More Wide Angle Converter Questions

[Jan Roovers]

I have updated my pics without rain:
pics without rain

Do you think this is the razorsharp as the Rainox-site promises?
To be honest I hoped for better, but may be I am demanding to much.

[Chris Long]

Yes, it is a bit blurrier than I had hoped for. The image quality seems to fall off fairly quickly from the center out toward the edges. How does the image look in a close-up shot? Also, I'm thinking it won't be as noticeable in motion...

For others who have them (echoing David's question): Is this a common thing with adapters in this price range (the Kenko, Tiffen, etc)? Do they all exhibit a similar level of off-center blur?

[Tom Hardwick]

The answer is a qualified 'yes', in the fact that all wide-angle converters degrade the image quality to a greater or lesser degree. The very best ones are so good that DV's resolving power doesn't show it up, and the less good ones make the losses obvious. They all add a bit of flare and they all soak a bit of light. Nearly all of them add to the distortion.

Converters are often focal length and aperture dependant too - which means they might be pretty sharp when zoomed in a bit and when used at f8. Moving away from these settings will introduce more losses.

I haven't tested the Raynox 0.5x, but the 0.66x I owned was very good indeed at max wide, and pretty bloomin soft at full tele.

tom.

[Jan Roovers]

Yes Chris, I agree.

I hoped for a lens that i could leave on in most cases.

How are the Ceintury lenses? Are they any better.

Tom ,
what you see on my pics, is that normal for you?



How are the Ceintury lenses? Are they any better.

Anybody has one?

[Shawn Mielke]

Yes, Tom, I too am most curious about the Century adaptors.....

[Tom Hardwick]

iIn my wide-angle group test for a British magazine my conclusions were this:

And the winner is…

The Century 0.65x. At just under £400 it’s the most expensive lens on test but it comes with proper lens caps that stay put, it has the best multi-coating and is the sharpest on test, regardless of the aperture used. Wide open it’s at its best in the centre but at smaller apertures the edges catch up. It doesn’t vignette the image at wide angle. There’s no filter thread but the breech lock bayonet is beautifully engineered, smooth as silk and makes the fitting and removal of the lens a quick and secure operation. Note that this only applies to the Sony VX2000, the Canon XM2 and the XL1s, the TRV900 and the DVCAM versions. There is a screw thread version available and a choice of three lens hoods.

It’s the heaviest lens on test at 325g, there’s just noticeable pincushion distortion at telephoto but overall it’s the winner. My only gripe is this. For a lens that isn’t very powerful it distorts straight lines too much. If I fit the 0.5x Cavision and zoom up to match the Century’s field of view I have a less distorting combination. And look at the Raynox – this lens has a lot less distortion for a quarter the price.

The Cavision 0.5x is a nice powerful converter though not without its faults. It has an 82mm filter thread and a 58mm attachment thread. It’s of three element, three group construction. It costs £144 complete with lens hood. The first two examples I looked at had specks of foreign matter between the elements and these were very obvious on footage shot with the lenses. The third lens was simply not as good as I expected it to be at the price so I asked for a forth sample to test. This lens was still disappointing although it gives remarkably little distortion for a powerful 0.5x, and for this I can forgive it some of its failings. It weighs in at 300g and the lens caps are useless, both of them falling off in warm weather. It comes in a leatherette draw-string case and has an 82mm filter thread. There’s a very good 4:3.5 aspect ratio hood that clamps to the outer diameter. Why not 4:3 Cavision?

At f2.4 the centre is as sharp as the Century, but the edges are way behind. By f11 the edges are better but diffraction has meant the snap has gone from the centre definition and colour fringing is most noticeable. Overall it’s better at f11 than at f2. There’s so much vignetting of the full DV frame that once cropped the 0.5x converter is more like a 0.6x. At full telephoto the performance is good at f5.6 and at this point the edges have sharpened up as well. www.cavision.com for more information.

The Raynox 0.66x is of three element, three group construction and sells for just under £100. It has a plastic box to keep it in, has a front lens cap that clips on securely and a rear cap that’s feeble, and weighs in at a lightweight 190g. The coating is nowhere near as good as on the Cavision and the Century, and hooding is recommended. It has a 72mm filter thread so this is not difficult to do. This Raynox is the only lens that you can use successfully as a converter for your 35mm still camera, where it handsomely outperforms all the rest. It’ll convert your 28mm f2.8 lens into an 18.5mm f2.8 lens with ease.

