Jump to content

focusing help


j_buck

Recommended Posts

this will be mby a silly question, so im sorry for it. but:

lately ive been shooting alot of LF, and i just got a 165mm f2.7 lens.

and I'm have big problems focusing if the subject is far.

 

the speed graphic viewfinder is too grainy if magnified alot.

 

would better groundglass help?

or a better loup? or some special tehnick?

 

ps. for loup i use my pentax 67 magnifier viewfinder and cheep loup from a shop.

Link to comment
Share on other sites

<p>Which vintage Speed Graphic do you have? They were introduced in 1912 and ended production in 1970.<br>

Top handle, pre anniversary, anniversary, pacemaker.<br>

You probably need a better loupe or a thorough cleaning of the ground glass. When focusing look at the image not the grain of the ground glass.</p>

Link to comment
Share on other sites

<p>Just use dishwasher soap and a soft brush.<br>

The ground glass and the loupe work in combination... so if your GG is too grainy, you may want a low power loupe, and viceversa.<br>

I have not used your lens, but I`d think a f2.7 lens wide open could not have a high contrast, so it could be also a lens issue. <br>

Anyway, what Charles say: look at the image, not the grain.</p>

Link to comment
Share on other sites

<p>To clean the ground glass and fresnel<br>

1. remove the view hood (4) by pulling out on one side or the other<br>

2. remove the focus panel from the back by pressing down on the knurled section of arms (9) and sliding the focus frame (15) right until the hooked end of arm (9) is clear of the lock pin.<br>

3. remove the screws (5) and the clips (6)<br>

4. carefully remove the ground glass (7) and fresnel (8) from the focus panel.<br>

5. wash both in warm water with dish detergent rubbing with your finger tips only while handling by the edges only. On the fresnel rub the grooved side with the groves only, never across them. The grooved side should have been facing the ground glass. Use finger pressure equivalent not to move the skin of an over ripe grape.<br>

6. rinse thoroughly under running water.<br>

7. rinse in a weak photoflo solution then stand on edge and allow to air dry.<br>

8. install the fresnel in the focus frame with the smooth side down, ribbed side up.<br>

9. install the ground glass on top of the fresnel with the ground side down.<br>

10. install clips (6) and screws (5).<br>

11. adjust clips (6) so that focus hood (4) snaps in easily then snug screws (5). Do not over tighten.<br>

12. reattach focus panel to the camera back by sitting it in the film holder area flush then pushing left until the arm (9) snap under the lock pins. </p><div>00dzKH-563555584.jpg.eed4301b4e430538774eab21b9a6085f.jpg</div>

Link to comment
Share on other sites

2.7 -3.5.., I'm afraid to go higher to screw up the actual dof, when i want the swirlynes of 2.7

so I cleaned the glass, looks gery good, but outside its still very hard to get the focus right when the subject is far away.

 

normally i focus on eyelashes, so i have the contrast, but mybe asking the model to put something contrasty on her face

would help? but whaat?

Link to comment
Share on other sites

<p>For those hard-to-focus conditions (mostly under dim light), I like to use cheap bike type LED rear pilot light... the ones used under the saddle. Just place it exactly at the focus plane.<br>

Another option (just thinking aloud) could be a laser pointer mounted on a small ball head&clamp, pointing to the subject. You can attach it to a tripod leg or whatever.</p>

Link to comment
Share on other sites

But your link goes to what you don't want to use for correct focusing since it is pre focused instead of being able to be

adjusted so you focus on the actual grain surface of the gg where the film will actually be placed. This loupe will always

be out of focus by, at least, the thickness of the ground glass and even more if a top mounted Fresnel is used!

Always use a loupe that can be adjusted. In addition, this is an open tube design which will allow light to enter from the

sides creating flare on the gg and making focusing more difficult. A focusing loupe for a gg should have an opaque skirt.

Not a clear or translucent one.

Link to comment
Share on other sites

<blockquote>

 

 

<p>2.7 -3.5.., I'm afraid to go higher to screw up the actual dof, when i want the swirlynes of 2.7 so I cleaned the glass, looks gery good, but outside its still very hard to get the focus right when the subject is far away.<br>

normally i focus on eyelashes, so i have the contrast, but mybe asking the model to put something contrasty on her face would help? but whaat?</p>

 

 

</blockquote>

 

what i do is i stop down to about f4, and then open up again when i take the photograph. a bright light helps illuminate if you can't see the subject, and just turn the light off when

you open up and expose the film

Link to comment
Share on other sites

If you have a lens that shifts focus with taking aperture then by all means, focus at taking aperture. One example of a lens

that behaves this way is the Imagon.

But if your lens does not shift focus as you change aperture then you will always focus most accurately wide open.

Link to comment
Share on other sites

<p>not sure .. it never posed a problem .., neither has stopping down a tiny bit <br>

when focusing tessars either .. but i am sure there are issues with some lenses ...<br>

i have heard schneider symmars (convertibles) have focus shift, but they aren't old<br>

brass and fast ... </p>

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...