Petzval without flint

[vitality]

Well, basically idea is to use petzval with only one glass element from rear group. Take out flint and leave front doublet and crown at the back. Did somebody try to experiment with this kind of setup?
I was searching info in internet and on this forum, but didn't get any results (most likely "my bad"). So, decided to give a try.
E. Suter Basel petzval 14" F4.3, with only crown at the back makes around 10" lens and approx F3 for exposure metering.
And result (open wide, 4x5 negative):

I f**d up a little bit during taking picture, so needed to use PS, as a result - not so good example for test shot. But if some of you was trying to do the same, or there is more info on such "setup", please let me know.

Thank you and I hope it will be interesting to someone.

[chassis]

Looks nice. Might be interesting to see an image of a higher key subject.

[c.d.ewen]

Well, basically idea is to use petzval with only one glass element from rear group. Take out flint and leave front doublet and crown at the back. Did somebody try to experiment with this kind of setup?

Vitality:

Take a look here.

Charley

[vitality]

Vitality:

Take a look here.

Charley

Thank you very much. I've been reading your test before I decided to try. It's very interesting how you can play around with petzval design.
But if I understand, you didn't try to use doublet + crown setup in your test?

Today checked with another 2 petzvals (12" & 16"), both show ~1.5x decrease of FL when flint removed (eg. 400mm becomes ~265mm). Picture shows some "softness".

If you turn around lens (crown at the front, doublet at the back) - FL of this setup is even more shorter. Picture becomes very soft (tested on white board, so not so much to tell about image quality, just appears very soft).

[vitality]

Just small remark:
Many people may ask: why to bother and play around with perfect lens like petzval, just shoot with it and enjoy?

Point of the test was to find a cheap soft focus lens (yeah yeah, keep dreaming ). You have your perfect petzval, you shoot with it, but when you want to go "soft", you simply remove flint and here you go - shoot "soft" ("more soft", than just changing space between rear elements).

I would appreciate (and I think not only me), if somebody from SF lens users, could give a quick try for such setup and give some review. How does it look, how does it compare to expensive SF lenses, does it give better result, than just using doublet on it own (or not to bother and when you want SF lens from your petzval, just use only front achromat)? Or may be this kind of setup doesn't give anything close to soft focus lens, and it is just low quality image and nothing to do with SF?

And I understand, that to someone, it might appear stupid or useless kind of experiment.

[eddie]

Or may be this kind of setup doesn't give anything close to soft focus lens, and it is just low quality image and nothing to do with SF?

exactly!

[Paul Fitzgerald]

"Point of the test was to find a cheap soft focus lens (yeah yeah, keep dreaming ). You have your perfect petzval, you shoot with it, but when you want to go "soft", you simply remove flint and here you go - shoot "soft" ("more soft", than just changing space between rear elements).

I would appreciate (and I think not only me), if somebody from SF lens users, could give a quick try for such setup and give some review. How does it look, how does it compare to expensive SF lenses, does it give better result, than just using doublet on it own (or not to bother and when you want SF lens from your petzval, just use only front achromat)? Or may be this kind of setup doesn't give anything close to soft focus lens, and it is just low quality image and nothing to do with SF?"

Too bad you will never get a straight answer to this, too many people have way too much money involved for that to happen.

"Just small remark:
Many people may ask: why to bother and play around with perfect lens like petzval, just shoot with it and enjoy?
.....
And I understand, that to someone, it might appear stupid or useless kind of experiment."

It's not stupid or useless, it's a hobby, have fun with it. Most lenses are convertible and most become softer-focus by doing so. Play with them all to see what you like and what you don't. You will see the results on the GG instantly, some work, some don't. Color fringing usually makes them un-usable with color films. Focus shift is fun also, what you see is not always what you get on film.

Have fun with the hunt.

[vitality]

exactly!

Thank you! I had some doubts

It's not stupid or useless, it's a hobby, have fun with it. Most lenses are convertible and most become softer-focus by doing so. Play with them all to see what you like and what you don't. You will see the results on the GG instantly, some work, some don't. Color fringing usually makes them un-usable with color films. Focus shift is fun also, what you see is not always what you get on film.

Have fun with the hunt.

Thank you. I think, that photography was always going together with question "what if..." (experimenting).
About soft focus effect, for me it's just hard to say does it look like SF, or it's just loss of quality. To me (so far) it looks the same. Must be because I didn't use yet a proper SF lens, and as soon as I try one, I'll be able to see difference between good SF and bad ones

[eddie]

[QUOTE=vitality;806454
About soft focus effect, for me it's just hard to say does it look like SF, or it's just loss of quality. To me (so far) it looks the same. Must be because I didn't use yet a proper SF lens, and as soon as I try one, I'll be able to see difference between good SF and bad ones [/QUOTE]

bottom line is if you are enjoying what you have and the images you make then do not bother with other options. ....trust me it will save you thousands of dollars! and easily 10s of thousands!

my suggestion for you is to attend a work shop like Jim Galli had at his place back in May. it was awesome. he/we talked about SF lenses. looked at prints from almost every SF lens made! did wet plate collodion and hung out and shot all around the desert. it was great. (e mail him and tell him you wanna do it again next year.....i will do the same. Jim, you listening? we wanna come back to Tonopah!) trying to understand the nuances of SF lenses is difficult to do with the written word and the scanned an posted images. it is FAR easier to talk with some one with actual prints in your hand. it is about shadow spilling onto highlights....and highlights spilling onto shadows.....and halo....and softness....and sharpness......and glow.....and bokeh....and .....and....oh well.....you get it.

besides the different lenses SF is very much affected by exposure, development, and printing times in a huge way....HUGE! i saw Bob Carnie print a neg using a darkroom techniques that would make you shoot with one sharp lens and play in the darkroom for the rest of the time....it was amazing. (thanks Bob).

in the end of the day you will have fun exploring the SF lens world. have fun and welcome to therapy.....OH! and if you wanna skip right to the end/best SF lens you will ever use....... and miss all the experimenting along the way i can sell you a super nice pinkham and smith lens. this way you will not waste any unnecessary money on your journey. you can just skip to the end.....like reading the last chapter of a book! ...and get the best available lens*.

cheers

eddie


*there is one better but you NEVER see it......and i already sold it.....

[Paul Fitzgerald]

"for me it's just hard to say does it look like SF, or it's just loss of quality."

vitality, the big dividing line between a proper SF lens and loss of quality is easy.

IF you can get the eye lashes sharp with all else soft it's a proper SF lens.
if you can NOT get the lashes sharp with all else soft, it's just loss of quality.

It will still come down to distance, focus, f/stop, lighting, film choice, development, printing, the planets aligning, ect.