bessa 66, heliar, unsharp pictures

[wupdigoj]

The cuts in the tape are what give you something to focus on; sanded film doesn't.[/quote]

I am sorry, I didn't explain myself (i could do much better in spanish ). I didn't sand the film, but made lines in it with a needle or something like that. I have used also a pen, but the lines are not narrow enough.

I have something new. Checking the camera again, I have noticed that the frontal lens, the one you use to focus, turns a little when the shutter is released: the helical is very free, and the compur rapid is very energic. I think this can be, at least partially, the cause of the unsharpness, as in the SLR I used the focal plane shutter, not the compur. I will grease the helical to make some resistance, and I think I will give this camera a last chance. The attached pictures are taken with the same lens, one in the bessa, and the other one in a SLR 35 mm camera.

 

[chippy]

It makes it arkward Javier to give sound advice or asistance without further details...great that you now have some pics!..the bessa no doubt is the terrible image! and it is terrible!! but what other details are missing. was it taken using a tripod? cable release ect and so on... it appears a cavilear shot in as much as its out of level...

if you are trying to get to the bottom of the problem all these things for testing purposes must be taken into account...this knew information on the front lens helical is impotant as well! did it not appear too loose with hand focusing? one would think so, if merely the shutter action can move it! one thing is certain that there is and will be a slight differance with the front cell focusing heliar and the unit focusing heliar but the results should be way beyond what you image represents

 

[ZeissFan]

Javier, I agree with you that maybe it's time to give up on the camera.

One camera to consider is the Zeiss Ikon Ikonta. These are available in 6x4.5, 6x6 and 6x9 and come with either a Novar or a Zeiss Tessar with the Tessar being the "premium" lens.

The 521/16 with the Tessar seems to be readily available and not too expensive (often about $50-$65). The Novar model should be about $10-$15 less.

The 6x4.5 models seem to be a bit more expensive than the 6x6 models.

If you don't mind respooling, the Kodak/Nagel Duo 620 is a very fine 6x4.5 model with either a Tessar or Kodak Anastigmat. I can't recall if these also came with a Xenar. These seem to sell for about $30 or so.

There also is a Kodak/Nagel Vollenda 6x6 model that comes up now and then and also is a very good camera.

 

[FallisPhoto]

I am sorry, I didn't explain myself (i could do much better in spanish ). I didn't sand the film, but made lines in it with a needle or something like that. I have used also a pen, but the lines are not narrow enough.

I have something new. Checking the camera again, I have noticed that the frontal lens, the one you use to focus, turns a little when the shutter is released: the helical is very free, and the compur rapid is very energic. I think this can be, at least partially, the cause of the unsharpness, as in the SLR I used the focal plane shutter, not the compur. I will grease the helical to make some resistance, and I think I will give this camera a last chance. The attached pictures are taken with the same lens, one in the bessa, and the other one in a SLR 35 mm camera.

If it is that loose, I'm wondering if the front element has been replaced at some point. The lens elements were individually matched for each camera, you know; it wasn't "mix and match" interchangable.

 

[fidget]

Something that I would be wanting to determine is, given a scene with objects between say 3m and infinity camera focussed at say 10m , is anything in focus?
It would be good to know if this was a "wrong" focus problem or other lens related issue.
(I read once that someone here had re-assembled a lens but had put one element in the wrong way round. Something like this at play?).

 

[FallisPhoto]

I am sorry, I didn't explain myself (i could do much better in spanish ). I didn't sand the film, but made lines in it with a needle or something like that. I have used also a pen, but the lines are not narrow enough.

I have something new. Checking the camera again, I have noticed that the frontal lens, the one you use to focus, turns a little when the shutter is released: the helical is very free, and the compur rapid is very energic. I think this can be, at least partially, the cause of the unsharpness, as in the SLR I used the focal plane shutter, not the compur. I will grease the helical to make some resistance, and I think I will give this camera a last chance. The attached pictures are taken with the same lens, one in the bessa, and the other one in a SLR 35 mm camera.

Okay, I still don't see what holes in backing paper have to do with anything though. If you want to use etched film instead of glass, that's your business, but you are supposed to open the back of the camera and use NO backing paper.

 

[wupdigoj]

Okay, I still don't see what holes in backing paper have to do with anything though. If you want to use etched film instead of glass, that's your business, but you are supposed to open the back of the camera and use NO backing paper.

Thank you for your answers. The interest of all of you in this matter is encouraging me to try to make this camera take sharp pictures...

I DO use backing paper and I DO close the back of the camera.
I will try to explain the complete procedure:

- First, you take a blank film (not exposed, not developed, fixed)

- You draw some lines with a very fine pen in the side of the film facing the camera lens (not etch the film or sand it, just draw lines). You will use these lines as a reference to focus with the split-image prism of the SLR viewfinder.

