Media Technology

This fourth round of the 24mm legacy prime lens shootout features the cheapest 24mm lens that’s been tested so far; it’s a Vivitar(Tokina, 37xxxxxx serial number) that cost $37. It’s up against the Canon FDn 24/2.8, and a recently acquired Olympus H.Zuiko 24/2.8($117 shipped). If you recall from previous rounds of this shootout, the first Olympus 24/2.8 lens that was tested was soft on one side.

Unfortunately this Olympus H.Zuiko 24/2.8 lens is also slightly soft on one side, but it’s not nearly as bad as the other Oly 24mm lens. That softness shouldn’t affect the vignetting, so all three SLR camera lenses were run through the Imatest.com lens testing software. Check the test results photo for full details, but at f/2.8, here are average numbers for light falloff in the corners:

Vivitar(Tokina) 24/2.8: -4.51 (f-stops)

Canon FDn 24/2.8: -4.99 (f-stops)

Olympus H.Zuiko 24/2.8: -5.48 (f-stops)

Those vignetting test results are valid only for this website, because they use calibrated exposures to standardize the testing. The numbers are useful for comparing light falloff between these lenses, and any other lenses this website tests.

Picture of 24mm camera lenses: Vivitar Tokina Olympus H.Zuiko Canon FDn

24mm SLR prime lens test: Vivitar Tokina Olympus H.Zuiko Canon FDn Vignetting Comparison

Ease of focus at long distances: The “5610” street number on the back of the building was the focus point, but it was in shadow, so one level of magnification and focus peaking both had to be used. If half-points could be awarded, that’s what would be used here, because focusing at long distances is weak on all of them. Vivitar 24/2.8 two points, Canon FDn 24/2.8 one point, Olympus H.Zuiko 24/2.8 one point.

Lens contrast: Another case of needing half-points, and not having them. Olympus 24/2.8 one point, zero points for the other two camera lenses, but with different exposures and such, it’s difficult to tell for sure.

Sides of the images: Olympus 24/2.8 gets disqualified due to very slight softness on the left side, but the right side is as strong as the other two lenses. The Vivitar 24/2.8 looks slightly cleaner at the “5610” mark, but maybe just barely softer than the Canon FDn, at the critical mid-field “5620” street number, on the left side. Two points for each.

Center of the images: Vivitar 24/2.8 two points, one point each for the other two lenses, but there could be mitigating factors. The focal lengths of these lenses are all slightly different, which can be seen in the big comparison image picture. That might have made the “5610” mark slightly taller on the Vivitar, so it’s slightly easier to read.

Summary: Your author is now zero-for-three on wide angle Olympus lenses, but if a good one ever comes across the test bench, it might do well. Readers of this column would be advised to stick with the Canon FDn lenses, because they are cheaper and built better. The Vivitar(Tokina) 24/2.8 cost $37 shipped. It was a complete surprise performance-wise, and also because the aperture leaves were stuck together, due to oil on the blades. Whatever sharpness differences it may have had with the Canon could have been focus-related, and/or focal-length related. The Olympus H.Zuiko 24/2.8 was the widest of the three, which can be a slight handicap on the Sony a7R, when it comes to legacy glass. Both the Vivitar and the Canon FDn lens move forward into the final round.

Here is the test image, it’s 13mb in size, **be sure and view it at 100% size**:

https://www.codectest.com/images/24mmLensComparisonVivitarCanonFDnOlympusHZuiko.jpg

Dan Euritt

24mm camera lens shootout, on the Sony a7R: first round

24mm camera lens shootout, on the Sony a7R: second round

24mm camera lens shootout on the Sony a7R: third round, Konica 24mm

In this second round of legacy 28mm prime lens testing, we continue to evaluate the impact of field curvature, at the optimal aperture for landscape shooting. Since two of the lenses being tested are slow 28mm f/3.5 lenses, we’ll also measure light falloff in the corners, using Imatest. The source files for those measurements were set to equal exposures in Photoshop, which made the numbers relevant across both lenses. Here are the corner measurements:

SMC Pentax-M 28mm f/3.5 at f/3.5: -3.34 (f-stops)

Vivitar(Kiron) 28mm f/2.0 at f/4: -2.69 (f-stops)

At ~f/10, both lenses were nearly equal, at -1.99 (f-stops) and -1.86 (f-stops), respectively. To sum it up, you do pay a corner darkness penalty with slow glass on a full-frame sensor, but it’s largely gone after the lens is stopped down hard.

The other SLR lenses that were also evaluated for flat fields on the Sony a7R were the Olympus G-Zuiko Auto-W 28mm f/3.5, the Minolta MD Celtic 28mm f/2.8, and the Canon FDn 28mm f/2.8 lens.

Ease of focus at long distances: The center focus point was on the “5610” street address, on the back of the building. The worst of the bunch for focusing was probably the Canon FDn 28mm lens; it always seemed like either one side or the other was slightly blurry. The Olympus 28mm lens doesn’t have a half-stop mark between f/8 and f/11, which isn’t really focus-related, but it makes the lens feel cheap. The Pentax 28mm lens probably gets the nod here, 1 point.

