Tim Sassoon compares XL lenses in DV Magazine

[Chris Hurd]

In this month's edition of DV Magazine (July 2006), Tim Sassoon has a fairly comprehensive article which compares the stock 20x HD lens with the manual 16x SD lens on the XL H1. The article describes how he shot an ISO12233 widescreen res chart at a variety of focal lengths from full wide to full tele and a variety of aperture values with both lenses. Tim provides an excellent technical explanation of the various real-world differences between these lenses, and how aperture values affect chromatic abberation and other distortions. It's a very well written piece. If you're not a subscriber to DV Magazine (it's free if you fill out a marketing info form on the CMP site, or you can find it in most of the larger chain bookstores), then you can catch this article on the dv.com site in the near future.

[Chris Hurd]

The near future is already here. Register for free at dv.com to read the online version of Tim's article.

[Marty Hudzik]

Well that is kinda disapointing to see. I didn't expect the lens to be so riddled with CA. I'd really like to see how it is on actual footage and not on a rez chart. I am sure it is there but maybe much less noticable.

Anyone have any actual images from the 16x lens vs. the 20x? I hope in real world use it is not that severe.

[Chris Hurd]

This weekend when I'm back at the house, I can give you some comparo images. Unless somebody else beats me to it before then (Pete?)

[Marty Hudzik]

I had been hearing such good things about the 16x manual on the H1 I picked one up used for a good price. I won't be actually getting my H1 until after I finish my move and have all the closing finanaces dealt with. So I will be staring at a lens with no camera! Until I read that article I was thinking I'd be saying "man is this gonna rock!" NOw I'm afraid I'll be saying....What kind of screwed up looking footage amd I gonna get with this?

Thanks!

[Pete Bauer]

Naw, sorry Chris, I'm super busy this week so won't be doing any shooting. Haven't even read Tim's article yet. I do still have a some homemade static rez chart shots on my personal web site that compare the 20x HD, 20x SD, and the 3x:

http://www.geosynchrony.com/scratchpad.htm

Hmmm, I see it is getting to be a while since I updated my web site. Every week I think next week will be less busy. So maybe I'll update my site next week. ;-)

[John Richard]

Re: Tim Sassoon's 20X vs 16X lense article - excellent study but I have to disagree with his report that the 20x servo focus is not repeatable. We have our H1 w/20x lense set up with a Chroziel follow focus and find no trouble setting focus marks and pulling repeatable focus. Is anyone else having trouble pulling focus to a mark?

[Robert Sanders]

Originally Posted by Marty Hudzik

Well that is kinda disapointing to see. I didn't expect the lens to be so riddled with CA. I'd really like to see how it is on actual footage and not on a rez chart. I am sure it is there but maybe much less noticable.

Anyone have any actual images from the 16x lens vs. the 20x? I hope in real world use it is not that severe.

Much ado about very little.

[Marty Hudzik]

Originally Posted by Robert Sanders

Much ado about very little.

Could you clarify?

[Robert Sanders]

I hate hate hate reviews based on charts, graphs and white papers. There are have been a million silly flame wars started over a statistic.

The real proof is in the pudding. Go out and rent a camera and rent a lens and shoot something REAL. Something characteristic of what you're going to use the system for. Then judge the equipment based on those results.

I've used the 3x SD lens on the H1 on several occassions with very pleasant results. If I listened to everyone on these boards or focused too much on a chart I would have never considered it. The consesus was the 3x lens is AWEFUL!

I have some footage posted on my blog using this "unacceptable" lens.

Panavision C-series anamorphic lenses suffer from extreme lens flaring, hyper breathing and fierce barrelling. There are cinematographers and director's to this day that still prefer shooting with those lenses because of their 'character' and 'flaws'. Those lense are FAR from perfect.

I guess what I'm saying is that absolute perfection in optics is not always the best solution. In the case of CA, it's about whether or not the lenses are affordable and still acceptable.

[Chris Hurd]

Originally Posted by Robert Sanders

I've used the 3x SD lens on the H1 on several occassions with very pleasant results. If I listened to everyone on these boards or focused too much on a chart I would have never considered it. The consesus was the 3x lens is AWEFUL!

That's partially my fault, and I'm here right now to take back everything I said about the 3x SD lens on the H1, and eat my words raw with a big helping of crow to boot.

Somewhere in the past -- I ain't gonna bother finding the thread -- I said I had briefly tested this combo and found the lens to be too soft, impossible to focus. I made a serious mistake! I had neglected to perform the Flange-Back operation, which properly sets back-focus for any XL series lens, a handy feature of the XL H1. No wonder my tests were soft! Everything I said about it at the time, is dead wrong. I'm going to re-post some 3x examples and show you guys just how good it is. Unless somebody wants to offer their own clips and stills -- I'm happy to host them here.

Lesson learned: always always perform the Flange Back adjustment when changing XL lenses (you can store a number of FB settings in the camera's memory too, a very useful feature of the XL H1).

Thanks Robert (how did I miss you at the XL H1 Road Show in Los Angeles?),

[Robert Sanders]

Thanks Chris. One of the first things my cinematographer did was take all three of our lenses and perform flange back procedures. Apparently the H1 remembers the lenses and readjusts itself according to which one is installed. Very clever of Canon to do this.

Now I don't want to give the impression that the 3x lens is perfect. It's far from it. And I haven't done any filmout tests or large scale projection of images produced with this lens. But based on viewing on a 23" cinema display and a 50" plasma, I'm very happy with the result.

Yes there is some softness in the far edges of the corners. But the rolloff is very even and nice. There is a little CA in high contrast areas (such as street lamps in the distance), but it's acceptable.

Again, I find the lens appropriate for some situations and I find the lens' quality to be commersurate with it's price.

[Jacques Mersereau]

Originally Posted by Chris Hurd

<EDIT>
Lesson learned: always always perform the Flange Back adjustment when changing XL lenses (you can store a number of FB settings in the camera's memory too, a very useful feature of the XL H1). ,

Okay, I am an idiot. This is the first I have heard of flange back adjustment.
Can you explain or direct me to a thread that covers this operation?

[Marty Hudzik]

I got my XL-H1 finally and was able to shoot a little with the 16x manual lens. It was indoors under normal house lighting so I had to have the iris wide open the entire time. I can say that the footage looked pretty darn good. I didn't notice any.....I repeat...any chromatic abberations at all....they may be there but a casual viewing showed none so most wouldn't notice it.

I didn't have time to compare to the 20x HD lens directly. The image may be slightly softer....maybe. In my opinion it still looked much sharper than my old HVX200 and performed like a frickin champ in this short "available light" test. The HVX would never have been able to deliver a good picture in this lighting without noise issues.

I am very happy with the H1 so far.

Thanks!

[Barlow Elton]

I had a feeling you'd like that combo, Marty! Now you can just get busy and not worry about resolution, noise or a "spongey, wet cabbage" lens.

Let us know how things go.

B