- In the places where you have drawn the lines, you make a hole in the back paper, in the case of my camera just in the center, because the red window is in the center The size of the holes should be about the size of the red window of the camera (5 or 6 mm , perhaps)

- You roll the film and backing paper in the usual way, put in the camera and close it. With the lens in B and the red window open, you feed the film until your see the film spot with lines thru the red window and thru the hole in the backing paper. If you don't make the hole in the paper, you will not be able to see the film and the lines. If you don't use the back paper, the pressure and location conditions of the film will not be the same as in using the camera with real film.

- Put face to face the camera lens and a SLR using a long and fast lens. You put a strong and diffuse light in the back of the camera, and adjust the focus until you see a sharp image of the lines drawn on the film in the SLR's viewfinder. Obviously both cameras should be focused at infinity. In this situation the film plane will be exactly in the focus plane of the lens.

This procedure is (I think) basically the same as using a real collimator, with the only difference that you use transmitted light instead of reflected light. The hole in the paper could also disturb the position of the underlying film, but I suppose this effect is very small.

In some cameras, I have found a very small difference between the two methods (mine and using a ground glass), but in others, the difference can be as big as 0,6 mm. This difference in the location of the focus plane is enough to kill the sharpness of a good lens when using large apertures and/or near subjects. I think that many lenses reported as soft wide open are really much sharper, but are just bad collimated.

I don't really know if this explanation (or the procedure for that matter) make sense or no, but it seems to work well for me so far.

Sorry for my English. Regards

Javier

 

[Solinar]

Javier, that's pretty close to the method that I use.

Here is - Rick Oleson's web page - showing the basic set up.

Things that I do differently than what is described are:

On the camera used for viewing the projected image choose a long focal length lens 135 mm or 180 mm, preferably with a f/2.8 aperture.

Cut a rigid plastic plate from a a clear plastic CD jewel case used to store your least favorite compact disc. Cut the rigid plastic plate so that it will rest along the film rails.

With a permanent marker draw a cross on the side that will face the camera lens. In addition to the cross I scratch a big X with a sewing needle. Both the cross and the X are your target.

Place the plastic target on the film rail - securing it with rubber bands. You may need to add folded paper between the rubber bands and plastic target which act as pressure points to hold it firmly against the film rail.

Leave the back of the camera open - so you can check the focus adjustment of Heliar at infinity using much more light than you are currently.

 

[FallisPhoto]

Thank you for your answers. The interest of all of you in this matter is encouraging me to try to make this camera take sharp pictures...

I DO use backing paper and I DO close the back of the camera.
I will try to explain the complete procedure:

- First, you take a blank film (not exposed, not developed, fixed)

- You draw some lines with a very fine pen in the side of the film facing the camera lens (not etch the film or sand it, just draw lines). You will use these lines as a reference to focus with the split-image prism of the SLR viewfinder.

- In the places where you have drawn the lines, you make a hole in the back paper, in the case of my camera just in the center, because the red window is in the center The size of the holes should be about the size of the red window of the camera (5 or 6 mm , perhaps)

- You roll the film and backing paper in the usual way, put in the camera and close it. With the lens in B and the red window open, you feed the film until your see the film spot with lines thru the red window and thru the hole in the backing paper. If you don't make the hole in the paper, you will not be able to see the film and the lines. If you don't use the back paper, the pressure and location conditions of the film will not be the same as in using the camera with real film.

- Put face to face the camera lens and a SLR using a long and fast lens. You put a strong and diffuse light in the back of the camera, and adjust the focus until you see a sharp image of the lines drawn on the film in the SLR's viewfinder. Obviously both cameras should be focused at infinity. In this situation the film plane will be exactly in the focus plane of the lens.

This procedure is (I think) basically the same as using a real collimator, with the only difference that you use transmitted light instead of reflected light. The hole in the paper could also disturb the position of the underlying film, but I suppose this effect is very small.

In some cameras, I have found a very small difference between the two methods (mine and using a ground glass), but in others, the difference can be as big as 0,6 mm. This difference in the location of the focus plane is enough to kill the sharpness of a good lens when using large apertures and/or near subjects. I think that many lenses reported as soft wide open are really much sharper, but are just bad collimated.

I don't really know if this explanation (or the procedure for that matter) make sense or no, but it seems to work well for me so far.

Sorry for my English. Regards

Javier

Yes, I figured that. The problem is that the light coming into the back of the camera, through the red window, is going to be too dim. SLRs don't focus well in dim light. That's one of the reasons we use rangefinders in the first place.

