If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Center out of focus
Slides projected onto screen were sharp but the center of all the images
were out of focus. I asked the projectionist to adjust for the out of = focus and problem went from bad to worst. Instead of the center being a = problem the lower half the images were out of focus and the top half in focus. = My eyes teared like crazy during this whole time. Anyone familiar with image projection to comment about this strange out of focus problem? |
#2
|
|||
|
|||
mark_digital wrote:
Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of focus and problem went from bad to worst. Instead of the center being a problem the lower half the images were out of focus and the top half in focus. My eyes teared like crazy during this whole time. Anyone familiar with image projection to comment about this strange out of focus problem? Sounds to me like the slide carrier is no longer perpendicular to the rear of the lens. Either the carrier or the lens is fubar'd. -- jer email reply - I am not a 'ten' |
#3
|
|||
|
|||
"mark_digital" wrote in message ... Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of focus and problem went from bad to worst. Instead of the center being a problem the lower half the images were out of focus and the top half in focus. My eyes teared like crazy during this whole time. Anyone familiar with image projection to comment about this strange out of focus problem? Hi Mark Sounds like it could be a heat problem where the slide is not mounted in glass and buckles under heat from the projector's lamp. I always use glass slides because I learned the hard way during a rather critical presentation. Regards Martin |
#4
|
|||
|
|||
"mark_digital" wrote in message ... Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of focus and problem went from bad to worst. Instead of the center being a problem the lower half the images were out of focus and the top half in focus. My eyes teared like crazy during this whole time. Anyone familiar with image projection to comment about this strange out of focus problem? Hi Mark Sounds like it could be a heat problem where the slide is not mounted in glass and buckles under heat from the projector's lamp. I always use glass slides because I learned the hard way during a rather critical presentation. Regards Martin |
#5
|
|||
|
|||
On Sun, 17 Oct 2004 06:47:56 -0400, "mark_digital"
wrote: Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of focus and problem went from bad to worst. Instead of the center being a problem the lower half the images were out of focus and the top half in focus. My eyes teared like crazy during this whole time. Anyone familiar with image projection to comment about this strange out of focus problem? It's been a long time since I've projected, but here goes... Slides are, by their very nature, not rigid; they are not kept in a flat plane unless you pop fior some pretty expensive slide holders. TYhe slides themselves are not held rigidly in the projector; they can be off kilter to the lens/screen. These add up to a projection system that will show the image that's only sharp in some areas, unless you want to spend a lot of money on the really good stuff. Bill Funk Change "g" to "a" |
#6
|
|||
|
|||
"mark_digital" writes:
Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of focus and problem went from bad to worst. Instead of the center being a problem the lower half the images were out of focus and the top half in focus. My eyes teared like crazy during this whole time. Anyone familiar with image projection to comment about this strange out of focus problem? The screen wasn't parallel to the slide. -- David Dyer-Bennet, , http://www.dd-b.net/dd-b/ RKBA: http://noguns-nomoney.com/ http://www.dd-b.net/carry/ Pics: http://dd-b.lighthunters.net/ http://www.dd-b.net/dd-b/SnapshotAlbum/ Dragaera/Steven Brust: http://dragaera.info/ |
#7
|
|||
|
|||
"mark_digital" writes:
Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of focus and problem went from bad to worst. Instead of the center being a problem the lower half the images were out of focus and the top half in focus. My eyes teared like crazy during this whole time. Anyone familiar with image projection to comment about this strange out of focus problem? The screen wasn't parallel to the slide. -- David Dyer-Bennet, , http://www.dd-b.net/dd-b/ RKBA: http://noguns-nomoney.com/ http://www.dd-b.net/carry/ Pics: http://dd-b.lighthunters.net/ http://www.dd-b.net/dd-b/SnapshotAlbum/ Dragaera/Steven Brust: http://dragaera.info/ |
#8
|
|||
|
|||
"mark_digital" writes:
Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of focus and problem went from bad to worst. Instead of the center being a problem the lower half the images were out of focus and the top half in focus. My eyes teared like crazy during this whole time. Anyone familiar with image projection to comment about this strange out of focus problem? The screen wasn't parallel to the slide. -- David Dyer-Bennet, , http://www.dd-b.net/dd-b/ RKBA: http://noguns-nomoney.com/ http://www.dd-b.net/carry/ Pics: http://dd-b.lighthunters.net/ http://www.dd-b.net/dd-b/SnapshotAlbum/ Dragaera/Steven Brust: http://dragaera.info/ |
#9
|
|||
|
|||
"mark_digital" writes:
Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of = Are you talking about film? This being rpd and you being mark_digital, I just want to clear that up. Anyone familiar with image projection to comment about this strange out of focus problem? Slide film has a well-known characteristic: the film is not flat. Without knowiing what specifically you're referring to (film? digital images?), I'll guess that the film was particularly bowed. Sometimes heat causes the film to pop into a greater curve as the film expands, but is held in place at the edges by the slide mount. This often happens when one slide is held in front of the projection lamp for longer viewing pleasure, and the previously in focus image dissolves into fuzz. If this is film, the frames may have been sloppily framed, the screen and the projector may not have been aligned (either the projector was not at 90 degrees to the screen or the screen was above or below the projector or both), or a combination of the two. -- Philip Stripling | email to the replyto address is presumed Legal Assistance on the Web | spam and read later. email to philip@ http://www.PhilipStripling.com/ | my domain is read daily. |
#10
|
|||
|
|||
"mark_digital" writes:
Slides projected onto screen were sharp but the center of all the images were out of focus. I asked the projectionist to adjust for the out of = Are you talking about film? This being rpd and you being mark_digital, I just want to clear that up. Anyone familiar with image projection to comment about this strange out of focus problem? Slide film has a well-known characteristic: the film is not flat. Without knowiing what specifically you're referring to (film? digital images?), I'll guess that the film was particularly bowed. Sometimes heat causes the film to pop into a greater curve as the film expands, but is held in place at the edges by the slide mount. This often happens when one slide is held in front of the projection lamp for longer viewing pleasure, and the previously in focus image dissolves into fuzz. If this is film, the frames may have been sloppily framed, the screen and the projector may not have been aligned (either the projector was not at 90 degrees to the screen or the screen was above or below the projector or both), or a combination of the two. -- Philip Stripling | email to the replyto address is presumed Legal Assistance on the Web | spam and read later. email to philip@ http://www.PhilipStripling.com/ | my domain is read daily. |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
DSLR focus screens | Stacey | Digital Photography | 32 | September 2nd 04 06:18 PM |
how close is infinite focus? | Lazarus Long | Digital Photography | 74 | August 13th 04 06:55 PM |
Focus trouble | Luc Brentener | Digital Photography | 2 | July 13th 04 05:20 AM |
Rollei 6x6 projector focus | [email protected] | Other Photographic Equipment | 0 | December 2nd 03 12:27 AM |