Lens contrast: Center contrast appears adequate on all of these lenses; this is a subjective call, and it’s influenced by things like changing light conditions, and unequal exposures.

Sides of the images: The Pentax 28mm lens(2 points) takes a narrow win over the Vivitar 28mm lens(1 point). Look at the “5620” street number, towards the left side of the picture, is it readable? The Olympus 28mm lens has a problem with the left side, which seems to be par for the course for that brand. The Minolta MD Celtic 28mm lens is weak on both sides, with the left side being slightly worse. Don’t look to Minolta for a clean 28/2.8 legacy prime, for full-frame sensor use.

Center of the images: The 36mp Sony a7R seems to favor the centers of every lens that it sees. Would there be more substantial differences between the lens center areas of these photos, if a higher density crop sensor camera was used for this testing? The biggest center failure was with the Oly, but it’s not by much, possibly even in the realm of a slight mis-focus. You have to look hard to see it.

Summary: SMC Pentax-M 28mm f/3.5, all the way. In addition to everything else, it could have the smallest amount of CA. The Vivitar 28mm f/2.0 lens is the winner of the consolation round, at least so far. Both copies of that lens showed very slight out-of-focus areas at wider apertures, at the same spots. We’ll take a look at more apertures than just f/10, with both of those lenses, at a later date. Brands to avoid in the legacy 28mm focal length are the losers here; Canon FDn 28mm f/2.8, Olympus due to unreliability(3 out of 3 build quality failures for this author), and all of the legacy Minolta 28mm prime lenses, except possibly the f/2.5 version, which has a problem with yellow glass. That radioactive yellow tint should be fixable with UV light, similar to what you would do with the old Pentax 50mm Takumars.

What is the next step? Locate and test a Pentax 28mm f/2.8 lens; they are reputed to be slightly better than the slower f/3.5 Pentax lens that was tested here. The unfortunate problem with some of these legacy 28mm lenses is the fact that multiple brands only offered five aperture blades in their camera lenses, which can make for some funky bokeh at certain times. In general, though, 28mm is a big step up over 24mm lenses, on the Sony a7R.

Here is the test image, it’s about 21mb in size, **be sure and view it at 100% size**:

https://www.codectest.com/images/28mmLensComparisonOlympusPentaxMinoltaVivitarCanon.jpg

Dan Euritt

This is what the Sony a7R looks like at 10000 ISO, using only ambient lighting from the floodlights at the drag strip. ISO noise reduction on the RAW files was done with DXO Optics Pro 9, using the PRIME setting. There are some comparison photos of the same cars, shot in perfect light on the same day, at f/8, using HSS fill flash from the Sony HLVF60M. The lens used for all shooting was a Vivitar(Kiron) 28mm f/2.0, shot at f/2.8 for the night pictures. At wide apertures like f/2.8, there is a lot of field curvature in this Vivitar lens. No hood was used, and there were issues with flaring and reflections from floodlights on both sides of the track.

This is a problematic comparison, because it’s roughly 1/1000th vs. 1/2000th shutter speed, 10000 ISO vs. 800 ISO, f/8 vs. f/2.8, etc. At slower shutter speeds, vehicle movement blurs the image significantly. Ultimately, though, the biggest problem was that 10000 ISO really kills the resolution, even after cleaning up the noise with DXO Optics Pro in PRIME mode. The best results came from properly exposing the picture, even when that meant raising the ISO from 8000 ISO to 10000 ISO. Leaving a little bit of clean grain kept the image from looking too overprocessed.

The location was trackside at the drag strip at Barona CA, for the Match Race Madness #5 event. This race pits evenly matched competitors in a heads-up start on the tree, no bracket racing, best two out of three wins the match.

Track info at http://baronadrags.com

To purchase pictures from the event, or to check out more photos of this race, please see http://peteliebigphotography.smugmug.com/

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Dan Euritt

Tropical storm Marie developed into a category 5 hurricane in August of 2014, with winds up to 160mph. As Hurricane Marie, it brought Southern California some pretty big surf, which is unusual for the summer months. The eastern Pacific area off of Baja has already seen four category 4 hurricanes this summer, which is the sort of thing that typically happens only during El Nino years.

These hurricane swells arrive in So Cal at steep SSW angles, bringing with them a very strong longshore current, out of the SSW. This energy is focused on beaches facing southwards, like the Wedge in Orange County. The Wedge is also next to a long jetty, that compresses the swell into a corner of the beach, which sort of magnifies and mutates the energy, into something that is both spectacular and dangerous.

This particular swell peaked early in the morning, and most of the bodysurfing photos were taken as the swell was dropping. The only long lens on hand was an old manual focus Tamron SP 60-300 Adaptall-2 zoom lens. It had noticeable vignetting even at f/8, and the resolution wasn’t a match for the 36mp sensor in the Sony a7R. These pics where mostly shot at f/8, iso800, 1/2000th of a second shutter speed.

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Dan Euritt