joe_accuardi Posted July 15, 2001 Share Posted July 15, 2001 Hello,I am writing because I have been pondering this question. Why is it that when I look under my enlarger with my grain focuser the image is not as sharp as the same image taken with my Hasselblad... Technically, I believe that the 4x5 image should be sharper due to less enlargement. I am using T-Max 100, developed in HC-110, but I have now purchased some TMAX RS developer. I have also noticed this on some chromes that I have taken. One theory, is that my ground glass, is cheap; purchased at a glass shop for $1, versus $50 for a Linhof brand. Could this throw off my focusing? I am stopping the lens down pretty far when i shoot (f/22 or so) so I wouldn't think that there would be too much difference if it was focusing on the front of the glass versus the back, but maybe??? I am using a loupe when I focus, so it is not my eyes... Please let me know of any insight that you may have... Thanks!!! Joe Accuardi Portland, OR Link to comment Share on other sites More sharing options...
cesar_barreto Posted July 15, 2001 Share Posted July 15, 2001 Joe, <p> Unhappily, even new cameras can show some difference on focusing and film planes. It must be checked and somewhere back in this forum you may find some suggestions on how to do it. Maybe your camera was set for a fresnel lens and it's absence can really make a mess on focusing. But, anyway, don't despair. It's easy to find and fix those small bugs. Good luck. <p> Cesar B. Link to comment Share on other sites More sharing options...
bob_salomon3 Posted July 16, 2001 Share Posted July 16, 2001 1: Have you installed the ground glass properly? 2: Is some of the image sharper in front or behind what you focused on? 3: Is the lens propely installed and are you shooting within the optimal range of the lens or are you using too large or small an aperture to get best results? 4: There are no ground glasses from linhhof for a III. 5: Your camera series has been discontinued since 1956. Has it been checked to see if it is within factory tolerances after almost half a century? Link to comment Share on other sites More sharing options...
martin_jangowski Posted July 16, 2001 Share Posted July 16, 2001 Joe, <p> there is a well known method to check the planes of ground glass and film: use a richly structured object (a page of a newspaper or a ruler) going from the front into the background and make a image with the stop wide open. You should put something on the rules/paper to mark the line of best focus. Since you use the lens wide open, you should have a small sharp zone in the middle and unsharp zones in front and behind your marker. If the zone of sharpness isn't on the marker, you have a problem with the ground glass. Don't use movements with this test! Link to comment Share on other sites More sharing options...
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