Century .7 wide angle question.... at DVinfo.net

Marty Hudzik · October 4th, 2004, 08:09 AM

This is for anyone who has used this unit on the XL1 series. I am aware that currently it will not work on the XL2 but I spoke with Century and they will have a new one and a fix for existing units in 30-60 days. So here is my question.

Does the focus adjustment work just like it does on the normal lens when you are zooming? What I mean to say is that if I zoom in, get critical focus, then pull out does it retain focus properly?

I currently have the .6x that is not zoom through and it works properly. But the relationship between focus and zoom are screwed up! In other words I have to refocus completely everytime I do even a minor zoom. If I zoom as far as I can in the range of this adapter, focus, then zoom out it goes all out of focus. Almost like a backfocus issue but caused by the strange relationship between the adapter and the Canon glass.

This makes using the .6x a pain as I can really only do shots that require no zoom. Since I am doing a moderate ammount of live event footage there are times that I need the wide angle adapter to get the shot but I may also need to zoom " a little bit" here and there to achieve the shot composition I want. And the minute I do even a minor zoom the focus is off and I have to compensate which ruins the shot. Without the adapter the lens behaves like this. IF I need to zoom a little to get a little tighter shot the focus stays fine. I have to zoom a lot to get to a point that I have to refocus.

Does the .7x WA zoom through perform the same as the .6x? I hope not.

This will determine if I return the .6x and get the .7x when it is released for the XL2.

Thanks!

Chris Hurd · October 4th, 2004, 08:46 AM

The Century .7x is in fact a full-zoom-through adapter.

Marty Hudzik · October 4th, 2004, 09:32 AM

<<<-- Originally posted by Chris Hurd : The Century .7x is in fact a full-zoom-through adapter. -->>>

I understand that. But does it behave exactly as if there was no adapter on there at all? In regard to how it focuses that is.

I am aware that the .6x is not zoom through but it has partial zoom. In that "partial" range the focus behaves really screwy. If I am full wide and zoom a little....like 1x the focus can get thrown way out....I mean way, way way out. I focus manually and I am okay. If I pull back a little it goes way out again....so I have to focus manually. It behaves like this through the entire "focusable range". However there is a point that it is impossible to achieve focus. That point is outside of the "Partial"area. That I am willing to accept. But the weird nature that shows up in the usable range, is non-intuitive and is not like focusing with any other lens.

This is specifically what I am inquiring about. With the .7x does focusing completely behave itself?

Dean Sensui · October 4th, 2004, 05:08 PM

It behaves exactly like a normal zoom lens. No problem with focus shifting, as long as the lens' back-focus is properly set.

I have one of these .7 WA adapters on my manual 16x lens and seldom take it off.

Dean Sensui
Base Two Productions.

Josh Bass · October 4th, 2004, 09:58 PM

Here's what I was told when I researched this topic. The 6x is a FIXED FOCAL LENGTH ADAPTER. Yes, it is partial zoom through (8x, I believe), but what they DON'T tell you is it's meant to be zoomed through using AUTOFOCUS ONLY, otherwise, yes, you will have to readjust every time you zoom with that thing on. I believe it even says that on ZGC's site, somewhere.

The .7x is meant to be FULLY zoomthrough, meaning that you can go all the way to the end of the zoom range with it and retain focus, which I ASSUME means if you critically focus, it'll hold throughout its zoom range, like any lens is supposed to.

Marty Hudzik · October 5th, 2004, 12:52 PM

Here is what I found out by experimenting. If I have the .6x adapter on the 20x lens and zoom out to full wide and set the focus, I can then zoom about 7-8x and still be in perfect focus. This is in manual focus mode. So i never have to touch the ring. Once I start to go beyond 8x (approx) it starts to lose focus. I can however manually bring it into focus in this area just beyond 8x. However once I focus in that little range if I zoom back out it loses focus.

So essentially it stays in perfect focus through 8x and there is a little range beyond that where you can still get a good focus. However if you use this range you can't zoom out without losing focus again. Also...beyond that little range it is impossible to get it to focus. So I guess it works like it should and as long as you don't need telephoto in your shot you are okay.

Also.....a tip for anyone using this kind of adapter. Use the memory feature of the 20x lens and set it to zoom. Then you zoom in the maximum ammount before you lose focus and set the memory for that point. The XL2 now puts a little yellow square on the zoom indicator in the viewfinder. You can use this as a guide to know when to stop zooming so your shot doesn't go out of focus. It works very nice.

Now.....if someone can help me make a makeshift lens hood for the .6x that allows for quick removal I'd appreciate it!

Thanks!

