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Focusing Screen Dilema...

v-system

New Member
I own a 500c/m and it came with a standard focusing screen. The screen is anything but "clean" and has a globular-shaped discolored area around the center of the image area that leads me to believe it was, somehow, left in the sun for a long, long time. Needless to say, I have great difficulty focusing in moderately subdued lighting.

I would really like to own an Acute Matte screen for this camera but before I spend $300 on the little, square, semi-transparent contraption I have some concerns you may be able to alleviate or have a good solution for.

I want grid lines. It is great using the spirit level for leveling the camera on a tripod but it would be so nice to have another means of aligning the horizon and verticals in a speedier (but still reliable) manner. The Acute Matte screen that comes with grid lines, unfortunately, also comes with a split-level rangefinder. According to the book "The Hasselblad Way" by H. Freytag (1978 ed., p 30) the split level rangefinder works with lenses through 150mm but not beyond. That is not the first time I've heard this. Others have complained of the split prism going dark under certain conditions -not just eye position- possibly a function of lens-speed/largest-apeture. Why this matters is that I use a 250mm Sonnar and would hate to not have the grid screen for use with this lens. Let me condense my questins here:

Does the modern split image rangefinder work with the 250mm Sonnar?

If the rangefinder image goes dark, can the regular screen area surrounding the split prism be used to achieve proper focus?

Should I instead try to find and purchase the older "checked" screen with microprism center?

Should I use a grid overlay on a blank Acute Matte screen?

Help -I think I'm going insane!
 
Hi Jakob. Others here with more experience than me will be able to answer your questions re various screens. I think it is true that a split image circle will not work very well with the longer focal length, such as your 250mm lens. Of course you can use the matte section of the screen to focus with the 250mm (instead of the split image). My favorite screen is the one that includes the large matte area with a central microprism and within that the smaller split image.....the best of all possible worlds. However, I don't know if this screen is available with gridlines.

If you live in southcentral Alaska.....we should get together sometime!

Gary Benson
Eagle River, Alaska
 
Gary, thanks for the suggestions. Eagle River, eh? I'd love to see Chugach State Park sometime... I live in Fairbanks. I haven't gotten down to Anchorage very often -mostly just to use your medical centers, unfortunately!

Almost forgot -I should add another caveat to my original question: would a dark split prism also adversely affect TTL metering with a metered prism finder? I'll bet it would. Not that I own one yet, but it would also be nice for distance shooting...
 
Screens with grid:

42250 old dim series, center clear magnifier circle.

42170 early Acute Matte with split

42217 Acute Matte "D" with split cirrently available

No grid but split with microprisms around the split is screen 42215.
This screen is supplied with all later 503CW bodies.

The split turns black not because of the focal length but because the light level reaching the split is too low.
This happens more often with longer lenses because the are less fast.
Take your 50 WA stop the lens down to 5.6 or 8 and see what happens.

The 42217 screen is the most wanted even though it is unfriendly priced at 220 euro incl. sales tax. :(
 
I am using the 42217 Acute Matte, wich is awesome to work with. Wish I could use it in my glasses too!
 
The #42250 Grid with Microprism center works well for me. I bought a huge pile of Hasselblad screens for $5 each at the local used photo stores. Hard to go wrong for these prices, IMO the #42250 is a very underrated screen. I just used mine for a low-light shoot (a rock concert) with the 40mm F4 and the HC-3, on a 500EL/M. It worked just great, and focusing this wide lens was not tough at all. Maybe it would work well for you. I've had Accute Matte screens of all kinds, I have sold most of them.

I like using the original Meter Prism, and in the original instructions, it states that Yes, screen choice can make a difference in metering accuracy. But several other variables are at play as well, possibly canceling each other out, or combining to make a bigger difference. Individual testing is required according to Hasselblad, and that is the reason for the +- switch on the Meter Prism. Mine are quite accurate, and were not expensive.

My 2 cents.
 
acute-matte 42217 or PM45 or both?

I have a hard time seeing well enough to focus accurately. I do have recently prescribed glasses. Reading the posts it seems that both the acute-matte 42217 and the PM45 with adjustable diopter could help. Does the PM45 use the focusing screen? I think probably it does and therefore the two would be best for focusing. If so, then I am on the lookout first for the screen to see if that in itself is sufficient and if not the PM45 as well. Please advise as I am new to the 500c/m. Thank you.
 
I have a hard time seeing well enough to focus accurately. I do have recently prescribed glasses. Reading the posts it seems that both the acute-matte 42217 and the PM45 with adjustable diopter could help. Does the PM45 use the focusing screen? I think probably it does and therefore the two would be best for focusing. If so, then I am on the lookout first for the screen to see if that in itself is sufficient and if not the PM45 as well. Please advise as I am new to the 500c/m. Thank you.

I'm not sure I understand you, but lets try: all finders use the screens in the camera. I think you might want to check one of the screens that are equipped with a split-image section. I personally find that the best solution. I wear contact lenses by the way.

Wilko
 
I use the acute matte D with split image.

On the CF150mm f/4 sometimes the split blacks out and can be very annoying, to solve this I just try to look at a different angle and suddenly the full split seems to work... so annoying YES, but with some patience you can make it work.

On the 250mm f/5.6 I would recommend trying it before you buy, it should be worst than the 150mm as the aperture is smaller but it might be that you can work your way around it...

If you are using the lens on a tripod and with lots of time to focus on your subject, you should be ok.
 
acute-matte D 42217

I just ordered a screen that is said to be mint from Igor's Camera. I am looking forward to making crisper focused pictures. Thanks for the input.
 
42250 Grid with Microprism???

Hallo...
I've a question about to focus screen 42250. I'm not sure that the 42250 focus screen have a microprism but i've read the reply post of Daniel Unkefer i'm confused.
Maybe there are two version of 4250????
Thanks
 
42250 Grid with Microprism???

Hallo...
I've a question about to focus screen 42250. I'm not sure that the 42250 focus screen have a microprism but i've read the reply post of Daniel Unkefer i'm confused.
Maybe there are two version of 4250????
Thanks
Zone,
the 42250 focus screen has indeed a grid and a central microprism area. I think it does no more appear in Hasselblad catalogues, so I recommend you to look for one at some well-furnished photo dealer. Since these screens are easy to damage (once a dealer tried selling to me a 42250 with the microprism area totally scratched) you need to examine them carefully!
I fear that microprisms, so as split-image rangefinders, may go dark at f/5.6 or smaller apertures, but I may be mistaking: I have no experience with other screens than the standard one on my 500 C/M and I speak referring to 35 mm. You can always focus on the surrounding matt screen, of course.
Good light and great pictures!
Ale
 
I installed the 42217 in my 503CW and it made all the difference over the standard screen. A nice thing s that you can install it (easy) so that the split micro prism will split either horizontal or vertical. As I only use my 50 CF F4 or my C ( late model ) 80 F2.8 I very seldom have a darken problem.
 
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