Mamiya C220 focusing screen extremely dark & low contrast

[sixby45]

Good morning everyone,
I was reading through the WLF post in the forum, and realized I'd love some advice on how to best focus a TLR with dark ground glass, without a split image finder. For some reason my Mamiya C220 TLR has an oddly dark finder, and the picture which should snap into focus, does not quite do this. The center is a circle, but it does not exhibit the traditional Fresnel diamond microprism "wavy-ness" nor does it appear any lighter than the surrounding area.

This leaves me to use the magnifier more often than not, however even with this, as an eyeglass wearer varying the height of the TLR makes a huge difference in what I am able to see correctly. Ive seen in videos that people really get right up on the WLF with their eye, however when I do this, almost nothing seems in focus, so optimal viewing distance seems like at chest or waist level.

I know that the C220 doesnt do removable focus screens with ease like the C330 - am I stuck with this viewfinder or is their something I can clean to make it brighter?

I've recently swapped the lovely 65mm 3.5 lens to an 80 2.8 - and was expecting a big difference - however it looks almost identical.

Thanks for any tips for TLR focusing & C220 / C330 focusing screen help.

 

[abruzzi]

When I got my ETRSi, it had a standard focusing screen, without any focusing aids, and unfortunately, screens by themselves are uncommon and expensive. I've always liked the split prism, preferably at 45 degrees, but on my Pentax 67 I had got used to the microprisms. So I had to get used to no focusing aids on the ETRSi. What I have found, so far is the following:

- If you have a pop up focusing loupe--always use it. Without it focusing by eye is pretty hard.

- When actually focusing, what I have felt works best for me is to to back-focus, then front-focus, back and forth several times, making my movements smaller each time, and gradually zeroing in on where focus should be.

It's not fast, but it works for slow shots. A small aperture can help if you miss focus a bit.

 

[Marcelo Paniagua]

Hello there


I mostly focus at chest level. I'm also a glasses wearer but normally take them when focusing. My eyesight isn't so bad I guess, because I get better result without glasses.

Have you thought on a prism hood? I have one and use it now and again. It helps a little. If you do, try to avoid the porrofinder, which is darker.

I've hard the Maxwell screen can light up things a bit but haven't tried them so far. You may get info on :

http://www.rolleirepairs.com/maxscreen.htm

Bes of lucks.

Marcelo

 

[Alan Gales]

I bought a C220 and found the screen fine for outside but a bit dark inside. These cameras are cheap so I just replaced the whole camera with a later C220f. It has a brighter screen similar to the C330s. It's still a little dark inside so I do as Marcelo does and focus at chest level when indoors. Sometimes I also do as abruzzi and use the magnifier.

The later C220f is of course more money and has more plastic parts. It has a knob instead of the fold out crank for film advance. The screen is a bit brighter though and worth it to me. It's still not a bright as my old RZ was or especially the Hasselblad with the Beattie screen I had.

Of course all of our eyes are different. Mine are slowly getting worse with age. For you it may be worth the money to buy a Maxwell screen.

 

[David Brown]

I've owned a C220 for decades. I also use an RB67. I always use the magnifier for focusing, and then the open screen for framing.

One trick I've used when you have the camera on a tripod, and are able to get to the focus point, is to set a light source such as flashlight at the place you want to focus on, and focus on the light. Remove the light and take your shot. Not always possible, but it works in darker interiors.

It is also possible that your focusing screen could stand a cleaning.

 

[MattKing]

It is also possible that your focusing screen could stand a cleaning.

All parts of the viewing system are best if they are clean and undamaged.
And of course, our eyes change too.

 

[jimjm]

If you can, check the reflex mirror under the focusing screen as well. If it's dirty, pitted or flaking it'll have a big impact on your viewing image.

I have a Rollieflex Automat that had this problem. Found a replacement on eBay easily, and it made a huge difference.

 

[Marcelo Paniagua]

If you can, check the reflex mirror under the focusing screen as well. If it's dirty, pitted or flaking it'll have a big impact on your viewing image.

I have a Rollieflex Automat that had this problem. Found a replacement on eBay easily, and it made a huge difference.

+1 Had this issue on a Rolleiflex 3e2 and with a Yashica. Replacing them makes a difference.

Regards

Marcelo

 

[paul ron]

clean the mirror and replace the screen with a split screen.

 

[RalphLambrecht]

Good morning everyone,
I was reading through the WLF post in the forum, and realized I'd love some advice on how to best focus a TLR with dark ground glass, without a split image finder. For some reason my Mamiya C220 TLR has an oddly dark finder, and the picture which should snap into focus, does not quite do this. The center is a circle, but it does not exhibit the traditional Fresnel diamond microprism "wavy-ness" nor does it appear any lighter than the surrounding area.