October 4th, 2004, 08:09 AM	#1
Marty Hudzik Trustee Join Date: Jul 2004 Location: Canton, Ohio Posts: 1,771	Century .7 wide angle question.... This is for anyone who has used this unit on the XL1 series. I am aware that currently it will not work on the XL2 but I spoke with Century and they will have a new one and a fix for existing units in 30-60 days. So here is my question. Does the focus adjustment work just like it does on the normal lens when you are zooming? What I mean to say is that if I zoom in, get critical focus, then pull out does it retain focus properly? I currently have the .6x that is not zoom through and it works properly. But the relationship between focus and zoom are screwed up! In other words I have to refocus completely everytime I do even a minor zoom. If I zoom as far as I can in the range of this adapter, focus, then zoom out it goes all out of focus. Almost like a backfocus issue but caused by the strange relationship between the adapter and the Canon glass. This makes using the .6x a pain as I can really only do shots that require no zoom. Since I am doing a moderate ammount of live event footage there are times that I need the wide angle adapter to get the shot but I may also need to zoom " a little bit" here and there to achieve the shot composition I want. And the minute I do even a minor zoom the focus is off and I have to compensate which ruins the shot. Without the adapter the lens behaves like this. IF I need to zoom a little to get a little tighter shot the focus stays fine. I have to zoom a lot to get to a point that I have to refocus. Does the .7x WA zoom through perform the same as the .6x? I hope not. This will determine if I return the .6x and get the .7x when it is released for the XL2. Thanks!

October 4th, 2004, 08:46 AM	#2
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	The Century .7x is in fact a full-zoom-through adapter. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

October 4th, 2004, 09:58 PM	#5
Josh Bass Slash Rules! Join Date: Apr 2002 Location: Houston, Texas Posts: 5,472	Here's what I was told when I researched this topic. The 6x is a FIXED FOCAL LENGTH ADAPTER. Yes, it is partial zoom through (8x, I believe), but what they DON'T tell you is it's meant to be zoomed through using AUTOFOCUS ONLY, otherwise, yes, you will have to readjust every time you zoom with that thing on. I believe it even says that on ZGC's site, somewhere. The .7x is meant to be FULLY zoomthrough, meaning that you can go all the way to the end of the zoom range with it and retain focus, which I ASSUME means if you critically focus, it'll hold throughout its zoom range, like any lens is supposed to. __________________ The Bass' camerawork The Bass on IMDB

October 4th, 2004, 09:32 AM	#3
Marty Hudzik Trustee Join Date: Jul 2004 Location: Canton, Ohio Posts: 1,771	<<<-- Originally posted by Chris Hurd : The Century .7x is in fact a full-zoom-through adapter. -->>> I understand that. But does it behave exactly as if there was no adapter on there at all? In regard to how it focuses that is. I am aware that the .6x is not zoom through but it has partial zoom. In that "partial" range the focus behaves really screwy. If I am full wide and zoom a little....like 1x the focus can get thrown way out....I mean way, way way out. I focus manually and I am okay. If I pull back a little it goes way out again....so I have to focus manually. It behaves like this through the entire "focusable range". However there is a point that it is impossible to achieve focus. That point is outside of the "Partial"area. That I am willing to accept. But the weird nature that shows up in the usable range, is non-intuitive and is not like focusing with any other lens. This is specifically what I am inquiring about. With the .7x does focusing completely behave itself?

October 4th, 2004, 05:08 PM	#4
Dean Sensui Inner Circle Join Date: Oct 2001 Location: Honolulu, HI Posts: 2,054	It behaves exactly like a normal zoom lens. No problem with focus shifting, as long as the lens' back-focus is properly set. I have one of these .7 WA adapters on my manual 16x lens and seldom take it off. Dean Sensui Base Two Productions.

October 5th, 2004, 12:52 PM	#6
Marty Hudzik Trustee Join Date: Jul 2004 Location: Canton, Ohio Posts: 1,771	Here is what I found out by experimenting. If I have the .6x adapter on the 20x lens and zoom out to full wide and set the focus, I can then zoom about 7-8x and still be in perfect focus. This is in manual focus mode. So i never have to touch the ring. Once I start to go beyond 8x (approx) it starts to lose focus. I can however manually bring it into focus in this area just beyond 8x. However once I focus in that little range if I zoom back out it loses focus. So essentially it stays in perfect focus through 8x and there is a little range beyond that where you can still get a good focus. However if you use this range you can't zoom out without losing focus again. Also...beyond that little range it is impossible to get it to focus. So I guess it works like it should and as long as you don't need telephoto in your shot you are okay. Also.....a tip for anyone using this kind of adapter. Use the memory feature of the 20x lens and set it to zoom. Then you zoom in the maximum ammount before you lose focus and set the memory for that point. The XL2 now puts a little yellow square on the zoom indicator in the viewfinder. You can use this as a guide to know when to stop zooming so your shot doesn't go out of focus. It works very nice. Now.....if someone can help me make a makeshift lens hood for the .6x that allows for quick removal I'd appreciate it! Thanks!