Look, have you ever used an enlarger? If so, you know that the first thing you do, when focusing an image, is open the lens as far as it will go. If you don't, you can't focus it at all accurately. You really do need all the light you can get. Seems to me that trying to get light into the camera, just through that red window, you'd just about need a laser.

The next thing to think about is that, if you are seeing that much difference between film with and without paper backing, you probably need to retension the springs on your pressure plates. Sounds to me like some of your pressure plates are not doing their job of pushing the film tight against the film rails.

 

[chippy]

Javier, that's pretty close to the method that I use.

Here is - Rick Oleson's web page - showing the basic set up.

correct me if i am wrong but there are two different methods being discribed in this thread as though they are one and the same, but they are not. there in lies the confussion.

Javiers method, and i assume also Solinars (Andrew in Texas), going by his discription as i understand it (correct me if i am wrong Andrew), is the complete opposite to what i beleive FallisPhoto is thinking/saying and what Rick Oleson's method shows. however the set up is almost identical to look at, but is different. however, they both work.

the difference is, with Rick Oleson's method the target (e.g. plastic/tape or whatever, with cross marked on it) is placed on a correctly collimated lens/camera, not the camera to be adjusted/collimated and set at infinity. this method is basically the same as taking the camera outside and focusing on a distant object to set infinity correctly on the camera/lens that needs adjusting/collimating. The camera with the target attatched to it, is simply used in place of taking the camera outside to focus on a distant object.

in Rick Oleson's example he is adjusting/collimating his 35mm silver OM1 SLR camera, which is why he looks through its viewfinder, in our case using this method we would have to use ground glass on the film plane to view the scene outside, OR in Rick Oleson discription to view the correctly collimated camera (not to be fixed/adjusted/collimated camera) with the target attatched to it.

In contrast, using Javier and Solinar's method the target is placed on the camera with the lens that needs adjusting/collimating and the second camera (mostly people use and SLR) is the correctly collimated camera which is looked through to view the target/cross, and the front element is moved on the camera that need adjusting until the cross comes into focus through the SLR viewfinder,

i havnt used the cut the hole in the backing paper and try to see the marks on the film method while shinning a light through the red window as Javier has mentioned (try saying that quickly hehe). a strong lght would be needed but if he says he can see it sharply then it must work at least for him.

I am more curious about the front element that Javier mentions being loose and shifting when the shutter fires!!! thats just hoky haha

 

[Solinar]

Actually with Rick Oleson's method, the target (e.g. plastic/tape or whatever, with cross marked on it) is placed at the rear of the camera that has the lens which you are checking to see if it is properly adjusted at infinity.

The viewing camera has a lens mounted that is known to have the correct collimation at infinity.

With both lenses set to infinity, what you'll see looking through the viewing camera should look like this.

 

[chippy]

Actually with Rick Oleson's method, the target (e.g. plastic/tape or whatever, with cross marked on it) is placed at the rear of the camera that has the lens which you are checking to see if it is properly adjusted at infinity.

The viewing camera has a lens mounted that is known to have the correct collimation at infinity.

With both lenses set to infinity, what you'll see looking through the viewing camera should look like this.

maybe we are looking at different web pages? i dont see that picture there.

check this page http://rick_oleson.tripod.com/index-123.html

 

[dnk512]

How do you focus when you use the lens on a 35mm body? Do you still rotate the front element? Or do you move the lens as one piece back and forth?

Also, the pictures you test as unsharp, are they at infinity? or near objects?

There was another thread (here -- can not find it now) that remarked on how a front focus lens needs to be spaced (with black pieces of paper) on the mount till infinity AND 10 feet and 3 feet objects get sharp by rotating the front element only.

I found the above very true with my folders.

 

[chippy]

Actually with Rick Oleson's method, the target (e.g. plastic/tape or whatever, with cross marked on it) is placed at the rear of the camera that has the lens which you are checking to see if it is properly adjusted at infinity.

The viewing camera has a lens mounted that is known to have the correct collimation at infinity.

With both lenses set to infinity, what you'll see looking through the viewing camera should look like this.

you must be looking at something different to me? His page with these pictures show the target/plastic/tape ect in fixed to the camera with the known good lens and is set to infinity.

 

[Solinar]

Both Rick Oleson and I describing what used to be called the back-sighting method .

In the first drawing he is showing the set up for the target camera to include locking cable release - which I forgot to mention. The target camera, which has the lens in need of collimation, will then be mounted in front of a lamp - hopefully with the light angled a bit to avoid flare.

Your second photo shows the target camera to the left and viewing camera to the right. Notice that the light shines into the back of the target camera.

