The fuji needs to be torn down and inspected. Perhaps it has been tampered or has separation. Everyone should test their equipmnet. I did similar tests between two Horseman lenses. The one with separation was indeed inferior upon side-by-side testing. http://www.largeformatphotography.in...lens-separatio
You can find any focus shift (or just plain operator error in focus) by looking at other areas of the film. The scene set-up is at a slight angle to the film plane so somewhere across the film you will find the precise plane of focus for each lens. It may not be in the same place on each piece of film.
If there is no sharp focus anywhere on the Fuji test film then there may be a lens problem.
Ok. Here's a new capture of the Fuji at F22 & 1/4'. It's the best I could do with the lighting. Also, below are new snips of the original Rodenstock images without the clipping function on. I'm only posting the images that were in my intended plane of focus this time...
Fuji Retest, Rodenstock Orig - Archway
Fuji Retest, Rodenstock Orig - Upper Right Brick Work
The 2nd Fuji exposure is under completely different conditions and has higher contrast due to the lighting, so no longer a valid comparison. It does show that there was clearly something wrong with the original Fuji exposure though. Probably just out of focus. At this point, I'm going to consider this one closed and move to re-testing these two lenses under better conditions at a higher shutter speed. I didn't intend to turn this into a science project, but then that's kind of what these end up being I guess. So, take the results for what they are. Thanks to everyone who responded. I found the various responses to be very informative.
Note: Deleted posts above due to issues with image uploads.
Check the film holder that you used on the first Fujinon shot. It could be shot/bent/worn/stuffed/loaded incorrectly.....
Lachlan.
You miss 100% of the shots you never take. -- Wayne Gretzky
Absolutely. With 4x5, I've settled on all Toyo holders. They're consistently closer to the ANSI "T" depth than Lisco/Fidelity holders, which can vary wildly, some of those being far outside the specified +/- 0.007" tolerance. Toyos are usually within +/- 0.002" and, fortunately, I bought mine before Toyo moved production off shore, then started delivering reeking holders.Originally Posted by Lachlan 717
For 5x7, I individually depth checked lots of holders and selected those that were close to the 0.228" "T" specification. When it comes to 8x10, although Toyo was very precise, the holders are much heavier than Lisco/Fidelity. Thus, I went to Calumet back in 1998 and depth checked piles of holders on the shelf, then bought a dozen that were very close to the 0.260" "T" specification.
Note that the smaller the film and shorter the lens focal length, the more critical emulsion position is. The OP's first Fujinon result could easily have been caused by bad film positioning.
To do anything resembling a true optical bench test you'd need a vacuum filmholder verified flat (measured with appropriate precision tools), equal measurement
of the film plane on the camera itself, verification of both standards for perfect parallel and flatness, the lensboard checked too, a precise target properly aligned.
Also note what Sal just said. This is how it has to be done.
For this test, I'd simply use the same holder (same side, of course). Have a changing tent next to the camera for a quick change to maintain light as best as possible.
One variable removed.
Lachlan.
You miss 100% of the shots you never take. -- Wayne Gretzky
One question for the OP:
How did you differentiate which sheet was from which lens? Given the Fujinon came out okay in the second "test", perhaps the Rodenstock is stuffed and you mixed up the negs?
Lachlan.
You miss 100% of the shots you never take. -- Wayne Gretzky
Well, one variable that might result in different results for the two lenses removed, but still a potential problem. That could cause both lenses to look like dogs.
Better to first depth check the holders and either use two sides with "T" very close to 0.197" or, if you can only find one like that, then do the 'change film between lens trials' routine.
No mix up with the lenses.
In the initial test, I noted the the lens used in the each of the exposure files in the ExpoDev software on my iphone. Each film holder's labeled side and it's # was noted there as well. Each label was removed from the film holder and attached to the developing drum as it was loaded. As each sheet of film came out of the drums it was marked accordingly.
In the future though, I will check the depth on the film holder and include the lens id in the image itself.
Appreciate all great details provided here.
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