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Forum: Lens Clubs
04-05-2024, 02:15 PM
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Forum: Pentax News and Rumors
03-21-2024, 08:46 AM
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On the other hand, my Pentaxes {“ME” which I acquired recently, and “Super Program” from 1983} - especially the “M” prime lenses - feel light.
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Forum: Lens Clubs
03-13-2024, 02:44 PM
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When only one lassie has it...
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Forum: Pentax News and Rumors
03-12-2024, 11:06 AM
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No, they aren't. Pentax is aiming at people who want to take actual photographs, while Mint is aiming at people who want a lovely shiny precious thing displayed on their shelf.
Yes, exactly. Some wrinkled old farts with a gear collector type mentality will buy the Rollei. Some young trendsters who like the lo-fi look that they consider authentic will buy the Pentax.
But how about. . . and I'm asking you to seriously consider this idea for a moment. . . but how about if there were enough buyers in both potential markets, both the older gear collector types and the young trendy types, that EACH of these cameras might sell enough to make them a viable commercial proposition?
Imagine that. Imagine that there might actually be enough people out there in the world, people who don't think the same way you do and don't want the same things that you want, to make BOTH of these cameras successful.:eek:
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Forum: Pentax News and Rumors
03-07-2024, 06:49 AM
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Forum: Pentax News and Rumors
03-04-2024, 08:22 AM
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Not just artistic decisions, chemistry also had to be kept in control and the printers and processors were fairly high maintenance to ensure what was coming off of them was consistent day to day and met the quality standard of the lab.
A good machine operator was part chemist, part mechanic and part technician.
As an aside, this type of printing is now done by a tri colour LED array exposing the print line by line in much the same way an inkjet printer lays down ink. The machines are now, I expect, mostly self calibrating.
When I left the business we also had print kiosks for digital files that were customer driven, had much less control than the printers in the actual lab and printed on dye sublimation material.
I don't know what is actually being used these days. I don't know if any labs still use photographic paper and wet processing or if the industry has gone to some sort of dry technology, either dye sub or really fancy inkjet.
The main reason why I moved on from the business was because the job was being dumbed down to the point the technicians were little more than monkeys with a few mechanical skills.
It got really boring.
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Forum: Pentax News and Rumors
03-04-2024, 12:36 AM
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All the machines I ran did at least basic colour & density corrections. The really old printers such as the 5S and an old Safai lab that I ran for a few months actually used vacuum tubes with some sort of light sensor (they were called photo multipliers) that were covered in coloured gels. Three tubes, one with a yellow filter, one with a magenta filter and one with a cyan filter.
The exposure was initiated and as the photo multipliers became satisfied they would cause the corresponding cut filter to close the exposure for that colour of light. When they were all happy the shutter would close and it was onto the next negative.
The more modern machines scanned the film for colour and density and moved the cut filters in an appropriate amount for the decided exposure time.
Where the operator had to inject his talents was when the negative fell out of the norm and needed some sort of correction.
An example would be a flash picture that had a brightly lit subject and a dark background. The machine would average the negative and the result would be an underexposed print. So the operator would add density to bring the print density to correct. This was called a subject failure.
Another example would be a scene with a strong colour cast. A common example would be a subject photographed in front of a red barn. The printer would try to neutralize the red colour cast and the resulting print would be too cyan. So the operator would minus cyan (in reality minus yellow and magenta from the filter pack since this was negative printing) to correct the colour cast. This was called a colour failure.
As the technology going into the printers became more refined, vacuum tubes were replaced by electronics and then computers started taking over for some of the heavy lifting that the printer operator did, which increased the range of negatives that the machine could cope with without intervention from the operator, but even the most sophisticated machines that I ran often needed intervention to get it right.
One of the most advanced machine that I ran was the Gretag 3141. It would print a roll of 24 exposures in about 8 seconds, individually scanning each negative for density and colour and correcting each print. The output capacity of the machine was astounding at over eleven thousand prints per hour.
To get there films were spliced together head to tail in master rolls of a few hundred, run through a line processor and then run through the printer onto 1150' rolls of paper which were then run through another line processor, quality checked and sent to packaging where the prints, negatives and customer order envelope were reunited.
This was in the mid 1980s, the computer was crude by todays standard. It's boot sequence was a series of dip switches on the case and the program was fed into it via paper tape.
Communication with the machine was done via teletype using 4 letter commands with varying prompts for setting up printing parameters for such things as basic colour and density balance for a particular film, corrections for over and underexposed negatives, parameters for dealing with colour or subject failure negatives and much much more.
After the machine was set up, the operator invoked the film parameter for whatever master roll was going through (all films were sorted by make and model at the sorting stage). A master roll was one film type only.
Even with how crude it seems now, I was able to get the machines calibrated to the point that we had as low as 5% - 10% paper waste, which was considered a very good hit rate for the machine.
Minilabs with a good printer operator could hit lower paper waste percentages, but the throughput was measured in rolls per hour, not hundreds of rolls per hour.
The minilabs were somewhat speed limited by dint of the films being handled individually. Films were not spliced into big rolls in a minilab.
The 3141 could do somewhere in the range of 400-500 rolls per hour, the first minilab that I ran could hit maybe 20 rolls per hour and by the time I left the business the machines that I ran could hit 50-70 rolls per hour with a well coordinated operator running the show.
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Forum: Pentax News and Rumors
03-02-2024, 04:48 AM
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I can't imagine an answer. I guess you'd need a special lens with some sort of a built-in prism arrangement to turn the image 90 degrees so that you could take a horizontal shot on the vertical frame.
For me, it's one of the major disadvantages of my DSLR and film cameras that I can only shoot in horizontal format, even though sometimes I'd rather shoot something like a portrait in a vertical format.