In the third photo/drawing the target camera has a backlight - the viewing camera is to the right. It would be better if he showed the viewing camera with a 135/2.8 or 180/2.8 mounted to it - which makes a difference.

My photo shows what you should see when looking into the viewing camera. I say it is better use a long focal length lens on the viewing camera, preferably fast, because it magnifies whatever image that passes from through the lens of the target camera.

 

[Solinar]

Back-sighting a Bessa using a Praktica with a 135/2.8 to view the target on the Bessa's film plane.

 

[chippy]

Both Rick Oleson and I describing what used to be called the back-sighting method .

In the first drawing he is showing the set up for the target camera to include locking cable release - which I forgot to mention. The target camera, which has the lens in need of collimation, will then be mounted in front of a lamp - hopefully with the light angled a bit to avoid flare.

Your second photo shows the target camera to the left and viewing camera to the right. Notice that the light shines into the back of the target camera.

In the third photo/drawing the target camera has a backlight - the viewing camera is to the right. It would be better if he showed the viewing camera with a 135/2.8 or 180/2.8 mounted to it - which makes a difference.

My photo shows what you should see when looking into the viewing camera. I say it is better use a long focal length lens on the viewing camera, preferably fast, because it magnifies whatever image that passes from through the lens of the target camera.

Perfect picture and example to show Andrew, nice to see a bessa getting a tune up, looks great thanks.

however please read Rick Olesons page again and you will see his method and yours are different.

which as i said in my earlier post, is why there seems to be some confusion. they look the same at a glance but they are different

The difference is, the camera with the lens being adjusted, in Ricks example, is not the camera with the plastic/cross marked on it. it clearly says (you can read it on the first picture) that the camera with known good lens has the plastic with the cross marked on it...and the camera oposite with no plastic or cross marked on it, is the lens to be evaluated (or adjusted/collimated).

yours and Javiers method is the opposite to Rick Oleson and what i think FallisPhoto was saying, in as much as the camera with the plastic/marked cross, is the camera lens being evaluated (adjusted/collimated), both methods work of course as i said and yours is possibly the better way if there is a difference in outcome. but what i am seeing is that they are different methods or at least different set ups to acheive the same thing

 

[Solinar]

Interesting - I don't see how else would you test the collimation on a non-SLR lens unless you use the ground glass and loupe method.

 

[chippy]

Interesting - I don't see how else would you test the collimation on a non-SLR lens unless you use the ground glass and loupe method.

basically in Ricks method the lens takes the place of the loup, the cross takes the place of the distant object and the plastic takes the place of the ground glass...the difference is you are looking at the ground glass from the opposite side in manner of speaking.....

i should add that with testing a folder camera, as i said in my earlier post, you would need to use ground glass and loup, to look through the folder lens. but just the same his method shown is different (the opposite to yours). the avantage with his method over the usual ground glass method is its more compact, precise and no need to go outside stumbling around with camera, tripod and levels ect. there is no advantage over your method at all!

 

[wupdigoj]

Thank you again for all your useful comments. Regarding the red window, my camera does not have the red filter, just a hole (it lack also all the letherette of the back). No light leak. Nevertheless I have found my method usable, even with a red windows provided the light source is good (a 100 W table lamp is ok) and a fast SLR lens (2.8 is OK). I think it is the same method as the Rick Oleson. The difference I found it is not between with or without back paper, but between film and a rigid ground glass.

In this lens you can not change the position of the frontal lens to collimate it, because the ring that support it is retained by 3 screws, not in the lateral of the lens, but in the frontal part, with holes in the lens mount. So I just added shims to get infinity focus ( a lot of them i must say).

It seems to me that the problem of the camera is not related with bad collimation: there is nothing in focus in unsharp pictures. The pictures I posted are taken with the same lens in the same position (I refer to the relative position of the frontal element). Both in a tripod, cable release. The films are Tmax in rodinal and foma 200 in ultrafin plus. I know, very different, but this can not account for the sharpness difference.

All the photos I took with the SLR are acceptable, even using the frontal element to focus, so it is not the lens, the lens is sharp. I wonder now why I didn't use the compur in some shots, instead of the focal plane shutter, to see its influence. I am now a little tired of tests to repeat it!.

When I bought the camera the focus ring was very stiff, and the shutter completely dead. I cleaned all the grease, and didn't put any in the helical, so it was really very free, but I didn't think this could be of any influence. The compur rapid in really very strong, enough as I said to move the ring sometimes.

I have put another roll in the camera, with the frontal lens play corrected. I have also tried to improve my handholding technique. Next weekend I will develop and post some results.

Thank you again for your time and interest. This discussion has been very useful for me!!.

Javier