Profiles for Mamiya 645AF lenses? Home made solution?

[marktomaras]

Hello All,

I just bought a pair of older Mamiya 645 AF lenses to use with my Phase One DF+ & IQ160. My real budget went towards the back and a technical camera and lenses, but since I bought the DF+ and modern Schneider 80mm lens, I thought it might be nice to take advantage of the low cost 645AF lenses for a couple of useful focal lengths.

I chose the 210mm ULD f/4 & 55mm f2.8

I received the 55mm today in the mail, and though my expectations are low, I was a bit underwhelmed. Truth be told, it has good performance in the center, and at f/8, the performance carries outward a little bit as well. I think for environmental portraits at f/5.6 & f/8, I should be in good shape until budget allows for a more modern lens.

The 210mm comes in tomorrow's mail, and my expectations are quite a bit higher for that lens.

So, in post, I see that there are not any profiles in Capture One or Lightroom for these older lenses. Today, I experimented with LCC shots at each aperture with the 55mm lens and created LCC adjustment files in C1. It worked well for the vignetting, but does not correct for distortion or CA.

Has anyone found any profiles for these older lenses? Or perhaps created their own with the simple manual controls? If someone told me that they found that the 55mm 645AF lens requires a distortion adjustment of X and a vignetting adjustment of Y, that could be a great help. Or perhaps share some of the methodology of determining how to create a relatively effective profile using the manual controls on C1 or LR. Is LCC a good way to begin? I would love to have (or create) a formula/profile for the 55mm that corrects for some of the lens's shortcomings. Ditto for the 210mm ULD, though I expect it will need less correction than the 55mm.

Thanks!
Mark

 

[gebseng]

Hi,

I have the same two lenses with the DF+ and a Credo 40 back. I found two solutions:

- manually choose the "Mamiya Sekor LS 55mm / f2.8" profile built into Capture One. AFAK, this lens has the same optical design as yours.

- or use the Tom Niemann's great PTLens software: http://www.epaperpress.com/ptlens/index.html .
If your lens/sensor combination is not included yet, you can send him a calibration target, and he will update his database with the distortion data for your lens/sensor.

best,

geb

 

[marktomaras]

Thanks Geb, I had not heard of PTLens, I will be sure to check it out. Of course a RAW solution is the most desirable, but if it does not exist, we have to accept the next best thing.

Are you using any RAW lens correction, manual or otherwise, with your shots from the 210mm ULD lens?

 

[Paul2660]

The LCC in C1 will only correct color cast and light fall off. It's not going to help on CA, or distortion.

I never found too much distortion with the 55 F2.8, but it does have a bit of light fall off wide open.

PTlens as already mentioned will help in post, or the newer tools in Adobe CC, which can help with distortion. This would be a manual fix each time in Adobe as I don't think you can save the settings.

For CA, C1 will always allow a manual correction, with the check box, there are two, one for CA, the other for de-fringing. This requires you to make the check boxes each time, but you can always adjust one image, then copy the settings to the rest, which is how I do it when I use manual adjustments.

Paul