Maxwell Screen vs Acute Matte D

I've been using a plain Maxwell focusing screen on my 501C for the past number of years. I felt I was still having some difficulty with focusing, so I thought I'd try an Acute Matte split-prism screen. I ended up finding an Acute Matte D screen with the split prism and grid. It does have the two half circles to distinguish it from the Acute Mattes, though I really didn't care what version it was--I just wanted a split prism with a grid.

In the past I'd read that the Acute Mattes were slightly brighter than the Maxwells, but that at least with plain screens Maxwell screens "popped" more when in focus. However, to me it seems like the Acute Matte D is dimmer--I've attached photographs. Can anyone confirm if this is about the level of brightness you'd expect, or is this more consistent with the "old screens" or a counterfeit one? The grids seem slightly sloppy to me--you can't see in the photo, but one line on the right gets a little thinner and you see the fresnel lines, and I can see the top and bottom diameter portions of the split prism (ie, I see two circular lines very close to each other).

I've attached photos to show the difference. I only have an iphone so I can't really control the exposure, but I think the Acute Matte D screen (grid) is a little more exposed than the Maxwel, yet it still looks dimmer to me. It's not night and day or anything, but it still bugs me, and if anyone has any input I'd greatly appreciate it.

Yes, the camera is on my kitchen floor, looking at the dishwasher and kitchen table. It's the brightest room in the house and it's dark outside...

Certainly it's easier to focus and still plenty bright--I'm just a little anxious about a spending so much on the new Acute Matte screen and it being dimmer than my Maxwell. Thanks!

I posted in another thread that after tons of focus error, I had both bodies serviced. That laid the errors to rest, but one body had the pre 'D' acute matte & even it worked fine - but not as bright. I've seen the 'D' version, but not used it for shooting. The tech that serviced the bodies told me I'd get about 2 stops more brightness w/ the Maxwell. 'Probably not quite that much over the early acute matte, but definitely that much over the pre AM screen. 'Don't know if Sirius has experience w/ AM, Beattie, Maxwell, but I'd want to hear from him if I were you. I can't afford another Maxwell, but if I were to pony up the funds, another Maxwell would be my choice.

I have only had two screens, both Accumat one with the two focusing collars and one with the focusing grids but with vertical and horizontal lines. I use the later since I do not need the focusing grids with the PME.

Hard to say from the pics, as the one on the right seems to have a little focus error or camera (phone) shake. Things are sort of blurry on that pic, especially the tiles. The image on the left is much brighter. If I had a choice, I would use the left one, even w/o the split prism.

FWIW, I think Momus is on to something. One thing I noticed before the Maxwell screen arrived was that the plain matte screen was pretty easy to focus. The 'snap' when focus came in produced as good a result as all the aids. I found focusing slow at first - slower w/ the focusing aids 'cause I was trying to get it so perfect. The matte screen was there or not - no fussing, tilt/twist to get the split clear.

It is not a 1-1 comparison but I had an Acute Matte D for my 501CM and a Maxwell hi-lux whatever for my RB67. The Maxwell was a bit darker but that was purely down to the RB lens being f/3.5 instead of f/2.8. If I stopped down the Hassy to f/3.5 it look about the same. Focus snap seemed a bit better with it but again not a 1:1 comparison.

One thing, Bill Maxwell makes various screens, for starters he can either recoat an existing screen or make a brand new one from whatever it is he is using. I got a brand new one which is apparently brighter than anything he can do recoating/processing existing screens. There is also an additional process he does I think which may or may not improve brightness. I got a plain matte hi-lux made from new.

In any case, if you don't like the Acute Matte D I'm sure you can sell it on ebay and get most, if not all, your money back! When my Hassy died I sold the screen alone for £200.

I have used the Acute-matte (plain, grid w split), Acute-Matte D (plain), Britescreen (split+micro), Beattie (plain), Bos (plain), and all the earlier Hasselblad screens. Eventually I'll get to try a Maxwell.

The D and non-D Acute-Mattes are the same brightness, the D has been modified to make fine focusing a little more precise for slower lenses, I find the difference is pretty subtle, and probably not worth the $ difference.

The Britesceen is the same brightness as the Acute-Mattes, except the grain is a bit courser, but the fresnel is finer and less visible. It is currently my main screen.

The Beattie was brighter, but it was much harder to determine when the image was in focus. Keep in mind there were many variations of this screen optimized for specific lenses, and as they are not so marked, my experience with this one may not have been optimal. But I did try a few others, and I found them all the same.

The Bos was great in bright light, but as it was fairly dim, it was not easy to use in poor light. It is a grainless wax layer sandwiched in glass screen, but was not properly adjusted for correct focus plain on my V bodies (it was probably meant for a 500C) and needed shimming for work properly.

The old Hasselblad screens were dimmer (~2 stops), but in bright light, were easy to focus. I used the old microprism one for years, as it was acceptable in dimmer light.



There is a limit to how bright you can make a screen and have it show enough contrast to focus. As you let more light through, or redirect the light towards the eye with the fresnel or prismatic textures, you get less in-and-out of focus contrast. That is the reason why most modern screens are all about the same brightness, there is a balance where you've brightened the image but still can focus. It is the reason the Beattie is brighter but harder to focus. Autofocus cameras can allow a brighter screen because they compensate with an autofocus module to confirm focus. The Fresnel and prismatic textures are also optimized for focal length and f-stop, if you take a consumer AF SLR, and stick a large aperture lens on it, its very difficult to manual focus precisely, as those screens are optimized for slower zooms, and brightness at the cost of manual focus.

My advise is not to worry too much about the absolute brightness, but look at 1) is it bright enough. and 2) can you focus accurately in all conditions? Sometimes the brightest screen is not the best one. If you always use a focus aid, then you can trade off a brighter matte area for less focus contrast.

Ignoring the brightness question, if both are as easy to focus for you, I would select the one on the right because the lines allow you to line up horizontals and verticals.

They are both easy to focus with--though the split prism makes focusing easier. It's been a long time since I had a split prism (my 35mm days prior to 2003), so it's a little annoying at the moment to have that large circle in the middle--I didn't anticipate that. I'll try it out for a while and see how it works. I imagine outdoors both should be plenty bright.

I have had many a picture slightly ruined by verticals/horizontals being off (I prefer to print full frame, though I make occasional exceptions), so I also thought the grid would help, which is why I went for the split prism + grid.

Itsdoable - thx for weighing in. I learned some & appreciate your sharing that much experience w/ the various screens. I would never have guessed a screen could be too bright.