The instructions warn against using this lens past the half-way point on your zoom but I did some tests at full telephoto to check it out. Sure enough at full telephoto the image is decidedly soft and is covered with a veiling flare that is reminiscent of the effect given by the better soft focus screens. The effect is very aperture sensitive and at f4 it’s quite sharp in the middle of the frame with very soft edges. At f11 it’s soft all over and gives quite appealing portraiture shots.

At mid zoom it gives pincushion distortion but much better sharpness except right in the corners, and at wide it’s really a very good lens except that it vignettes the very corners of the frame. Overall it’s the best value for money here as its centre definition is indistinguishable from the VX2000 on its own.

tom.

[Frank Granovski]

Tom, does this Century have 37mm threads?

I recall a local pro shop and customer here doing a test with a number of wides, including a Century, for the TRV950 and their conclusion was the Tiffen was the sharpest.

[Tom Hardwick]

My tests were all carried out on, and are only applicable to, a VX2000 Frank, so you'd have to check the Century web-site for fittings available.

[Frank Granovski]

So then the "best" wide for the VX2000's thread size is this Century, but you cannot assume another model made by Century will be just as good.

[Boyd Ostroff]

Jan: Thanks for the e-mail that you sent, but I stupidly managed to delete it before responding!

Regarding the Titanium .45x lens, no I haven't had a chance to do any real testing of it, although it's something I've wanted to do for awhile. I'll try to take a few minutes during the coming week to shoot some example shots and put them online for all to see. Despite the holidays, things are rather busy at work here...

[Jan Roovers]

Today I got more encouraging results.
The sun was there shortly and
I shot a very short video zooming fom wide to tele.
I did not use a tripod, which can bee seen in tele :-)

This shot is in MPEG full resolution to be able to examine the resolution. So it is a large file: 11,5Mb I uploaded it temporarely for your convenience.

In between I added another shot in full wide. The link is on the page.

[Chris Long]

Wow, Jan, I think it looks quite nice. I think I'll be happy with it--thanks for posting the clips!

Were these shot in 16:9?

[Jan Roovers]

Chris, yes they were shot in 16x9.

I have uploaded them specially for you, because you will get the lens for Christmas. I am also very happy with the new shots. That is where I bought this lens for. I think you can look forward to a nice present that to my opinion is worth every penny. In DV and in practise the results can be very satisfying. Initially i doubted like you did, but yesterday I made some more quick test (in a hurry) that were very satisfying also. After Christmas I will take some more testshots.

One question remains: I have the idea that the depth of field is less than without the convertor, while I expected that it should be bigger.
Who can tell me more about that? Is that the behaviour of the convertor instead of a real widelens? If so, one can may be profit by it. Tom what is yr experience?

One thing is sure to me, the lens needs some practical experimenting to get known with its behaviour and to know how to get optimal results: lightning conditions, zoom, focus, diaphragm, lenshood. I think Tom is very right; they all play there role, worth while to play with them.

Chris, I am looking forward to your experiences with the lens and will be glad to share them with you.
Wideangle convertors seem to be a very interesting and challenging matter.

PS: With the shots I had the standard distancering 37mm to 37 mm attached. As you can see there was no visible vignetting. That is what i wanted to know.

[Tom Hardwick]

Adding a wide-angle converter actually does reduce the focal length Jan, so that the depth of field increases for any given aperture at any given focused distance. Don't forget though that the PDX10 lies when you push the "Display" button on replay, and I paste here a paragraph from my road test:

"To compound the injury, the 'Display' is very unreliable. The word ‘manual’ will appear on replay when you’ve selected a shutter speed but left the aperture on automatic. When you shoot at full telephoto and rewind to see what settings the camera used, it will often tell you that you shot at 1/60th sec and +18dB and f1.6 - yet at full telephoto the maximum aperture is only f2.8 - a good one and a half stops slower. To have the data shown in the viewfinder requires that you push Display, then touch FN on the touch screen, followed by Page 2, Data Code, Cam data, OK and then Exit. Having got there you’re none the wiser really because the code doesn’t record all the different ND settings you – or the automation - have dialled in. The camera also denotes automatic white balance as ATW rather than the more familiar AWB."

My guess is that the softer edges caused by using the w/a converter are making you think the DOF has been reduced Jan. Yes, you'll see there are losses, but the reason I love widies and have lots of them is the perspective control they give me. Love it!

tom.

[Jan Roovers]

Chris,

How is your convertor? What are your experiences?

I am curious to hear your results!


Jan