Ikoflex infinity focus, and focussing screens

[mskb]

Dear All, 

I have a feeling that my Ikoflex IIA is not focusing to infinity. Because the throw of the focus wheel from 48 -> Infinity is small, I want to be sure that this is a genuine concern. I had a few questions. I would greatly appreciate your insights!

1. Is there a good way to make sure of the issue? There is no movement of the focus wheel past infinity, and focusing on clouds feels like I could use "jussst a bit more" movement in the focus wheel. Does trying to focus on stars work? Its been a while since we had clear nights. Any non-star options?  

2. Is it possible to read off the distance at which the camera is focused from the Depth of Field scale, printed around the focusing wheel? For example, after fully rotating the focus wheel for focus at infinity, my infinity point in the DOF scale does not ever hit the 'center' mark of the DOF scale, it stops a bit before it, but then I am not sure if the center mark refers to the distance at which we are focused. 

3. To make sure the ground glass and focusing screens of the IIA are assembled properly, could you let me know (a) the correct order of the ground glass and the focusing screen, and (b) what sides of the ground glass and focusing screen should face the mirror? I hope I am using the terminology correctly. 🙂 

Thank you very much!

[arthur_mcculloch2]

Hi, mskb. I have not used an Ikoflex, but have used other TLR's (Yashicamat, Airesflex, and a Rolleicord), so my comments are based on their use:

1. The only way I could reliably, and cheaply, check focus was to use a ground glass on the open back. Others have posted the technique. It's a bit fiddly, but basically you use a ground glass where the film would go, focus at full aperture to infinity, set to 'B' (to keep the shutter open), and use a magnifying loupe to check the focus on something at infinity. You can do the same at close and medium focus, though many say that if you get infinity right, the rest falls into place. I'm pretty sure others have posted more explicit details on how to do it on this site.  A google will bring up further information on how to do it.  At close distances, if everything is ok, the distance for crisp focus (measured independently - I use a long plank with measured distance markings) should correspond with the distance indicated on the focus dial, and should match the focus in the WLF. A more complex, expensive, and time consuming way to check focus accuracy is to use film and focus on a line of objects at known distances (in the past, I've used a plank with a line of nails at 3" separations, focused on a particular nail). It can indicate if you're front or rear focusing.

2. Yes, as I understand it. The distance you are focused at should 'line up' with the centre mark in the depth of field scale.

3. As I understand it, the ground glass side should face the mirror.

I hope that helps. If I've mislead you, others will no doubt correct me. Good luck with your Ikoflex. They have a reputation for build quality and very good optics. And of course, there's the nostalgic joy of using a TLR and seeing the world back the front. Regards, Arthur.

Edited April 2 by arthur_mcculloch2
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