Probably the best solution would be a square format so that horizontal/verical becomes irrelevant.
:lol::lol::lol::lol::lol::lol::lol:
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Forum: Lens Clubs
10-04-2023, 05:22 PM
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Taken with one of my most favorite lenses, the Takumar 200mm F3.5 Preset.
Kind of a different subject matter though. The Crescent Nebula and surrounding dust.
 NGC6888-Widefield-Small by Colo CJ, on Flickr
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Forum: Pentax Q
07-23-2023, 08:32 AM
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Forum: Pentax Q
08-05-2023, 05:21 AM
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Forum: Pentax K-3 III Monochrome
05-07-2023, 11:55 AM
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Very happy with the camera.
Staircase with skylight, K3iim & DA 15 Ltd, developed in C1.
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Forum: Pentax News and Rumors
04-14-2023, 05:56 AM
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There are unseen hands at work :)
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Forum: Lens Clubs
03-10-2023, 07:58 PM
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Forum: Lens Clubs
03-01-2023, 05:11 AM
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Forum: Lens Clubs
03-01-2023, 12:26 AM
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A couple of images with the super takumars I currently have in my custody. This one with the 85/1.9. Pretty much wide open.
[/url][url=https://flic.kr/p/2ojAYfJ]To take to the sky[/url] by [url=https://www.flickr.com/photos/155361133@N02/]Hans Vedder[/url], on Flickr" target="_blank"> To take to the sky by Hans Vedder, on Flickr
And then a couple from the same morning with the super tak 28/3.5
[/url][url=https://flic.kr/p/2ojzAS7]Geese[/url] by [url=https://www.flickr.com/photos/155361133@N02/]Hans Vedder[/url], on Flickr" target="_blank"> Geese by Hans Vedder, on Flickr
[/url][url=https://flic.kr/p/2ojwWDt]Ash[/url] by [url=https://www.flickr.com/photos/155361133@N02/]Hans Vedder[/url], on Flickr" target="_blank"> Ash by Hans Vedder, on Flickr |
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Forum: Flashes, Lighting, and Studio
01-20-2023, 09:49 PM
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I have Adorama's version, the Flashpoint R2 Pro Mark II, and love it. The first version of the R2 Pro is identical to the XPro. A couple years ago I sold all my Pentax 540 and 360 flashes and HSS cables, switching to the Godox/Flashpoint system. The Godox lights are amazing, and I use several TT520ii flashes.
I also have the TT600 comparable flash, the Flashpoint Zoom R2. It's a great flash. I also use the R2 Mini (TT350, I think). I've used both Profoto and Godox strobes, but to stay within the R2 system I went with the Flashpoint XPLOR 400 Pro (Godox AD400 Pro) when I bought the above flashes. I just added the XPLOR 300 Pro to the collection during Adorama's end-of-year sale a few weeks ago.
I also bought the Flashpoint Transceiver (I don't think Godox has one of these) for $25 in case I ever wanted to use this as a receiver for a non-R2 flash, but I find I use this instead on a second body in Tx mode to trigger all the above lights.
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Forum: General Photography
01-13-2023, 08:53 AM
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First: equivalence says nothing about depth of field for the same lens being used on different formats. Equivalence tells you how to pick a different focal length and a different aperture setting in order to get the same field of view and depth of field on a different format. That is, if you like the field of view and depth of field that you see in an image taken with an APS-C camera, then equivalence tells you what lens and aperture would you use on an FF camera to get BOTH the same field of view and depth of field as in the APS-C image -- different formats require different lenses!
But if you insist on comparing only depth of field for the same lens used on two different formats (which will have two different fields of view), then the answer depends on whether you are comparing equal-sized prints, equal-scale prints, or pixel peeping.
The central optical fact is that a 35mm lens at a given f-stop will create the same physical-diameter blur circles on the film or sensor REGARDLESS of the frame size. When the light rays from a point in the scene pass through the lens and converge to a focus somewhere in the middle of the image, they are not affected by where the frame boundaries lie. (Turning on the crop function of a K-1 or cropping in post doesn't magically change the physics of focus.)
However, the viewer's perception of that physical blur circle (does that bit of the image look in-focus or out-of-focus) strongly depends on the viewing conditions:
1) If the viewer compares two prints of identical size (e.g., two 24" x 36" prints with the full-frame print showing a wider-angle view of the scene), then the full frame print will have MORE depth of field because the same-sized blur circles are a smaller fraction of the frame width and height in the print from the full frame camera. (Yes, this is the opposite of the "equivalence effect" but that's because equivalence has nothing to do with the same lens used on two different formats.)
2) If the viewer compares two prints of scaled size (e.g., comparing a 24" x 36" full frame print to a 16" x 24" crop-sensor print), then both images will have identical depth of field.
3) If the viewer compares the image by pixel-peeping and the cameras have the same pixel sizes (e.g., a 36 MPix K-1 and the 16 MPix K-5) then both images will have identical depth of field --the blur circles are the same size in pixels on both cameras. However, if the APS-C camera has smaller pixels (e.g. the 26MPix K-3II versus the K-1) then the APS-C camera will seem to have shallower depth of field because the blur circles will cover a greater number of the smaller pixels on a high-resolution APS-C camera.
But, again, we must remember that putting the same lens on different formats has NOTHING to do with equivalence.
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Forum: Mini-Challenges, Games, and Photo Stories
01-09-2023, 09:56 AM
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Cold, foggy, and frosty here over the weekend.
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Forum: Lens Clubs
12-28-2022, 02:59 AM
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Forum: Mini-Challenges, Games, and Photo Stories
01-05-2023, 01:57 PM
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Took a walk westward along the Rhone today from Geneva...
Sculpture Bras Du Vent
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Forum: Lens Clubs
12-30-2022, 07:59 PM
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