DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Canon XL1S / XL1 Watchdog (https://www.dvinfo.net/forum/canon-xl1s-xl1-watchdog/)
-   -   Canon 3x wide angle lens questions (https://www.dvinfo.net/forum/canon-xl1s-xl1-watchdog/31641-canon-3x-wide-angle-lens-questions.html)

Nick Glenister July 31st, 2002 08:06 AM

Thanks for the advice, i'll search the forum later.

I like the idea of using the ef adapter with a 400mm lens to get the 2800mm as i have an interest in wildlife filming, was hoping one day to go on safari and take the XL1 with me and 2800mm would sound very useful.


Thanks


Nick

Dylan Couper August 7th, 2002 10:27 PM

3x lens focus issue
 
The autofocus on my 3x lens doesn't work up close. At about a foot away, either set on AF, or using the push AF with AF off, it will focus in/out/in/out very quickly, like maybe 3 times a second? Manual focus works fine, and AF works fine when slightly further back. Anyone else have this "feature"?

Daniel Chan August 7th, 2002 10:36 PM

Focus problem
 
Dylan,

While I can't give you a technical answer, from what I understand after using both the 16x ISII and the 3X, I think it has something to do with their ability to get depth of field.

I had the same problem with close up focus fron the 3X that's because it has the capability to get great depth of field fron great range and distance. I tried to play with the depth focus and got great footage shooting two objects that are about 15 meters apart. However when I tried to play with the depth focus in my tiny apartment, everything in the background looks focused and nothing looks focused up close.

You'll get similar problems from the 16X ISII they just don't seem to have the ability to focus when the object is extremely close to the lens.

That probably didn't answer your question but that's why I found from my experience.

Daniel

Jeff Donald August 8th, 2002 04:07 AM

All lenses have a minimum focus distance. It is measured from the CCD to the nearest object the lens can focus on. The minimum focus distance for the 3x is .5meters or about 20 inches. This is a limitation of lenses and optics and is controlled by Laws of Physics. This should not be considered a defect. It is also not related Depth of Field. Screw on close-up filters are available if you need to focus closer than 20 inches.

Jeff

Dylan Couper August 8th, 2002 10:34 AM

Jeff, do you mean the focus or auto-focus?
I'm only talking about the AF, the manual focus works fine at the minimum (I thought a foot, but I guess it might have been 20"), but the autofocus hunts in and out constantly and won't work.

Jeff Donald August 8th, 2002 11:01 AM

The distance is measured from the chip (CCD's) not the front element of the lens. Minimum focus distance is the same if your using AF or manual focus. AF will hunt and search in low contrast situations, when subject is very small and can't be picked out from background, low light levels etc. So, the bottom line is, this not unusual for macro work. Try increase the light level, putting something larger in place of the small subject (then remove and shoot once focus is locked) use an object with strong vertical lines (AF works better with vertical lines). Or you could just focus manually.

Jeff

Dylan Couper August 9th, 2002 01:44 AM

I'll just focus manually. :)

Thinking back to location, the lighting was very low on the close up object, even though the rest of the room was well lit. I know the amount of light makes a big difference to the AF, but I just didn't think about it at the time. That's probably why it was behaving like that.
Thanks!

Norman Woo August 15th, 2002 02:17 PM

0.6 Wide Angle (Century Optics) on the Canon 3X Wide Angle Zoom
 
Folks

I have an XL-1 with the standard 16x Lens. I also have the 0.6 Wide Angle from Century Optics attachment that goes in front of the 16X lens. Can this be also attached in front of a 3X wide Angle Zoom to create an even wider angle?

Thanks

Paul Sedillo August 15th, 2002 06:27 PM

Re: got my 3x lens today
 
<<<-- Originally posted by Dylan Couper : After debating between a wide angle converter, or the 3x lens, I chose the lens. If for nothing else, it's got a great re-sale value on Ebay. :)
-->>>

Hey Dylan,

As you know I picked up Jim's 3x lens. I wanted to get your feedback on your 3x lens. Have you had a chance to shoot with it, if so tell me your impression.

Paul

Don Berube August 15th, 2002 10:25 PM

Yes, I am pretty sure it will work fine without any vignetting, since it is a .6x adaptor.

Same thread size on the 3x as the 16x IS lens.

You may experience some vignetting if you place a sunhood on the front of the CO adaptor - I could try this out next week at WEVA and let you know.

- don

Dylan Couper August 16th, 2002 12:59 AM

It's a great lens, I've used mine extensively and am very happy with it. The only drawback is it doesn't have quite enough zoom. 5x would probably do it, but 3x is just a little short for a lot of things, expecially if you don't have time to change back to the 16x.
Still, it's a valuable toy, er.. tool to have.

Paul Sedillo August 16th, 2002 04:50 AM

<<<-- Originally posted by Dylan Couper : It's a great lens, I've used mine extensively and am very happy with it. The only drawback is it doesn't have quite enough zoom. 5x would probably do it, but 3x is just a little short for a lot of things, expecially if you don't have time to change back to the 16x.
Still, it's a valuable toy, er.. tool to have. -->>>

I saw mention that at full zoom (or was it the other way around) that there is a bit of a focus problem around the edges of the frame. Have you found that to be true?

Now the next lens you need to get is the 16x Manual Servo Lens. If you don't already have it!

Don Palomaki August 16th, 2002 08:57 AM

Lack of zoom range: that points to the main benefit of a full zoom through converter, such as the Century. You get the 16x zoom range - and a bit more weight on the front of the 16x lens to go with it.

Some folks even run their GL1 with a 0.65x or 0.7x adapter left on full time.

Paul Sedillo August 16th, 2002 02:28 PM

<<<-- Originally posted by Don Palomaki : Lack of zoom range: that points to the main benefit of a full zoom through converter, such as the Century. You get the 16x zoom range - and a bit more weight on the front of the 16x lens to go with it.

Some folks even run their GL1 with a 0.65x or 0.7x adapter left on full time. -->>>

Don,

Forgive my lack of knowledge, but does adding the converter distort the image?

Dylan Couper August 20th, 2002 07:10 PM

Regarding converters, there are several different makes on the market. I believe someone said they will give you distortion once you zoom past a certain point. If you do a search through this section, you'll probably find the post.

As far the the 16x manual goes, I think I'd probably opt for the 14x manual. I'd rather have on-lens iris control, and an extra $500 in my pocket. But if a good deal on the 16x lens came up, I'd probably take it. :)

Oh, I haven't noticed any soft focus at full zoom on my 3x.


All times are GMT -6. The time now is 07:14 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2019 The Digital Video Information Network