LF Lenses - APO or Digital

[rga]

Hi All,

I will need to buy new LF (4x5) lenses. Mine are decades old and have coating issues and shutter issues (prontors!).

Though new digital lenses are being marketed strongly, I'm wondering what advantage they offer over APO lenses used in conjunction with LCC. Seems to me that any chromatic aberrations would be addressed very well by LCC to the point where, even on a large print, the difference between an LCC adjusted APO lens and a newer lens designed for digital would probably not be apparent.

So anyone with any experience using the two or any pointers as to where my thinking has gone astray?

Thanks for any light shed on this subject,
Bob

 

[gazwas]

The new Schneider and Rodenstock "digital" lenses don't cover 5x4 and many only just cover the MF 6x6cm film area.

OK if your shooting with a MF digi back on a 5X4 camera but not for film.

 

[rga]

That I did not know!
Thanks. Makes the decision easier. I like to move my back standard around with a MF back and then stitch.

 

[gazwas]

That I did not know!
Thanks. Makes the decision easier. I like to move my back standard around with a MF back and then stitch.

With something like a P45 a digital wide lenses will be ok (depending on model) between 10 and 15mm shift. Some not quite as extreme wide will go more but you have to deal with a lot of light fall off which if doing LCC corrections can degrade the IQ at the edges.

 

[routlaw]

Hi All,

Though new digital lenses are being marketed strongly, I'm wondering what advantage they offer over APO lenses used in conjunction with LCC. Seems to me that any chromatic aberrations would be addressed very well by LCC to the point where, even on a large print, the difference between an LCC adjusted APO lens and a newer lens designed for digital would probably not be apparent.

So anyone with any experience using the two or any pointers as to where my thinking has gone astray?

Bob

Bob

Some of the digital lenses will cover, barely and I do mean barely 4x5 leaving little to any room for movements. The longer focal lengths generally will also cover 72x96 for scan backs. Also understand there are different iterations of digital lenses, some designed only for MFD and thus really do have coverage only for those backs.


The short and sweet of it is simply to buy either Rodenstock APO or Schneider APO lenses of recent origin. And I will say this my Sironar S APO 135 mm will almost go toe to toe with the one apo digital lens I own, the 105. Other things to consider are how these lenses are optimized. Digital lenses depending on what generation are optimized for F8-F11 and degrade to less than regular film lenses by F16. Some of the newer digital lenses are optimized at F5.6 wide open to F8. Obviously these DOF apertures will not go very far using traditional film methods. By contrast most of the newer Sironar S APO designs are optimized for F11-F16 or F22 with longer focal lengths.

I hope this helps.

Rob

 

[rga]

Helps a lot Rob. Thank you!

My 4x5 kit came with lenses that are now failing me (they're quite old) and I need to buy a new set.

I've been told that stopping down beyond f8 with a MF back is not a good thing to do. Is that true? With LF film, it was all about stopping down and I'd prefer to keep it that way.

Also, is there a good place where I can order a lens mounted for my rig? It's a Linhof Technikarden S. I can't use my current lens boards as they have prontor shutters.

Finally, which is the best shutter type to get from an accuracy and longevity stand point?

Thanks for any guidance anyone can provide,
Bob

 

[routlaw]

I've been told that stopping down beyond f8 with a MF back is not a good thing to do. Is that true? With LF film, it was all about stopping down and I'd prefer to keep it that way.

Also, is there a good place where I can order a lens mounted for my rig? It's a Linhof Technikarden S. I can't use my current lens boards as they have prontor shutters.

Finally, which is the best shutter type to get from an accuracy and longevity stand point?

Thanks for any guidance anyone can provide,
Bob

Well that all depends upon the actual pixel size and understand this issue applies to DSLR's as well as MFD. The rule of thumb I have gone by is fairly simple (though I am sure there are more complex and scientific methods) for F stop for a given sensor. First and foremost know what the pixel size in microns. So lets say you have a sensor with a 9 micron size (ie Nikon D3, Leaf Aptus II-5 etc), so theoretically one could stop down to F13.5 (using a multiplier of 1.5 x pixel size) before diffraction loss kicked in thereby reducing contrast, IQ and detail. But for a sensor with say 6 microns such as the Nikon D3x you could only go to F9. And that really is about its limit, stopping down to F11 will reduce its detail and contrast. The quality of optics can stretch this from my experience a little but not by much.

As for shutters, just about all of them come with Copal 1, 0, or 3 these days and in fact I have yet to ever own a LF lens with anything other than Copal shutters and have yet to have an issue, ever. Knock on wood.

Jeff at Badger Graphic in WI has been good to deal with, Midwest Photo Exchange - Jim Andraki, and of course KEH is hard to beat as well. They usually have a large selection LF glass on hand.

I would also pay for a one year subscription to Lloyd Chambers website and reviews, it will be the best $35.00 you might ever spend IMHO. And while he does not deal with LF per se, he extensively, ruthlessly reviews all other digital gear from Nikon, Hassy, Leaf you name it. Some of his findings and results are not what you might expect.

Rob

 

[rga]

Thanks Rob for all of you input and suggestions. With a P45+ f10 would be about the limit per your calc. I will experiment.

And also thanks for the vendor leads and info about Lloyd Chambers. Much appreciated,
Bob

 

[routlaw]

Thanks Rob for all of you input and suggestions. With a P45+ f10 would be about the limit per your calc. I will experiment.

And also thanks for the vendor leads and info about Lloyd Chambers. Much appreciated,
Bob

I come up with just shy of F11 (F10.8 to be exact). But my guess is if you had top optics you could stretch this a bit to F16 if needed, probably somewhat scene dependent. If you don't have a lens chart one of the best homemade charts I have found is a good map with a currency note pasted onto it. I have a map of Olympic NP with a $5 bill taped to it. Its quite reveling when things head south due to lens issues, diffraction and what have you.

Good luck. Understand Lloyd is not a fan boy for any of these companies and post dozens of images for illustration to back up his findings. Another website you might investigate also is Joseph Holmes. A year or so ago he did some extensive research on optics, and digital imaging. The info was thick, heady and technical so be prepared.

Rob

 

[gazwas]

Thanks Rob for all of you input and suggestions. With a P45+ f10 would be about the limit per your calc. I will experiment.

NEVER go by calculations as they are very one dimensional and you should always test. For example, just because a digital lens may be it's sharpest at f5.6 or f8, these calculations often refer to the centre of the lens. F11 may not be as sharp in the centre but the edges might be much better. As your interests seem to be landscape f11 would yield a better overall result IMO.

 

[rga]

Love the lens chart suggestion!

 

[Anders_HK]

These can help;

http://www.rodenstock-photo.com/mediabase/original/e_Rodenstock_Digital_Lenses_3-26__8236.pdf

http://www.schneiderkreuznach.com/pdf/foto/digitare_e.pdf

In above note also Rodenstock's description of their different series for digital.

Regards
Anders