PDA

View Full Version : Grandagon N 75mm/6.8 and fall-off



JaZ99
29-Nov-2015, 02:32
Hello,
after 2 years of shooting with my Graflex, I still consider myself as a newbie.
Currently I own 3 lenses: Fujinon 105/5.6, Caltar II-N 150/5.6 and Fujinon 240/9.
Now, I'm considering a new lens: Grandagon N 75/6.8 (Caltar II-N 75/6.8 a.k.a. Sinaron-W 75/6.8) to add to the mix.
I've been searching the internet for days looking for opinions, but I couldn't find any image examples of fall-off without center filter.

I shoot chromes mostly and I hate to crop too much.

Does anybody has any image showing how severe is (or isn't) the fall-off? I appreciate any help and opinions.

JaZ

biedron
29-Nov-2015, 07:46
Here are a couple of shots on Velvia 50 with a Grandagon Sironar N 75mm (f4.5 version) without a center filter. The Horseshoe Bend one has very minimal cropping (basically to eliminate the film rebate); the Ruin one has minimal cropping at the bottom, and a little more at the top.

Hope this helps.

Bob

142775 142776

Bob Salomon
29-Nov-2015, 08:12
Here are a couple of shots on Velvia 50 with a Grandagon Sironar N 75mm (f4.5 version) without a center filter. The Horseshoe Bend one has very minimal cropping (basically to eliminate the film rebate); the Ruin one has minimal cropping at the bottom, and a little more at the top.

Hope this helps.

Bob

142775 142776

But bear in mind, the 4.5 has a larger circle of illumination then the 6.8, so these really don't show what the fall off with the 6.8 would be.

DG 3313
29-Nov-2015, 09:06
I picked up a Grandagom 75mm 6.8 (pre-N) from a forum member and it covers 4x5 without a lot of camera movements. With a lens this wide.....I dont even use camera movements....I just stop it down. I havent seen fall off that bothers me with my old lens.

JaZ99
29-Nov-2015, 11:21
Thank you, appreciated! I love the ruin shot.


But bear in mind, the 4.5 has a larger circle of illumination then the 6.8, so these really don't show what the fall off with the 6.8 would be.

I've looked it up: it is 187mm vs 195mm. Do you think it does matter?

Bob Salomon
29-Nov-2015, 12:33
Thank you, appreciated! I love the ruin shot.



I've looked it up: it is 187mm vs 195mm. Do you think it does matter?
Of course it matters. Fall off begins about 30% out from the center. The 6.8 will have more in the corners then the 4.5.

JaZ99
29-Nov-2015, 13:11
Of course it matters. Fall off begins about 30% out from the center. The 6.8 will have more in the corners then the 4.5.

Oddly enough, I couldn't find MTF charts for 75mm on Rodenstock web site (http://www.rodenstock-photo.com/Archiv/e_Rodenstock_Analog_Lenses_27-42__8226.pdf). But there are ones for 90mm and it seems 6.8 is even slightly better than 4.5 @f22. But I don't have much experience in reading MTF charts.

Bob Salomon
29-Nov-2015, 13:51
Oddly enough, I couldn't find MTF charts for 75mm on Rodenstock web site (http://www.rodenstock-photo.com/Archiv/e_Rodenstock_Analog_Lenses_27-42__8226.pdf). But there are ones for 90mm and it seems 6.8 is even slightly better than 4.5 @f22. But I don't have much experience in reading MTF charts.

The 75mm 6.8 has been out of production for several years so they no longer have that brochure. Actually all of the Grandagon-N and Apo Grandagon lenses are now out of production but the brochure that you looked at is the last of the analog brochures so some of the later discontinued lenses are still there.

Emmanuel BIGLER
30-Nov-2015, 01:50
Oddly enough, I couldn't find MTF charts for 75mm on Rodenstock .

I have a copy of those charts for the Grandagon-N 75 mm f/6.8
Look here :
https://www.flickr.com/photos/43175600@N00/456327448/

I have this lens and I like it very much, but I use it mostly for 6x9 and 6x12 on 120 rollfilm, not for 4x5".
I have used the center filter occasionnally, but you can start without it and see if the images are OK for you or not.

JaZ99
30-Nov-2015, 02:56
I have a copy of those charts for the Grandagon-N 75 mm f/6.8
Look here :
https://www.flickr.com/photos/43175600@N00/456327448/


Thank you, that was very helpful.