I've had my dVX about a week. The zoom has a pronounced hitch at each end of the zoom. I need to back off the end several mm to get past the hitch to get a smooth zoom. Is this common with the DVX? How much can I expect from $3500? Happens with on board zoom control or my Zoe control.
glich in zoom
- Thread starter xort
- Start date
J.R. Hudson
Spirit Animal
Re: glich in zoom
I havent experienced this problem but I never use AUTO ZOOM at that. Can you describe the HITCH?
I havent experienced this problem but I never use AUTO ZOOM at that. Can you describe the HITCH?
Re: glich in zoom
When I switch to "servo", I can feel and hear a mechanical click as the servo drive engages with the mechanical zoom. If I then gently move the zoom ring, I can feel a slight wiggle and see a slight shift in the zoom. I believe this is backlash (in other words, slop) in the drive mechanism. So as I reverse my zoom direction, there is a very brief lag in the zoom as the backlash is taken up. When I use the zoom manually, I don't feel any backlash so it's not in the lens itself. Is this what you're seeing?
If you're planning a servo zoom, you might momentarily zoom in the directrion that you plan to zoom to take up any backlash before the shot. It seems to me that the drive train could be more precise but I don't find it a big problem in practice. I like having the option of a mechnical zoom.
-Dan
When I switch to "servo", I can feel and hear a mechanical click as the servo drive engages with the mechanical zoom. If I then gently move the zoom ring, I can feel a slight wiggle and see a slight shift in the zoom. I believe this is backlash (in other words, slop) in the drive mechanism. So as I reverse my zoom direction, there is a very brief lag in the zoom as the backlash is taken up. When I use the zoom manually, I don't feel any backlash so it's not in the lens itself. Is this what you're seeing?
If you're planning a servo zoom, you might momentarily zoom in the directrion that you plan to zoom to take up any backlash before the shot. It seems to me that the drive train could be more precise but I don't find it a big problem in practice. I like having the option of a mechnical zoom.
-Dan
Re: glich in zoom
Xort,
The servo on these cams isn't the greatest (as you've noticed), you need to pre-load the zoom...zoom out just a bit before your "real" zoom as Teledan indicated. The rough spot is right at the beginning. The DVX apparently has a limited number of steps (3 speeds has been mentioned) so even the Zoe doesn't have a lot to work with. However, once you get past the bump, you really can do a smooth 20-30 second zoom.
Ken
Xort,
The servo on these cams isn't the greatest (as you've noticed), you need to pre-load the zoom...zoom out just a bit before your "real" zoom as Teledan indicated. The rough spot is right at the beginning. The DVX apparently has a limited number of steps (3 speeds has been mentioned) so even the Zoe doesn't have a lot to work with. However, once you get past the bump, you really can do a smooth 20-30 second zoom.
Ken
Mitch_Ives
Well-known member
Re: glich in zoom
[quote author=xort link=board=Links;num=1090028741;start=0#0 date=07/16/04 at 18:45:41]I've had my dVX about a week. The zoom has a pronounced hitch at each end of the zoom. I need to back off the end several mm to get past the hitch to get a smooth zoom. Is this common with the DVX? How much can I expect from $3500? Happens with on board zoom control or my Zoe control.[/quote]
Yes, there is. It is really bad with the 100, and much improved with the 100A. I find the 100A is acceptable, but like others have recommended, load the zoom first.
I have also noticed a similar phenomenon occur during a zoom/pan where there is a an object in the frame that is blown-out (I live in Arizona). It appears that the DSP is being over taxed. I need to run some tests with the OIS off and see whether that is a factor?
[quote author=xort link=board=Links;num=1090028741;start=0#0 date=07/16/04 at 18:45:41]I've had my dVX about a week. The zoom has a pronounced hitch at each end of the zoom. I need to back off the end several mm to get past the hitch to get a smooth zoom. Is this common with the DVX? How much can I expect from $3500? Happens with on board zoom control or my Zoe control.[/quote]
Yes, there is. It is really bad with the 100, and much improved with the 100A. I find the 100A is acceptable, but like others have recommended, load the zoom first.
I have also noticed a similar phenomenon occur during a zoom/pan where there is a an object in the frame that is blown-out (I live in Arizona). It appears that the DSP is being over taxed. I need to run some tests with the OIS off and see whether that is a factor?