This leaves me to use the magnifier more often than not, however even with this, as an eyeglass wearer varying the height of the TLR makes a huge difference in what I am able to see correctly. Ive seen in videos that people really get right up on the WLF with their eye, however when I do this, almost nothing seems in focus, so optimal viewing distance seems like at chest or waist level.

I know that the C220 doesnt do removable focus screens with ease like the C330 - am I stuck with this viewfinder or is their something I can clean to make it brighter?

I've recently swapped the lovely 65mm 3.5 lens to an 80 2.8 - and was expecting a big difference - however it looks almost identical.

Thanks for any tips for TLR focusing & C220 / C330 focusing screen help.

I had a similar issue with my Hasselblad501c and fixed it by getting an inexpensive Chinese split screen. It made it even darker but the split screen makes up for it because ,I found nothing easier to focus with.

 

[grahamp]

If your eyesight will not let you focus the boundary of the central focus spot sharply, you will not get a sharp picture. This is true of any camera that uses a focus screen.

I find I am fine with my regular glasses and the flip-up magnifier, but you might need a different prescription. For view cameras I use flip-up magnifiers on my regular glasses. I need the astigmatism correction, and the magnification is enough for general work.

 

[flavio81]

Clean the mirror, the ground glass, the fresnel and try again.

 

[flavio81]

Ps: Also, i think split image aids suck. I can focus more precise with plain matte ground glasses, as long as they are clear and bright.

 

[sixby45]

Thank you all who responded for your insight - definitely have some things to try now! I'll let everyone know how it goes

 

[Luckless]

One point to keep in mind when you go to clean the mirror is that almost all mirrors used in an optical system like a camera are front silvered, not rear silvered like typical household mirrors. Be very careful and gentle in how you clean them, and take the time to google some tips and methods on handling such mirrors.

If you're feeling creative, adventurous, and have a decent shop setup, then it is also totally possible to re-silver (deposit aluminum) on a small mirror at home, but typically replacing one is the far more sensible option. But not nearly as fun or geeky if you ask me.


Not sure how the focusing screen on the 220 is, but on my 330f it is a dual layer setup, and mine had gathered a fair bit of crud between the pieces.

 

[ic-racer]

Without a fresnel it will be dim. Low contrast points to hazy film on the mirror and/or focusing lens.

 

[flavio81]

One point to keep in mind when you go to clean the mirror is that almost all mirrors used in an optical system like a camera are front silvered, not rear silvered like typical household mirrors. Be very careful and gentle in how you clean them, and take the time to google some tips and methods on handling such mirrors.

This. I use a blower to try to take out all the dirt. Then what I do is I take some soft toilet paper/tissue, which I spray generously with glass cleaner, and roll it as to create a very soft "wet brush". I then slide this 'brush' across the mirror without applying any force, so basically the wet tissue is 'gliding' across the mirror. I only do one pass, overdoing it can scratch it.

Of course this procedure is to be performed after removing the top of the Mamiya C220, to get full access to the mirror. This also means that any washer should be placed exactly where it was, on reassembly.

If you're feeling creative, adventurous, and have a decent shop setup, then it is also totally possible to re-silver (deposit aluminum) on a small mirror at home, but typically replacing one is the far more sensible option. But not nearly as fun or geeky if you ask me.

Yes, you can deposit silver, but there are two problems:

1. camera mirrors are not only silvered, they also get anti-reflection coatings

2. the different glass thickness mean that you will have to re-adjust the mirror angle, which may or may not be easy.

An alternative is to get those Polaroid instant cameras that had one big mirror inside (i.e. OneStep); and use that mirror.

Not sure how the focusing screen on the 220 is, but on my 330f it is a dual layer setup, and mine had gathered a fair bit of crud between the pieces.

C220 is dual layer: fresnel (plastic) plus ground glass. And yes, it can get crud between the pieces!

 

[John Wiegerink]

One way to see if your mirror is the culprit is to hold the camera facing you and put your eye up to the viewing lens while aiming the hood side (hood open of course) toward a bright light source. You'll get a good idea very quickly as to how clean your mirror is. A couple of specs of dust are nothing, but an oily type of gas film is something that needs to be taken care of. Fungus might also be a problem and might not be removable. Good luck! JohnW

 

[ransel]

Of all the TLR's I have owned (Rollei, Autocord, Yashica 124G & D) the Mamiya C's have been the easiest to focus, so I find this perplexing. But, since even the brightest TLR focusing screen can be difficult on aging eyes, I have mounted a Chimney finder on my C220 and now I never miss a shot due to focus. It adds a little bulk to the camera (about 3" in height) but it's worth it. It has a rubber eye-cup to keep out any extraneous light and a flip-up magnifier.

 

[sixby45]

Thanks Ransel - this is indeed what I've worked on - the magnifier does help quite a bit!