Half Inch Lens Test... Surprising Result!!

[Alister Chapman]

I finally recieved my Canon 20x HDGC half inch HD lens. So I spent about an hour this evening doing some quick (and rough) tests to see how it performances compared to my Canon YH19 half inch SD lens. Well here are the frame grabs.

http://www.ingenioustv.co.uk/clips/canonhdgc.zip
http://www.ingenioustv.co.uk/clips/canonyh19.zip
http://www.ingenioustv.co.uk/clips/canonhdchart.zip
http://www.ingenioustv.co.uk/clips/canonsdchart.zip

The exterior shots were at f5.6, 30mm
The chart shots at f2, 40mm

The chart is a computer printed chart on A4 photo paper so the resolution scales are inaccurate. Camera gain was -3db, Gamma 3, Detail set at the Sony default.

On the two exteriors it is very difficult to see any difference, the HD lens appears to have a little less CA. The chart is a little more revealing! If you look carefully at the resolution scales towards the center I think you can clearly see that the HD lens is just a bit sharper... BUT LOOK AT THE EDGES!!! YUK! The HD lens clearly has problems at the edges and in the corners. The SD lens is softer at the edges too, but not nearly as bad as the rather blurred HD lens. This should not be so. The HD lens is double the cost of the SD lens, yet it is very soft away from the center, I would expect the HD lens to at least match the SD lens. I'll try to do some more accuarte tests tomorrow with a bigger monitor to check the focus.

[Simon Wyndham]

You're right. The softening on the res chart on the HD lens is pretty horrendous.

And there does seem to be pretty much no difference between the two exterior shots too.

More tests would be good, but even if your focus was slightly out, the softening is pretty bad.

Would be interesting to check for straightness of verticals on miniumum zoom too to see how they compare.

[Hornady Setiawan]

thank you Alister.
This is very informative.
Can u also test sharpness with chart on different zoom lengths?
Maybe the softness is less apparent in diff zoom length?

And, does anyone here owns a Fuji HD lens? :)

[Greg Boston]

Originally Posted by Hornady Setiawan

And, does anyone here owns a Fuji HD lens? :)

Yes, I have the 18x5.5 1/2 HD lens on my F350.

-gb-

[Nate Weaver]

This is consistent with my lens shopping experiences too. I've been driving all over Burbank (where there's a lot of lenses for sale) and rolling off on charts where available, and just whatever is out the front door when a chart isn't available.

I seem to have found a Canon H series 1/2" lens that seems to be remarkably sharp throughout most of it's range, although it does soften up wide open. It is markedly better than the S series Fujis, and YH series Canons that are all over.

The other 1/2" SD lenses are mixed bags. All, at times and given the right subject matter, can fool the eye for an HD lens. The devil of course is in the details, and this is where they fail...they can't deliver a uniformly sharp image at all focus settings and throughout the zoom range. I believe this is more or less what you Alister have been saying all along, yes?

I would be the last person to spout off about conspiracy theories and the like, but is some of this why the manus keep MTF charts scarce?

[Alister Chapman]

I have done some further comparisons, the resulting frame grabs are here..

3x Jpegs in each zip file.

http://www.ingenioustv.co.uk/clips/canonhdgcnew.zip
http://www.ingenioustv.co.uk/clips/canonsdnew.zip

Test chart shot at 10mm focal length f2.8 plus 2x exterior shots at 6.7mm (approx on the HD lens which goes to 6.4) at f16 and f4.

My conclusion is that the Canon KH20x6.4 is sharper than the Canon YH19x6.7. Neither lens performs particularly well at f16, both perform best between f11 and f4. The difference between the two is fairly constant across the zoom range, both exhibit minor barrel distortion when fully wide. More open than f5.6 the KH20 HD lens becomes noticably soft at the edges and in the corners, more so than the YH19, past f2.8 it's blurred.

I guess this is kind of what I expected, with the exception of the very soft edges with the HD lens. The difference between the two lenses is not huge and in most cases the YH19 would (IMHO) pass for an HD lens.

The KH20 is better built than the YH19, less plastic and more metal, but I have to say that I am not yet convinced that it is worth the extra money. Compared to a 2/3 inch HD lens this is a pretty cheap lens, so to expect perfection is a bit much but the softness at the edges is cause for concern.

[Thierry Humeau]

After running into serious sharpness issues while shooting computer screens with a Fujinon HD 18x5.5, I too ran some tests on HD lenses available for XDCAM HD camcorder and am quite puzzled by the results. I tested 3 lenses, Fujinon XDCAM HD 1/2" lenses (18x5.5 and 13x3.3) and for the sake of it, a standard definition Canon lens (7.8x21) by shooting a lens sharpness chart of a 21" LCD monitor. The Canon SD lens yielded the best results....

See the screen grabs at:

www.telecamfilms.com/hdlenstests.html

Thierry

[Greg Boston]

Very interesting Thierry. I have felt that the Fuji 18x5.5 is kind of soft, but I don't have a lens file set up for it either. Have you done any lens files for these lenses to optimize their performance?

-gb-

[Thierry Humeau]

No, there are currently no lens files available for this lens and I dont' know really were to start to create one from scratch.... I assume the upcoming version of XDCAM HD firmware will include lens files for most 1/2" lenses currently available. In any case, I don't expect the poor performances of the Fujinon 5.5x18 to improve much by using different lens files. One thing I should note here is that I was informed by my contact at Sony that the Fujinon lens I now have is a pre-production model and that the production model has improved. I am hoping to have access to it soon.

Thierry.

[Hornady Setiawan]

Dear all in the know,
Will all 1/2" SD lens (fuji/canon for XDCAM SD) fit directly into the new XDCAM HD?

Regs,
hornady

[Alister Chapman]

All half inch SONY mount lenses should fit the XDCAM HD range. Lenses with a half inch Panasonic mount will not fit. Most of the sony lenses have a series of contact pins that electrically connect the lans to the camera, but a separate lens connector is also fitted to the camera body for 2/3inch lenses and lenses that use a cabled connection.

[Simon Wyndham]

Will all 1/2" SD lens (fuji/canon for XDCAM SD) fit directly into the new XDCAM HD?

The lenses used on XDCAM SD are all 2/3". So you'd need an adaptor to mount them to XDCAM HD.

[Brett Sherman]

I'm encouraged by your tests that I may be able to start out with an SD lens and then eventually upgrade to an HD lens. So I'd like to get some opinions.

First off, which YH19 lens are you using. There is a big price range from $2000-8000 for different ones.

I expect to be editing for the next couple years in SD. So am I better off getting an F330 and shooting in HD with a cheaper SD lens to allow future HD use of the video or buying a cheaper HDV camera with a built-in lens?

Also how does the 1/2" lens sizes convert to 35mm angles? I've always used 35mm to figure out wide/telephoto sizes. When it says 6.7-127mm what does that mean to 35mm sizes?

[Alister Chapman]

The lens SD I have been using is a Canon YH19x6.7.

I have been using the HD lens some more and there is a difference, but it is small and it is dependant on the focal length. It may be an option to buy a SD lens now and upgrade as funds allow, which is what I did.

To convert to 35mm equivalent focal lengths you multiply the 1/2" focal length by 5.46. So for example my 20x6.4 HD lens is the equivalent of a 35 to 698mm 35mm lens.

[Brett Sherman]

There are a few varieties of the YH19x6.7 lens, they are:

IRS for $8000
KTS for $4400 and
KRS for $2000

Are there significant quality differences between them?