| Author |
Message |
    
Btgc
Tinkerer
Username: Btgc
Post Number: 16
Registered: 01-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 18, 2009 - 02:37 pm: | 
|
Hello,
googled around, but haven't got sure if removing and attaching lens mount on SLR impacts focusing.
I have Ricoh SLR with broken lens release knob. While I can change lenses with some fine job, would like to find replacement part and swap it. For this I need to remove lens mount.
As position of mount makes sense, just wanted to get opinions on how usually distance between mount and film plane is adjusted.
Thank you in advance. |
Mndean
Tinkerer
Username: Mndean
Post Number: 134
Registered: 08-2007
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 18, 2009 - 03:38 pm: |
|
The answer is that it depends on the camera manufacturer. Generally it shouldn't, but some older cameras used shims to correct for accurate focal plane distances, most others corrected for the FP distance by making it a bit oversized and milling the lens mount pads to fit. I'd guess with a Ricoh it's the latter and it won't be a problem to remove the lens mount, but I'd wait to hear from someone with Ricoh experience to weigh in on it. |
Bossman
Tinkerer
Username: Bossman
Post Number: 38
Registered: 02-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 18, 2009 - 08:30 pm: |
|
Removing the lens mount will have absolutely no effect on focus unless you lose any shims (see Mndean) or put them back in the wrong position. Put a drop of paint or cement on screw threads when replacing and tighten real well. |
John_shriver
Tinkerer
Username: John_shriver
Post Number: 41
Registered: 12-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, March 19, 2009 - 07:57 pm: |
|
If the new mount isn't the same thickness as the old one, you will create a focusing error. |
Rick_oleson
Tinkerer
Username: Rick_oleson
Post Number: 840
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, March 19, 2009 - 08:53 pm: |
|
You won't create a focusing error per se; you may create a situation where the camera either won't focus to infinity or will focus past it, but unless you also manage to move the mirror or focusing screen, you will still see the same image in the viewfinder that your film will see - so what looks sharp in the finder will still be sharp on the film. |
Btgc
Tinkerer
Username: Btgc
Post Number: 18
Registered: 01-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, March 21, 2009 - 02:12 pm: |
|
Thank you all for replay! Seems it's relatively safe. I'll put back old mount, lens release lever is plastic part under mount.
>you may create a situation where the camera
>either won't focus to infinity or will focus past it
yes, this is more appropriate description of what I wanted to ask for!
Probably I'll go for this, mainly to see how FP<->mount distance is enforced to be within limit.
btw how SLR's synchronize FP and VF images - adjusting at mount or mirror/focusing screen ?
So far I have dealt only with fixed lens RF's (check/set lens and then adjust RF), SLR is all new thing. |
