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Since the late 1970's, I have had my eye on a reflex lens. The idea of getting all that magnification into such a small package fascinates me. Over the years, we have owned a classic Celetron 8" catadioptric telescope, and currently have a 4" Meade, which is far more portable. I have tested a couple of 500mm camera cat's, but the image quality was way poorer than a crop from my 18-250 zoom would yield.
A few months ago, Tony mentioned that he had a Tokina RMC 500mm cat. These are rated as at the upper end of the scale, so at last this week, finances and timing coincided to let me swing past his shop. The lens was in pristine condition - even the ND filters were still in the original wrapping! The external cardboard box is not even scuffed! Not bad for something that is maybe 30 years old. WayneBenedet pointed out that the Tokina designers are an offshoot from Nikon, so the quality is certainly in by design.
I took a couple of shots inside and outside his shop, and the moment I felt the silky smooth smooth, long throw focus, I was well on my way to sold. The images did the rest:
rdungan1918 asked for pictures, so for character, here is Tony holding it whilst making out the invoice:
For science, here is a comparison of my recent acquisitions:
From left to right, in order of focal length:
Tokina 11-16mm f2.8 'zoom' Alpha mount, Tamron 28mm f2.8 M42, Yashinon 55mm f1.8 M42, Tokina 500mm f8 M42
I love that fact that the two physically biggest lenses are the shortest and longest, by a factor of nearly 50! The 500mm fits into my walkabout camera back more easily than the 11-16, which has a massive tulip lens-hood. It's also interesting to note that the fastest lens (f1.8) has the smallest diameter! All in the geometry.
And the 500mm performance? It's not the easiest lens to use. It requires thought, care and planning. The field of view is very narrow. On my 23mm APS-C sensor, it is the equivalent of a 750mm lens full frame. That's roughly 15x magnification onto the sensor, at around a 4o field of view - it is easy to get lost, and you can't just zoom out, get your bearings, and then zoom back in. It's not a swing-about-wildly-hoping-to-follow-the-action lens either. But if you plan your shot, and are a little patient, it does well.
I took it with me to dog training, and sat about 20-30 metres from the agility setup.
The manual included data on the "MTF" of the lens, showing an 80% centre value for 60 lines per mm. I had to Google MTF, and found this very good article . My 16MP sensor runs at around 186 pixels/ mm, so it's not pixel sharp as the image lands. But it was interesting to note how well its images respond to unsharp masking. I suspect that unsharp masks, which are essentially tunable dynamic contrast enhancers, deal with this sort of softness very well.
I poked around briefly with video (a crop factor of 1.83 --> over 900mma on 35mm film!), but that is definitely tripod territory.
We're off to the Kruger National Park in July, and visit other game reserves moderately regularly, so whilst this is not a walkabout lens, I think it's going to produce some nice images going forward.
Well worth the R1050 (~ US$65).
A few months ago, Tony mentioned that he had a Tokina RMC 500mm cat. These are rated as at the upper end of the scale, so at last this week, finances and timing coincided to let me swing past his shop. The lens was in pristine condition - even the ND filters were still in the original wrapping! The external cardboard box is not even scuffed! Not bad for something that is maybe 30 years old. WayneBenedet pointed out that the Tokina designers are an offshoot from Nikon, so the quality is certainly in by design.
I took a couple of shots inside and outside his shop, and the moment I felt the silky smooth smooth, long throw focus, I was well on my way to sold. The images did the rest:
rdungan1918 asked for pictures, so for character, here is Tony holding it whilst making out the invoice:
For science, here is a comparison of my recent acquisitions:
From left to right, in order of focal length:
Tokina 11-16mm f2.8 'zoom' Alpha mount, Tamron 28mm f2.8 M42, Yashinon 55mm f1.8 M42, Tokina 500mm f8 M42
And the 500mm performance? It's not the easiest lens to use. It requires thought, care and planning. The field of view is very narrow. On my 23mm APS-C sensor, it is the equivalent of a 750mm lens full frame. That's roughly 15x magnification onto the sensor, at around a 4o field of view - it is easy to get lost, and you can't just zoom out, get your bearings, and then zoom back in. It's not a swing-about-wildly-hoping-to-follow-the-action lens either. But if you plan your shot, and are a little patient, it does well.
