know the term. They went out of their way to trash one of my early designs, without even consulting me about it. There WAS a mistake in the manufacture of the design that got by me, (even though I gave written instructions how to avoid it), and it had to be fixed, as it was, but I was 'trashed' for removing Scott's AD712 and replacing it with an open loop follower (more sophisticated and lower distortion than Scott's latest version here recently). They, like so many here, can just not understand why a single op amp could make a difference, but the reviewers did, so it was a worthwhile change. I still use the same design today in my latest products, it works that well.
In any case, public badmouthing of me in print, has annoyed me, especially when it potentially biases future reviews of my designs. For example, Dr. Rich was pretty sure that the A21 power amp would suffer the same way as the HCA2200mk2, in measurement, BUT it did not, BECAUSE I fixed the original oversight (not mine) by changing part values.
All in all, I prefer a level playing field, and Aczel did not offer one in his publication.
 
Ah. Still not enough DR for the effect I want. I reckon you are about 4 stops under what I need.

It's there, he just chose to process it differently than you wished.

With a newer Sony EXMOR sensor (among others), you're already several stops ahead of any film commonly used (and matching/slightly ahead of some of your really nice B&W films). The log nature of film does well to compress highlights (crushing contrast), however, that oftentimes makes for some lovely tonality.

Film and digital both have greater DR than available on the printed medium, so it still remains a question of squeezing the image fit the printed DR.

Film's greatest advantage at this point is that it's pretty inexpensive to get a 4x5 photo, all in a single shot (and not need to fight the insults and vagaries of stitching images).

This all reminds me that I should get out and shoot more often.
 
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There were so many variations you could play with in the darkroom as far as printing it was just fun to do. As far as film type and paper that was also a personal choice that we had to make. I could just not get past the colors on Fuji film having grown up with Kodak, it was a very obvious difference in colors. I'm sure you have plenty of options with digital, I just haven't taken the time to learn them, I hardly ever take out the camera any more.

Yes Steven
The distinction btn 'personal choise' and precision in reproduction is the sole reason I posted on photography on this thread. :)

Hobby &Art
As an amateur photographer, I started with an 6cmx6cm Lubitel 2 camera, russian2
I was developing the chemical emulsions myself following prescriptions written in books, I was contact-printing using the sun light as a light source, later I built a projector, all for b&w.
I was reading books, I was shooting I was paying for my technical mistakes, I was learning (technical) photography and I was enjoying (artistic) photography
Then with an Olympus OM-10 and Zuiko 50mm lens I moved to color 35mm positives (*) and wall projector. I was still learning and enjoying artistic photography.

Profession and precision
I had to do industrial film X/Gamma-Ray used as a materials investigative method (ASNT LII, LIII).
100% objective methods vs 50% subjective methods of my earlier amateur photography years.
In the end I saw the digital X/Gamma-Ray revolution (up to 50um system resolution) unfolding.

Today, I am a casual user of small, auto digital photo cameras. Either my mind's or the humble camera's snapshots is what i care about (age).

George
(*) Fuji color positives were 'showting', (only good for landscapes) compared to KODAC and AGFA.
AGFAs were very delicate, excelent for portraits, KODACs good for anything (ILFORD b&w was an other issue)
 
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Yes Steven
The distinction btn 'personal choise' and precision in reproduction is the sole reason I posted on photography on this thread. :)

Hobby &Art
As an amateur photographer, I started with an 6cmx6cm Lubitel 2 camera, russian2

We had Lubitels at school. Only B&W but with only 12 shots per roll you had to think about what you were doing. Huge fun but I was too young to properly appreciate it.
 
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It's there, he just chose to process it differently than you wished.

Possibly, or I am assuming that if I can see it the camera really ought to be able to capture it. We get the most wonderful pinks in the sky as the sun hits about 5 degrees above the horizon and when the oilseed rape is in flower the yellow of the field, pink of the sky and orange of the sun looks beautiful, but a biatch to capture. If you want a black field or white sky no problem!

Tripod is broken and I don't have a ND filter suitable. One spring will get it.
 
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