Wondering if anyone else is using the Cambo Actus Mini out here?
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I'm trying to see if anyone has used the a Copal 1 lens with a large flange on the Actus Mini. The Rody 180 I mention in another thread has a large flange, seemingly larger than is meant for the Actus Mini. I don't know enough about lens design to understand how that would make an impact?I don't know if Rich hangs out here, but he uses one of these with Sony A7... cameras. He posts over at DPReview and FredMiranda. Just today we were exchanging some thoughts about his new Laowa 20mm that he's using on his Cambo Actus setup. https://www.fredmiranda.com/forum/topic/1774231/2#16074627
I did some more research. I confused flange with image circle. Actus mini recommends a flange no bigger that 70mm. Found a note on B&H that's is only 60mm for the 180mm. So now I just need to put an offer on the 180 and get a Cambo Actus mount for Copal 1.Cambo sells the ACB-1 Lensplate for Copal 1. Presumably that means you can put a Copal 1 shutter on the board, and therefore on the Actus. The rear cell of the HR Digaron-S 180/5.6 seems large, but not enormously large.
I get the sense I'm missing something here Jeff. What do you mean by it has a "large flange, seemingly larger than is meant for the Actus Mini"? Are you talking about the flange focus distance of the lens, or the actual diameter of the lens flange, which mates to the ACB-1?
Ah, that makes sense.I did some more research. I confused flange with image circle. Actus mini recommends a flange no bigger that 70mm. Found a note on B&H that's is only 60mm for the 180mm. So now I just need to put an offer on the 180 and get a Cambo Actus mount for Copal 1.
I don't understand this. Maybe you should download Lenses for digital photography pdf from https://www.rodenstock-photo.com/service#download_center . Look drawing at page 5. Lenses flange focal distance ( d ) is measured from the lens plate to the sensor.I did some more research. I confused flange with image circle. Actus mini recommends a flange no bigger that 70mm. Found a note on B&H that's is only 60mm for the 180mm. So now I just need to put an offer on the 180 and get a Cambo Actus mount for Copal 1.
The 180 degrees swing would add the needed distance to reach FFD and it really does! I know. According to the manual of Actus it adds 45 mm. And so did I also measure.The current production Rody 180mm lens cannot be used with the short rail as posted above - at least with a GFX or Sony 7RM4. I have never adjusted the front swing 180 degrees but that would add the needed distance to reach FFD.
I enthusiastically echo Victor's point. In fact, I would say that you can't rely on the labelled indicators, and you might not be able to rely on the detent if one exists. Sometimes the detent is not accurately located, and sometimes it's worn from use so there's a bit of play. This makes it very important to check for parallelism. These kinds of cameras should all be user adjustable, but not all are.Anyone considering the Actus (or any bellows system) should be aware that the front and rear standards must be parallel to each other IF the intended goal is focus accuracy across the frame. Engraved numbers should not be relied upon unless proven to be reliable. The accuracy needed is in the 1000th of a degree range and a cavalier approach will result in inferior images. Live view at 100% pixels is an invaluable aid in the field for checking parallelism. I have developed a quick in the field check for parallelism that has proven to be repeatably accurate.
The benefit of the Cambo Actus series is that it is truly portable and easily transported.
Thanks for the extra info Victor, and I hope I didn't come across as being overly picky here. I was worried someone interested in using the tools would run away at the thought of needing such tight tolerances!Rob..... thank you for pointing out that my reference to 1/1000 of a degree may be a tad too small but probably only by one zero. I had re-read Togers excellent review of the Linhof Techno (a camera I would not own for various reasons) where he set up an example of swing parallelism accuracy to be acceptable if 0.1 degree tolerance L/R could be achieved. He was, at the time, dealing with 6um pixel pitch which now is significantly smaller (3.76) so more than likely to achieve the same accuracy L/R a tolerance of 1/100 degree should be the goal and more than likely if off by that amount can be seen at 100% pixels. I also don't have any type of equipment to come close to that type of measuring capabilities but I'm sure they exist. Regardless - parallelism is critical but adjustable. More importantly is that once set is only good for that lens at that time. Each lens can have a slight tolerance difference that requires a little tweaking of the front standard - but the Cambo is capable of achieving that accuracy.
The 180 does indeed work with rotating the front standard!I have an Actus Mini, which I use with a Sony A7rIII & a variety of lenses, Digitars, Canon T/S & Pentax 645 & 67. The longest digitar I have is a 120 but its in a Copal 0. I swing the front standard 180deg when using this lens, so that the focus scale is set to infinity. I see no reason why a 180 Rody wouldn't focus at infinity if you swung the front standard, though I believe you can get a longer rail & you may also need the long bellows. If you want to be 100% sure you could always email Cambo