I took it with me to dog training, and sat about 20-30 metres from the agility setup.
The manual included data on the "MTF" of the lens, showing an 80% centre value for 60 lines per mm. I had to Google MTF, and found this very good article . My 16MP sensor runs at around 186 pixels/ mm, so it's not pixel sharp as the image lands. But it was interesting to note how well its images respond to unsharp masking. I suspect that unsharp masks, which are essentially tunable dynamic contrast enhancers, deal with this sort of softness very well.
I poked around briefly with video (a crop factor of 1.83 --> over 900mma on 35mm film!), but that is definitely tripod territory.
We're off to the Kruger National Park in July, and visit other game reserves moderately regularly, so whilst this is not a walkabout lens, I think it's going to produce some nice images going forward.
Well worth the R1050 (~ US$65).
To think about more Q1 24
There are so many more. But some is better than none. As @pearwood says, go forth, browse their galleries, leave a comment. Interact a little - we all love the feedback and knowledge that a human with a brain and a soul is looking at our work. Whimsical and fairy tale-like. It manages to not be scary, when it could so easily be totally terrifying. @Annabelle-Chabert (And if you haven't seen her mountainscapes, indulge yourself) @la-tete-ailleurs The sense that the highway somehow emanates from the watcher. @elsableda This feels like an indoor shot, in a studio. Then, as you follow the lights, and where the "subject" is, you realise that this is outdoors, a street shot. And then things turn around, and inside out a bit. @69CameraMan69 Timing is everything. @burningmonk
8 hrs of Song Writing, Cycling and Age of Empires
My son is running an online fundraiser for Beautiful Gate, an NGO helping poor families in Phillipi, CapeTown , SouthAfrica, on 4 May 07h00 - 15h00 UTC https://www.beautifulgatesouthafrica.org/ Follow him on https://www.twitch.tv/lozherd, Donate at https://www.givengain.com/project/collaboration-raising-funds-for-beautiful-gate-south-africa-73145 It involves 8 hours of AgeOfEmpires, SongWriting and Cycling, in alternating segments.
Check if your work being used to train AI
I have just come across this site, and it seems useful - https://haveibeentrained.com/ It identifies images or tags that are in the sources for various AI data training sets. Whilst it's not complete, perfect or enforceable, I think this indicates a way forward. Currently, dA images need to be opted out 1 by 1 - I don't know why the whole deviantArt.com/AfricanObserver URL can't be entered. My work is either standard copyright where other's likenesses are involved, or CC-BY-NC - free to use non-commercially, but if you (intend to) make money from my work, please get in contact. So it being in these data sets is ethically and legal questionable. This is what searching for "AfricanObserver" delivers - a selection of images from this site, some CC-BY-NC, some fully copyrighted. (I suspect the name is a play on the excellent https://haveibeenpwned/ site which checks if your details have been leaked to the internet)
... technology distinguishable from magic
"Any technology distinguishable from magic is insufficiently advanced." Gehm's corollary to Clarke's Third Law Like many people, COVID lockdowns taught me how to livestream. I have always loved tech, and the challenge of streaming was fun. In the last 18 months, I have streamed more lessons that I can recall, somewhere around 150 church services and about 10 larger scale events, including live music, with a 4 piece band. The overarching lesson has to be that "content is king" - the tech is totally secondary. This well known, albeit a little sad for a techie like me. If you ever notice the tech, it has failed. The goal of eventing tech is to create a platform for the content, and to be effectively invisible. People noticing eventing tech can be regarded as failure. So one spends a whole lot of time (and money) on making it as transparent as possible - to achieve the magic of transporting people somewhere else, without noticing. Really, a standard PC or phone webcam and microphone
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Comments8
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Excellent buy for your camera. Looks like the results will be worth the effort of processing the images. My Nikon has a APS-C sensor so my 75-300 zoom has a 450mm reach. I priced some Nikon glass that has a longer reached and concluded the cost is way out of proportion to the amount of use I would give it. A mirror lens may be the answer for a longer lens.