Sinar Calculator - Basic Help Please

[SteveH]

All, After exhausting the search feature, I am asking anew. I currently have a Sinar F2, and am trying to figure out the focusing/DOF calculators. This is what I know:

1)I understand the DOF calculator on the right side of the camera.

2)I understand the knob on the left of the camera with regard to tilts, and the usage of the dashed top and bottom line on the camera's GG

Now for what I don't understand/not sure of:

Can the left side knob also be used for swings, the same way that it is used for tilts ? What use do the pointers (which are mounted on the sliding portion of the standard) have when they refer to a various number (which is on the rail clamp portion of the standard). Lastly, any other feature which I have neglected to mention ?

Thanks in advance,

 

[NikoSperi]

I'll drop a line here just so I'm subscribed to this thread. I'm in the same boat with the F2. Regarding the tilt calculator, I don't see why it would not work the same way for swings... it's up to your selection of what to use as a desired plane of focus, no? If your plane is largely horizontal, as would be in a landscape, say, then the tilt is used to set the angle required as indicated by the calculator. But if the plane is vertical, as in a receding building, the calculator still reads off the closest and further points. Set that angle with the swing.

Ok, ready to be brutally corrected now... :rolleyes:

 

[SteveH]

Ok....From the LF.info board...
Basically the same procedure/items are used for both swings and tilts. The pointers on the side WERE used for the calculation on the F/F+, but not give you a ref. point for how far you have focused - nothing more.
Sinar recomends to calculate your tilts first, then your swings.

Hope that's right...

 

[NikoSperi]

Ah... those pointers. Yeah, my understanding is they are useful as a point of ref for precise bellows measurement and image mag, etc... I was thinking about the angular tick marks on the swing and shift scales of each standard.

 

[SteveH]

Yupper...So I guess that basically figures everything out. You know how the DOF works correct ?

 

[NikoSperi]

You're refering to the wheel on the right hand side, with the 4x5 and 6x9 formats? I focus on my far point, set it to zero, focus into my near point, read the f/stop, and move out two stops... For example, it says I need f/45 to achieve my desired DOF, I use that as my working aperture, but rack focus back until it reads f/22... Correct?

Any good source for a manual or website of sorts for the F2?

 

[SteveH]

Actually...I do have one more question.
After you have the tilt figured out...Do you then focus back to the zero reading, or do you leave the focus where it is at, zero the dial, then figure out your swing ?
Then once the swing is calculated, do you leave the focus setting where its at, or refocus everything ? Sorry, I know it sounds confusing...

 

[NikoSperi]

Read that a couple times, and then I got it!

I refocus after tilt. In other words, say I'm only using tilt. With the standards square, I'll see I need something smaller than f/64 to get the DOF I want in the plane of focus I want. So I use the tilt calculator to shift my plane of focus. Once tilt is set (say 12 degrees), I redo my DOF test, which should now show that I only need, say f/32. From there, I rack the focus in until the DOF wheel shows f/16 and I'm done.

If I then also need swing... my little brain is going to pop. I would repeat the process, except looking to move the plane of focus along the swing (vertical) axis. I guess I could do another DOF test along the swing axis, and shoot at the greater resulting aperture.

In short, the movement calculator tells me where the extremes of my focus range are, and whether I need movements to "fit" everything in. Focus, however, is still the final step using the DOF caculator?

Confused yet? I am. :rolleyes:

 

[SteveH]

Ya, that should be correct. However, I don't think that it is necessary to do the DOF first, as you can go right into the tilt and swing. So...to get a running tally:

1 - Rough focus
2 - Focus on the foreground, and zero the left dial
3 - Focus on the background, read the left dial, and tilt accordingly
4 - Focus on the left side of the glass, and zero the left dial
5 - Focus on the right side of the glass, read the left dial, and swing accordingly
6 - Do your DOF calculation as you would normally, except now your perspective/sharpness should
be all over the image.

Maybe...Maybe not ?

 

[Shmoo]

I copied this from the Sinarbron website (when they used to have this online...not sure they still do):
===============
Tilts:
1. Focus on the bottom horizontal dotted line on the groundglass.
2. Zero the angle calculator on the left side of the rear standard by turning it until the 0 lines up with the white mark.
3. Focus on the top horizontal dotted line on the groundglass using the fine focus on the rear standard. The angle calculator will automatically indicate the required degree of tilt.
4. Set the front standard tilt to the angle indicated on the dial.
5. Adjust focus if needed.

Swings:
1. Focus on the right-hand vertical dotted line on the groundglass.
2. Zero the angle calculator on the left side of the rear standard by turning it until the 0 lines up with the white mark.
3. Focus on theleft-hand vertical dotted line on the groundglass, using the fine focus on the rear standard. The angle calculator will automatically indicate the required degree of swing.
4. Set the front standard swing in the angle indicated on the dial.
5. Adjust focus if needed.

Depth of Field:
1. After setting any swings and tilts, focus on the farthest point you want to keep in focus.
2. Set the depth of field scale to the zero point by lining up the arrow on the scale with the white dot on the camera. Turn the scale only, not the focusing knob.
3. Focus on the nearest point you want to keep in focus, using only the fine focusing drive on the rear standard.
4. Set your aperture to the f/stop indicated on the depth of field scale.
5. Turn the rear fine focus knob back until the depth of scale reads half your working f/stop (for example, from f/22 you would turn babck to f/11). You are now focused at the optimum point for that depth of field.

==================

I keep this little blurb in a little cheat sheet with my equipment...

 

[SteveH]

That's perfect. Thanks a bunch.